- Some cleanup of the main index page for easier navigation
- Rework some of the other top-level pages for better readability and, with
luck, fewer merge conflicts in the future.
- Submit-checklist improvements, hopefully the first of many.
- New Italian translations
- A fair number of kernel-doc fixes and improvements. We have also dropped
the recommendation to use an old version of Sphinx.
- A new document from Thorsten on bisection
...and lots of fixes and updates.
-----BEGIN PGP SIGNATURE-----
iQEzBAABCAAdFiEEIw+MvkEiF49krdp9F0NaE2wMflgFAmXvKVIACgkQF0NaE2wM
flik1gf/ZFS1mHwDdmHA/vpx8UxdUlFEo0Pms8V24iPSW5aEIqkZ406c9DSyMTtp
CXTzW+RSCfB1Q3ciYtakHBgv0RzZ5+RyaEZ1l7zVmMyw4nYvK6giYKmg8Y0EVPKI
fAVuPWo5iE7io0sNVbKBKJJkj9Z8QEScM48hv/CV1FblMvHYn0lie6muJrF9G6Ez
HND+hlYZtWkbRd5M86CDBiFeGMLVPx17T+psQyQIcbUYm9b+RUqZRHIVRLYbad7r
18r9+83DsOhXTVJCBBSfCSZwzF8yAm+eD1w47sxnSItF8OiIjqCzQgXs3BZe9TXH
h2YyeWbMN3xByA4mEgpmOPP44RW7Pg==
=SC60
-----END PGP SIGNATURE-----
Merge tag 'docs-6.9' of git://git.lwn.net/linux
Pull documentation updates from Jonathan Corbet:
"A moderatly busy cycle for development this time around.
- Some cleanup of the main index page for easier navigation
- Rework some of the other top-level pages for better readability
and, with luck, fewer merge conflicts in the future.
- Submit-checklist improvements, hopefully the first of many.
- New Italian translations
- A fair number of kernel-doc fixes and improvements. We have also
dropped the recommendation to use an old version of Sphinx.
- A new document from Thorsten on bisection
... and lots of fixes and updates"
* tag 'docs-6.9' of git://git.lwn.net/linux: (54 commits)
docs: verify/bisect: fixes, finetuning, and support for Arch
docs: Makefile: Add dependency to $(YNL_INDEX) for targets other than htmldocs
docs: Move ja_JP/howto.rst to ja_JP/process/howto.rst
docs: submit-checklist: use subheadings
docs: submit-checklist: structure by category
docs: new text on bisecting which also covers bug validation
docs: drop the version constraints for sphinx and dependencies
docs: kerneldoc-preamble.sty: Remove code for Sphinx <2.4
docs: Restore "smart quotes" for quotes
docs/zh_CN: accurate translation of "function"
docs: Include simplified link titles in main index
docs: Correct formatting of title in admin-guide/index.rst
docs: kernel_feat.py: fix build error for missing files
MAINTAINERS: Set the field name for subsystem profile section
kasan: Add documentation for CONFIG_KASAN_EXTRA_INFO
Fixed case issue with 'fault-injection' in documentation
kernel-doc: handle #if in enums as well
Documentation: update mailing list addresses
doc: kerneldoc.py: fix indentation
scripts/kernel-doc: simplify signature printing
...
-----BEGIN PGP SIGNATURE-----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=5V9t
-----END PGP SIGNATURE-----
Merge tag 'rfds-for-linus-2024-03-11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 RFDS mitigation from Dave Hansen:
"RFDS is a CPU vulnerability that may allow a malicious userspace to
infer stale register values from kernel space. Kernel registers can
have all kinds of secrets in them so the mitigation is basically to
wait until the kernel is about to return to userspace and has user
values in the registers. At that point there is little chance of
kernel secrets ending up in the registers and the microarchitectural
state can be cleared.
This leverages some recent robustness fixes for the existing MDS
vulnerability. Both MDS and RFDS use the VERW instruction for
mitigation"
* tag 'rfds-for-linus-2024-03-11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
KVM/x86: Export RFDS_NO and RFDS_CLEAR to guests
x86/rfds: Mitigate Register File Data Sampling (RFDS)
Documentation/hw-vuln: Add documentation for RFDS
x86/mmio: Disable KVM mitigation when X86_FEATURE_CLEAR_CPU_BUF is set
- The biggest change is the rework of the percpu code,
to support the 'Named Address Spaces' GCC feature,
by Uros Bizjak:
- This allows C code to access GS and FS segment relative
memory via variables declared with such attributes,
which allows the compiler to better optimize those accesses
than the previous inline assembly code.
- The series also includes a number of micro-optimizations
for various percpu access methods, plus a number of
cleanups of %gs accesses in assembly code.
- These changes have been exposed to linux-next testing for
the last ~5 months, with no known regressions in this area.
- Fix/clean up __switch_to()'s broken but accidentally
working handling of FPU switching - which also generates
better code.
- Propagate more RIP-relative addressing in assembly code,
to generate slightly better code.
- Rework the CPU mitigations Kconfig space to be less idiosyncratic,
to make it easier for distros to follow & maintain these options.
- Rework the x86 idle code to cure RCU violations and
to clean up the logic.
- Clean up the vDSO Makefile logic.
- Misc cleanups and fixes.
[ Please note that there's a higher number of merge commits in
this branch (three) than is usual in x86 topic trees. This happened
due to the long testing lifecycle of the percpu changes that
involved 3 merge windows, which generated a longer history
and various interactions with other core x86 changes that we
felt better about to carry in a single branch. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
-----BEGIN PGP SIGNATURE-----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=3v4F
-----END PGP SIGNATURE-----
Merge tag 'x86-core-2024-03-11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull core x86 updates from Ingo Molnar:
- The biggest change is the rework of the percpu code, to support the
'Named Address Spaces' GCC feature, by Uros Bizjak:
- This allows C code to access GS and FS segment relative memory
via variables declared with such attributes, which allows the
compiler to better optimize those accesses than the previous
inline assembly code.
- The series also includes a number of micro-optimizations for
various percpu access methods, plus a number of cleanups of %gs
accesses in assembly code.
- These changes have been exposed to linux-next testing for the
last ~5 months, with no known regressions in this area.
- Fix/clean up __switch_to()'s broken but accidentally working handling
of FPU switching - which also generates better code
- Propagate more RIP-relative addressing in assembly code, to generate
slightly better code
- Rework the CPU mitigations Kconfig space to be less idiosyncratic, to
make it easier for distros to follow & maintain these options
- Rework the x86 idle code to cure RCU violations and to clean up the
logic
- Clean up the vDSO Makefile logic
- Misc cleanups and fixes
* tag 'x86-core-2024-03-11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (52 commits)
x86/idle: Select idle routine only once
x86/idle: Let prefer_mwait_c1_over_halt() return bool
x86/idle: Cleanup idle_setup()
x86/idle: Clean up idle selection
x86/idle: Sanitize X86_BUG_AMD_E400 handling
sched/idle: Conditionally handle tick broadcast in default_idle_call()
x86: Increase brk randomness entropy for 64-bit systems
x86/vdso: Move vDSO to mmap region
x86/vdso/kbuild: Group non-standard build attributes and primary object file rules together
x86/vdso: Fix rethunk patching for vdso-image-{32,64}.o
x86/retpoline: Ensure default return thunk isn't used at runtime
x86/vdso: Use CONFIG_COMPAT_32 to specify vdso32
x86/vdso: Use $(addprefix ) instead of $(foreach )
x86/vdso: Simplify obj-y addition
x86/vdso: Consolidate targets and clean-files
x86/bugs: Rename CONFIG_RETHUNK => CONFIG_MITIGATION_RETHUNK
x86/bugs: Rename CONFIG_CPU_SRSO => CONFIG_MITIGATION_SRSO
x86/bugs: Rename CONFIG_CPU_IBRS_ENTRY => CONFIG_MITIGATION_IBRS_ENTRY
x86/bugs: Rename CONFIG_CPU_UNRET_ENTRY => CONFIG_MITIGATION_UNRET_ENTRY
x86/bugs: Rename CONFIG_SLS => CONFIG_MITIGATION_SLS
...
not) a NMI handler
- Ratelimit unknown NMIs messages in order to not potentially slow down
the machine
- Other fixlets
-----BEGIN PGP SIGNATURE-----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=Jt9B
-----END PGP SIGNATURE-----
Merge tag 'x86_misc_for_v6.9_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull misc x86 fixes from Borislav Petkov:
- Fix a wrong check in the function reporting whether a CPU executes
(or not) a NMI handler
- Ratelimit unknown NMIs messages in order to not potentially slow down
the machine
- Other fixlets
* tag 'x86_misc_for_v6.9_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/nmi: Fix the inverse "in NMI handler" check
Documentation/maintainer-tip: Add C++ tail comments exception
Documentation/maintainer-tip: Add Closes tag
x86/nmi: Rate limit unknown NMI messages
Documentation/kernel-parameters: Add spec_rstack_overflow to mitigations=off
kernel to be used as a KVM hypervisor capable of running SNP (Secure
Nested Paging) guests. Roughly speaking, SEV-SNP is the ultimate goal
of the AMD confidential computing side, providing the most
comprehensive confidential computing environment up to date.
This is the x86 part and there is a KVM part which did not get ready
in time for the merge window so latter will be forthcoming in the next
cycle.
- Rework the early code's position-dependent SEV variable references in
order to allow building the kernel with clang and -fPIE/-fPIC and
-mcmodel=kernel
- The usual set of fixes, cleanups and improvements all over the place
-----BEGIN PGP SIGNATURE-----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=c1ps
-----END PGP SIGNATURE-----
Merge tag 'x86_sev_for_v6.9_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 SEV updates from Borislav Petkov:
- Add the x86 part of the SEV-SNP host support.
This will allow the kernel to be used as a KVM hypervisor capable of
running SNP (Secure Nested Paging) guests. Roughly speaking, SEV-SNP
is the ultimate goal of the AMD confidential computing side,
providing the most comprehensive confidential computing environment
up to date.
This is the x86 part and there is a KVM part which did not get ready
in time for the merge window so latter will be forthcoming in the
next cycle.
- Rework the early code's position-dependent SEV variable references in
order to allow building the kernel with clang and -fPIE/-fPIC and
-mcmodel=kernel
- The usual set of fixes, cleanups and improvements all over the place
* tag 'x86_sev_for_v6.9_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (36 commits)
x86/sev: Disable KMSAN for memory encryption TUs
x86/sev: Dump SEV_STATUS
crypto: ccp - Have it depend on AMD_IOMMU
iommu/amd: Fix failure return from snp_lookup_rmpentry()
x86/sev: Fix position dependent variable references in startup code
crypto: ccp: Make snp_range_list static
x86/Kconfig: Remove CONFIG_AMD_MEM_ENCRYPT_ACTIVE_BY_DEFAULT
Documentation: virt: Fix up pre-formatted text block for SEV ioctls
crypto: ccp: Add the SNP_SET_CONFIG command
crypto: ccp: Add the SNP_COMMIT command
crypto: ccp: Add the SNP_PLATFORM_STATUS command
x86/cpufeatures: Enable/unmask SEV-SNP CPU feature
KVM: SEV: Make AVIC backing, VMSA and VMCB memory allocation SNP safe
crypto: ccp: Add panic notifier for SEV/SNP firmware shutdown on kdump
iommu/amd: Clean up RMP entries for IOMMU pages during SNP shutdown
crypto: ccp: Handle legacy SEV commands when SNP is enabled
crypto: ccp: Handle non-volatile INIT_EX data when SNP is enabled
crypto: ccp: Handle the legacy TMR allocation when SNP is enabled
x86/sev: Introduce an SNP leaked pages list
crypto: ccp: Provide an API to issue SEV and SNP commands
...
FRED is a replacement for IDT event delivery on x86 and addresses most of
the technical nightmares which IDT exposes:
1) Exception cause registers like CR2 need to be manually preserved in
nested exception scenarios.
2) Hardware interrupt stack switching is suboptimal for nested exceptions
as the interrupt stack mechanism rewinds the stack on each entry which
requires a massive effort in the low level entry of #NMI code to handle
this.
3) No hardware distinction between entry from kernel or from user which
makes establishing kernel context more complex than it needs to be
especially for unconditionally nestable exceptions like NMI.
4) NMI nesting caused by IRET unconditionally reenabling NMIs, which is a
problem when the perf NMI takes a fault when collecting a stack trace.
5) Partial restore of ESP when returning to a 16-bit segment
6) Limitation of the vector space which can cause vector exhaustion on
large systems.
7) Inability to differentiate NMI sources
FRED addresses these shortcomings by:
1) An extended exception stack frame which the CPU uses to save exception
cause registers. This ensures that the meta information for each
exception is preserved on stack and avoids the extra complexity of
preserving it in software.
2) Hardware interrupt stack switching is non-rewinding if a nested
exception uses the currently interrupt stack.
3) The entry points for kernel and user context are separate and GS BASE
handling which is required to establish kernel context for per CPU
variable access is done in hardware.
4) NMIs are now nesting protected. They are only reenabled on the return
from NMI.
5) FRED guarantees full restore of ESP
6) FRED does not put a limitation on the vector space by design because it
uses a central entry points for kernel and user space and the CPUstores
the entry type (exception, trap, interrupt, syscall) on the entry stack
along with the vector number. The entry code has to demultiplex this
information, but this removes the vector space restriction.
The first hardware implementations will still have the current
restricted vector space because lifting this limitation requires
further changes to the local APIC.
7) FRED stores the vector number and meta information on stack which
allows having more than one NMI vector in future hardware when the
required local APIC changes are in place.
The series implements the initial FRED support by:
- Reworking the existing entry and IDT handling infrastructure to
accomodate for the alternative entry mechanism.
- Expanding the stack frame to accomodate for the extra 16 bytes FRED
requires to store context and meta information
- Providing FRED specific C entry points for events which have information
pushed to the extended stack frame, e.g. #PF and #DB.
- Providing FRED specific C entry points for #NMI and #MCE
- Implementing the FRED specific ASM entry points and the C code to
demultiplex the events
- Providing detection and initialization mechanisms and the necessary
tweaks in context switching, GS BASE handling etc.
The FRED integration aims for maximum code reuse vs. the existing IDT
implementation to the extent possible and the deviation in hot paths like
context switching are handled with alternatives to minimalize the
impact. The low level entry and exit paths are seperate due to the extended
stack frame and the hardware based GS BASE swichting and therefore have no
impact on IDT based systems.
It has been extensively tested on existing systems and on the FRED
simulation and as of now there are know outstanding problems.
-----BEGIN PGP SIGNATURE-----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=Ib7w
-----END PGP SIGNATURE-----
Merge tag 'x86-fred-2024-03-10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 FRED support from Thomas Gleixner:
"Support for x86 Fast Return and Event Delivery (FRED).
FRED is a replacement for IDT event delivery on x86 and addresses most
of the technical nightmares which IDT exposes:
1) Exception cause registers like CR2 need to be manually preserved
in nested exception scenarios.
2) Hardware interrupt stack switching is suboptimal for nested
exceptions as the interrupt stack mechanism rewinds the stack on
each entry which requires a massive effort in the low level entry
of #NMI code to handle this.
3) No hardware distinction between entry from kernel or from user
which makes establishing kernel context more complex than it needs
to be especially for unconditionally nestable exceptions like NMI.
4) NMI nesting caused by IRET unconditionally reenabling NMIs, which
is a problem when the perf NMI takes a fault when collecting a
stack trace.
5) Partial restore of ESP when returning to a 16-bit segment
6) Limitation of the vector space which can cause vector exhaustion
on large systems.
7) Inability to differentiate NMI sources
FRED addresses these shortcomings by:
1) An extended exception stack frame which the CPU uses to save
exception cause registers. This ensures that the meta information
for each exception is preserved on stack and avoids the extra
complexity of preserving it in software.
2) Hardware interrupt stack switching is non-rewinding if a nested
exception uses the currently interrupt stack.
3) The entry points for kernel and user context are separate and GS
BASE handling which is required to establish kernel context for
per CPU variable access is done in hardware.
4) NMIs are now nesting protected. They are only reenabled on the
return from NMI.
5) FRED guarantees full restore of ESP
6) FRED does not put a limitation on the vector space by design
because it uses a central entry points for kernel and user space
and the CPUstores the entry type (exception, trap, interrupt,
syscall) on the entry stack along with the vector number. The
entry code has to demultiplex this information, but this removes
the vector space restriction.
The first hardware implementations will still have the current
restricted vector space because lifting this limitation requires
further changes to the local APIC.
7) FRED stores the vector number and meta information on stack which
allows having more than one NMI vector in future hardware when the
required local APIC changes are in place.
The series implements the initial FRED support by:
- Reworking the existing entry and IDT handling infrastructure to
accomodate for the alternative entry mechanism.
- Expanding the stack frame to accomodate for the extra 16 bytes FRED
requires to store context and meta information
- Providing FRED specific C entry points for events which have
information pushed to the extended stack frame, e.g. #PF and #DB.
- Providing FRED specific C entry points for #NMI and #MCE
- Implementing the FRED specific ASM entry points and the C code to
demultiplex the events
- Providing detection and initialization mechanisms and the necessary
tweaks in context switching, GS BASE handling etc.
The FRED integration aims for maximum code reuse vs the existing IDT
implementation to the extent possible and the deviation in hot paths
like context switching are handled with alternatives to minimalize the
impact. The low level entry and exit paths are seperate due to the
extended stack frame and the hardware based GS BASE swichting and
therefore have no impact on IDT based systems.
It has been extensively tested on existing systems and on the FRED
simulation and as of now there are no outstanding problems"
* tag 'x86-fred-2024-03-10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (38 commits)
x86/fred: Fix init_task thread stack pointer initialization
MAINTAINERS: Add a maintainer entry for FRED
x86/fred: Fix a build warning with allmodconfig due to 'inline' failing to inline properly
x86/fred: Invoke FRED initialization code to enable FRED
x86/fred: Add FRED initialization functions
x86/syscall: Split IDT syscall setup code into idt_syscall_init()
KVM: VMX: Call fred_entry_from_kvm() for IRQ/NMI handling
x86/entry: Add fred_entry_from_kvm() for VMX to handle IRQ/NMI
x86/entry/calling: Allow PUSH_AND_CLEAR_REGS being used beyond actual entry code
x86/fred: Fixup fault on ERETU by jumping to fred_entrypoint_user
x86/fred: Let ret_from_fork_asm() jmp to asm_fred_exit_user when FRED is enabled
x86/traps: Add sysvec_install() to install a system interrupt handler
x86/fred: FRED entry/exit and dispatch code
x86/fred: Add a machine check entry stub for FRED
x86/fred: Add a NMI entry stub for FRED
x86/fred: Add a debug fault entry stub for FRED
x86/idtentry: Incorporate definitions/declarations of the FRED entries
x86/fred: Make exc_page_fault() work for FRED
x86/fred: Allow single-step trap and NMI when starting a new task
x86/fred: No ESPFIX needed when FRED is enabled
...
The current implementation has a couple of shortcomings:
- It fails to handle hybrid systems correctly.
- The APIC registration code which handles CPU number assignents is in
the middle of the APIC code and detached from the topology evaluation.
- The various mechanisms which enumerate APICs, ACPI, MPPARSE and guest
specific ones, tweak global variables as they see fit or in case of
XENPV just hack around the generic mechanisms completely.
- The CPUID topology evaluation code is sprinkled all over the vendor
code and reevaluates global variables on every hotplug operation.
- There is no way to analyze topology on the boot CPU before bringing up
the APs. This causes problems for infrastructure like PERF which needs
to size certain aspects upfront or could be simplified if that would be
possible.
- The APIC admission and CPU number association logic is incomprehensible
and overly complex and needs to be kept around after boot instead of
completing this right after the APIC enumeration.
This update addresses these shortcomings with the following changes:
- Rework the CPUID evaluation code so it is common for all vendors and
provides information about the APIC ID segments in a uniform way
independent of the number of segments (Thread, Core, Module, ..., Die,
Package) so that this information can be computed instead of rewriting
global variables of dubious value over and over.
- A few cleanups and simplifcations of the APIC, IO/APIC and related
interfaces to prepare for the topology evaluation changes.
- Seperation of the parser stages so the early evaluation which tries to
find the APIC address can be seperately overridden from the late
evaluation which enumerates and registers the local APIC as further
preparation for sanitizing the topology evaluation.
- A new registration and admission logic which
- encapsulates the inner workings so that parsers and guest logic
cannot longer fiddle in it
- uses the APIC ID segments to build topology bitmaps at registration
time
- provides a sane admission logic
- allows to detect the crash kernel case, where CPU0 does not run on
the real BSP, automatically. This is required to prevent sending
INIT/SIPI sequences to the real BSP which would reset the whole
machine. This was so far handled by a tedious command line
parameter, which does not even work in nested crash scenarios.
- Associates CPU number after the enumeration completed and prevents
the late registration of APICs, which was somehow tolerated before.
- Converting all parsers and guest enumeration mechanisms over to the
new interfaces.
This allows to get rid of all global variable tweaking from the parsers
and enumeration mechanisms and sanitizes the XEN[PV] handling so it can
use CPUID evaluation for the first time.
- Mopping up existing sins by taking the information from the APIC ID
segment bitmaps.
This evaluates hybrid systems correctly on the boot CPU and allows for
cleanups and fixes in the related drivers, e.g. PERF.
The series has been extensively tested and the minimal late fallout due to
a broken ACPI/MADT table has been addressed by tightening the admission
logic further.
-----BEGIN PGP SIGNATURE-----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=/5oR
-----END PGP SIGNATURE-----
Merge tag 'x86-apic-2024-03-10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 APIC updates from Thomas Gleixner:
"Rework of APIC enumeration and topology evaluation.
The current implementation has a couple of shortcomings:
- It fails to handle hybrid systems correctly.
- The APIC registration code which handles CPU number assignents is
in the middle of the APIC code and detached from the topology
evaluation.
- The various mechanisms which enumerate APICs, ACPI, MPPARSE and
guest specific ones, tweak global variables as they see fit or in
case of XENPV just hack around the generic mechanisms completely.
- The CPUID topology evaluation code is sprinkled all over the vendor
code and reevaluates global variables on every hotplug operation.
- There is no way to analyze topology on the boot CPU before bringing
up the APs. This causes problems for infrastructure like PERF which
needs to size certain aspects upfront or could be simplified if
that would be possible.
- The APIC admission and CPU number association logic is
incomprehensible and overly complex and needs to be kept around
after boot instead of completing this right after the APIC
enumeration.
This update addresses these shortcomings with the following changes:
- Rework the CPUID evaluation code so it is common for all vendors
and provides information about the APIC ID segments in a uniform
way independent of the number of segments (Thread, Core, Module,
..., Die, Package) so that this information can be computed instead
of rewriting global variables of dubious value over and over.
- A few cleanups and simplifcations of the APIC, IO/APIC and related
interfaces to prepare for the topology evaluation changes.
- Seperation of the parser stages so the early evaluation which tries
to find the APIC address can be seperately overridden from the late
evaluation which enumerates and registers the local APIC as further
preparation for sanitizing the topology evaluation.
- A new registration and admission logic which
- encapsulates the inner workings so that parsers and guest logic
cannot longer fiddle in it
- uses the APIC ID segments to build topology bitmaps at
registration time
- provides a sane admission logic
- allows to detect the crash kernel case, where CPU0 does not run
on the real BSP, automatically. This is required to prevent
sending INIT/SIPI sequences to the real BSP which would reset
the whole machine. This was so far handled by a tedious command
line parameter, which does not even work in nested crash
scenarios.
- Associates CPU number after the enumeration completed and
prevents the late registration of APICs, which was somehow
tolerated before.
- Converting all parsers and guest enumeration mechanisms over to the
new interfaces.
This allows to get rid of all global variable tweaking from the
parsers and enumeration mechanisms and sanitizes the XEN[PV]
handling so it can use CPUID evaluation for the first time.
- Mopping up existing sins by taking the information from the APIC ID
segment bitmaps.
This evaluates hybrid systems correctly on the boot CPU and allows
for cleanups and fixes in the related drivers, e.g. PERF.
The series has been extensively tested and the minimal late fallout
due to a broken ACPI/MADT table has been addressed by tightening the
admission logic further"
* tag 'x86-apic-2024-03-10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (76 commits)
x86/topology: Ignore non-present APIC IDs in a present package
x86/apic: Build the x86 topology enumeration functions on UP APIC builds too
smp: Provide 'setup_max_cpus' definition on UP too
smp: Avoid 'setup_max_cpus' namespace collision/shadowing
x86/bugs: Use fixed addressing for VERW operand
x86/cpu/topology: Get rid of cpuinfo::x86_max_cores
x86/cpu/topology: Provide __num_[cores|threads]_per_package
x86/cpu/topology: Rename topology_max_die_per_package()
x86/cpu/topology: Rename smp_num_siblings
x86/cpu/topology: Retrieve cores per package from topology bitmaps
x86/cpu/topology: Use topology logical mapping mechanism
x86/cpu/topology: Provide logical pkg/die mapping
x86/cpu/topology: Simplify cpu_mark_primary_thread()
x86/cpu/topology: Mop up primary thread mask handling
x86/cpu/topology: Use topology bitmaps for sizing
x86/cpu/topology: Let XEN/PV use topology from CPUID/MADT
x86/xen/smp_pv: Count number of vCPUs early
x86/cpu/topology: Assign hotpluggable CPUIDs during init
x86/cpu/topology: Reject unknown APIC IDs on ACPI hotplug
x86/topology: Add a mechanism to track topology via APIC IDs
...
- The hierarchical timer pull model
When timer wheel timers are armed they are placed into the timer wheel
of a CPU which is likely to be busy at the time of expiry. This is done
to avoid wakeups on potentially idle CPUs.
This is wrong in several aspects:
1) The heuristics to select the target CPU are wrong by
definition as the chance to get the prediction right is close
to zero.
2) Due to #1 it is possible that timers are accumulated on a
single target CPU
3) The required computation in the enqueue path is just overhead for
dubious value especially under the consideration that the vast
majority of timer wheel timers are either canceled or rearmed
before they expire.
The timer pull model avoids the above by removing the target
computation on enqueue and queueing timers always on the CPU on which
they get armed.
This is achieved by having separate wheels for CPU pinned timers and
global timers which do not care about where they expire.
As long as a CPU is busy it handles both the pinned and the global
timers which are queued on the CPU local timer wheels.
When a CPU goes idle it evaluates its own timer wheels:
- If the first expiring timer is a pinned timer, then the global
timers can be ignored as the CPU will wake up before they expire.
- If the first expiring timer is a global timer, then the expiry time
is propagated into the timer pull hierarchy and the CPU makes sure
to wake up for the first pinned timer.
The timer pull hierarchy organizes CPUs in groups of eight at the
lowest level and at the next levels groups of eight groups up to the
point where no further aggregation of groups is required, i.e. the
number of levels is log8(NR_CPUS). The magic number of eight has been
established by experimention, but can be adjusted if needed.
In each group one busy CPU acts as the migrator. It's only one CPU to
avoid lock contention on remote timer wheels.
The migrator CPU checks in its own timer wheel handling whether there
are other CPUs in the group which have gone idle and have global timers
to expire. If there are global timers to expire, the migrator locks the
remote CPU timer wheel and handles the expiry.
Depending on the group level in the hierarchy this handling can require
to walk the hierarchy downwards to the CPU level.
Special care is taken when the last CPU goes idle. At this point the
CPU is the systemwide migrator at the top of the hierarchy and it
therefore cannot delegate to the hierarchy. It needs to arm its own
timer device to expire either at the first expiring timer in the
hierarchy or at the first CPU local timer, which ever expires first.
This completely removes the overhead from the enqueue path, which is
e.g. for networking a true hotpath and trades it for a slightly more
complex idle path.
This has been in development for a couple of years and the final series
has been extensively tested by various teams from silicon vendors and
ran through extensive CI.
There have been slight performance improvements observed on network
centric workloads and an Intel team confirmed that this allows them to
power down a die completely on a mult-die socket for the first time in
a mostly idle scenario.
There is only one outstanding ~1.5% regression on a specific overloaded
netperf test which is currently investigated, but the rest is either
positive or neutral performance wise and positive on the power
management side.
- Fixes for the timekeeping interpolation code for cross-timestamps:
cross-timestamps are used for PTP to get snapshots from hardware timers
and interpolated them back to clock MONOTONIC. The changes address a
few corner cases in the interpolation code which got the math and logic
wrong.
- Simplifcation of the clocksource watchdog retry logic to automatically
adjust to handle larger systems correctly instead of having more
incomprehensible command line parameters.
- Treewide consolidation of the VDSO data structures.
- The usual small improvements and cleanups all over the place.
-----BEGIN PGP SIGNATURE-----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=iQlu
-----END PGP SIGNATURE-----
Merge tag 'timers-core-2024-03-10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timer updates from Thomas Gleixner:
"A large set of updates and features for timers and timekeeping:
- The hierarchical timer pull model
When timer wheel timers are armed they are placed into the timer
wheel of a CPU which is likely to be busy at the time of expiry.
This is done to avoid wakeups on potentially idle CPUs.
This is wrong in several aspects:
1) The heuristics to select the target CPU are wrong by
definition as the chance to get the prediction right is
close to zero.
2) Due to #1 it is possible that timers are accumulated on
a single target CPU
3) The required computation in the enqueue path is just overhead
for dubious value especially under the consideration that the
vast majority of timer wheel timers are either canceled or
rearmed before they expire.
The timer pull model avoids the above by removing the target
computation on enqueue and queueing timers always on the CPU on
which they get armed.
This is achieved by having separate wheels for CPU pinned timers
and global timers which do not care about where they expire.
As long as a CPU is busy it handles both the pinned and the global
timers which are queued on the CPU local timer wheels.
When a CPU goes idle it evaluates its own timer wheels:
- If the first expiring timer is a pinned timer, then the global
timers can be ignored as the CPU will wake up before they
expire.
- If the first expiring timer is a global timer, then the expiry
time is propagated into the timer pull hierarchy and the CPU
makes sure to wake up for the first pinned timer.
The timer pull hierarchy organizes CPUs in groups of eight at the
lowest level and at the next levels groups of eight groups up to
the point where no further aggregation of groups is required, i.e.
the number of levels is log8(NR_CPUS). The magic number of eight
has been established by experimention, but can be adjusted if
needed.
In each group one busy CPU acts as the migrator. It's only one CPU
to avoid lock contention on remote timer wheels.
The migrator CPU checks in its own timer wheel handling whether
there are other CPUs in the group which have gone idle and have
global timers to expire. If there are global timers to expire, the
migrator locks the remote CPU timer wheel and handles the expiry.
Depending on the group level in the hierarchy this handling can
require to walk the hierarchy downwards to the CPU level.
Special care is taken when the last CPU goes idle. At this point
the CPU is the systemwide migrator at the top of the hierarchy and
it therefore cannot delegate to the hierarchy. It needs to arm its
own timer device to expire either at the first expiring timer in
the hierarchy or at the first CPU local timer, which ever expires
first.
This completely removes the overhead from the enqueue path, which
is e.g. for networking a true hotpath and trades it for a slightly
more complex idle path.
This has been in development for a couple of years and the final
series has been extensively tested by various teams from silicon
vendors and ran through extensive CI.
There have been slight performance improvements observed on network
centric workloads and an Intel team confirmed that this allows them
to power down a die completely on a mult-die socket for the first
time in a mostly idle scenario.
There is only one outstanding ~1.5% regression on a specific
overloaded netperf test which is currently investigated, but the
rest is either positive or neutral performance wise and positive on
the power management side.
- Fixes for the timekeeping interpolation code for cross-timestamps:
cross-timestamps are used for PTP to get snapshots from hardware
timers and interpolated them back to clock MONOTONIC. The changes
address a few corner cases in the interpolation code which got the
math and logic wrong.
- Simplifcation of the clocksource watchdog retry logic to
automatically adjust to handle larger systems correctly instead of
having more incomprehensible command line parameters.
- Treewide consolidation of the VDSO data structures.
- The usual small improvements and cleanups all over the place"
* tag 'timers-core-2024-03-10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (62 commits)
timer/migration: Fix quick check reporting late expiry
tick/sched: Fix build failure for CONFIG_NO_HZ_COMMON=n
vdso/datapage: Quick fix - use asm/page-def.h for ARM64
timers: Assert no next dyntick timer look-up while CPU is offline
tick: Assume timekeeping is correctly handed over upon last offline idle call
tick: Shut down low-res tick from dying CPU
tick: Split nohz and highres features from nohz_mode
tick: Move individual bit features to debuggable mask accesses
tick: Move got_idle_tick away from common flags
tick: Assume the tick can't be stopped in NOHZ_MODE_INACTIVE mode
tick: Move broadcast cancellation up to CPUHP_AP_TICK_DYING
tick: Move tick cancellation up to CPUHP_AP_TICK_DYING
tick: Start centralizing tick related CPU hotplug operations
tick/sched: Don't clear ts::next_tick again in can_stop_idle_tick()
tick/sched: Rename tick_nohz_stop_sched_tick() to tick_nohz_full_stop_tick()
tick: Use IS_ENABLED() whenever possible
tick/sched: Remove useless oneshot ifdeffery
tick/nohz: Remove duplicate between lowres and highres handlers
tick/nohz: Remove duplicate between tick_nohz_switch_to_nohz() and tick_setup_sched_timer()
hrtimer: Select housekeeping CPU during migration
...
RFDS is a CPU vulnerability that may allow userspace to infer kernel
stale data previously used in floating point registers, vector registers
and integer registers. RFDS only affects certain Intel Atom processors.
Intel released a microcode update that uses VERW instruction to clear
the affected CPU buffers. Unlike MDS, none of the affected cores support
SMT.
Add RFDS bug infrastructure and enable the VERW based mitigation by
default, that clears the affected buffers just before exiting to
userspace. Also add sysfs reporting and cmdline parameter
"reg_file_data_sampling" to control the mitigation.
For details see:
Documentation/admin-guide/hw-vuln/reg-file-data-sampling.rst
Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Josh Poimboeuf <jpoimboe@kernel.org>
This cycle, a lot of workqueue changes including some that are significant
and invasive.
- During v6.6 cycle, unbound workqueues were updated so that they are more
topology aware and flexible, which among other things improved workqueue
behavior on modern multi-L3 CPUs. In the process, 636b927eba
("workqueue: Make unbound workqueues to use per-cpu pool_workqueues")
switched unbound workqueues to use per-CPU frontend pool_workqueues as a
part of increasing front-back mapping flexibility.
An unwelcome side effect of this change was that this made max concurrency
enforcement per-CPU blowing up the maximum number of allowed concurrent
executions. I incorrectly assumed that this wouldn't cause practical
problems as most unbound workqueue users are self-regulate max
concurrency; however, there definitely are which don't (e.g. on IO paths)
and the drastic increase in the allowed max concurrency led to noticeable
perf regressions in some use cases.
This is now addressed by separating out max concurrency enforcement to a
separate struct - wq_node_nr_active - which makes @max_active consistently
mean system-wide max concurrency regardless of the number of CPUs or
(finally) NUMA nodes. This is a rather invasive and, in places, a bit
clunky; however, the clunkiness rises from the the inherent requirement to
handle the disagreement between the execution locality domain and max
concurrency enforcement domain on some modern machines. See 5797b1c189
("workqueue: Implement system-wide nr_active enforcement for unbound
workqueues") for more details.
- BH workqueue support is added. They are similar to per-CPU workqueues but
execute work items in the softirq context. This is expected to replace
tasklet. However, currently, it's missing the ability to disable and
enable work items which is needed to convert many tasklet users. To avoid
crowding this merge window too much, this will be included in the next
merge window. A separate pull request will be sent for the couple
conversion patches that are currently pending.
- Waiman plugged a long-standing hole in workqueue CPU isolation where
ordered workqueues didn't follow wq_unbound_cpumask updates. Ordered
workqueues now follow the same rules as other unbound workqueues.
- More CPU isolation improvements: Juri fixed another deficit in workqueue
isolation where unbound rescuers don't respect wq_unbound_cpumask.
Leonardo fixed delayed_work timers firing on isolated CPUs.
- Other misc changes.
-----BEGIN PGP SIGNATURE-----
iIQEABYKACwWIQTfIjM1kS57o3GsC/uxYfJx3gVYGQUCZe7JCQ4cdGpAa2VybmVs
Lm9yZwAKCRCxYfJx3gVYGcnqAP9UP8zEM1la19cilhboDumxmRWyRpV/egFOqsMP
Y5PuoAEAtsBJtQWtm5w46+y+fk3nK2ugXlQio2gH0qQcxX6SdgQ=
=/ovv
-----END PGP SIGNATURE-----
Merge tag 'wq-for-6.9' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq
Pull workqueue updates from Tejun Heo:
"This cycle, a lot of workqueue changes including some that are
significant and invasive.
- During v6.6 cycle, unbound workqueues were updated so that they are
more topology aware and flexible, which among other things improved
workqueue behavior on modern multi-L3 CPUs. In the process, commit
636b927eba ("workqueue: Make unbound workqueues to use per-cpu
pool_workqueues") switched unbound workqueues to use per-CPU
frontend pool_workqueues as a part of increasing front-back mapping
flexibility.
An unwelcome side effect of this change was that this made max
concurrency enforcement per-CPU blowing up the maximum number of
allowed concurrent executions. I incorrectly assumed that this
wouldn't cause practical problems as most unbound workqueue users
are self-regulate max concurrency; however, there definitely are
which don't (e.g. on IO paths) and the drastic increase in the
allowed max concurrency led to noticeable perf regressions in some
use cases.
This is now addressed by separating out max concurrency enforcement
to a separate struct - wq_node_nr_active - which makes @max_active
consistently mean system-wide max concurrency regardless of the
number of CPUs or (finally) NUMA nodes. This is a rather invasive
and, in places, a bit clunky; however, the clunkiness rises from
the the inherent requirement to handle the disagreement between the
execution locality domain and max concurrency enforcement domain on
some modern machines.
See commit 5797b1c189 ("workqueue: Implement system-wide
nr_active enforcement for unbound workqueues") for more details.
- BH workqueue support is added.
They are similar to per-CPU workqueues but execute work items in
the softirq context. This is expected to replace tasklet. However,
currently, it's missing the ability to disable and enable work
items which is needed to convert many tasklet users. To avoid
crowding this merge window too much, this will be included in the
next merge window. A separate pull request will be sent for the
couple conversion patches that are currently pending.
- Waiman plugged a long-standing hole in workqueue CPU isolation
where ordered workqueues didn't follow wq_unbound_cpumask updates.
Ordered workqueues now follow the same rules as other unbound
workqueues.
- More CPU isolation improvements: Juri fixed another deficit in
workqueue isolation where unbound rescuers don't respect
wq_unbound_cpumask. Leonardo fixed delayed_work timers firing on
isolated CPUs.
- Other misc changes"
* tag 'wq-for-6.9' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq: (54 commits)
workqueue: Drain BH work items on hot-unplugged CPUs
workqueue: Introduce from_work() helper for cleaner callback declarations
workqueue: Control intensive warning threshold through cmdline
workqueue: Make @flags handling consistent across set_work_data() and friends
workqueue: Remove clear_work_data()
workqueue: Factor out work_grab_pending() from __cancel_work_sync()
workqueue: Clean up enum work_bits and related constants
workqueue: Introduce work_cancel_flags
workqueue: Use variable name irq_flags for saving local irq flags
workqueue: Reorganize flush and cancel[_sync] functions
workqueue: Rename __cancel_work_timer() to __cancel_timer_sync()
workqueue: Use rcu_read_lock_any_held() instead of rcu_read_lock_held()
workqueue: Cosmetic changes
workqueue, irq_work: Build fix for !CONFIG_IRQ_WORK
workqueue: Fix queue_work_on() with BH workqueues
async: Use a dedicated unbound workqueue with raised min_active
workqueue: Implement workqueue_set_min_active()
workqueue: Fix kernel-doc comment of unplug_oldest_pwq()
workqueue: Bind unbound workqueue rescuer to wq_unbound_cpumask
kernel/workqueue: Let rescuers follow unbound wq cpumask changes
...
When CONFIG_WQ_CPU_INTENSIVE_REPORT is set, the kernel will report
the work functions which violate the intensive_threshold_us repeatedly.
And now, only when the violate times exceed 4 and is a power of 2,
the kernel warning could be triggered.
However, sometimes, even if a long work execution time occurs only once,
it may cause other work to be delayed for a long time. This may also
cause some problems sometimes.
In order to freely control the threshold of warninging, a boot argument
is added so that the user can control the warning threshold to be printed.
At the same time, keep the exponential backoff to prevent reporting too much.
By default, the warning threshold is 4.
tj: Updated kernel-parameters.txt description.
Signed-off-by: Xuewen Yan <xuewen.yan@unisoc.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
On a 8-socket server the TSC is wrongly marked as 'unstable' and disabled
during boot time on about one out of 120 boot attempts:
clocksource: timekeeping watchdog on CPU227: wd-tsc-wd excessive read-back delay of 153560ns vs. limit of 125000ns,
wd-wd read-back delay only 11440ns, attempt 3, marking tsc unstable
tsc: Marking TSC unstable due to clocksource watchdog
TSC found unstable after boot, most likely due to broken BIOS. Use 'tsc=unstable'.
sched_clock: Marking unstable (119294969739, 159204297)<-(125446229205, -5992055152)
clocksource: Checking clocksource tsc synchronization from CPU 319 to CPUs 0,99,136,180,210,542,601,896.
clocksource: Switched to clocksource hpet
The reason is that for platform with a large number of CPUs, there are
sporadic big or huge read latencies while reading the watchog/clocksource
during boot or when system is under stress work load, and the frequency and
maximum value of the latency goes up with the number of online CPUs.
The cCurrent code already has logic to detect and filter such high latency
case by reading the watchdog twice and checking the two deltas. Due to the
randomness of the latency, there is a low probabilty that the first delta
(latency) is big, but the second delta is small and looks valid. The
watchdog code retries the readouts by default twice, which is not
necessarily sufficient for systems with a large number of CPUs.
There is a command line parameter 'max_cswd_read_retries' which allows to
increase the number of retries, but that's not user friendly as it needs to
be tweaked per system. As the number of required retries is proportional to
the number of online CPUs, this parameter can be calculated at runtime.
Scale and enlarge the number of retries according to the number of online
CPUs and remove the command line parameter completely.
[ tglx: Massaged change log and comments ]
Signed-off-by: Feng Tang <feng.tang@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Jin Wang <jin1.wang@intel.com>
Tested-by: Paul E. McKenney <paulmck@kernel.org>
Reviewed-by: Waiman Long <longman@redhat.com>
Reviewed-by: Paul E. McKenney <paulmck@kernel.org>
Link: https://lore.kernel.org/r/20240221060859.1027450-1-feng.tang@intel.com
When a kdump kernel is started from a crashing CPU then there is no
guarantee that this CPU is the real boot CPU (BSP). If the kdump kernel
tries to online the BSP then the INIT sequence will reset the machine.
There is a command line option to prevent this, but in case of nested kdump
kernels this is wrong.
But that command line option is not required at all because the real
BSP is enumerated as the first CPU by firmware. Support for the only
known system which was different (Voyager) got removed long ago.
Detect whether the boot CPU APIC ID is the first APIC ID enumerated by
the firmware. If the first APIC ID enumerated is not matching the boot
CPU APIC ID then skip registering it.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Michael Kelley <mhklinux@outlook.com>
Tested-by: Sohil Mehta <sohil.mehta@intel.com>
Link: https://lore.kernel.org/r/20240213210252.348542071@linutronix.de
To allow more flexible arrangements while still provide a single kernel
for distros, provide a boot time parameter to enable/disable lazy RCU.
Specify:
rcutree.enable_rcu_lazy=[y|1|n|0]
Which also requires
rcu_nocbs=all
at boot time to enable/disable lazy RCU.
To disable it by default at build time when CONFIG_RCU_LAZY=y, the new
CONFIG_RCU_LAZY_DEFAULT_OFF can be used.
Signed-off-by: Qais Yousef (Google) <qyousef@layalina.io>
Tested-by: Andrea Righi <andrea.righi@canonical.com>
Reviewed-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
Kernel boot parameters declared with early_param() are parsed before
embedded parameters are extracted from initrd, and early_param()
parameters are not helpful when embedded in initrd. Therefore,
mark early_param() kernel boot parameters with "EARLY" in
kernel-parameters.txt.
The following early_param() calls declare kernel boot parameters that
are undocumented:
early_param("atmel.pm_modes", at91_pm_modes_select);
early_param("mem_fclk_21285", early_fclk);
early_param("ecc", early_ecc);
early_param("cachepolicy", early_cachepolicy);
early_param("nodebugmon", early_debug_disable);
early_param("kfence.sample_interval", parse_kfence_early_init);
early_param("additional_cpus", setup_additional_cpus);
early_param("stram_pool", atari_stram_setup);
early_param("disable_octeon_edac", disable_octeon_edac);
early_param("rd_start", rd_start_early);
early_param("rd_size", rd_size_early);
early_param("coherentio", setcoherentio);
early_param("nocoherentio", setnocoherentio);
early_param("fadump", early_fadump_param);
early_param("fadump_reserve_mem", early_fadump_reserve_mem);
early_param("no_stf_barrier", handle_no_stf_barrier);
early_param("no_rfi_flush", handle_no_rfi_flush);
early_param("smt-enabled", early_smt_enabled);
early_param("ppc_pci_reset_phbs", pci_reset_phbs_setup);
early_param("ps3fb", early_parse_ps3fb);
early_param("ps3flash", early_parse_ps3flash);
early_param("novx", disable_vector_extension);
early_param("nobp", nobp_setup_early);
early_param("nospec", nospec_setup_early);
early_param("possible_cpus", _setup_possible_cpus);
early_param("stp", early_parse_stp);
early_param("nopfault", nopfault);
early_param("nmi_mode", nmi_mode_setup);
early_param("sh_mv", early_parse_mv);
early_param("pmb", early_pmb);
early_param("hvirq", early_hvirq_major);
early_param("cfi", cfi_parse_cmdline);
early_param("disableapic", setup_disableapic);
early_param("noapictimer", parse_disable_apic_timer);
early_param("disable_cpu_apicid", apic_set_disabled_cpu_apicid);
early_param("uv_memblksize", parse_mem_block_size);
early_param("retbleed", retbleed_parse_cmdline);
early_param("no-kvmclock-vsyscall", parse_no_kvmclock_vsyscall);
early_param("update_mptable", update_mptable_setup);
early_param("alloc_mptable", parse_alloc_mptable_opt);
early_param("possible_cpus", _setup_possible_cpus);
early_param("lsmsi", early_parse_ls_scfg_msi);
early_param("nokgdbroundup", opt_nokgdbroundup);
early_param("kgdbcon", opt_kgdb_con);
early_param("kasan", early_kasan_flag);
early_param("kasan.mode", early_kasan_mode);
early_param("kasan.vmalloc", early_kasan_flag_vmalloc);
early_param("kasan.page_alloc.sample", early_kasan_flag_page_alloc_sample);
early_param("kasan.page_alloc.sample.order", early_kasan_flag_page_alloc_sample_order);
early_param("kasan.fault", early_kasan_fault);
early_param("kasan.stacktrace", early_kasan_flag_stacktrace);
early_param("kasan.stack_ring_size", early_kasan_flag_stack_ring_size);
early_param("accept_memory", accept_memory_parse);
early_param("page_table_check", early_page_table_check_param);
sh_early_platform_init("earlytimer", &sh_cmt_device_driver);
early_param_on_off("gbpages", "nogbpages", direct_gbpages, CONFIG_X86_DIRECT_GBPAGES);
These are not necessarily bugs, given that some kernel boot parameters
are intended for deep debugging rather than general use.
This work does not cover all of the kernel boot parameters declared using
cmdline_find_option() and cmdline_find_option_bool(). If these are in
fact guaranteed to be early (which appears to be the case), they can be
added in a later version of this patch.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Petr Malat <oss@malat.biz>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: <linux-doc@vger.kernel.org>
Cc: <linux-arch@vger.kernel.org>
Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
The number of possible CPUs is set be kernel in early boot time through
some discovery mechanisms, like ACPI in x86. We have a parameter both
in x86 and S390 to override that - there are some cases of BIOSes exposing
more possible CPUs than the available ones, so this parameter is a good
testing mechanism, but for some reason wasn't mentioned so far in the
kernel parameters guide - let's fix that.
Cc: Changwoo Min <changwoo@igalia.com>
Signed-off-by: "Guilherme G. Piccoli" <gpiccoli@igalia.com>
Reviewed-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Link: https://lore.kernel.org/r/20240203152208.1461293-1-gpiccoli@igalia.com
Let command line option "fred" accept multiple options to make it
easier to tweak its behavior.
Currently, two options 'on' and 'off' are allowed, and the default
behavior is to disable FRED. To enable FRED, append "fred=on" to the
kernel command line.
[ bp: Use cpu_feature_enabled(), touch ups. ]
Signed-off-by: Xin Li <xin3.li@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Tested-by: Shan Kang <shan.kang@intel.com>
Link: https://lore.kernel.org/r/20231205105030.8698-9-xin3.li@intel.com
1, Raise minimum clang version to 18.0.0;
2, Enable initial Rust support for LoongArch;
3, Add built-in dtb support for LoongArch;
4, Use generic interface to support crashkernel=X,[high,low];
5, Some bug fixes and other small changes;
6, Update the default config file.
-----BEGIN PGP SIGNATURE-----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=GzFR
-----END PGP SIGNATURE-----
Merge tag 'loongarch-6.8' of git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson
Pull LoongArch updates from Huacai Chen:
- Raise minimum clang version to 18.0.0
- Enable initial Rust support for LoongArch
- Add built-in dtb support for LoongArch
- Use generic interface to support crashkernel=X,[high,low]
- Some bug fixes and other small changes
- Update the default config file.
* tag 'loongarch-6.8' of git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson: (22 commits)
MAINTAINERS: Add BPF JIT for LOONGARCH entry
LoongArch: Update Loongson-3 default config file
LoongArch: BPF: Prevent out-of-bounds memory access
LoongArch: BPF: Support 64-bit pointers to kfuncs
LoongArch: Fix definition of ftrace_regs_set_instruction_pointer()
LoongArch: Use generic interface to support crashkernel=X,[high,low]
LoongArch: Fix and simplify fcsr initialization on execve()
LoongArch: Let cores_io_master cover the largest NR_CPUS
LoongArch: Change SHMLBA from SZ_64K to PAGE_SIZE
LoongArch: Add a missing call to efi_esrt_init()
LoongArch: Parsing CPU-related information from DTS
LoongArch: dts: DeviceTree for Loongson-2K2000
LoongArch: dts: DeviceTree for Loongson-2K1000
LoongArch: dts: DeviceTree for Loongson-2K0500
LoongArch: Allow device trees be built into the kernel
dt-bindings: interrupt-controller: loongson,liointc: Fix dtbs_check warning for interrupt-names
dt-bindings: interrupt-controller: loongson,liointc: Fix dtbs_check warning for reg-names
dt-bindings: loongarch: Add Loongson SoC boards compatibles
dt-bindings: loongarch: Add CPU bindings for LoongArch
LoongArch: Enable initial Rust support
...
Here is the big set of USB and Thunderbolt changes for 6.8-rc1.
Included in here are the following:
- Thunderbolt subsystem and driver updates for USB 4 hardware and
issues reported by real devices
- xhci driver updates
- dwc3 driver updates
- uvc_video gadget driver updates
- typec driver updates
- gadget string functions cleaned up
- other small changes
All of these have been in the linux-next tree for a while with no
reported issues.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-----BEGIN PGP SIGNATURE-----
iG0EABECAC0WIQT0tgzFv3jCIUoxPcsxR9QN2y37KQUCZaedng8cZ3JlZ0Brcm9h
aC5jb20ACgkQMUfUDdst+yndHACfX3SA2ipK5umpMsWOoLMCBV6VyrwAn3t+FPd/
z4mNiCuNUhbEnU7RinK0
=k/E9
-----END PGP SIGNATURE-----
Merge tag 'usb-6.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb
Pull USB / Thunderbolt updates from Greg KH:
"Here is the big set of USB and Thunderbolt changes for 6.8-rc1.
Included in here are the following:
- Thunderbolt subsystem and driver updates for USB 4 hardware and
issues reported by real devices
- xhci driver updates
- dwc3 driver updates
- uvc_video gadget driver updates
- typec driver updates
- gadget string functions cleaned up
- other small changes
All of these have been in the linux-next tree for a while with no
reported issues"
* tag 'usb-6.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (169 commits)
usb: typec: tipd: fix use of device-specific init function
usb: typec: tipd: Separate reset for TPS6598x
usb: mon: Fix atomicity violation in mon_bin_vma_fault
usb: gadget: uvc: Remove nested locking
usb: gadget: uvc: Fix use are free during STREAMOFF
usb: typec: class: fix typec_altmode_put_partner to put plugs
dt-bindings: usb: dwc3: Limit num-hc-interrupters definition
dt-bindings: usb: xhci: Add num-hc-interrupters definition
xhci: add support to allocate several interrupters
USB: core: Use device_driver directly in struct usb_driver and usb_device_driver
arm64: dts: mediatek: mt8195: Add 'rx-fifo-depth' for cherry
usb: xhci-mtk: fix a short packet issue of gen1 isoc-in transfer
dt-bindings: usb: mtk-xhci: add a property for Gen1 isoc-in transfer issue
arm64: dts: qcom: msm8996: Remove PNoC clock from MSS
arm64: dts: qcom: msm8996: Remove AGGRE2 clock from SLPI
arm64: dts: qcom: msm8998: Remove AGGRE2 clock from SLPI
arm64: dts: qcom: msm8939: Drop RPM bus clocks
arm64: dts: qcom: sdm630: Drop RPM bus clocks
arm64: dts: qcom: qcs404: Drop RPM bus clocks
arm64: dts: qcom: msm8996: Drop RPM bus clocks
...
Here are the set of driver core and kernfs changes for 6.8-rc1. Nothing
major in here this release cycle, just lots of small cleanups and some
tweaks on kernfs that in the very end, got reverted and will come back
in a safer way next release cycle.
Included in here are:
- more driver core 'const' cleanups and fixes
- fw_devlink=rpm is now the default behavior
- kernfs tiny changes to remove some string functions
- cpu handling in the driver core is updated to work better on many
systems that add topologies and cpus after booting
- other minor changes and cleanups
All of the cpu handling patches have been acked by the respective
maintainers and are coming in here in one series. Everything has been
in linux-next for a while with no reported issues.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-----BEGIN PGP SIGNATURE-----
iG0EABECAC0WIQT0tgzFv3jCIUoxPcsxR9QN2y37KQUCZaeOrg8cZ3JlZ0Brcm9h
aC5jb20ACgkQMUfUDdst+ymtcwCffzvKKkSY9qAp6+0v2WQNkZm1JWoAoJCPYUwF
If6wEoPLWvRfKx4gIoq9
=D96r
-----END PGP SIGNATURE-----
Merge tag 'driver-core-6.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
Pull driver core updates from Greg KH:
"Here are the set of driver core and kernfs changes for 6.8-rc1.
Nothing major in here this release cycle, just lots of small cleanups
and some tweaks on kernfs that in the very end, got reverted and will
come back in a safer way next release cycle.
Included in here are:
- more driver core 'const' cleanups and fixes
- fw_devlink=rpm is now the default behavior
- kernfs tiny changes to remove some string functions
- cpu handling in the driver core is updated to work better on many
systems that add topologies and cpus after booting
- other minor changes and cleanups
All of the cpu handling patches have been acked by the respective
maintainers and are coming in here in one series. Everything has been
in linux-next for a while with no reported issues"
* tag 'driver-core-6.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (51 commits)
Revert "kernfs: convert kernfs_idr_lock to an irq safe raw spinlock"
kernfs: convert kernfs_idr_lock to an irq safe raw spinlock
class: fix use-after-free in class_register()
PM: clk: make pm_clk_add_notifier() take a const pointer
EDAC: constantify the struct bus_type usage
kernfs: fix reference to renamed function
driver core: device.h: fix Excess kernel-doc description warning
driver core: class: fix Excess kernel-doc description warning
driver core: mark remaining local bus_type variables as const
driver core: container: make container_subsys const
driver core: bus: constantify subsys_register() calls
driver core: bus: make bus_sort_breadthfirst() take a const pointer
kernfs: d_obtain_alias(NULL) will do the right thing...
driver core: Better advertise dev_err_probe()
kernfs: Convert kernfs_path_from_node_locked() from strlcpy() to strscpy()
kernfs: Convert kernfs_name_locked() from strlcpy() to strscpy()
kernfs: Convert kernfs_walk_ns() from strlcpy() to strscpy()
initramfs: Expose retained initrd as sysfs file
fs/kernfs/dir: obey S_ISGID
kernel/cgroup: use kernfs_create_dir_ns()
...
- Use memdup_array_user() to harden against overflow.
- Unconditionally advertise KVM_CAP_DEVICE_CTRL for all architectures.
- Clean up Kconfigs that all KVM architectures were selecting
- New functionality around "guest_memfd", a new userspace API that
creates an anonymous file and returns a file descriptor that refers
to it. guest_memfd files are bound to their owning virtual machine,
cannot be mapped, read, or written by userspace, and cannot be resized.
guest_memfd files do however support PUNCH_HOLE, which can be used to
switch a memory area between guest_memfd and regular anonymous memory.
- New ioctl KVM_SET_MEMORY_ATTRIBUTES allowing userspace to specify
per-page attributes for a given page of guest memory; right now the
only attribute is whether the guest expects to access memory via
guest_memfd or not, which in Confidential SVMs backed by SEV-SNP,
TDX or ARM64 pKVM is checked by firmware or hypervisor that guarantees
confidentiality (AMD PSP, Intel TDX module, or EL2 in the case of pKVM).
x86:
- Support for "software-protected VMs" that can use the new guest_memfd
and page attributes infrastructure. This is mostly useful for testing,
since there is no pKVM-like infrastructure to provide a meaningfully
reduced TCB.
- Fix a relatively benign off-by-one error when splitting huge pages during
CLEAR_DIRTY_LOG.
- Fix a bug where KVM could incorrectly test-and-clear dirty bits in non-leaf
TDP MMU SPTEs if a racing thread replaces a huge SPTE with a non-huge SPTE.
- Use more generic lockdep assertions in paths that don't actually care
about whether the caller is a reader or a writer.
- let Xen guests opt out of having PV clock reported as "based on a stable TSC",
because some of them don't expect the "TSC stable" bit (added to the pvclock
ABI by KVM, but never set by Xen) to be set.
- Revert a bogus, made-up nested SVM consistency check for TLB_CONTROL.
- Advertise flush-by-ASID support for nSVM unconditionally, as KVM always
flushes on nested transitions, i.e. always satisfies flush requests. This
allows running bleeding edge versions of VMware Workstation on top of KVM.
- Sanity check that the CPU supports flush-by-ASID when enabling SEV support.
- On AMD machines with vNMI, always rely on hardware instead of intercepting
IRET in some cases to detect unmasking of NMIs
- Support for virtualizing Linear Address Masking (LAM)
- Fix a variety of vPMU bugs where KVM fail to stop/reset counters and other state
prior to refreshing the vPMU model.
- Fix a double-overflow PMU bug by tracking emulated counter events using a
dedicated field instead of snapshotting the "previous" counter. If the
hardware PMC count triggers overflow that is recognized in the same VM-Exit
that KVM manually bumps an event count, KVM would pend PMIs for both the
hardware-triggered overflow and for KVM-triggered overflow.
- Turn off KVM_WERROR by default for all configs so that it's not
inadvertantly enabled by non-KVM developers, which can be problematic for
subsystems that require no regressions for W=1 builds.
- Advertise all of the host-supported CPUID bits that enumerate IA32_SPEC_CTRL
"features".
- Don't force a masterclock update when a vCPU synchronizes to the current TSC
generation, as updating the masterclock can cause kvmclock's time to "jump"
unexpectedly, e.g. when userspace hotplugs a pre-created vCPU.
- Use RIP-relative address to read kvm_rebooting in the VM-Enter fault paths,
partly as a super minor optimization, but mostly to make KVM play nice with
position independent executable builds.
- Guard KVM-on-HyperV's range-based TLB flush hooks with an #ifdef on
CONFIG_HYPERV as a minor optimization, and to self-document the code.
- Add CONFIG_KVM_HYPERV to allow disabling KVM support for HyperV "emulation"
at build time.
ARM64:
- LPA2 support, adding 52bit IPA/PA capability for 4kB and 16kB
base granule sizes. Branch shared with the arm64 tree.
- Large Fine-Grained Trap rework, bringing some sanity to the
feature, although there is more to come. This comes with
a prefix branch shared with the arm64 tree.
- Some additional Nested Virtualization groundwork, mostly
introducing the NV2 VNCR support and retargetting the NV
support to that version of the architecture.
- A small set of vgic fixes and associated cleanups.
Loongarch:
- Optimization for memslot hugepage checking
- Cleanup and fix some HW/SW timer issues
- Add LSX/LASX (128bit/256bit SIMD) support
RISC-V:
- KVM_GET_REG_LIST improvement for vector registers
- Generate ISA extension reg_list using macros in get-reg-list selftest
- Support for reporting steal time along with selftest
s390:
- Bugfixes
Selftests:
- Fix an annoying goof where the NX hugepage test prints out garbage
instead of the magic token needed to run the test.
- Fix build errors when a header is delete/moved due to a missing flag
in the Makefile.
- Detect if KVM bugged/killed a selftest's VM and print out a helpful
message instead of complaining that a random ioctl() failed.
- Annotate the guest printf/assert helpers with __printf(), and fix the
various bugs that were lurking due to lack of said annotation.
There are two non-KVM patches buried in the middle of guest_memfd support:
fs: Rename anon_inode_getfile_secure() and anon_inode_getfd_secure()
mm: Add AS_UNMOVABLE to mark mapping as completely unmovable
The first is small and mostly suggested-by Christian Brauner; the second
a bit less so but it was written by an mm person (Vlastimil Babka).
-----BEGIN PGP SIGNATURE-----
iQFIBAABCAAyFiEE8TM4V0tmI4mGbHaCv/vSX3jHroMFAmWcMWkUHHBib256aW5p
QHJlZGhhdC5jb20ACgkQv/vSX3jHroO15gf/WLmmg3SET6Uzw9iEq2xo28831ZA+
6kpILfIDGKozV5safDmMvcInlc/PTnqOFrsKyyN4kDZ+rIJiafJdg/loE0kPXBML
wdR+2ix5kYI1FucCDaGTahskBDz8Lb/xTpwGg9BFLYFNmuUeHc74o6GoNvr1uliE
4kLZL2K6w0cSMPybUD+HqGaET80ZqPwecv+s1JL+Ia0kYZJONJifoHnvOUJ7DpEi
rgudVdgzt3EPjG0y1z6MjvDBXTCOLDjXajErlYuZD3Ej8N8s59Dh2TxOiDNTLdP4
a4zjRvDmgyr6H6sz+upvwc7f4M4p+DBvf+TkWF54mbeObHUYliStqURIoA==
=66Ws
-----END PGP SIGNATURE-----
Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull kvm updates from Paolo Bonzini:
"Generic:
- Use memdup_array_user() to harden against overflow.
- Unconditionally advertise KVM_CAP_DEVICE_CTRL for all
architectures.
- Clean up Kconfigs that all KVM architectures were selecting
- New functionality around "guest_memfd", a new userspace API that
creates an anonymous file and returns a file descriptor that refers
to it. guest_memfd files are bound to their owning virtual machine,
cannot be mapped, read, or written by userspace, and cannot be
resized. guest_memfd files do however support PUNCH_HOLE, which can
be used to switch a memory area between guest_memfd and regular
anonymous memory.
- New ioctl KVM_SET_MEMORY_ATTRIBUTES allowing userspace to specify
per-page attributes for a given page of guest memory; right now the
only attribute is whether the guest expects to access memory via
guest_memfd or not, which in Confidential SVMs backed by SEV-SNP,
TDX or ARM64 pKVM is checked by firmware or hypervisor that
guarantees confidentiality (AMD PSP, Intel TDX module, or EL2 in
the case of pKVM).
x86:
- Support for "software-protected VMs" that can use the new
guest_memfd and page attributes infrastructure. This is mostly
useful for testing, since there is no pKVM-like infrastructure to
provide a meaningfully reduced TCB.
- Fix a relatively benign off-by-one error when splitting huge pages
during CLEAR_DIRTY_LOG.
- Fix a bug where KVM could incorrectly test-and-clear dirty bits in
non-leaf TDP MMU SPTEs if a racing thread replaces a huge SPTE with
a non-huge SPTE.
- Use more generic lockdep assertions in paths that don't actually
care about whether the caller is a reader or a writer.
- let Xen guests opt out of having PV clock reported as "based on a
stable TSC", because some of them don't expect the "TSC stable" bit
(added to the pvclock ABI by KVM, but never set by Xen) to be set.
- Revert a bogus, made-up nested SVM consistency check for
TLB_CONTROL.
- Advertise flush-by-ASID support for nSVM unconditionally, as KVM
always flushes on nested transitions, i.e. always satisfies flush
requests. This allows running bleeding edge versions of VMware
Workstation on top of KVM.
- Sanity check that the CPU supports flush-by-ASID when enabling SEV
support.
- On AMD machines with vNMI, always rely on hardware instead of
intercepting IRET in some cases to detect unmasking of NMIs
- Support for virtualizing Linear Address Masking (LAM)
- Fix a variety of vPMU bugs where KVM fail to stop/reset counters
and other state prior to refreshing the vPMU model.
- Fix a double-overflow PMU bug by tracking emulated counter events
using a dedicated field instead of snapshotting the "previous"
counter. If the hardware PMC count triggers overflow that is
recognized in the same VM-Exit that KVM manually bumps an event
count, KVM would pend PMIs for both the hardware-triggered overflow
and for KVM-triggered overflow.
- Turn off KVM_WERROR by default for all configs so that it's not
inadvertantly enabled by non-KVM developers, which can be
problematic for subsystems that require no regressions for W=1
builds.
- Advertise all of the host-supported CPUID bits that enumerate
IA32_SPEC_CTRL "features".
- Don't force a masterclock update when a vCPU synchronizes to the
current TSC generation, as updating the masterclock can cause
kvmclock's time to "jump" unexpectedly, e.g. when userspace
hotplugs a pre-created vCPU.
- Use RIP-relative address to read kvm_rebooting in the VM-Enter
fault paths, partly as a super minor optimization, but mostly to
make KVM play nice with position independent executable builds.
- Guard KVM-on-HyperV's range-based TLB flush hooks with an #ifdef on
CONFIG_HYPERV as a minor optimization, and to self-document the
code.
- Add CONFIG_KVM_HYPERV to allow disabling KVM support for HyperV
"emulation" at build time.
ARM64:
- LPA2 support, adding 52bit IPA/PA capability for 4kB and 16kB base
granule sizes. Branch shared with the arm64 tree.
- Large Fine-Grained Trap rework, bringing some sanity to the
feature, although there is more to come. This comes with a prefix
branch shared with the arm64 tree.
- Some additional Nested Virtualization groundwork, mostly
introducing the NV2 VNCR support and retargetting the NV support to
that version of the architecture.
- A small set of vgic fixes and associated cleanups.
Loongarch:
- Optimization for memslot hugepage checking
- Cleanup and fix some HW/SW timer issues
- Add LSX/LASX (128bit/256bit SIMD) support
RISC-V:
- KVM_GET_REG_LIST improvement for vector registers
- Generate ISA extension reg_list using macros in get-reg-list
selftest
- Support for reporting steal time along with selftest
s390:
- Bugfixes
Selftests:
- Fix an annoying goof where the NX hugepage test prints out garbage
instead of the magic token needed to run the test.
- Fix build errors when a header is delete/moved due to a missing
flag in the Makefile.
- Detect if KVM bugged/killed a selftest's VM and print out a helpful
message instead of complaining that a random ioctl() failed.
- Annotate the guest printf/assert helpers with __printf(), and fix
the various bugs that were lurking due to lack of said annotation"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (185 commits)
x86/kvm: Do not try to disable kvmclock if it was not enabled
KVM: x86: add missing "depends on KVM"
KVM: fix direction of dependency on MMU notifiers
KVM: introduce CONFIG_KVM_COMMON
KVM: arm64: Add missing memory barriers when switching to pKVM's hyp pgd
KVM: arm64: vgic-its: Avoid potential UAF in LPI translation cache
RISC-V: KVM: selftests: Add get-reg-list test for STA registers
RISC-V: KVM: selftests: Add steal_time test support
RISC-V: KVM: selftests: Add guest_sbi_probe_extension
RISC-V: KVM: selftests: Move sbi_ecall to processor.c
RISC-V: KVM: Implement SBI STA extension
RISC-V: KVM: Add support for SBI STA registers
RISC-V: KVM: Add support for SBI extension registers
RISC-V: KVM: Add SBI STA info to vcpu_arch
RISC-V: KVM: Add steal-update vcpu request
RISC-V: KVM: Add SBI STA extension skeleton
RISC-V: paravirt: Implement steal-time support
RISC-V: Add SBI STA extension definitions
RISC-V: paravirt: Add skeleton for pv-time support
RISC-V: KVM: Fix indentation in kvm_riscv_vcpu_set_reg_csr()
...
LoongArch already supports two crashkernel regions in kexec-tools, so we
can directly use the common interface to support crashkernel=X,[high,low]
after commit 0ab97169aa ("crash_core: add generic function to do
reservation").
With the help of newly changed function parse_crashkernel() and generic
reserve_crashkernel_generic(), crashkernel reservation can be simplified
by steps:
1) Add a new header file <asm/crash_core.h>, then define CRASH_ALIGN,
CRASH_ADDR_LOW_MAX and CRASH_ADDR_HIGH_MAX and in <asm/crash_core.h>;
2) Add arch_reserve_crashkernel() to call parse_crashkernel() and
reserve_crashkernel_generic();
3) Add ARCH_HAS_GENERIC_CRASHKERNEL_RESERVATION Kconfig in
arch/loongarch/Kconfig.
One can reserve the crash kernel from high memory above DMA zone range
by explicitly passing "crashkernel=X,high"; or reserve a memory range
below 4G with "crashkernel=X,low". Besides, there are few rules need to
take notice:
1) "crashkernel=X,[high,low]" will be ignored if "crashkernel=size" is
specified.
2) "crashkernel=X,low" is valid only when "crashkernel=X,high" is passed
and there is enough memory to be allocated under 4G.
3) When allocating crashkernel above 4G and no "crashkernel=X,low" is
specified, a 128M low memory will be allocated automatically for
swiotlb bounce buffer.
See Documentation/admin-guide/kernel-parameters.txt for more information.
Following test cases have been performed as expected:
1) crashkernel=256M //low=256M
2) crashkernel=1G //low=1G
3) crashkernel=4G //high=4G, low=128M(default)
4) crashkernel=4G crashkernel=256M,high //high=4G, low=128M(default), high is ignored
5) crashkernel=4G crashkernel=256M,low //high=4G, low=128M(default), low is ignored
6) crashkernel=4G,high //high=4G, low=128M(default)
7) crashkernel=256M,low //low=0M, invalid
8) crashkernel=4G,high crashkernel=256M,low //high=4G, low=256M
9) crashkernel=4G,high crashkernel=4G,low //high=0M, low=0M, invalid
10) crashkernel=512M@2560M //low=512M
11) crashkernel=1G,high crashkernel=0M,low //high=1G, low=0M
Recommended usage in general:
1) In the case of small memory: crashkernel=512M
2) In the case of large memory: crashkernel=1024M,high crashkernel=128M,low
Signed-off-by: Youling Tang <tangyouling@kylinos.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
This pull request contains the following branches:
doc.2023.12.13a: Documentation and comment updates.
torture.2023.11.23a: RCU torture, locktorture updates that include
cleanups; nolibc init build support for mips, ppc and rv64;
testing of mid stall duration scenario and fixing fqs task
creation conditions.
fixes.2023.12.13a: Misc fixes, most notably restricting usage of
RCU CPU stall notifiers, to confine their usage primarily
to debug kernels.
rcu-tasks.2023.12.12b: RCU tasks minor fixes.
srcu.2023.12.13a: lockdep annotation fix for NMI-safe accesses,
callback advancing/acceleration cleanup and documentation
improvements.
-----BEGIN PGP SIGNATURE-----
iHUEABYIAB0WIQSi2tPIQIc2VEtjarIAHS7/6Z0wpQUCZYUS0AAKCRAAHS7/6Z0w
pRXgAQD+k8oqjvKL6la61ppWm5Y7NLjdj/IbV+cOd42jKnM6PAEAyavNhX0n7zGx
o9cDlvIDxJfHnFrOTc5WLH9yEs3IiQQ=
=8rdu
-----END PGP SIGNATURE-----
Merge tag 'rcu.release.v6.8' of https://github.com/neeraju/linux
Pull RCU updates from Neeraj Upadhyay:
- Documentation and comment updates
- RCU torture, locktorture updates that include cleanups; nolibc init
build support for mips, ppc and rv64; testing of mid stall duration
scenario and fixing fqs task creation conditions
- Misc fixes, most notably restricting usage of RCU CPU stall
notifiers, to confine their usage primarily to debug kernels
- RCU tasks minor fixes
- lockdep annotation fix for NMI-safe accesses, callback
advancing/acceleration cleanup and documentation improvements
* tag 'rcu.release.v6.8' of https://github.com/neeraju/linux:
rcu: Force quiescent states only for ongoing grace period
doc: Clarify historical disclaimers in memory-barriers.txt
doc: Mention address and data dependencies in rcu_dereference.rst
doc: Clarify RCU Tasks reader/updater checklist
rculist.h: docs: Fix wrong function summary
Documentation: RCU: Remove repeated word in comments
srcu: Use try-lock lockdep annotation for NMI-safe access.
srcu: Explain why callbacks invocations can't run concurrently
srcu: No need to advance/accelerate if no callback enqueued
srcu: Remove superfluous callbacks advancing from srcu_gp_start()
rcu: Remove unused macros from rcupdate.h
rcu: Restrict access to RCU CPU stall notifiers
rcu-tasks: Mark RCU Tasks accesses to current->rcu_tasks_idle_cpu
rcutorture: Add fqs_holdoff check before fqs_task is created
rcutorture: Add mid-sized stall to TREE07
rcutorture: add nolibc init support for mips, ppc and rv64
locktorture: Increase Hamming distance between call_rcu_chain and rcu_call_chains
- The minimum Sphinx requirement has been raised to 2.4.4, following a
warning that was added in 6.2.
- Some reworking of the Documentation/process front page to, hopefully,
make it more useful.
- Various kernel-doc tweaks to, for example, make it deal properly with
__counted_by annotations.
- We have also restored a warning for documentation of nonexistent
structure members that disappeared a while back. That had the delightful
consequence of adding some 600 warnings to the docs build. A sustained
effort by Randy, Vegard, and myself has addressed almost all of those,
bringing the documentation back into sync with the code. The fixes are
going through the appropriate maintainer trees.
- Various improvements to the HTML rendered docs, including automatic links
to Git revisions and a nice new pulldown to make translations easy to
access.
- Speaking of translations, more of those for Spanish and Chinese.
...plus the usual stream of documentation updates and typo fixes.
-----BEGIN PGP SIGNATURE-----
iQFDBAABCAAtFiEEIw+MvkEiF49krdp9F0NaE2wMflgFAmWcRKMPHGNvcmJldEBs
d24ubmV0AAoJEBdDWhNsDH5YTKIH/AxBt/3iWt40dPf18arZHLU6tdUbmg01ttef
CNKWkniCmABGKc//KYDXvjZMRDt0YlrS0KgUzrb8nIQTBlZG40D+88EwjXE0HeGP
xt1Fk7OPOiJEqBZ3HEe0PDVfOiA+4yR6CmDKklCJuKg77X9atklneBwPUw/cOASk
CWj+BdbwPBiSNQv48Lp87rGusKwnH/g0MN2uS0z9MPr1DYjM1K8+ngZjGW24lZHt
qs5yhP43mlZGBF/lwNJXQp/xhnKAqJ9XwylBX9Wmaoxaz9yyzNVsADGvROMudgzi
9YB+Jdy7Z0JSrVoLIRhUuDOv7aW8vk+8qLmGJt2aTIsqehbQ6pk=
=fCtT
-----END PGP SIGNATURE-----
Merge tag 'docs-6.8' of git://git.lwn.net/linux
Pull documentation update from Jonathan Corbet:
"Another moderately busy cycle for documentation, including:
- The minimum Sphinx requirement has been raised to 2.4.4, following
a warning that was added in 6.2
- Some reworking of the Documentation/process front page to,
hopefully, make it more useful
- Various kernel-doc tweaks to, for example, make it deal properly
with __counted_by annotations
- We have also restored a warning for documentation of nonexistent
structure members that disappeared a while back. That had the
delightful consequence of adding some 600 warnings to the docs
build. A sustained effort by Randy, Vegard, and myself has
addressed almost all of those, bringing the documentation back into
sync with the code. The fixes are going through the appropriate
maintainer trees
- Various improvements to the HTML rendered docs, including automatic
links to Git revisions and a nice new pulldown to make translations
easy to access
- Speaking of translations, more of those for Spanish and Chinese
... plus the usual stream of documentation updates and typo fixes"
* tag 'docs-6.8' of git://git.lwn.net/linux: (57 commits)
MAINTAINERS: use tabs for indent of CONFIDENTIAL COMPUTING THREAT MODEL
A reworked process/index.rst
ring-buffer/Documentation: Add documentation on buffer_percent file
Translated the RISC-V architecture boot documentation.
Docs: remove mentions of fdformat from util-linux
Docs/zh_CN: Fix the meaning of DEBUG to pr_debug()
Documentation: move driver-api/dcdbas to userspace-api/
Documentation: move driver-api/isapnp to userspace-api/
Documentation/core-api : fix typo in workqueue
Documentation/trace: Fixed typos in the ftrace FLAGS section
kernel-doc: handle a void function without producing a warning
scripts/get_abi.pl: ignore some temp files
docs: kernel_abi.py: fix command injection
scripts/get_abi: fix source path leak
CREDITS, MAINTAINERS, docs/process/howto: Update man-pages' maintainer
docs: translations: add translations links when they exist
kernel-doc: Align quick help and the code
MAINTAINERS: add reviewer for Spanish translations
docs: ignore __counted_by attribute in structure definitions
scripts: kernel-doc: Clarify missing struct member description
..
Step 5/10 of the namespace unification of CPU mitigations related Kconfig options.
[ mingo: Converted a few more uses in comments/messages as well. ]
Suggested-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Breno Leitao <leitao@debian.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Ariel Miculas <amiculas@cisco.com>
Acked-by: Josh Poimboeuf <jpoimboe@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: https://lore.kernel.org/r/20231121160740.1249350-6-leitao@debian.org
The main updates for this release are around monitoring of regulators,
largely for error handling purposes. We allow the stream of regulator
events to be seen by userspace as netlink events and allow system
integrators to describe individual regulators as system critical with
information on how long the system is expected to last on error. The
system level error handling is very much about best effort problem
mitigation rather than providing something fully robust, the initial
drive was to provide a mechanism for trying to avoid initiating any new
writes to flash once we notice the power going out.
Otherwise it's very quiet, mainly several new Qualcomm devices.
- Support for marking regulators as system critical and providing
information on how long the system might last with those regulators
in a failure state, hooked into the existing critical shutdown error
handling.
- Optional support for generating netlink events for events, there are
use cases for system monitoring UIs and error handling.
- A command line option to leave unused controllable regulators
enabled, useful for debugging. We already only disable regulators we
were explicitly given permission to control.
- Support for Quacomm MP5496, PM8010 and PM8937.
-----BEGIN PGP SIGNATURE-----
iQEzBAABCgAdFiEEreZoqmdXGLWf4p/qJNaLcl1Uh9AFAmWbJAkACgkQJNaLcl1U
h9AmPwf/SXOxx0sp8xfmt1iJU30dg0L/0MNETf76dPFmCR8Oy1G9PLUqyzNQkTRf
bvDrLf9amRRhY4FDCT74VoEiGo7fcduHmjDfYbK/A8bwY1l1UDn0d7hLwgqoyydf
p07JbJzCHXAc1PhhMMdgOfdcpYs1Tah91CXOIdbe36pwgGJ8jwodJFD55uhXTsUZ
R4PcNs/M2A8rW8SaggopOEzDExdne/ZogpGwclTTWau0OIze2SuPVSsQfrOtAabY
BIxaMYKU5tSRdAJOSBNaL9NssUYzyO4q4hXs3Cms1p8XQlzZOVfMZznefdNHoVnw
VXlJyEvMREpg8ilwlz7KOyvyF7rshg==
=DADk
-----END PGP SIGNATURE-----
Merge tag 'regulator-v6.8' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator
Pull regulator updates from Mark Brown:
"The main updates for this release are around monitoring of regulators,
largely for error handling purposes. We allow the stream of regulator
events to be seen by userspace as netlink events and allow system
integrators to describe individual regulators as system critical with
information on how long the system is expected to last on error. The
system level error handling is very much about best effort problem
mitigation rather than providing something fully robust, the initial
drive was to provide a mechanism for trying to avoid initiating any
new writes to flash once we notice the power going out.
Otherwise it's very quiet, mainly several new Qualcomm devices.
- Support for marking regulators as system critical and providing
information on how long the system might last with those regulators
in a failure state, hooked into the existing critical shutdown
error handling.
- Optional support for generating netlink events for events, there
are use cases for system monitoring UIs and error handling.
- A command line option to leave unused controllable regulators
enabled, useful for debugging. We already only disable regulators
we were explicitly given permission to control.
- Support for Quacomm MP5496, PM8010 and PM8937"
* tag 'regulator-v6.8' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator: (31 commits)
regulator: event: Ensure atomicity for sequence number
uapi: regulator: Fix typo
regulator: Reuse LINEAR_RANGE() in REGULATOR_LINEAR_RANGE()
dt-bindings: regulator: qcom,usb-vbus-regulator: clean up example
regulator: qcom_smd: Add LDO5 MP5496 regulator
regulator: qcom-rpmh: add support for pm8010 regulators
regulator: dt-bindings: qcom,rpmh: add compatible for pm8010
regulator: qcom-rpmh: extend to support multiple linear voltage ranges
regulator: wm8350: Convert to platform remove callback returning void
regulator: virtual: Convert to platform remove callback returning void
regulator: userspace-consumer: Convert to platform remove callback returning void
regulator: uniphier: Convert to platform remove callback returning void
regulator: stm32-vrefbuf: Convert to platform remove callback returning void
regulator: db8500-prcmu: Convert to platform remove callback returning void
regulator: bd9571mwv: Convert to platform remove callback returning void
regulator: arizona-ldo1: Convert to platform remove callback returning void
regulator: event: Add regulator netlink event support
regulator: event: Add regulator netlink event support
regulator: stpmic1: Fix kernel-doc notation warnings
regulator: palmas: remove redundant initialization of pointer pdata
...
commit 23baf831a3 ("mm, treewide: redefine MAX_ORDER sanely") has
changed the definition of MAX_ORDER to be inclusive. This has caused
issues with code that was not yet upstream and depended on the previous
definition.
To draw attention to the altered meaning of the define, rename MAX_ORDER
to MAX_PAGE_ORDER.
Link: https://lkml.kernel.org/r/20231228144704.14033-2-kirill.shutemov@linux.intel.com
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Add the files and functions needed to support paravirt time on
RISC-V. Also include the common code needed for the first
application of pv-time, which is steal-time. In the next
patches we'll complete the functions to fully enable steal-time
support.
Acked-by: Palmer Dabbelt <palmer@rivosinc.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
Reviewed-by: Atish Patra <atishp@rivosinc.com>
Signed-off-by: Andrew Jones <ajones@ventanamicro.com>
Signed-off-by: Anup Patel <anup@brainfault.org>
The accept_memory kernel parameter was added in commit dcdfdd40fa
("mm: Add support for unaccepted memory") but not listed in the
kernel-parameters doc. Add it there.
Acked-by: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Link: https://lore.kernel.org/r/20231214-accept_memory_param-v2-1-f38cd20a0247@suse.cz
When the kernel command line option "retain_initrd" is set, we do not
free the initrd memory. However, we also don't expose it to anyone for
consumption. That leaves us in a weird situation where the only user of
this feature is ppc64 and arm64 specific kexec tooling.
To make it more generally useful, this patch adds a kobject to the
firmware object that contains the initrd context when "retain_initrd"
is set. That way, we can access the initrd any time after boot from
user space and for example hand it into kexec as --initrd parameter
if we want to reboot the same initrd. Or inspect it directly locally.
With this patch applied, there is a new /sys/firmware/initrd file when
the kernel was booted with an initrd and "retain_initrd" command line
option is set.
Signed-off-by: Alexander Graf <graf@amazon.com>
Tested-by: Bagas Sanjaya <bagasdotme@gmail.com>
Link: https://lore.kernel.org/r/20231207235654.16622-1-graf@amazon.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Although the RCU CPU stall notifiers can be useful for dumping state when
tracking down delicate forward-progress bugs where NUMA effects cause
cache lines to be delivered to a given CPU regularly, but always in a
state that prevents that CPU from making forward progress. These bugs can
be detected by the RCU CPU stall-warning mechanism, but in some cases,
the stall-warnings printk()s disrupt the forward-progress bug before
any useful state can be obtained.
Unfortunately, the notifier mechanism added by commit 5b404fdaba ("rcu:
Add RCU CPU stall notifier") can make matters worse if used at all
carelessly. For example, if the stall warning was caused by a lock not
being released, then any attempt to acquire that lock in the notifier
will hang. This will prevent not only the notifier from producing any
useful output, but it will also prevent the stall-warning message from
ever appearing.
This commit therefore hides this new RCU CPU stall notifier
mechanism under a new RCU_CPU_STALL_NOTIFIER Kconfig option that
depends on both DEBUG_KERNEL and RCU_EXPERT. In addition, the
rcupdate.rcu_cpu_stall_notifiers=1 kernel boot parameter must also
be specified. The RCU_CPU_STALL_NOTIFIER Kconfig option's help text
contains a warning and explains the dangers of careless use, recommending
lockless notifier code. In addition, a WARN() is triggered each time
that an attempt is made to register a stall-warning notifier in kernels
built with CONFIG_RCU_CPU_STALL_NOTIFIER=y.
This combination of measures will keep use of this mechanism confined to
debug kernels and away from routine deployments.
[ paulmck: Apply Dan Carpenter feedback. ]
Fixes: 5b404fdaba ("rcu: Add RCU CPU stall notifier")
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Neeraj Upadhyay (AMD) <neeraj.iitr10@gmail.com>
This patch introduces a new USB quirk,
USB_QUIRK_SHORT_SET_ADDRESS_REQ_TIMEOUT, which modifies the timeout value
for the SET_ADDRESS request. The standard timeout for USB request/command
is 5000 ms, as recommended in the USB 3.2 specification (section 9.2.6.1).
However, certain scenarios, such as connecting devices through an APTIV
hub, can lead to timeout errors when the device enumerates as full speed
initially and later switches to high speed during chirp negotiation.
In such cases, USB analyzer logs reveal that the bus suspends for
5 seconds due to incorrect chirp parsing and resumes only after two
consecutive timeout errors trigger a hub driver reset.
Packet(54) Dir(?) Full Speed J(997.100 us) Idle( 2.850 us)
_______| Time Stamp(28 . 105 910 682)
_______|_____________________________________________________________Ch0
Packet(55) Dir(?) Full Speed J(997.118 us) Idle( 2.850 us)
_______| Time Stamp(28 . 106 910 632)
_______|_____________________________________________________________Ch0
Packet(56) Dir(?) Full Speed J(399.650 us) Idle(222.582 us)
_______| Time Stamp(28 . 107 910 600)
_______|_____________________________________________________________Ch0
Packet(57) Dir Chirp J( 23.955 ms) Idle(115.169 ms)
_______| Time Stamp(28 . 108 532 832)
_______|_____________________________________________________________Ch0
Packet(58) Dir(?) Full Speed J (Suspend)( 5.347 sec) Idle( 5.366 us)
_______| Time Stamp(28 . 247 657 600)
_______|_____________________________________________________________Ch0
This 5-second delay in device enumeration is undesirable, particularly
in automotive applications where quick enumeration is crucial
(ideally within 3 seconds).
The newly introduced quirks provide the flexibility to align with a
3-second time limit, as required in specific contexts like automotive
applications.
By reducing the SET_ADDRESS request timeout to 500 ms, the
system can respond more swiftly to errors, initiate rapid recovery, and
ensure efficient device enumeration. This change is vital for scenarios
where rapid smartphone enumeration and screen projection are essential.
To use the quirk, please write "vendor_id:product_id:p" to
/sys/bus/usb/drivers/hub/module/parameter/quirks
For example,
echo "0x2c48:0x0132:p" > /sys/bus/usb/drivers/hub/module/parameters/quirks"
Signed-off-by: Hardik Gajjar <hgajjar@de.adit-jv.com>
Reviewed-by: Alan Stern <stern@rowland.harvard.edu>
Link: https://lore.kernel.org/r/20231027152029.104363-2-hgajjar@de.adit-jv.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This may be useful for debugging and develompent purposes, when there are
drivers that depend on regulators to be enabled but do not request them.
It is inspired from the clk_ignore_unused and pd_ignore_unused parameters,
that are used to keep firmware-enabled clocks and power domains on even if
these are not used by drivers.
The parameter is not expected to be used in normal cases and should not be
needed on a platform with proper driver support.
Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>
Reviewed-by: Brian Masney <bmasney@redhat.com>
Acked-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Link: https://lore.kernel.org/r/20231107190926.1185326-1-javierm@redhat.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Including:
- Core changes:
- Make default-domains mandatory for all IOMMU drivers
- Remove group refcounting
- Add generic_single_device_group() helper and consolidate
drivers
- Cleanup map/unmap ops
- Scaling improvements for the IOVA rcache depot
- Convert dart & iommufd to the new domain_alloc_paging()
- ARM-SMMU:
- Device-tree binding update:
- Add qcom,sm7150-smmu-v2 for Adreno on SM7150 SoC
- SMMUv2:
- Support for Qualcomm SDM670 (MDSS) and SM7150 SoCs
- SMMUv3:
- Large refactoring of the context descriptor code to
move the CD table into the master, paving the way
for '->set_dev_pasid()' support on non-SVA domains
- Minor cleanups to the SVA code
- Intel VT-d:
- Enable debugfs to dump domain attached to a pasid
- Remove an unnecessary inline function.
- AMD IOMMU:
- Initial patches for SVA support (not complete yet)
- S390 IOMMU:
- DMA-API conversion and optimized IOTLB flushing
- Some smaller fixes and improvements
-----BEGIN PGP SIGNATURE-----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=UyWC
-----END PGP SIGNATURE-----
Merge tag 'iommu-updates-v6.7' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu
Pull iommu updates from Joerg Roedel:
"Core changes:
- Make default-domains mandatory for all IOMMU drivers
- Remove group refcounting
- Add generic_single_device_group() helper and consolidate drivers
- Cleanup map/unmap ops
- Scaling improvements for the IOVA rcache depot
- Convert dart & iommufd to the new domain_alloc_paging()
ARM-SMMU:
- Device-tree binding update:
- Add qcom,sm7150-smmu-v2 for Adreno on SM7150 SoC
- SMMUv2:
- Support for Qualcomm SDM670 (MDSS) and SM7150 SoCs
- SMMUv3:
- Large refactoring of the context descriptor code to move the CD
table into the master, paving the way for '->set_dev_pasid()'
support on non-SVA domains
- Minor cleanups to the SVA code
Intel VT-d:
- Enable debugfs to dump domain attached to a pasid
- Remove an unnecessary inline function
AMD IOMMU:
- Initial patches for SVA support (not complete yet)
S390 IOMMU:
- DMA-API conversion and optimized IOTLB flushing
And some smaller fixes and improvements"
* tag 'iommu-updates-v6.7' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu: (102 commits)
iommu/dart: Remove the force_bypass variable
iommu/dart: Call apple_dart_finalize_domain() as part of alloc_paging()
iommu/dart: Convert to domain_alloc_paging()
iommu/dart: Move the blocked domain support to a global static
iommu/dart: Use static global identity domains
iommufd: Convert to alloc_domain_paging()
iommu/vt-d: Use ops->blocked_domain
iommu/vt-d: Update the definition of the blocking domain
iommu: Move IOMMU_DOMAIN_BLOCKED global statics to ops->blocked_domain
Revert "iommu/vt-d: Remove unused function"
iommu/amd: Remove DMA_FQ type from domain allocation path
iommu: change iommu_map_sgtable to return signed values
iommu/virtio: Add __counted_by for struct viommu_request and use struct_size()
iommu/vt-d: debugfs: Support dumping a specified page table
iommu/vt-d: debugfs: Create/remove debugfs file per {device, pasid}
iommu/vt-d: debugfs: Dump entry pointing to huge page
iommu/vt-d: Remove unused function
iommu/arm-smmu-v3-sva: Remove bond refcount
iommu/arm-smmu-v3-sva: Remove unused iommu_sva handle
iommu/arm-smmu-v3: Rename cdcfg to cd_table
...
Highlights include:
Bugfixes:
- SUNRPC: A fix to re-probe the target RPC port after an ECONNRESET error
- SUNRPC: Handle allocation errors from rpcb_call_async()
- SUNRPC: Fix a use-after-free condition in rpc_pipefs
- SUNRPC: fix up various checks for timeouts
- NFSv4.1: Handle NFS4ERR_DELAY errors during session trunking
- NFSv4.1: fix SP4_MACH_CRED protection for pnfs IO
- NFSv4: Ensure that we test all delegations when the server notifies
us that it may have revoked some of them
Features:
- Allow knfsd processes to break out of NFS4ERR_DELAY loops when
re-exporting NFSv4.x by setting appropriate values for the
'delay_retrans' module parameter.
- nfs: Convert nfs_symlink() to use a folio
-----BEGIN PGP SIGNATURE-----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=TNRl
-----END PGP SIGNATURE-----
Merge tag 'nfs-for-6.7-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs
Pull NFS client updates from Trond Myklebust:
"Bugfixes:
- SUNRPC:
- re-probe the target RPC port after an ECONNRESET error
- handle allocation errors from rpcb_call_async()
- fix a use-after-free condition in rpc_pipefs
- fix up various checks for timeouts
- NFSv4.1:
- Handle NFS4ERR_DELAY errors during session trunking
- fix SP4_MACH_CRED protection for pnfs IO
- NFSv4:
- Ensure that we test all delegations when the server notifies
us that it may have revoked some of them
Features:
- Allow knfsd processes to break out of NFS4ERR_DELAY loops when
re-exporting NFSv4.x by setting appropriate values for the
'delay_retrans' module parameter
- nfs: Convert nfs_symlink() to use a folio"
* tag 'nfs-for-6.7-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs:
nfs: Convert nfs_symlink() to use a folio
SUNRPC: Fix RPC client cleaned up the freed pipefs dentries
NFSv4.1: fix SP4_MACH_CRED protection for pnfs IO
SUNRPC: Add an IS_ERR() check back to where it was
NFSv4.1: fix handling NFS4ERR_DELAY when testing for session trunking
nfs41: drop dependency between flexfiles layout driver and NFSv3 modules
NFSv4: fairly test all delegations on a SEQ4_ revocation
SUNRPC: SOFTCONN tasks should time out when on the sending list
SUNRPC: Force close the socket when a hard error is reported
SUNRPC: Don't skip timeout checks in call_connect_status()
SUNRPC: ECONNRESET might require a rebind
NFSv4/pnfs: Allow layoutget to return EAGAIN for softerr mounts
NFSv4: Add a parameter to limit the number of retries after NFS4ERR_DELAY
Gleixner:
- Restructure the code needed for it and add a temporary initrd mapping
on 32-bit so that the loader can access the microcode blobs. This in
itself is a preparation for the next major improvement:
- Do not load microcode on 32-bit before paging has been enabled.
Handling this has caused an endless stream of headaches, issues, ugly
code and unnecessary hacks in the past. And there really wasn't any
sensible reason to do that in the first place. So switch the 32-bit
loading to happen after paging has been enabled and turn the loader
code "real purrty" again
- Drop mixed microcode steppings loading on Intel - there, a single patch
loaded on the whole system is sufficient
- Rework late loading to track which CPUs have updated microcode
successfully and which haven't, act accordingly
- Move late microcode loading on Intel in NMI context in order to
guarantee concurrent loading on all threads
- Make the late loading CPU-hotplug-safe and have the offlined threads
be woken up for the purpose of the update
- Add support for a minimum revision which determines whether late
microcode loading is safe on a machine and the microcode does not
change software visible features which the machine cannot use anyway
since feature detection has happened already. Roughly, the minimum
revision is the smallest revision number which must be loaded
currently on the system so that late updates can be allowed
- Other nice leanups, fixess, etc all over the place
-----BEGIN PGP SIGNATURE-----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=JOZu
-----END PGP SIGNATURE-----
Merge tag 'x86_microcode_for_v6.7_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 microcode loading updates from Borislac Petkov:
"Major microcode loader restructuring, cleanup and improvements by
Thomas Gleixner:
- Restructure the code needed for it and add a temporary initrd
mapping on 32-bit so that the loader can access the microcode
blobs. This in itself is a preparation for the next major
improvement:
- Do not load microcode on 32-bit before paging has been enabled.
Handling this has caused an endless stream of headaches, issues,
ugly code and unnecessary hacks in the past. And there really
wasn't any sensible reason to do that in the first place. So switch
the 32-bit loading to happen after paging has been enabled and turn
the loader code "real purrty" again
- Drop mixed microcode steppings loading on Intel - there, a single
patch loaded on the whole system is sufficient
- Rework late loading to track which CPUs have updated microcode
successfully and which haven't, act accordingly
- Move late microcode loading on Intel in NMI context in order to
guarantee concurrent loading on all threads
- Make the late loading CPU-hotplug-safe and have the offlined
threads be woken up for the purpose of the update
- Add support for a minimum revision which determines whether late
microcode loading is safe on a machine and the microcode does not
change software visible features which the machine cannot use
anyway since feature detection has happened already. Roughly, the
minimum revision is the smallest revision number which must be
loaded currently on the system so that late updates can be allowed
- Other nice leanups, fixess, etc all over the place"
* tag 'x86_microcode_for_v6.7_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (40 commits)
x86/microcode/intel: Add a minimum required revision for late loading
x86/microcode: Prepare for minimal revision check
x86/microcode: Handle "offline" CPUs correctly
x86/apic: Provide apic_force_nmi_on_cpu()
x86/microcode: Protect against instrumentation
x86/microcode: Rendezvous and load in NMI
x86/microcode: Replace the all-in-one rendevous handler
x86/microcode: Provide new control functions
x86/microcode: Add per CPU control field
x86/microcode: Add per CPU result state
x86/microcode: Sanitize __wait_for_cpus()
x86/microcode: Clarify the late load logic
x86/microcode: Handle "nosmt" correctly
x86/microcode: Clean up mc_cpu_down_prep()
x86/microcode: Get rid of the schedule work indirection
x86/microcode: Mop up early loading leftovers
x86/microcode/amd: Use cached microcode for AP load
x86/microcode/amd: Cache builtin/initrd microcode early
x86/microcode/amd: Cache builtin microcode too
x86/microcode/amd: Use correct per CPU ucode_cpu_info
...
- locking/atomic: sh: Use generic_cmpxchg_local for arch_cmpxchg_local()
- Documentation: kernel-parameters: Add earlyprintk=bios on SH
- sh: bios: Revive earlyprintk support
- sh: machvec: Remove custom ioport_{un,}map()
- sh: Remove superhyway bus support
- sh: Remove unused SH4-202 support
- sh: Remove stale microdev board
-----BEGIN PGP SIGNATURE-----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=KwXl
-----END PGP SIGNATURE-----
Merge tag 'sh-for-v6.7-tag1' of git://git.kernel.org/pub/scm/linux/kernel/git/glaubitz/sh-linux
Pull sh updates from John Paul Adrian Glaubitz:
"While the previously announced patch series for converting arch/sh to
device trees is not yet ready for inclusion to mainline and therefore
didn't make it for this pull request, there are still a small number
changes for v6.7 which include one platform (board plus CPU and driver
code) removal plus two fixes.
The removal sent in by Arnd Bergmann concerns the microdev board which
was an early SuperH prototype board that was never used in production.
With the board removed, we were able to drop the now unused code for
the SH4-202 CPU and well as the driver code for the superhyway bus and
a custom implementation for ioport_map() and ioport_unmap() which will
allow us to simplify ioport handling in the future.
Another patch set by Geert Uytterhoeven revives SuperH BIOS
earlyprintk support which got accidentally disabled in
e76fe57447 ("sh: Remove old early serial console code V2"), the
second patch in the series updates the documentation.
Finally, a patch by Masami Hiramatsu fixes a regression reported by
the kernel test robot which uncovered that arch/sh is not implementing
arch_cmpxchg_local() and therefore needs use __generic_cmpxchg_local()
instead"
* tag 'sh-for-v6.7-tag1' of git://git.kernel.org/pub/scm/linux/kernel/git/glaubitz/sh-linux:
locking/atomic: sh: Use generic_cmpxchg_local for arch_cmpxchg_local()
Documentation: kernel-parameters: Add earlyprintk=bios on SH
sh: bios: Revive earlyprintk support
sh: machvec: Remove custom ioport_{un,}map()
sh: Remove superhyway bus support
sh: Remove unused SH4-202 support
sh: Remove stale microdev board
The ia64 architecture gets its well-earned retirement as planned,
now that there is one last (mostly) working release that will
be maintained as an LTS kernel.
The architecture specific system call tables are updated for
the added map_shadow_stack() syscall and to remove references
to the long-gone sys_lookup_dcookie() syscall.
-----BEGIN PGP SIGNATURE-----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=H1vH
-----END PGP SIGNATURE-----
Merge tag 'asm-generic-6.7' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic
Pull ia64 removal and asm-generic updates from Arnd Bergmann:
- The ia64 architecture gets its well-earned retirement as planned,
now that there is one last (mostly) working release that will be
maintained as an LTS kernel.
- The architecture specific system call tables are updated for the
added map_shadow_stack() syscall and to remove references to the
long-gone sys_lookup_dcookie() syscall.
* tag 'asm-generic-6.7' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic:
hexagon: Remove unusable symbols from the ptrace.h uapi
asm-generic: Fix spelling of architecture
arch: Reserve map_shadow_stack() syscall number for all architectures
syscalls: Cleanup references to sys_lookup_dcookie()
Documentation: Drop or replace remaining mentions of IA64
lib/raid6: Drop IA64 support
Documentation: Drop IA64 from feature descriptions
kernel: Drop IA64 support from sig_fault handlers
arch: Remove Itanium (IA-64) architecture
* cpuset now supports remote partitions where CPUs can be reserved for
exclusive use down the tree without requiring all the intermediate nodes
to be partitions. This makes it easier to use partitions without modifying
existing cgroup hierarchy.
* cpuset partition configuration behavior improvement.
* cgroup_favordynmods= boot param added to allow setting the flag on boot on
cgroup1.
* Misc code and doc updates.
-----BEGIN PGP SIGNATURE-----
iIQEABYIACwWIQTfIjM1kS57o3GsC/uxYfJx3gVYGQUCZUBUKA4cdGpAa2VybmVs
Lm9yZwAKCRCxYfJx3gVYGWfMAP9WP+Z21qzzL2bY5I5kOxu+rD2fF9ORk7azILrI
c3gXSQD/bdxNWcdtrCQMvs+ToNEJvqDFxrmgG5uRUF8Ea+FCtQ8=
=gZj2
-----END PGP SIGNATURE-----
Merge tag 'cgroup-for-6.7' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup
Pull cgroup updates from Tejun Heo:
- cpuset now supports remote partitions where CPUs can be reserved for
exclusive use down the tree without requiring all the intermediate
nodes to be partitions. This makes it easier to use partitions
without modifying existing cgroup hierarchy.
- cpuset partition configuration behavior improvement
- cgroup_favordynmods= boot param added to allow setting the flag on
boot on cgroup1
- Misc code and doc updates
* tag 'cgroup-for-6.7' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
docs/cgroup: Add the list of threaded controllers to cgroup-v2.rst
cgroup: use legacy_name for cgroup v1 disable info
cgroup/cpuset: Cleanup signedness issue in cpu_exclusive_check()
cgroup/cpuset: Enable invalid to valid local partition transition
cgroup: add cgroup_favordynmods= command-line option
cgroup/cpuset: Extend test_cpuset_prs.sh to test remote partition
cgroup/cpuset: Documentation update for partition
cgroup/cpuset: Check partition conflict with housekeeping setup
cgroup/cpuset: Introduce remote partition
cgroup/cpuset: Add cpuset.cpus.exclusive for v2
cgroup/cpuset: Add cpuset.cpus.exclusive.effective for v2
cgroup/cpuset: Fix load balance state in update_partition_sd_lb()
cgroup: Avoid extra dereference in css_populate_dir()
cgroup: Check for ret during cgroup1_base_files cft addition
This pull request contains the following branches:
rcu/torture: RCU torture, locktorture and generic torture infrastructure
updates that include various fixes, cleanups and consolidations.
Among the user visible things, ftrace dumps can now be found into
their own file, and module parameters get better documented and
reported on dumps.
rcu/fixes: Generic and misc fixes all over the place. Some highlights:
* Hotplug handling has seen some light cleanups and comments.
* An RCU barrier can now be triggered through sysfs to serialize
memory stress testing and avoid OOM.
* Object information is now dumped in case of invalid callback
invocation.
* Also various SRCU issues, too hard to trigger to deserve urgent
pull requests, have been fixed.
rcu/docs: RCU documentation updates
rcu/refscale: RCU reference scalability test minor fixes and doc
improvements.
rcu/tasks: RCU tasks minor fixes
rcu/stall: Stall detection updates. Introduce RCU CPU Stall notifiers
that allows a subsystem to provide informations to help debugging.
Also cure some false positive stalls.
-----BEGIN PGP SIGNATURE-----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=cVD7
-----END PGP SIGNATURE-----
Merge tag 'rcu-next-v6.7' of git://git.kernel.org/pub/scm/linux/kernel/git/frederic/linux-dynticks
Pull RCU updates from Frederic Weisbecker:
- RCU torture, locktorture and generic torture infrastructure updates
that include various fixes, cleanups and consolidations.
Among the user visible things, ftrace dumps can now be found into
their own file, and module parameters get better documented and
reported on dumps.
- Generic and misc fixes all over the place. Some highlights:
* Hotplug handling has seen some light cleanups and comments
* An RCU barrier can now be triggered through sysfs to serialize
memory stress testing and avoid OOM
* Object information is now dumped in case of invalid callback
invocation
* Also various SRCU issues, too hard to trigger to deserve urgent
pull requests, have been fixed
- RCU documentation updates
- RCU reference scalability test minor fixes and doc improvements.
- RCU tasks minor fixes
- Stall detection updates. Introduce RCU CPU Stall notifiers that
allows a subsystem to provide informations to help debugging. Also
cure some false positive stalls.
* tag 'rcu-next-v6.7' of git://git.kernel.org/pub/scm/linux/kernel/git/frederic/linux-dynticks: (56 commits)
srcu: Only accelerate on enqueue time
locktorture: Check the correct variable for allocation failure
srcu: Fix callbacks acceleration mishandling
rcu: Comment why callbacks migration can't wait for CPUHP_RCUTREE_PREP
rcu: Standardize explicit CPU-hotplug calls
rcu: Conditionally build CPU-hotplug teardown callbacks
rcu: Remove references to rcu_migrate_callbacks() from diagrams
rcu: Assume rcu_report_dead() is always called locally
rcu: Assume IRQS disabled from rcu_report_dead()
rcu: Use rcu_segcblist_segempty() instead of open coding it
rcu: kmemleak: Ignore kmemleak false positives when RCU-freeing objects
srcu: Fix srcu_struct node grpmask overflow on 64-bit systems
torture: Convert parse-console.sh to mktemp
rcutorture: Traverse possible cpu to set maxcpu in rcu_nocb_toggle()
rcutorture: Replace schedule_timeout*() 1-jiffy waits with HZ/20
torture: Add kvm.sh --debug-info argument
locktorture: Rename readers_bind/writers_bind to bind_readers/bind_writers
doc: Catch-up update for locktorture module parameters
locktorture: Add call_rcu_chains module parameter
locktorture: Add new module parameters to lock_torture_print_module_parms()
...
This series adds a kernel boot parameter that causes the kernel to
panic if one of the call_smp_function() APIs is stalled for more than
the specified duration. This is useful in deployments in which a clean
panic is preferable to an indefinite stall.
-----BEGIN PGP SIGNATURE-----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=ZD0S
-----END PGP SIGNATURE-----
Merge tag 'csd-lock.2023.10.23a' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu
Pull CSD lock update from Paul McKenney:
"This adds a kernel boot parameter that causes the kernel to panic if
one of the call_smp_function() APIs is stalled for more than the
specified duration.
This is useful in deployments in which a clean panic is preferable to
an indefinite stall"
* tag 'csd-lock.2023.10.23a' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu:
smp,csd: Throw an error if a CSD lock is stuck for too long
Document the use of the "earlyprintk=bios[,keep]" kernel parameter
option on SuperH systems with a SuperH standard BIOS.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Link: https://lore.kernel.org/r/febc920964f2f0919d21775132e84c5cc270177e.1697708489.git.geert+renesas@glider.be
Signed-off-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Applying microcode late can be fatal for the running kernel when the
update changes functionality which is in use already in a non-compatible
way, e.g. by removing a CPUID bit.
There is no way for admins which do not have access to the vendors deep
technical support to decide whether late loading of such a microcode is
safe or not.
Intel has added a new field to the microcode header which tells the
minimal microcode revision which is required to be active in the CPU in
order to be safe.
Provide infrastructure for handling this in the core code and a command
line switch which allows to enforce it.
If the update is considered safe the kernel is not tainted and the annoying
warning message not emitted. If it's enforced and the currently loaded
microcode revision is not safe for late loading then the load is aborted.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/r/20231017211724.079611170@linutronix.de
When using a 'softerr' mount, the NFSv4 client can get stuck waiting
forever while the server just returns NFS4ERR_DELAY. Among other things,
this causes the knfsd server threads to busy wait.
Add a parameter that tells the NFSv4 client how many times to retry
before giving up.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
The CSD lock seems to get stuck in 2 "modes". When it gets stuck
temporarily, it usually gets released in a few seconds, and sometimes
up to one or two minutes.
If the CSD lock stays stuck for more than several minutes, it never
seems to get unstuck, and gradually more and more things in the system
end up also getting stuck.
In the latter case, we should just give up, so the system can dump out
a little more information about what went wrong, and, with panic_on_oops
and a kdump kernel loaded, dump a whole bunch more information about what
might have gone wrong. In addition, there is an smp.panic_on_ipistall
kernel boot parameter that by default retains the old behavior, but when
set enables the panic after the CSD lock has been stuck for more than
the specified number of milliseconds, as in 300,000 for five minutes.
[ paulmck: Apply Imran Khan feedback. ]
[ paulmck: Apply Leonardo Bras feedback. ]
Link: https://lore.kernel.org/lkml/bc7cc8b0-f587-4451-8bcd-0daae627bcc7@paulmck-laptop/
Signed-off-by: Rik van Riel <riel@surriel.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Reviewed-by: Imran Khan <imran.f.khan@oracle.com>
Reviewed-by: Leonardo Bras <leobras@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Valentin Schneider <vschneid@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Randy Dunlap <rdunlap@infradead.org>
Linus Torvalds