Commit graph

105 commits

Author SHA1 Message Date
Dongxu Sun
19e99e7d59 arm64/signal: Alloc tpidr2 sigframe after checking system_supports_tpidr2()
Move tpidr2 sigframe allocation from under the checking of
system_supports_sme() to the checking of system_supports_tpidr2().

Signed-off-by: Dongxu Sun <sundongxu3@huawei.com>
Reviewed-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20230317124915.1263-3-sundongxu3@huawei.com
Signed-off-by: Will Deacon <will@kernel.org>
2023-04-12 09:41:48 +01:00
Dongxu Sun
e9d14f3f3f arm64/signal: Use system_supports_tpidr2() to check TPIDR2
Since commit a9d6915859501("arm64/sme: Implement support
for TPIDR2"), We introduced system_supports_tpidr2() for
TPIDR2 handling. Let's use the specific check instead.

No functional changes.

Signed-off-by: Dongxu Sun <sundongxu3@huawei.com>
Reviewed-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20230317124915.1263-2-sundongxu3@huawei.com
Signed-off-by: Will Deacon <will@kernel.org>
2023-04-12 09:41:48 +01:00
Linus Torvalds
8bf1a529cd arm64 updates for 6.3:
- Support for arm64 SME 2 and 2.1. SME2 introduces a new 512-bit
   architectural register (ZT0, for the look-up table feature) that Linux
   needs to save/restore.
 
 - Include TPIDR2 in the signal context and add the corresponding
   kselftests.
 
 - Perf updates: Arm SPEv1.2 support, HiSilicon uncore PMU updates, ACPI
   support to the Marvell DDR and TAD PMU drivers, reset DTM_PMU_CONFIG
   (ARM CMN) at probe time.
 
 - Support for DYNAMIC_FTRACE_WITH_CALL_OPS on arm64.
 
 - Permit EFI boot with MMU and caches on. Instead of cleaning the entire
   loaded kernel image to the PoC and disabling the MMU and caches before
   branching to the kernel bare metal entry point, leave the MMU and
   caches enabled and rely on EFI's cacheable 1:1 mapping of all of
   system RAM to populate the initial page tables.
 
 - Expose the AArch32 (compat) ELF_HWCAP features to user in an arm64
   kernel (the arm32 kernel only defines the values).
 
 - Harden the arm64 shadow call stack pointer handling: stash the shadow
   stack pointer in the task struct on interrupt, load it directly from
   this structure.
 
 - Signal handling cleanups to remove redundant validation of size
   information and avoid reading the same data from userspace twice.
 
 - Refactor the hwcap macros to make use of the automatically generated
   ID registers. It should make new hwcaps writing less error prone.
 
 - Further arm64 sysreg conversion and some fixes.
 
 - arm64 kselftest fixes and improvements.
 
 - Pointer authentication cleanups: don't sign leaf functions, unify
   asm-arch manipulation.
 
 - Pseudo-NMI code generation optimisations.
 
 - Minor fixes for SME and TPIDR2 handling.
 
 - Miscellaneous updates: ARCH_FORCE_MAX_ORDER is now selectable, replace
   strtobool() to kstrtobool() in the cpufeature.c code, apply dynamic
   shadow call stack in two passes, intercept pfn changes in set_pte_at()
   without the required break-before-make sequence, attempt to dump all
   instructions on unhandled kernel faults.
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Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux

Pull arm64 updates from Catalin Marinas:

 - Support for arm64 SME 2 and 2.1. SME2 introduces a new 512-bit
   architectural register (ZT0, for the look-up table feature) that
   Linux needs to save/restore

 - Include TPIDR2 in the signal context and add the corresponding
   kselftests

 - Perf updates: Arm SPEv1.2 support, HiSilicon uncore PMU updates, ACPI
   support to the Marvell DDR and TAD PMU drivers, reset DTM_PMU_CONFIG
   (ARM CMN) at probe time

 - Support for DYNAMIC_FTRACE_WITH_CALL_OPS on arm64

 - Permit EFI boot with MMU and caches on. Instead of cleaning the
   entire loaded kernel image to the PoC and disabling the MMU and
   caches before branching to the kernel bare metal entry point, leave
   the MMU and caches enabled and rely on EFI's cacheable 1:1 mapping of
   all of system RAM to populate the initial page tables

 - Expose the AArch32 (compat) ELF_HWCAP features to user in an arm64
   kernel (the arm32 kernel only defines the values)

 - Harden the arm64 shadow call stack pointer handling: stash the shadow
   stack pointer in the task struct on interrupt, load it directly from
   this structure

 - Signal handling cleanups to remove redundant validation of size
   information and avoid reading the same data from userspace twice

 - Refactor the hwcap macros to make use of the automatically generated
   ID registers. It should make new hwcaps writing less error prone

 - Further arm64 sysreg conversion and some fixes

 - arm64 kselftest fixes and improvements

 - Pointer authentication cleanups: don't sign leaf functions, unify
   asm-arch manipulation

 - Pseudo-NMI code generation optimisations

 - Minor fixes for SME and TPIDR2 handling

 - Miscellaneous updates: ARCH_FORCE_MAX_ORDER is now selectable,
   replace strtobool() to kstrtobool() in the cpufeature.c code, apply
   dynamic shadow call stack in two passes, intercept pfn changes in
   set_pte_at() without the required break-before-make sequence, attempt
   to dump all instructions on unhandled kernel faults

* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (130 commits)
  arm64: fix .idmap.text assertion for large kernels
  kselftest/arm64: Don't require FA64 for streaming SVE+ZA tests
  kselftest/arm64: Copy whole EXTRA context
  arm64: kprobes: Drop ID map text from kprobes blacklist
  perf: arm_spe: Print the version of SPE detected
  perf: arm_spe: Add support for SPEv1.2 inverted event filtering
  perf: Add perf_event_attr::config3
  arm64/sme: Fix __finalise_el2 SMEver check
  drivers/perf: fsl_imx8_ddr_perf: Remove set-but-not-used variable
  arm64/signal: Only read new data when parsing the ZT context
  arm64/signal: Only read new data when parsing the ZA context
  arm64/signal: Only read new data when parsing the SVE context
  arm64/signal: Avoid rereading context frame sizes
  arm64/signal: Make interface for restore_fpsimd_context() consistent
  arm64/signal: Remove redundant size validation from parse_user_sigframe()
  arm64/signal: Don't redundantly verify FPSIMD magic
  arm64/cpufeature: Use helper macros to specify hwcaps
  arm64/cpufeature: Always use symbolic name for feature value in hwcaps
  arm64/sysreg: Initial unsigned annotations for ID registers
  arm64/sysreg: Initial annotation of signed ID registers
  ...
2023-02-21 15:27:48 -08:00
Mark Brown
ad678be423 arm64/signal: Only read new data when parsing the ZT context
When we parse the ZT signal context we read the entire context from
userspace, including the generic signal context header which was already
read by parse_user_sigframe() and padding bytes that we ignore. Avoid the
possibility of relying on the second read of the data read twice by only
reading the data which we are actually going to use.

Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20221212-arm64-signal-cleanup-v3-7-4545c94b20ff@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2023-02-01 17:56:47 +00:00
Mark Brown
24d68345a0 arm64/signal: Only read new data when parsing the ZA context
When we parse the ZA signal context we read the entire context from
userspace, including the generic signal context header which was already
read by parse_user_sigframe() and padding bytes that we ignore. Avoid the
possibility of relying on the second read of the data read twice by only
reading the data which we are actually going to use.

Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20221212-arm64-signal-cleanup-v3-6-4545c94b20ff@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2023-02-01 17:56:47 +00:00
Mark Brown
f3ac48aa3a arm64/signal: Only read new data when parsing the SVE context
When we parse the SVE signal context we read the entire context from
userspace, including the generic signal context header which was already
read by parse_user_sigframe() and padding bytes that we ignore. Avoid the
possibility of relying on the second read of the data read twice by only
reading the data which we are actually going to use.

Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20221212-arm64-signal-cleanup-v3-5-4545c94b20ff@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2023-02-01 17:56:47 +00:00
Mark Brown
b57682b315 arm64/signal: Avoid rereading context frame sizes
We need to read the sizes of the signal context frames as part of parsing
the overall signal context in parse_user_sigframe(). In the cases where we
defer frame specific parsing to other functions those functions (other
than the recently added TPIDR2 parser) reread the size and validate the
version they read, opening the possibility that the value may change.
Avoid this possibility by passing the size read in parse_user_sigframe()
through user_ctxs and referring to that.

For consistency we move the size check for the TPIDR2 context into the
TPIDR2 parsing function.

Note that for SVE, ZA and ZT contexts we still read the size again but
after this change we no longer use the value, further changes will avoid
the read.

Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20221212-arm64-signal-cleanup-v3-4-4545c94b20ff@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2023-02-01 17:56:47 +00:00
Mark Brown
4e4e93045f arm64/signal: Make interface for restore_fpsimd_context() consistent
Instead of taking a pointer to struct user_ctxs like the other two
restore_blah_context() functions the FPSIMD function takes a pointer to the
user struct it should read. Change it to be consistent with the rest, both
for consistency and to prepare for changes which avoid rereading data that
has already been read by the core parsing code.

There should be no functional change from this patch.

Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20221212-arm64-signal-cleanup-v3-3-4545c94b20ff@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2023-02-01 17:56:47 +00:00
Mark Brown
0eb23720f2 arm64/signal: Remove redundant size validation from parse_user_sigframe()
There is some minimal size validation in parse_user_sigframe() however
all of the individual parsing functions perform frame specific validation
of the sizing information, remove the frame specific size checks in the
core so that there isn't any confusion about what we validate for size.

Since the checks in the SVE and ZA parsing are after we have read the
relevant context and since they won't report an error if the frame is
undersized they are adjusted to check for this before doing anything else.

Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20221212-arm64-signal-cleanup-v3-2-4545c94b20ff@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2023-02-01 17:56:47 +00:00
Mark Brown
92f14518cc arm64/signal: Don't redundantly verify FPSIMD magic
We validate that the magic in the struct fpsimd_context is correct in
restore_fpsimd_context() but this is redundant since parse_user_sigframe()
uses this magic to decide to call the function in the first place. Remove
the extra validation.

Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20221212-arm64-signal-cleanup-v3-1-4545c94b20ff@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2023-02-01 17:56:47 +00:00
Catalin Marinas
ea776e4932 Merge branches 'for-next/tpidr2' and 'for-next/sme2' into for-next/signal
Patches on this branch depend on the branches merged above.
2023-02-01 17:55:29 +00:00
Mark Brown
39e5449928 arm64/signal: Include TPIDR2 in the signal context
Add a new signal frame record for TPIDR2 using the same format as we
already use for ESR with different magic, a header with the value from the
register appended as the only data. If SME is supported then this record is
always included.

Signed-off-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Szabolcs Nagy <szabolcs.nagy@arm.com>
Link: https://lore.kernel.org/r/20221208-arm64-tpidr2-sig-v3-2-c77c6c8775f4@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2023-01-20 12:42:31 +00:00
Mark Brown
ee072cf708 arm64/sme: Implement signal handling for ZT
Add a new signal context type for ZT which is present in the signal frame
when ZA is enabled and ZT is supported by the system. In order to account
for the possible addition of further ZT registers in the future we make the
number of registers variable in the ABI, though currently the only possible
number is 1. We could just use a bare list head for the context since the
number of registers can be inferred from the size of the context but for
usability and future extensibility we define a header with the number of
registers and some reserved fields in it.

Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20221208-arm64-sme2-v4-11-f2fa0aef982f@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2023-01-20 12:23:06 +00:00
Mark Brown
ce514000da arm64/sme: Rename za_state to sme_state
In preparation for adding support for storage for ZT0 to the thread_struct
rename za_state to sme_state. Since ZT0 is accessible when PSTATE.ZA is
set just like ZA itself we will extend the allocation done for ZA to
cover it, avoiding the need to further expand task_struct for non-SME
tasks.

No functional changes.

Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20221208-arm64-sme2-v4-1-f2fa0aef982f@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2023-01-20 12:23:05 +00:00
Mark Brown
f26cd73721 arm64/signal: Always allocate SVE signal frames on SME only systems
Currently we only allocate space for SVE signal frames on systems that
support SVE, meaning that SME only systems do not allocate a signal frame
for streaming mode SVE state. Change the check so space is allocated if
either feature is supported.

Fixes: 85ed24dad2 ("arm64/sme: Implement streaming SVE signal handling")
Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20221223-arm64-fix-sme-only-v1-3-938d663f69e5@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
2023-01-05 15:31:18 +00:00
Mark Brown
7dde62f068 arm64/signal: Always accept SVE signal frames on SME only systems
Currently we reject an attempt to restore a SVE signal frame on a system
with SME but not SVE supported. This means that it is not possible to
disable streaming mode via signal return as this is configured via the
flags in the SVE signal context. Instead accept the signal frame, we will
require it to have a vector length of 0 specified and no payload since the
task will have no SVE vector length configured.

Fixes: 85ed24dad2 ("arm64/sme: Implement streaming SVE signal handling")
Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20221223-arm64-fix-sme-only-v1-2-938d663f69e5@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
2023-01-05 15:31:18 +00:00
Mark Brown
baa8515281 arm64/fpsimd: Track the saved FPSIMD state type separately to TIF_SVE
When we save the state for the floating point registers this can be done
in the form visible through either the FPSIMD V registers or the SVE Z and
P registers. At present we track which format is currently used based on
TIF_SVE and the SME streaming mode state but particularly in the SVE case
this limits our options for optimising things, especially around syscalls.
Introduce a new enum which we place together with saved floating point
state in both thread_struct and the KVM guest state which explicitly
states which format is active and keep it up to date when we change it.

At present we do not use this state except to verify that it has the
expected value when loading the state, future patches will introduce
functional changes.

Signed-off-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20221115094640.112848-3-broonie@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
2022-11-29 15:01:56 +00:00
Mark Brown
826a4fdd2a arm64/sme: Don't flush SVE register state when allocating SME storage
Currently when taking a SME access trap we allocate storage for the SVE
register state in order to be able to handle storage of streaming mode SVE.
Due to the original usage in a purely SVE context the SVE register state
allocation this also flushes the register state for SVE if storage was
already allocated but in the SME context this is not desirable. For a SME
access trap to be taken the task must not be in streaming mode so either
there already is SVE register state present for regular SVE mode which would
be corrupted or the task does not have TIF_SVE and the flush is redundant.

Fix this by adding a flag to sve_alloc() indicating if we are in a SVE
context and need to flush the state. Freshly allocated storage is always
zeroed either way.

Fixes: 8bd7f91c03 ("arm64/sme: Implement traps and syscall handling for SME")
Signed-off-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Link: https://lore.kernel.org/r/20220817182324.638214-4-broonie@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
2022-08-23 11:29:11 +01:00
Mark Brown
ea64baacbc arm64/signal: Flush FPSIMD register state when disabling streaming mode
When handling a signal delivered to a context with streaming mode enabled
we will disable streaming mode for the signal handler, when doing so we
should also flush the saved FPSIMD register state like exiting streaming
mode in the hardware would do so that if that state is reloaded we get the
same behaviour. Without this we will reload whatever the last FPSIMD state
that was saved for the task was.

Fixes: 40a8e87bb3 ("arm64/sme: Disable ZA and streaming mode when handling signals")
Signed-off-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Link: https://lore.kernel.org/r/20220817182324.638214-3-broonie@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
2022-08-23 11:29:11 +01:00
Mark Brown
7ddcaf78e9 arm64/signal: Raise limit on stack frames
The signal code has a limit of 64K on the size of a stack frame that it
will generate, if this limit is exceeded then a process will be killed if
it receives a signal. Unfortunately with the advent of SME this limit is
too small - the maximum possible size of the ZA register alone is 64K. This
is not an issue for practical systems at present but is easily seen using
virtual platforms.

Raise the limit to 256K, this is substantially more than could be used by
any current architecture extension.

Signed-off-by: Mark Brown <broonie@kernel.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Link: https://lore.kernel.org/r/20220817182324.638214-2-broonie@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
2022-08-23 11:29:11 +01:00
Mark Brown
df07443f47 arm64/signal: Clean up SVE/SME feature checking inconsistency
Currently when restoring signal state we check to see if SVE is supported
in restore_sigframe() but check to see if SVE is supported inside
restore_sve_fpsimd_context(). This makes no real difference since SVE is
always supported in systems with SME but looks a bit untidy and makes
things slightly harder to follow, move the SVE check next to the SME one
in restore_sve_fpsimd_context().

Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20220624172108.555000-1-broonie@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
2022-06-27 10:28:12 +01:00
Linus Torvalds
21873bd66b arm64 fixes for 5.19-rc1:
- Initialise jump labels before setup_machine_fdt(), needed by commit
   f5bda35fba ("random: use static branch for crng_ready()").
 
 - Sparse warnings: missing prototype, incorrect __user annotation.
 
 - Skip SVE kselftest if not sufficient vector lengths supported.
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Merge tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux

Pull arm64 fixes from Catalin Marinas:
 "Most of issues addressed were introduced during this merging window.

   - Initialise jump labels before setup_machine_fdt(), needed by commit
     f5bda35fba ("random: use static branch for crng_ready()").

   - Sparse warnings: missing prototype, incorrect __user annotation.

   - Skip SVE kselftest if not sufficient vector lengths supported"

* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
  kselftest/arm64: signal: Skip SVE signal test if not enough VLs supported
  arm64: Initialize jump labels before setup_machine_fdt()
  arm64: hibernate: Fix syntax errors in comments
  arm64: Remove the __user annotation for the restore_za_context() argument
  ftrace/fgraph: fix increased missing-prototypes warnings
2022-06-03 14:05:34 -07:00
Catalin Marinas
1bec877bdb arm64: Remove the __user annotation for the restore_za_context() argument
The struct user_ctx *user pointer passed to restore_za_context() is not
a user point but a structure containing several __user pointers. Remove
the __user annotation.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Fixes: 39782210eb ("arm64/sme: Implement ZA signal handling")
Reported-by: kernel test robot <lkp@intel.com>
Cc: Mark Brown <broonie@kernel.org>
Reviewed-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20220601171338.2143625-1-catalin.marinas@arm.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2022-06-02 11:55:29 +01:00
Linus Torvalds
cfeb2522c3 Perf events changes for this cycle were:
Platform PMU changes:
 =====================
 
  - x86/intel:
     - Add new Intel Alder Lake and Raptor Lake support
 
  - x86/amd:
     - AMD Zen4 IBS extensions support
     - Add AMD PerfMonV2 support
     - Add AMD Fam19h Branch Sampling support
 
 Generic changes:
 ================
 
  - signal: Deliver SIGTRAP on perf event asynchronously if blocked
 
    Perf instrumentation can be driven via SIGTRAP, but this causes a problem
    when SIGTRAP is blocked by a task & terminate the task.
 
    Allow user-space to request these signals asynchronously (after they get
    unblocked) & also give the information to the signal handler when this
    happens:
 
      " To give user space the ability to clearly distinguish synchronous from
        asynchronous signals, introduce siginfo_t::si_perf_flags and
        TRAP_PERF_FLAG_ASYNC (opted for flags in case more binary information is
        required in future).
 
        The resolution to the problem is then to (a) no longer force the signal
        (avoiding the terminations), but (b) tell user space via si_perf_flags
        if the signal was synchronous or not, so that such signals can be
        handled differently (e.g. let user space decide to ignore or consider
        the data imprecise). "
 
  - Unify/standardize the /sys/devices/cpu/events/* output format.
 
  - Misc fixes & cleanups.
 
 Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Merge tag 'perf-core-2022-05-23' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull perf events updates from Ingo Molnar:
 "Platform PMU changes:

   - x86/intel:
      - Add new Intel Alder Lake and Raptor Lake support

   - x86/amd:
      - AMD Zen4 IBS extensions support
      - Add AMD PerfMonV2 support
      - Add AMD Fam19h Branch Sampling support

  Generic changes:

   - signal: Deliver SIGTRAP on perf event asynchronously if blocked

     Perf instrumentation can be driven via SIGTRAP, but this causes a
     problem when SIGTRAP is blocked by a task & terminate the task.

     Allow user-space to request these signals asynchronously (after
     they get unblocked) & also give the information to the signal
     handler when this happens:

       "To give user space the ability to clearly distinguish
        synchronous from asynchronous signals, introduce
        siginfo_t::si_perf_flags and TRAP_PERF_FLAG_ASYNC (opted for
        flags in case more binary information is required in future).

        The resolution to the problem is then to (a) no longer force the
        signal (avoiding the terminations), but (b) tell user space via
        si_perf_flags if the signal was synchronous or not, so that such
        signals can be handled differently (e.g. let user space decide
        to ignore or consider the data imprecise). "

   - Unify/standardize the /sys/devices/cpu/events/* output format.

   - Misc fixes & cleanups"

* tag 'perf-core-2022-05-23' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (32 commits)
  perf/x86/amd/core: Fix reloading events for SVM
  perf/x86/amd: Run AMD BRS code only on supported hw
  perf/x86/amd: Fix AMD BRS period adjustment
  perf/x86/amd: Remove unused variable 'hwc'
  perf/ibs: Fix comment
  perf/amd/ibs: Advertise zen4_ibs_extensions as pmu capability attribute
  perf/amd/ibs: Add support for L3 miss filtering
  perf/amd/ibs: Use ->is_visible callback for dynamic attributes
  perf/amd/ibs: Cascade pmu init functions' return value
  perf/x86/uncore: Add new Alder Lake and Raptor Lake support
  perf/x86/uncore: Clean up uncore_pci_ids[]
  perf/x86/cstate: Add new Alder Lake and Raptor Lake support
  perf/x86/msr: Add new Alder Lake and Raptor Lake support
  perf/x86: Add new Alder Lake and Raptor Lake support
  perf/amd/ibs: Use interrupt regs ip for stack unwinding
  perf/x86/amd/core: Add PerfMonV2 overflow handling
  perf/x86/amd/core: Add PerfMonV2 counter control
  perf/x86/amd/core: Detect available counters
  perf/x86/amd/core: Detect PerfMonV2 support
  x86/msr: Add PerfCntrGlobal* registers
  ...
2022-05-24 10:59:38 -07:00
Mark Brown
ec0067a63e arm64/sme: Remove _EL0 from name of SVCR - FIXME sysreg.h
The defines for SVCR call it SVCR_EL0 however the architecture calls the
register SVCR with no _EL0 suffix. In preparation for generating the sysreg
definitions rename to match the architecture, no functional change.

Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20220510161208.631259-6-broonie@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2022-05-16 19:50:20 +01:00
Mark Brown
39782210eb arm64/sme: Implement ZA signal handling
Implement support for ZA in signal handling in a very similar way to how
we implement support for SVE registers, using a signal context structure
with optional register state after it. Where present this register state
stores the ZA matrix as a series of horizontal vectors numbered from 0 to
VL/8 in the endinanness independent format used for vectors.

As with SVE we do not allow changes in the vector length during signal
return but we do allow ZA to be enabled or disabled.

Signed-off-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Link: https://lore.kernel.org/r/20220419112247.711548-20-broonie@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2022-04-22 18:51:13 +01:00
Mark Brown
85ed24dad2 arm64/sme: Implement streaming SVE signal handling
When in streaming mode we have the same set of SVE registers as we do in
regular SVE mode with the exception of FFR and the use of the SME vector
length. Provide signal handling for these registers by taking one of the
reserved words in the SVE signal context as a flags field and defining a
flag which is set for streaming mode. When the flag is set the vector
length is set to the streaming mode vector length and we save and
restore streaming mode data. We support entering or leaving streaming
mode based on the value of the flag but do not support changing the
vector length, this is not currently supported SVE signal handling.

We could instead allocate a separate record in the signal frame for the
streaming mode SVE context but this inflates the size of the maximal signal
frame required and adds complication when validating signal frames from
userspace, especially given the current structure of the code.

Any implementation of support for streaming mode vectors in signals will
have some potential for causing issues for applications that attempt to
handle SVE vectors in signals, use streaming mode but do not understand
streaming mode in their signal handling code, it is hard to identify a
case that is clearly better than any other - they all have cases where
they could cause unexpected register corruption or faults.

Signed-off-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Link: https://lore.kernel.org/r/20220419112247.711548-19-broonie@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2022-04-22 18:51:10 +01:00
Mark Brown
40a8e87bb3 arm64/sme: Disable ZA and streaming mode when handling signals
The ABI requires that streaming mode and ZA are disabled when invoking
signal handlers, do this in setup_return() when we prepare the task state
for the signal handler.

Signed-off-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Link: https://lore.kernel.org/r/20220419112247.711548-18-broonie@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2022-04-22 18:51:08 +01:00
Marco Elver
78ed93d72d signal: Deliver SIGTRAP on perf event asynchronously if blocked
With SIGTRAP on perf events, we have encountered termination of
processes due to user space attempting to block delivery of SIGTRAP.
Consider this case:

    <set up SIGTRAP on a perf event>
    ...
    sigset_t s;
    sigemptyset(&s);
    sigaddset(&s, SIGTRAP | <and others>);
    sigprocmask(SIG_BLOCK, &s, ...);
    ...
    <perf event triggers>

When the perf event triggers, while SIGTRAP is blocked, force_sig_perf()
will force the signal, but revert back to the default handler, thus
terminating the task.

This makes sense for error conditions, but not so much for explicitly
requested monitoring. However, the expectation is still that signals
generated by perf events are synchronous, which will no longer be the
case if the signal is blocked and delivered later.

To give user space the ability to clearly distinguish synchronous from
asynchronous signals, introduce siginfo_t::si_perf_flags and
TRAP_PERF_FLAG_ASYNC (opted for flags in case more binary information is
required in future).

The resolution to the problem is then to (a) no longer force the signal
(avoiding the terminations), but (b) tell user space via si_perf_flags
if the signal was synchronous or not, so that such signals can be
handled differently (e.g. let user space decide to ignore or consider
the data imprecise).

The alternative of making the kernel ignore SIGTRAP on perf events if
the signal is blocked may work for some usecases, but likely causes
issues in others that then have to revert back to interception of
sigprocmask() (which we want to avoid). [ A concrete example: when using
breakpoint perf events to track data-flow, in a region of code where
signals are blocked, data-flow can no longer be tracked accurately.
When a relevant asynchronous signal is received after unblocking the
signal, the data-flow tracking logic needs to know its state is
imprecise. ]

Fixes: 97ba62b278 ("perf: Add support for SIGTRAP on perf events")
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Marco Elver <elver@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Tested-by: Dmitry Vyukov <dvyukov@google.com>
Link: https://lore.kernel.org/r/20220404111204.935357-1-elver@google.com
2022-04-22 12:14:05 +02:00
Linus Torvalds
1930a6e739 ptrace: Cleanups for v5.18
This set of changes removes tracehook.h, moves modification of all of
 the ptrace fields inside of siglock to remove races, adds a missing
 permission check to ptrace.c
 
 The removal of tracehook.h is quite significant as it has been a major
 source of confusion in recent years.  Much of that confusion was
 around task_work and TIF_NOTIFY_SIGNAL (which I have now decoupled
 making the semantics clearer).
 
 For people who don't know tracehook.h is a vestiage of an attempt to
 implement uprobes like functionality that was never fully merged, and
 was later superseeded by uprobes when uprobes was merged.  For many
 years now we have been removing what tracehook functionaly a little
 bit at a time.  To the point where now anything left in tracehook.h is
 some weird strange thing that is difficult to understand.
 
 Eric W. Biederman (15):
       ptrace: Move ptrace_report_syscall into ptrace.h
       ptrace/arm: Rename tracehook_report_syscall report_syscall
       ptrace: Create ptrace_report_syscall_{entry,exit} in ptrace.h
       ptrace: Remove arch_syscall_{enter,exit}_tracehook
       ptrace: Remove tracehook_signal_handler
       task_work: Remove unnecessary include from posix_timers.h
       task_work: Introduce task_work_pending
       task_work: Call tracehook_notify_signal from get_signal on all architectures
       task_work: Decouple TIF_NOTIFY_SIGNAL and task_work
       signal: Move set_notify_signal and clear_notify_signal into sched/signal.h
       resume_user_mode: Remove #ifdef TIF_NOTIFY_RESUME in set_notify_resume
       resume_user_mode: Move to resume_user_mode.h
       tracehook: Remove tracehook.h
       ptrace: Move setting/clearing ptrace_message into ptrace_stop
       ptrace: Return the signal to continue with from ptrace_stop
 
 Jann Horn (1):
       ptrace: Check PTRACE_O_SUSPEND_SECCOMP permission on PTRACE_SEIZE
 
 Yang Li (1):
       ptrace: Remove duplicated include in ptrace.c
 
  MAINTAINERS                          |   1 -
  arch/Kconfig                         |   5 +-
  arch/alpha/kernel/ptrace.c           |   5 +-
  arch/alpha/kernel/signal.c           |   4 +-
  arch/arc/kernel/ptrace.c             |   5 +-
  arch/arc/kernel/signal.c             |   4 +-
  arch/arm/kernel/ptrace.c             |  12 +-
  arch/arm/kernel/signal.c             |   4 +-
  arch/arm64/kernel/ptrace.c           |  14 +--
  arch/arm64/kernel/signal.c           |   4 +-
  arch/csky/kernel/ptrace.c            |   5 +-
  arch/csky/kernel/signal.c            |   4 +-
  arch/h8300/kernel/ptrace.c           |   5 +-
  arch/h8300/kernel/signal.c           |   4 +-
  arch/hexagon/kernel/process.c        |   4 +-
  arch/hexagon/kernel/signal.c         |   1 -
  arch/hexagon/kernel/traps.c          |   6 +-
  arch/ia64/kernel/process.c           |   4 +-
  arch/ia64/kernel/ptrace.c            |   6 +-
  arch/ia64/kernel/signal.c            |   1 -
  arch/m68k/kernel/ptrace.c            |   5 +-
  arch/m68k/kernel/signal.c            |   4 +-
  arch/microblaze/kernel/ptrace.c      |   5 +-
  arch/microblaze/kernel/signal.c      |   4 +-
  arch/mips/kernel/ptrace.c            |   5 +-
  arch/mips/kernel/signal.c            |   4 +-
  arch/nds32/include/asm/syscall.h     |   2 +-
  arch/nds32/kernel/ptrace.c           |   5 +-
  arch/nds32/kernel/signal.c           |   4 +-
  arch/nios2/kernel/ptrace.c           |   5 +-
  arch/nios2/kernel/signal.c           |   4 +-
  arch/openrisc/kernel/ptrace.c        |   5 +-
  arch/openrisc/kernel/signal.c        |   4 +-
  arch/parisc/kernel/ptrace.c          |   7 +-
  arch/parisc/kernel/signal.c          |   4 +-
  arch/powerpc/kernel/ptrace/ptrace.c  |   8 +-
  arch/powerpc/kernel/signal.c         |   4 +-
  arch/riscv/kernel/ptrace.c           |   5 +-
  arch/riscv/kernel/signal.c           |   4 +-
  arch/s390/include/asm/entry-common.h |   1 -
  arch/s390/kernel/ptrace.c            |   1 -
  arch/s390/kernel/signal.c            |   5 +-
  arch/sh/kernel/ptrace_32.c           |   5 +-
  arch/sh/kernel/signal_32.c           |   4 +-
  arch/sparc/kernel/ptrace_32.c        |   5 +-
  arch/sparc/kernel/ptrace_64.c        |   5 +-
  arch/sparc/kernel/signal32.c         |   1 -
  arch/sparc/kernel/signal_32.c        |   4 +-
  arch/sparc/kernel/signal_64.c        |   4 +-
  arch/um/kernel/process.c             |   4 +-
  arch/um/kernel/ptrace.c              |   5 +-
  arch/x86/kernel/ptrace.c             |   1 -
  arch/x86/kernel/signal.c             |   5 +-
  arch/x86/mm/tlb.c                    |   1 +
  arch/xtensa/kernel/ptrace.c          |   5 +-
  arch/xtensa/kernel/signal.c          |   4 +-
  block/blk-cgroup.c                   |   2 +-
  fs/coredump.c                        |   1 -
  fs/exec.c                            |   1 -
  fs/io-wq.c                           |   6 +-
  fs/io_uring.c                        |  11 +-
  fs/proc/array.c                      |   1 -
  fs/proc/base.c                       |   1 -
  include/asm-generic/syscall.h        |   2 +-
  include/linux/entry-common.h         |  47 +-------
  include/linux/entry-kvm.h            |   2 +-
  include/linux/posix-timers.h         |   1 -
  include/linux/ptrace.h               |  81 ++++++++++++-
  include/linux/resume_user_mode.h     |  64 ++++++++++
  include/linux/sched/signal.h         |  17 +++
  include/linux/task_work.h            |   5 +
  include/linux/tracehook.h            | 226 -----------------------------------
  include/uapi/linux/ptrace.h          |   2 +-
  kernel/entry/common.c                |  19 +--
  kernel/entry/kvm.c                   |   9 +-
  kernel/exit.c                        |   3 +-
  kernel/livepatch/transition.c        |   1 -
  kernel/ptrace.c                      |  47 +++++---
  kernel/seccomp.c                     |   1 -
  kernel/signal.c                      |  62 +++++-----
  kernel/task_work.c                   |   4 +-
  kernel/time/posix-cpu-timers.c       |   1 +
  mm/memcontrol.c                      |   2 +-
  security/apparmor/domain.c           |   1 -
  security/selinux/hooks.c             |   1 -
  85 files changed, 372 insertions(+), 495 deletions(-)
 
 Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
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Merge tag 'ptrace-cleanups-for-v5.18' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace

Pull ptrace cleanups from Eric Biederman:
 "This set of changes removes tracehook.h, moves modification of all of
  the ptrace fields inside of siglock to remove races, adds a missing
  permission check to ptrace.c

  The removal of tracehook.h is quite significant as it has been a major
  source of confusion in recent years. Much of that confusion was around
  task_work and TIF_NOTIFY_SIGNAL (which I have now decoupled making the
  semantics clearer).

  For people who don't know tracehook.h is a vestiage of an attempt to
  implement uprobes like functionality that was never fully merged, and
  was later superseeded by uprobes when uprobes was merged. For many
  years now we have been removing what tracehook functionaly a little
  bit at a time. To the point where anything left in tracehook.h was
  some weird strange thing that was difficult to understand"

* tag 'ptrace-cleanups-for-v5.18' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace:
  ptrace: Remove duplicated include in ptrace.c
  ptrace: Check PTRACE_O_SUSPEND_SECCOMP permission on PTRACE_SEIZE
  ptrace: Return the signal to continue with from ptrace_stop
  ptrace: Move setting/clearing ptrace_message into ptrace_stop
  tracehook: Remove tracehook.h
  resume_user_mode: Move to resume_user_mode.h
  resume_user_mode: Remove #ifdef TIF_NOTIFY_RESUME in set_notify_resume
  signal: Move set_notify_signal and clear_notify_signal into sched/signal.h
  task_work: Decouple TIF_NOTIFY_SIGNAL and task_work
  task_work: Call tracehook_notify_signal from get_signal on all architectures
  task_work: Introduce task_work_pending
  task_work: Remove unnecessary include from posix_timers.h
  ptrace: Remove tracehook_signal_handler
  ptrace: Remove arch_syscall_{enter,exit}_tracehook
  ptrace: Create ptrace_report_syscall_{entry,exit} in ptrace.h
  ptrace/arm: Rename tracehook_report_syscall report_syscall
  ptrace: Move ptrace_report_syscall into ptrace.h
2022-03-28 17:29:53 -07:00
Will Deacon
8d93b7a242 Merge branch 'for-next/fpsimd' into for-next/core
* for-next/fpsimd:
  arm64: cpufeature: Warn if we attempt to read a zero width field
  arm64: cpufeature: Add missing .field_width for GIC system registers
  arm64: signal: nofpsimd: Do not allocate fp/simd context when not available
  arm64: cpufeature: Always specify and use a field width for capabilities
  arm64: Always use individual bits in CPACR floating point enables
  arm64: Define CPACR_EL1_FPEN similarly to other floating point controls
2022-03-14 19:04:22 +00:00
Eric W. Biederman
03248addad resume_user_mode: Move to resume_user_mode.h
Move set_notify_resume and tracehook_notify_resume into resume_user_mode.h.
While doing that rename tracehook_notify_resume to resume_user_mode_work.

Update all of the places that included tracehook.h for these functions to
include resume_user_mode.h instead.

Update all of the callers of tracehook_notify_resume to call
resume_user_mode_work.

Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lkml.kernel.org/r/20220309162454.123006-12-ebiederm@xmission.com
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2022-03-10 16:51:50 -06:00
Sagar Patel
ee94b5a061 arm64: drop unused includes of <linux/personality.h>
Drop several includes of <linux/personality.h> which are not used.
git-blame indicates they were used at some point, but they're not needed
anymore.

Signed-off-by: Sagar Patel <sagarmp@cs.unc.edu>
Link: https://lore.kernel.org/r/20220307222412.146506-1-sagarmp@cs.unc.edu
Signed-off-by: Will Deacon <will@kernel.org>
2022-03-08 10:23:42 +00:00
David Engraf
0a32c88ddb arm64: signal: nofpsimd: Do not allocate fp/simd context when not available
Commit 6d502b6ba1 ("arm64: signal: nofpsimd: Handle fp/simd context for
signal frames") introduced saving the fp/simd context for signal handling
only when support is available. But setup_sigframe_layout() always
reserves memory for fp/simd context. The additional memory is not touched
because preserve_fpsimd_context() is not called and thus the magic is
invalid.

This may lead to an error when parse_user_sigframe() checks the fp/simd
area and does not find a valid magic number.

Signed-off-by: David Engraf <david.engraf@sysgo.com>
Reviwed-by: Mark Brown <broonie@kernel.org>
Fixes: 6d502b6ba1 ("arm64: signal: nofpsimd: Handle fp/simd context for signal frames")
Cc: <stable@vger.kernel.org> # 5.6.x
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Link: https://lore.kernel.org/r/20220225104008.820289-1-david.engraf@sysgo.com
Signed-off-by: Will Deacon <will@kernel.org>
2022-03-07 21:38:25 +00:00
Mark Rutland
342b380878 arm64: Snapshot thread flags
Some thread flags can be set remotely, and so even when IRQs are disabled,
the flags can change under our feet. Generally this is unlikely to cause a
problem in practice, but it is somewhat unsound, and KCSAN will
legitimately warn that there is a data race.

To avoid such issues, a snapshot of the flags has to be taken prior to
using them. Some places already use READ_ONCE() for that, others do not.

Convert them all to the new flag accessor helpers.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Will Deacon <will@kernel.org>
Acked-by: Paul E. McKenney <paulmck@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Link: https://lore.kernel.org/r/20211129130653.2037928-7-mark.rutland@arm.com
2021-12-01 00:06:44 +01:00
Mark Brown
b5bc00ffdd arm64/sve: Put system wide vector length information into structs
With the introduction of SME we will have a second vector length in the
system, enumerated and configured in a very similar fashion to the
existing SVE vector length.  While there are a few differences in how
things are handled this is a relatively small portion of the overall
code so in order to avoid code duplication we factor out

We create two structs, one vl_info for the static hardware properties
and one vl_config for the runtime configuration, with an array
instantiated for each and update all the users to reference these. Some
accessor functions are provided where helpful for readability, and the
write to set the vector length is put into a function since the system
register being updated needs to be chosen at compile time.

This is a mostly mechanical replacement, further work will be required
to actually make things generic, ensuring that we handle those places
where there are differences properly.

Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20211019172247.3045838-8-broonie@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
2021-10-21 10:18:17 +01:00
Mark Brown
0423eedcf4 arm64/sve: Use accessor functions for vector lengths in thread_struct
In a system with SME there are parallel vector length controls for SVE and
SME vectors which function in much the same way so it is desirable to
share the code for handling them as much as possible. In order to prepare
for doing this add a layer of accessor functions for the various VL related
operations on tasks.

Since almost all current interactions are actually via task->thread rather
than directly with the thread_info the accessors use that. Accessors are
provided for both generic and SVE specific usage, the generic accessors
should be used for cases where register state is being manipulated since
the registers are shared between streaming and regular SVE so we know that
when SME support is implemented we will always have to be in the appropriate
mode already and hence can generalise now.

Since we are using task_struct and we don't want to cause widespread
inclusion of sched.h the acessors are all out of line, it is hoped that
none of the uses are in a sufficiently critical path for this to be an
issue. Those that are most likely to present an issue are in the same
translation unit so hopefully the compiler may be able to inline anyway.

This is purely adding the layer of abstraction, additional work will be
needed to support tasks using SME.

Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20211019172247.3045838-7-broonie@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
2021-10-21 10:18:17 +01:00
Sean Christopherson
a68de80f61 entry: rseq: Call rseq_handle_notify_resume() in tracehook_notify_resume()
Invoke rseq_handle_notify_resume() from tracehook_notify_resume() now
that the two function are always called back-to-back by architectures
that have rseq.  The rseq helper is stubbed out for architectures that
don't support rseq, i.e. this is a nop across the board.

Note, tracehook_notify_resume() is horribly named and arguably does not
belong in tracehook.h as literally every line of code in it has nothing
to do with tracing.  But, that's been true since commit a42c6ded82
("move key_repace_session_keyring() into tracehook_notify_resume()")
first usurped tracehook_notify_resume() back in 2012.  Punt cleaning that
mess up to future patches.

No functional change intended.

Acked-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20210901203030.1292304-3-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-09-22 10:24:01 -04:00
Linus Torvalds
57c78a234e arm64 updates for 5.15:
- Support for 32-bit tasks on asymmetric AArch32 systems (on top of the
   scheduler changes merged via the tip tree).
 
 - More entry.S clean-ups and conversion to C.
 
 - MTE updates: allow a preferred tag checking mode to be set per CPU
   (the overhead of synchronous mode is smaller for some CPUs than
   others); optimisations for kernel entry/exit path; optionally disable
   MTE on the kernel command line.
 
 - Kselftest improvements for SVE and signal handling, PtrAuth.
 
 - Fix unlikely race where a TLBI could use stale ASID on an ASID
   roll-over (found by inspection).
 
 - Miscellaneous fixes: disable trapping of PMSNEVFR_EL1 to higher
   exception levels; drop unnecessary sigdelsetmask() call in the
   signal32 handling; remove BUG_ON when failing to allocate SVE state
   (just signal the process); SYM_CODE annotations.
 
 - Other trivial clean-ups: use macros instead of magic numbers, remove
   redundant returns, typos.
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Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux

Pull arm64 updates from Catalin Marinas:

 - Support for 32-bit tasks on asymmetric AArch32 systems (on top of the
   scheduler changes merged via the tip tree).

 - More entry.S clean-ups and conversion to C.

 - MTE updates: allow a preferred tag checking mode to be set per CPU
   (the overhead of synchronous mode is smaller for some CPUs than
   others); optimisations for kernel entry/exit path; optionally disable
   MTE on the kernel command line.

 - Kselftest improvements for SVE and signal handling, PtrAuth.

 - Fix unlikely race where a TLBI could use stale ASID on an ASID
   roll-over (found by inspection).

 - Miscellaneous fixes: disable trapping of PMSNEVFR_EL1 to higher
   exception levels; drop unnecessary sigdelsetmask() call in the
   signal32 handling; remove BUG_ON when failing to allocate SVE state
   (just signal the process); SYM_CODE annotations.

 - Other trivial clean-ups: use macros instead of magic numbers, remove
   redundant returns, typos.

* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (56 commits)
  arm64: Do not trap PMSNEVFR_EL1
  arm64: mm: fix comment typo of pud_offset_phys()
  arm64: signal32: Drop pointless call to sigdelsetmask()
  arm64/sve: Better handle failure to allocate SVE register storage
  arm64: Document the requirement for SCR_EL3.HCE
  arm64: head: avoid over-mapping in map_memory
  arm64/sve: Add a comment documenting the binutils needed for SVE asm
  arm64/sve: Add some comments for sve_save/load_state()
  kselftest/arm64: signal: Add a TODO list for signal handling tests
  kselftest/arm64: signal: Add test case for SVE register state in signals
  kselftest/arm64: signal: Verify that signals can't change the SVE vector length
  kselftest/arm64: signal: Check SVE signal frame shows expected vector length
  kselftest/arm64: signal: Support signal frames with SVE register data
  kselftest/arm64: signal: Add SVE to the set of features we can check for
  arm64: replace in_irq() with in_hardirq()
  kselftest/arm64: pac: Fix skipping of tests on systems without PAC
  Documentation: arm64: describe asymmetric 32-bit support
  arm64: Remove logic to kill 32-bit tasks on 64-bit-only cores
  arm64: Hook up cmdline parameter to allow mismatched 32-bit EL0
  arm64: Advertise CPUs capable of running 32-bit applications in sysfs
  ...
2021-09-01 15:04:29 -07:00
Linus Torvalds
48983701a1 Merge branch 'siginfo-si_trapno-for-v5.15' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace
Pull siginfo si_trapno updates from Eric Biederman:
 "The full set of si_trapno changes was not appropriate as a fix for the
  newly added SIGTRAP TRAP_PERF, and so I postponed the rest of the
  related cleanups.

  This is the rest of the cleanups for si_trapno that reduces it from
  being a really weird arch special case that is expect to be always
  present (but isn't) on the architectures that support it to being yet
  another field in the _sigfault union of struct siginfo.

  The changes have been reviewed and marinated in linux-next. With the
  removal of this awkward special case new code (like SIGTRAP TRAP_PERF)
  that works across architectures should be easier to write and
  maintain"

* 'siginfo-si_trapno-for-v5.15' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace:
  signal: Rename SIL_PERF_EVENT SIL_FAULT_PERF_EVENT for consistency
  signal: Verify the alignment and size of siginfo_t
  signal: Remove the generic __ARCH_SI_TRAPNO support
  signal/alpha: si_trapno is only used with SIGFPE and SIGTRAP TRAP_UNK
  signal/sparc: si_trapno is only used with SIGILL ILL_ILLTRP
  arm64: Add compile-time asserts for siginfo_t offsets
  arm: Add compile-time asserts for siginfo_t offsets
  sparc64: Add compile-time asserts for siginfo_t offsets
2021-09-01 14:42:36 -07:00
Catalin Marinas
65266a7c6a Merge remote-tracking branch 'tip/sched/arm64' into for-next/core
* tip/sched/arm64: (785 commits)
  Documentation: arm64: describe asymmetric 32-bit support
  arm64: Remove logic to kill 32-bit tasks on 64-bit-only cores
  arm64: Hook up cmdline parameter to allow mismatched 32-bit EL0
  arm64: Advertise CPUs capable of running 32-bit applications in sysfs
  arm64: Prevent offlining first CPU with 32-bit EL0 on mismatched system
  arm64: exec: Adjust affinity for compat tasks with mismatched 32-bit EL0
  arm64: Implement task_cpu_possible_mask()
  sched: Introduce dl_task_check_affinity() to check proposed affinity
  sched: Allow task CPU affinity to be restricted on asymmetric systems
  sched: Split the guts of sched_setaffinity() into a helper function
  sched: Introduce task_struct::user_cpus_ptr to track requested affinity
  sched: Reject CPU affinity changes based on task_cpu_possible_mask()
  cpuset: Cleanup cpuset_cpus_allowed_fallback() use in select_fallback_rq()
  cpuset: Honour task_cpu_possible_mask() in guarantee_online_cpus()
  cpuset: Don't use the cpu_possible_mask as a last resort for cgroup v1
  sched: Introduce task_cpu_possible_mask() to limit fallback rq selection
  sched: Cgroup SCHED_IDLE support
  sched/topology: Skip updating masks for non-online nodes
  Linux 5.14-rc6
  lib: use PFN_PHYS() in devmem_is_allowed()
  ...
2021-08-31 09:10:00 +01:00
Catalin Marinas
1a7f67e618 Merge branch 'for-next/entry' into for-next/core
* for-next/entry:
  : More entry.S clean-ups and conversion to C.
  arm64: entry: call exit_to_user_mode() from C
  arm64: entry: move bulk of ret_to_user to C
  arm64: entry: clarify entry/exit helpers
  arm64: entry: consolidate entry/exit helpers
2021-08-26 11:49:33 +01:00
Mark Brown
7559b7d7d6 arm64/sve: Better handle failure to allocate SVE register storage
Currently we "handle" failure to allocate the SVE register storage by
doing a BUG_ON() and hoping for the best. This is obviously not great and
the memory allocation failure will already be loud enough without the
BUG_ON(). As the comment says it is a corner case but let's try to do a bit
better, remove the BUG_ON() and add code to handle the failure in the
callers.

For the ptrace and signal code we can return -ENOMEM gracefully however
we have no real error reporting path available to us for the SVE access
trap so instead generate a SIGKILL if the allocation fails there. This
at least means that we won't try to soldier on and end up trying to
access the nonexistant state and while it's obviously not ideal for
userspace SIGKILL doesn't allow any handling so minimises the ABI
impact, making it easier to improve the interface later if we come up
with a better idea.

Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20210824153417.18371-1-broonie@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2021-08-24 16:44:30 +01:00
Will Deacon
94f9c00f64 arm64: Remove logic to kill 32-bit tasks on 64-bit-only cores
The scheduler now knows enough about these braindead systems to place
32-bit tasks accordingly, so throw out the safety checks and allow the
ret-to-user path to avoid do_notify_resume() if there is nothing to do.

Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Link: https://lore.kernel.org/r/20210730112443.23245-16-will@kernel.org
2021-08-20 12:33:07 +02:00
Mark Rutland
4d1c2ee270 arm64: entry: move bulk of ret_to_user to C
In `ret_to_user` we perform some conditional work depending on the
thread flags, then perform some IRQ/context tracking which is intended
to balance with the IRQ/context tracking performed in the entry C code.

For simplicity and consistency, it would be preferable to move this all
to C. As a step towards that, this patch moves the conditional work and
IRQ/context tracking into a C helper function. To aid bisectability,
this is called from the `ret_to_user` assembly, and a subsequent patch
will move the call to C code.

As local_daif_mask() handles all necessary tracing and PMR manipulation,
we no longer need to handle this explicitly. As we call
exit_to_user_mode() directly, the `user_enter_irqoff` macro is no longer
used, and can be removed. As enter_from_user_mode() and
exit_to_user_mode() are no longer called from assembly, these can be
made static, and as these are typically very small, they are marked
__always_inline to avoid the overhead of a function call.

For now, enablement of single-step is left in entry.S, and for this we
still need to read the flags in ret_to_user(). It is safe to read this
separately as TIF_SINGLESTEP is not part of _TIF_WORK_MASK.

There should be no functional change as a result of this patch.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: James Morse <james.morse@arm.com>
Cc: Joey Gouly <joey.gouly@arm.com>
Cc: Marc Zyngier <maz@kernel.org>
Cc: Will Deacon <will@kernel.org>
Reviewed-by: Joey Gouly <joey.gouly@arm.com>
Link: https://lore.kernel.org/r/20210802140733.52716-4-mark.rutland@arm.com
[catalin.marinas@arm.com: removed unused gic_prio_kentry_setup macro]
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2021-08-05 14:09:49 +01:00
Mark Rutland
e30e8d46cf arm64: fix compat syscall return truncation
Due to inconsistencies in the way we manipulate compat GPRs, we have a
few issues today:

* For audit and tracing, where error codes are handled as a (native)
  long, negative error codes are expected to be sign-extended to the
  native 64-bits, or they may fail to be matched correctly. Thus a
  syscall which fails with an error may erroneously be identified as
  failing.

* For ptrace, *all* compat return values should be sign-extended for
  consistency with 32-bit arm, but we currently only do this for
  negative return codes.

* As we may transiently set the upper 32 bits of some compat GPRs while
  in the kernel, these can be sampled by perf, which is somewhat
  confusing. This means that where a syscall returns a pointer above 2G,
  this will be sign-extended, but will not be mistaken for an error as
  error codes are constrained to the inclusive range [-4096, -1] where
  no user pointer can exist.

To fix all of these, we must consistently use helpers to get/set the
compat GPRs, ensuring that we never write the upper 32 bits of the
return code, and always sign-extend when reading the return code.  This
patch does so, with the following changes:

* We re-organise syscall_get_return_value() to always sign-extend for
  compat tasks, and reimplement syscall_get_error() atop. We update
  syscall_trace_exit() to use syscall_get_return_value().

* We consistently use syscall_set_return_value() to set the return
  value, ensureing the upper 32 bits are never set unexpectedly.

* As the core audit code currently uses regs_return_value() rather than
  syscall_get_return_value(), we special-case this for
  compat_user_mode(regs) such that this will do the right thing. Going
  forward, we should try to move the core audit code over to
  syscall_get_return_value().

Cc: <stable@vger.kernel.org>
Reported-by: He Zhe <zhe.he@windriver.com>
Reported-by: weiyuchen <weiyuchen3@huawei.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Link: https://lore.kernel.org/r/20210802104200.21390-1-mark.rutland@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
2021-08-03 10:35:03 +01:00
Eric W. Biederman
50ae81305c signal: Verify the alignment and size of siginfo_t
Update the static assertions about siginfo_t to also describe
it's alignment and size.

While investigating if it was possible to add a 64bit field into
siginfo_t[1] it became apparent that the alignment of siginfo_t
is as much a part of the ABI as the size of the structure.

If the alignment changes siginfo_t when embedded in another structure
can move to a different offset.  Which is not acceptable from an ABI
structure.

So document that fact and add static assertions to notify developers
if they change change the alignment by accident.

[1] https://lkml.kernel.org/r/YJEZdhe6JGFNYlum@elver.google.com
Acked-by: Marco Elver <elver@google.com>
v1: https://lkml.kernel.org/r/20210505141101.11519-4-ebiederm@xmission.co
Link: https://lkml.kernel.org/r/875yxaxmyl.fsf_-_@disp2133
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2021-07-23 13:15:31 -05:00
Marco Elver
726e337b64 arm64: Add compile-time asserts for siginfo_t offsets
To help catch ABI breaks at compile-time, add compile-time assertions to
verify the siginfo_t layout.

Link: https://lkml.kernel.org/r/20210505141101.11519-3-ebiederm@xmission.com
Link: https://lkml.kernel.org/r/20210429190734.624918-3-elver@google.com
Link: https://lkml.kernel.org/r/87sg0fxx92.fsf_-_@disp2133
Signed-off-by: Marco Elver <elver@google.com>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2021-07-23 11:57:45 -05:00
Will Deacon
873c3e8977 arm64: Kill 32-bit applications scheduled on 64-bit-only CPUs
Scheduling a 32-bit application on a 64-bit-only CPU is a bad idea.

Ensure that 32-bit applications always take the slow-path when returning
to userspace on a system with mismatched support at EL0, so that we can
avoid trying to run on a 64-bit-only CPU and force a SIGKILL instead.

Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Link: https://lore.kernel.org/r/20210608180313.11502-5-will@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
2021-06-11 13:25:41 +01:00
Mark Rutland
df06824767 arm64: entry: remove redundant IRQ flag tracing
All EL0 returns go via ret_to_user(), which masks IRQs and notifies
lockdep and tracing before calling into do_notify_resume(). Therefore,
there's no need for do_notify_resume() to call trace_hardirqs_off(), and
the comment is stale. The call is simply redundant.

In ret_to_user() we call exit_to_user_mode(), which notifies lockdep and
tracing the IRQs will be enabled in userspace, so there's no need for
el0_svc_common() to call trace_hardirqs_on() before returning. Further,
at the start of ret_to_user() we call trace_hardirqs_off(), so not only
is this redundant, but it is immediately undone.

In addition to being redundant, the trace_hardirqs_on() in
el0_svc_common() leaves lockdep inconsistent with the hardware state,
and is liable to cause issues for any C code or instrumentation
between this and the call to trace_hardirqs_off() which undoes it in
ret_to_user().

This patch removes the redundant tracing calls and associated stale
comments.

Fixes: 23529049c6 ("arm64: entry: fix non-NMI user<->kernel transitions")
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Will Deacon <will@kernel.org>
Cc: James Morse <james.morse@arm.com>
Cc: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20210107145310.44616-1-mark.rutland@arm.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2021-01-13 12:51:30 +00:00