Commit graph

15929 commits

Author SHA1 Message Date
Peter Zijlstra
fc8bd77d64 x86/kexec: Use RIP relative addressing
Normally identity_mapped is not visible to objtool, due to:

  arch/x86/kernel/Makefile:OBJECT_FILES_NON_STANDARD_relocate_kernel_$(BITS).o := y

However, when we want to run objtool on vmlinux.o there is no hiding
it:

  vmlinux.o: warning: objtool: .text+0x4c0f1: unsupported intra-function call

Replace the (i386 inspired) pattern:

	call 1f
  1:	popq %r8
	subq $(1b - relocate_kernel), %r8

With a x86_64 RIP-relative LEA:

	leaq relocate_kernel(%rip), %r8

Suggested-by: Brian Gerst <brgerst@gmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Link: https://lkml.kernel.org/r/20200324160924.143334345@infradead.org
2020-03-25 18:28:27 +01:00
Ingo Molnar
629b3df7ec Merge branch 'x86/cpu' into perf/core, to resolve conflict
Conflicts:
	arch/x86/events/intel/uncore.c

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2020-03-25 15:20:44 +01:00
Qais Yousef
af7aa04683 x86/smp: Replace cpu_up/down() with add/remove_cpu()
The core device API performs extra housekeeping bits that are missing
from directly calling cpu_up/down().

See commit a6717c01dd ("powerpc/rtas: use device model APIs and
serialization during LPM") for an example description of what might go
wrong.

This also prepares to make cpu_up/down() a private interface of the CPU
subsystem.

Signed-off-by: Qais Yousef <qais.yousef@arm.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20200323135110.30522-10-qais.yousef@arm.com
2020-03-25 12:59:35 +01:00
Qiujun Huang
244febbee8 x86/alternatives: Mark text_poke_loc_init() static
The function is only used in this file so make it static.

 [ bp: Massage. ]

Signed-off-by: Qiujun Huang <hqjagain@gmail.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Link: https://lkml.kernel.org/r/1583253732-18988-1-git-send-email-hqjagain@gmail.com
2020-03-25 12:42:35 +01:00
Masahiro Yamada
d198b34f38 .gitignore: add SPDX License Identifier
Add SPDX License Identifier to all .gitignore files.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-25 11:50:48 +01:00
Thomas Gleixner
adefe55e72 x86/kernel: Convert to new CPU match macros
The new macro set has a consistent namespace and uses C99 initializers
instead of the grufty C89 ones.

Get rid the of the local macro wrappers for consistency.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lkml.kernel.org/r/20200320131509.250559388@linutronix.de
2020-03-24 21:28:26 +01:00
Thomas Gleixner
f6d502fcfc x86/cpu/bugs: Convert to new matching macros
The new macro set has a consistent namespace and uses C99 initializers
instead of the grufty C89 ones.

The local wrappers have to stay as they are tailored to tame the hardware
vulnerability mess.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lkml.kernel.org/r/20200320131508.934926587@linutronix.de
2020-03-24 21:22:23 +01:00
Thomas Gleixner
20d437447c x86/cpu: Add consistent CPU match macros
Finding all places which build x86_cpu_id match tables is tedious and the
logic is hidden in lots of differently named macro wrappers.

Most of these initializer macros use plain C89 initializers which rely on
the ordering of the struct members. So new members could only be added at
the end of the struct, but that's ugly as hell and C99 initializers are
really the right thing to use.

Provide a set of macros which:

  - Have a proper naming scheme, starting with X86_MATCH_

  - Use C99 initializers

The set of provided macros are all subsets of the base macro

    X86_MATCH_VENDOR_FAM_MODEL_FEATURE()

which allows to supply all possible selection criteria:

      vendor, family, model, feature

The other macros shorten this to avoid typing all arguments when they are
not needed and would require one of the _ANY constants. They have been
created due to the requirements of the existing usage sites.

Also add a few model constants for Centaur CPUs and QUARK.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lkml.kernel.org/r/20200320131508.826011988@linutronix.de
2020-03-24 21:17:50 +01:00
Alexey Makhalov
8fefe9dacd x86/vmware: Use bool type for vmw_sched_clock
To be aligned with other bool variables.

Signed-off-by: Alexey Makhalov <amakhalov@vmware.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20200323195707.31242-6-amakhalov@vmware.com
2020-03-24 10:29:22 +01:00
Alexey Makhalov
e73a8f38f8 x86/vmware: Enable steal time accounting
Set paravirt_steal_rq_enabled if steal clock present.
paravirt_steal_rq_enabled is used in sched/core.c to adjust task
progress by offsetting stolen time. Use 'no-steal-acc' off switch (share
same name with KVM) to disable steal time accounting.

Signed-off-by: Alexey Makhalov <amakhalov@vmware.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20200323195707.31242-5-amakhalov@vmware.com
2020-03-24 10:06:27 +01:00
Alexey Makhalov
ab02bb3f55 x86/vmware: Add steal time clock support for VMware guests
Steal time is the amount of CPU time needed by a guest virtual machine
that is not provided by the host. Steal time occurs when the host
allocates this CPU time elsewhere, for example, to another guest.

Steal time can be enabled by adding the VM configuration option
stealclock.enable = "TRUE". It is supported by VMs that run hardware
version 13 or newer.

Introduce the VMware steal time infrastructure. The high level code
(such as enabling, disabling and hot-plug routines) was derived from KVM.

 [ Tomer: use READ_ONCE macros and 32bit guests support. ]
 [ bp: Massage. ]

Co-developed-by: Tomer Zeltzer <tomerr90@gmail.com>
Signed-off-by: Alexey Makhalov <amakhalov@vmware.com>
Signed-off-by: Tomer Zeltzer <tomerr90@gmail.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20200323195707.31242-4-amakhalov@vmware.com
2020-03-24 10:04:51 +01:00
Alexey Makhalov
dd735f4707 x86/vmware: Remove vmware_sched_clock_setup()
Move cyc2ns setup logic to separate function.
This separation will allow to use cyc2ns mult/shift pair
not only for the sched_clock but also for other clocks
such as steal_clock.

Signed-off-by: Alexey Makhalov <amakhalov@vmware.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20200323195707.31242-3-amakhalov@vmware.com
2020-03-24 09:31:06 +01:00
Alexey Makhalov
14388ae245 x86/vmware: Make vmware_select_hypercall() __init
vmware_select_hypercall() is used only by the __init
functions, and should be annotated with __init as well.

Signed-off-by: Alexey Makhalov <amakhalov@vmware.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20200323195707.31242-2-amakhalov@vmware.com
2020-03-24 09:26:04 +01:00
Benjamin Thiel
0e79ad863d x86/cpu: Fix a -Wmissing-prototypes warning for init_ia32_feat_ctl()
Add a missing include in order to fix -Wmissing-prototypes warning:

  arch/x86/kernel/cpu/feat_ctl.c:95:6: warning: no previous prototype for ‘init_ia32_feat_ctl’ [-Wmissing-prototypes]
     95 | void init_ia32_feat_ctl(struct cpuinfo_x86 *c)

Signed-off-by: Benjamin Thiel <b.thiel@posteo.de>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20200323105934.26597-1-b.thiel@posteo.de
2020-03-23 12:01:59 +01:00
Wei Huang
077168e241 x86/mce/amd: Add PPIN support for AMD MCE
Newer AMD CPUs support a feature called protected processor
identification number (PPIN). This feature can be detected via
CPUID_Fn80000008_EBX[23].

However, CPUID alone is not enough to read the processor identification
number - MSR_AMD_PPIN_CTL also needs to be configured properly. If, for
any reason, MSR_AMD_PPIN_CTL[PPIN_EN] can not be turned on, such as
disabled in BIOS, the CPU capability bit X86_FEATURE_AMD_PPIN needs to
be cleared.

When the X86_FEATURE_AMD_PPIN capability is available, the
identification number is issued together with the MCE error info in
order to keep track of the source of MCE errors.

 [ bp: Massage. ]

Co-developed-by: Smita Koralahalli Channabasappa <smita.koralahallichannabasappa@amd.com>
Signed-off-by: Smita Koralahalli Channabasappa <smita.koralahallichannabasappa@amd.com>
Signed-off-by: Wei Huang <wei.huang2@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Tony Luck <tony.luck@intel.com>
Link: https://lkml.kernel.org/r/20200321193800.3666964-1-wei.huang2@amd.com
2020-03-22 11:03:47 +01:00
Brian Gerst
ffd75b373f x86: Remove unneeded includes
Clean up includes of and in <asm/syscalls.h>

Signed-off-by: Brian Gerst <brgerst@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20200313195144.164260-19-brgerst@gmail.com
2020-03-21 16:03:25 +01:00
Brian Gerst
121b32a58a x86/entry/32: Use IA32-specific wrappers for syscalls taking 64-bit arguments
For the 32-bit syscall interface, 64-bit arguments (loff_t) are passed via
a pair of 32-bit registers.  These register pairs end up in consecutive stack
slots, which matches the C ABI for 64-bit arguments.  But when accessing the
registers directly from pt_regs, the wrapper needs to manually reassemble the
64-bit value.  These wrappers already exist for 32-bit compat, so make them
available to 32-bit native in preparation for enabling pt_regs-based syscalls.

Signed-off-by: Brian Gerst <brgerst@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Dominik Brodowski <linux@dominikbrodowski.net>
Link: https://lkml.kernel.org/r/20200313195144.164260-16-brgerst@gmail.com
2020-03-21 16:03:24 +01:00
Brian Gerst
0872098804 x86/entry: Move max syscall number calculation to syscallhdr.sh
Instead of using an array in asm-offsets to calculate the max syscall
number, calculate it when writing out the syscall headers.

Signed-off-by: Brian Gerst <brgerst@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20200313195144.164260-9-brgerst@gmail.com
2020-03-21 16:03:21 +01:00
Brian Gerst
27dd84fafc x86/entry/64: Use syscall wrappers for x32_rt_sigreturn
Add missing syscall wrapper for x32_rt_sigreturn().

Signed-off-by: Brian Gerst <brgerst@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Dominik Brodowski <linux@dominikbrodowski.net>
Reviewed-by: Andy Lutomirski <luto@kernel.org>
Link: https://lkml.kernel.org/r/20200313195144.164260-6-brgerst@gmail.com
2020-03-21 16:03:20 +01:00
afzal mohammed
4dd2a1b92b x86: Replace setup_irq() by request_irq()
request_irq() is preferred over setup_irq(). The early boot setup_irq()
invocations happen either via 'init_IRQ()' or 'time_init()', while
memory allocators are ready by 'mm_init()'.

setup_irq() was required in old kernels when allocators were not ready by
the time early interrupts were initialized.

Hence replace setup_irq() by request_irq().

[ tglx: Use a local variable and get rid of the line break. Tweak the
  	comment a bit ]

Signed-off-by: afzal mohammed <afzal.mohd.ma@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/17f85021f6877650a5b09e0212d88323e6a30fd0.1582471508.git.afzal.mohd.ma@gmail.com
2020-03-21 15:15:47 +01:00
Peter Zijlstra
d8a7386897 x86/optprobe: Fix OPTPROBE vs UACCESS
While looking at an objtool UACCESS warning, it suddenly occurred to me
that it is entirely possible to have an OPTPROBE right in the middle of
an UACCESS region.

In this case we must of course clear FLAGS.AC while running the KPROBE.
Luckily the trampoline already saves/restores [ER]FLAGS, so all we need
to do is inject a CLAC. Unfortunately we cannot use ALTERNATIVE() in the
trampoline text, so we have to frob that manually.

Fixes: ca0bbc70f147 ("sched/x86_64: Don't save flags on context switch")
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Link: https://lkml.kernel.org/r/20200305092130.GU2596@hirez.programming.kicks-ass.net
2020-03-20 13:06:22 +01:00
Guenter Roeck
bac59d18c7 x86/setup: Fix static memory detection
When booting x86 images in qemu, the following warning is seen randomly
if DEBUG_LOCKDEP is enabled.

  WARNING: CPU: 0 PID: 1 at kernel/locking/lockdep.c:1119
	  lockdep_register_key+0xc0/0x100

static_obj() returns true if an address is between _stext and _end.

On x86, this includes the brk memory space. Problem is that this memory
block is not static on x86; its unused portions are released after init
and can be allocated. This results in the observed warning if a lockdep
object is allocated from this memory.

Solve the problem by implementing arch_is_kernel_initmem_freed() for
x86 and have it return true if an address is within the released memory
range.

The same problem was solved for s390 with commit

  7a5da02de8 ("locking/lockdep: check for freed initmem in static_obj()"),

which introduced arch_is_kernel_initmem_freed().

Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200131021159.9178-1-linux@roeck-us.net
2020-03-19 11:58:13 +01:00
Al Viro
39f16c1c0f x86: get rid of put_user_try in {ia32,x32}_setup_rt_frame()
Straightforward, except for compat_save_altstack_ex() stuck in those.
Replace that thing with an analogue that would use unsafe_put_user()
instead of put_user_ex() (called unsafe_compat_save_altstack()) and
be done with that...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-03-19 00:37:49 -04:00
Al Viro
9f855c085f x86: switch setup_sigcontext() to unsafe_put_user()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-03-18 20:39:02 -04:00
Al Viro
a37d01ead4 x86: switch save_v86_state() to unsafe_put_user()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-03-18 20:36:01 -04:00
Al Viro
3add42c29c x86: get rid of get_user_ex() in restore_sigcontext()
Just do copyin into a local struct and be done with that - we are
on a shallow stack here.

[reworked by tglx, removing the macro horrors while we are touching that]

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-03-18 20:22:40 -04:00
Al Viro
c63aad695d vm86: get rid of get_user_ex() use
Just do a copyin of what we want into a local variable and
be done with that.  We are guaranteed to be on shallow stack
here...

Note that conditional expression for range passed to access_ok()
in mainline had been pointless all along - the only difference
between vm86plus_struct and vm86_struct is that the former has
one extra field in the end and when we get to copyin of that
field (conditional upon 'plus' argument), we use copy_from_user().
Moreover, all fields starting with ->int_revectored are copied
that way, so we only need that check (be it done by access_ok()
or by user_access_begin()) only on the beginning of the structure -
the fields that used to be covered by that get_user_try() block.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-03-18 20:04:00 -04:00
Al Viro
71c3313a38 x86: switch sigframe sigset handling to explict __get_user()/__put_user()
... and consolidate the definition of sigframe_ia32->extramask - it's
always a 1-element array of 32bit unsigned.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-03-18 15:29:54 -04:00
Borislav Petkov
19d33357ec x86/amd_nb, char/amd64-agp: Use amd_nb_num() accessor
... to find whether there are northbridges present on the
system. Convert the last forgotten user and therefore, unexport
amd_nb_misc_ids[] too.

Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Michal Kubecek <mkubecek@suse.cz>
Cc: Yazen Ghannam <yazen.ghannam@amd.com>
Link: https://lkml.kernel.org/r/20200316150725.925-1-bp@alien8.de
2020-03-17 10:25:58 +01:00
Linus Torvalds
ec181b7f30 Two fixes for x86:
- Map EFI runtime service data as encrypted when SEV is enabled otherwise
     e.g. SMBIOS data cannot be properly decoded by dmidecode.
 
   - Remove the warning in the vector management code which triggered when a
     managed interrupt affinity changed outside of a CPU hotplug
     operation. The warning was correct until the recent core code change
     that introduced a CPU isolation feature which needs to migrate managed
     interrupts away from online CPUs under certain conditions to achieve the
     isolation.
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Merge tag 'x86-urgent-2020-03-15' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 fixes from Thomas Gleixner:
 "Two fixes for x86:

   - Map EFI runtime service data as encrypted when SEV is enabled.

     Otherwise e.g. SMBIOS data cannot be properly decoded by dmidecode.

   - Remove the warning in the vector management code which triggered
     when a managed interrupt affinity changed outside of a CPU hotplug
     operation.

     The warning was correct until the recent core code change that
     introduced a CPU isolation feature which needs to migrate managed
     interrupts away from online CPUs under certain conditions to
     achieve the isolation"

* tag 'x86-urgent-2020-03-15' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/vector: Remove warning on managed interrupt migration
  x86/ioremap: Map EFI runtime services data as encrypted for SEV
2020-03-15 12:52:56 -07:00
Linus Torvalds
52ac3777fc Two RAS related fixes:
- Shut down the per CPU thermal throttling poll work properly when a CPU
     goes offline. The missing shutdown caused the poll work to be migrated
     to a unbound worker which triggered warnings about the usage of
     smp_processor_id() in preemptible context
 
   - Fix the PPIN feature initialization which missed to enable the
     functionality when PPIN_CTL was enabled but the MSR locked against
     updates.
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Merge tag 'ras-urgent-2020-03-15' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull RAS fixes from Thomas Gleixner:
 "Two RAS related fixes:

   - Shut down the per CPU thermal throttling poll work properly when a
     CPU goes offline.

     The missing shutdown caused the poll work to be migrated to a
     unbound worker which triggered warnings about the usage of
     smp_processor_id() in preemptible context

   - Fix the PPIN feature initialization which missed to enable the
     functionality when PPIN_CTL was enabled but the MSR locked against
     updates"

* tag 'ras-urgent-2020-03-15' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/mce: Fix logic and comments around MSR_PPIN_CTL
  x86/mce/therm_throt: Undo thermal polling properly on CPU offline
2020-03-15 12:44:23 -07:00
Jan Engelhardt
ecb9c79099 acpi/x86: ignore unspecified bit positions in the ACPI global lock field
The value in "new" is constructed from "old" such that all bits defined
as reserved by the ACPI spec[1] are left untouched. But if those bits
do not happen to be all zero, "new < 3" will not evaluate to true.

The firmware of the laptop(s) Medion MD63490 / Akoya P15648 comes with
garbage inside the "FACS" ACPI table. The starting value is
old=0x4944454d, therefore new=0x4944454e, which is >= 3. Mask off
the reserved bits.

[1] https://uefi.org/sites/default/files/resources/ACPI_6_2.pdf

Link: https://bugzilla.kernel.org/show_bug.cgi?id=206553
Cc: All applicable <stable@vger.kernel.org>
Signed-off-by: Jan Engelhardt <jengelh@inai.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-03-14 10:41:56 +01:00
Alex Hung
1ffb8d032d acpi/x86: add a kernel parameter to disable ACPI BGRT
BGRT is for displaying seamless OEM logo from booting to login screen;
however, this mechanism does not always work well on all configurations
and the OEM logo can be displayed multiple times. This looks worse than
without BGRT enabled.

This patch adds a kernel parameter to disable BGRT in boot time. This is
easier than re-compiling a kernel with CONFIG_ACPI_BGRT disabled.

Signed-off-by: Alex Hung <alex.hung@canonical.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-03-14 10:36:49 +01:00
Alexey Dobriyan
fa0fca68e1 x86/acpi: make "asmlinkage" part first thing in the function definition
g++ insists that function declaration must start with extern "C"
(which asmlinkage expands to).

gcc doesn't care.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-03-14 10:29:07 +01:00
Peter Xu
469ff207b4 x86/vector: Remove warning on managed interrupt migration
The vector management code assumes that managed interrupts cannot be
migrated away from an online CPU. free_moved_vector() has a WARN_ON_ONCE()
which triggers when a managed interrupt vector association on a online CPU
is cleared. The CPU offline code uses a different mechanism which cannot
trigger this.

This assumption is not longer correct because the new CPU isolation feature
which affects the placement of managed interrupts must be able to move a
managed interrupt away from an online CPU.

There are two reasons why this can happen:

  1) When the interrupt is activated the affinity mask which was
     established in irq_create_affinity_masks() is handed in to
     the vector allocation code. This mask contains all CPUs to which
     the interrupt can be made affine to, but this does not take the
     CPU isolation 'managed_irq' mask into account.

     When the interrupt is finally requested by the device driver then the
     affinity is checked again and the CPU isolation 'managed_irq' mask is
     taken into account, which moves the interrupt to a non-isolated CPU if
     possible.

  2) The interrupt can be affine to an isolated CPU because the
     non-isolated CPUs in the calculated affinity mask are not online.

     Once a non-isolated CPU which is in the mask comes online the
     interrupt is migrated to this non-isolated CPU

In both cases the regular online migration mechanism is used which triggers
the WARN_ON_ONCE() in free_moved_vector().

Case #1 could have been addressed by taking the isolation mask into
account, but that would require a massive code change in the activation
logic and the eventual migration event was accepted as a reasonable
tradeoff when the isolation feature was developed. But even if #1 would be
addressed, #2 would still trigger it.

Of course the warning in free_moved_vector() was overlooked at that time
and the above two cases which have been discussed during patch review have
obviously never been tested before the final submission.

So keep it simple and remove the warning.

[ tglx: Rewrote changelog and added a comment to free_moved_vector() ]

Fixes: 11ea68f553 ("genirq, sched/isolation: Isolate from handling managed interrupts")
Signed-off-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ming Lei <ming.lei@redhat.com>                                                                                                                                                                       
Link: https://lkml.kernel.org/r/20200312205830.81796-1-peterx@redhat.com
2020-03-13 15:29:26 +01:00
Nayna Jain
9e2b4be377 ima: add a new CONFIG for loading arch-specific policies
Every time a new architecture defines the IMA architecture specific
functions - arch_ima_get_secureboot() and arch_ima_get_policy(), the IMA
include file needs to be updated. To avoid this "noise", this patch
defines a new IMA Kconfig IMA_SECURE_AND_OR_TRUSTED_BOOT option, allowing
the different architectures to select it.

Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Nayna Jain <nayna@linux.ibm.com>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Acked-by: Philipp Rudo <prudo@linux.ibm.com> (s390)
Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-03-12 07:43:57 -04:00
Kim Phillips
753039ef8b x86/cpu/amd: Call init_amd_zn() om Family 19h processors too
Family 19h CPUs are Zen-based and still share most architectural
features with Family 17h CPUs, and therefore still need to call
init_amd_zn() e.g., to set the RECLAIM_DISTANCE override.

init_amd_zn() also sets X86_FEATURE_ZEN, which today is only used
in amd_set_core_ssb_state(), which isn't called on some late
model Family 17h CPUs, nor on any Family 19h CPUs:
X86_FEATURE_AMD_SSBD replaces X86_FEATURE_LS_CFG_SSBD on those
later model CPUs, where the SSBD mitigation is done via the
SPEC_CTRL MSR instead of the LS_CFG MSR.

Family 19h CPUs also don't have the erratum where the CPB feature
bit isn't set, but that code can stay unchanged and run safely
on Family 19h.

Signed-off-by: Kim Phillips <kim.phillips@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20200311191451.13221-1-kim.phillips@amd.com
2020-03-12 12:13:44 +01:00
Hans de Goede
fac01d1172 x86/tsc_msr: Make MSR derived TSC frequency more accurate
The "Intel 64 and IA-32 Architectures Software Developer’s Manual Volume 4:
Model-Specific Registers" has the following table for the values from
freq_desc_byt:

   000B: 083.3 MHz
   001B: 100.0 MHz
   010B: 133.3 MHz
   011B: 116.7 MHz
   100B: 080.0 MHz

Notice how for e.g the 83.3 MHz value there are 3 significant digits, which
translates to an accuracy of a 1000 ppm, where as a typical crystal
oscillator is 20 - 100 ppm, so the accuracy of the frequency format used in
the Software Developer’s Manual is not really helpful.

As far as we know Bay Trail SoCs use a 25 MHz crystal and Cherry Trail
uses a 19.2 MHz crystal, the crystal is the source clock for a root PLL
which outputs 1600 and 100 MHz. It is unclear if the root PLL outputs are
used directly by the CPU clock PLL or if there is another PLL in between.

This does not matter though, we can model the chain of PLLs as a single PLL
with a quotient equal to the quotients of all PLLs in the chain multiplied.

So we can create a simplified model of the CPU clock setup using a
reference clock of 100 MHz plus a quotient which gets us as close to the
frequency from the SDM as possible.

For the 83.3 MHz example from above this would give 100 MHz * 5 / 6 = 83
and 1/3 MHz, which matches exactly what has been measured on actual
hardware.

Use a simplified PLL model with a reference clock of 100 MHz for all Bay
and Cherry Trail models.

This has been tested on the following models:

              CPU freq before:        CPU freq after:
Intel N2840   2165.800 MHz            2166.667 MHz
Intel Z3736   1332.800 MHz            1333.333 MHz
Intel Z3775   1466.300 MHz            1466.667 MHz
Intel Z8350   1440.000 MHz            1440.000 MHz
Intel Z8750   1600.000 MHz            1600.000 MHz

This fixes the time drifting by about 1 second per hour (20 - 30 seconds
per day) on (some) devices which rely on the tsc_msr.c code to determine
the TSC frequency.

Reported-by: Vipul Kumar <vipulk0511@gmail.com>
Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20200223140610.59612-3-hdegoede@redhat.com
2020-03-11 22:57:40 +01:00
Hans de Goede
c8810e2ffc x86/tsc_msr: Fix MSR_FSB_FREQ mask for Cherry Trail devices
According to the "Intel 64 and IA-32 Architectures Software Developer's
Manual Volume 4: Model-Specific Registers" on Cherry Trail (Airmont)
devices the 4 lowest bits of the MSR_FSB_FREQ mask indicate the bus freq
unlike on e.g. Bay Trail where only the lowest 3 bits are used.

This is also the reason why MAX_NUM_FREQS is defined as 9, since Cherry
Trail SoCs have 9 possible frequencies, so the lo value from the MSR needs
to be masked with 0x0f, not with 0x07 otherwise the 9th frequency will get
interpreted as the 1st.

Bump MAX_NUM_FREQS to 16 to avoid any possibility of addressing the array
out of bounds and makes the mask part of the cpufreq struct so it can be
set it per model.

While at it also log an error when the index points to an uninitialized
part of the freqs lookup-table.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20200223140610.59612-2-hdegoede@redhat.com
2020-03-11 22:57:39 +01:00
Hans de Goede
812c2d7506 x86/tsc_msr: Use named struct initializers
Use named struct initializers for the freq_desc struct-s initialization
and change the "u8 msr_plat" to a "bool use_msr_plat" to make its meaning
more clear instead of relying on a comment to explain it.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20200223140610.59612-1-hdegoede@redhat.com
2020-03-11 22:57:39 +01:00
Tony Luck
d8ecca4043 x86/mce/dev-mcelog: Dynamically allocate space for machine check records
We have had a hard coded limit of 32 machine check records since the
dawn of time.  But as numbers of cores increase, it is possible for
more than 32 errors to be reported before a user process reads from
/dev/mcelog. In this case the additional errors are lost.

Keep 32 as the minimum. But tune the maximum value up based on the
number of processors.

Signed-off-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20200218184408.GA23048@agluck-desk2.amr.corp.intel.com
2020-03-10 10:25:14 +01:00
Thomas Gleixner
008f1d60fe x86/apic/vector: Force interupt handler invocation to irq context
Sathyanarayanan reported that the PCI-E AER error injection mechanism
can result in a NULL pointer dereference in apic_ack_edge():

 BUG: unable to handle kernel NULL pointer dereference at 0000000000000078
 RIP: 0010:apic_ack_edge+0x1e/0x40
 Call Trace:
   handle_edge_irq+0x7d/0x1e0
   generic_handle_irq+0x27/0x30
   aer_inject_write+0x53a/0x720

It crashes in irq_complete_move() which dereferences get_irq_regs() which
is obviously NULL when this is called from non interrupt context.

Of course the pointer could be checked, but that just papers over the real
issue. Invoking the low level interrupt handling mechanism from random code
can wreckage the fragile interrupt affinity mechanism of x86 as interrupts
can only be moved in interrupt context or with special care when a CPU goes
offline and the move has to be enforced.

In the best case this triggers the warning in the MSI affinity setter, but
if the call happens on the correct CPU it just corrupts state and might
prevent further interrupt delivery for the affected device.

Mark the APIC interrupts as unsuitable for being invoked in random contexts.

This prevents the AER injection from proliferating the wreckage, but that's
less broken than the current state of affairs and more correct than just
papering over the problem by sprinkling random checks all over the place
and silently corrupting state.

Reported-by: sathyanarayanan.kuppuswamy@linux.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20200306130623.684591280@linutronix.de
2020-03-08 11:06:40 +01:00
Arvind Sankar
8acf63efa1 efi/x86: Avoid using code32_start
code32_start is meant for 16-bit real-mode bootloaders to inform the
kernel where the 32-bit protected mode code starts. Nothing in the
protected mode kernel except the EFI stub uses it.

efi_main() currently returns boot_params, with code32_start set inside it
to tell efi_stub_entry() where startup_32 is located. Since it was invoked
by efi_stub_entry() in the first place, boot_params is already known.
Return the address of startup_32 instead.

This will allow a 64-bit kernel to live above 4Gb, for example, and it's
cleaner as well.

Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20200301230436.2246909-5-nivedita@alum.mit.edu
Link: https://lore.kernel.org/r/20200308080859.21568-13-ardb@kernel.org
2020-03-08 09:58:17 +01:00
Ingo Molnar
6120681bdf Merge branch 'efi/urgent' into efi/core, to pick up fixes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2020-03-08 09:57:58 +01:00
Ingo Molnar
1b10d388d0 Merge branch 'linus' into sched/core, to pick up fixes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2020-03-06 12:49:56 +01:00
Linus Torvalds
2873dc2547 Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Ingo Molnar:
 "Misc fixes: a pkeys fix for a bug that triggers with weird BIOS
  settings, and two Xen PV fixes: a paravirt interface fix, and
  pagetable dumping fix"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/mm: Fix dump_pagetables with Xen PV
  x86/ioperm: Add new paravirt function update_io_bitmap()
  x86/pkeys: Manually set X86_FEATURE_OSPKE to preserve existing changes
2020-03-02 06:54:54 -06:00
Linus Torvalds
f853ed90e2 More bugfixes, including a few remaining "make W=1" issues such
as too large frame sizes on some configurations.  On the
 ARM side, the compiler was messing up shadow stacks between
 EL1 and EL2 code, which is easily fixed with __always_inline.
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull KVM fixes from Paolo Bonzini:
 "More bugfixes, including a few remaining "make W=1" issues such as too
  large frame sizes on some configurations.

  On the ARM side, the compiler was messing up shadow stacks between EL1
  and EL2 code, which is easily fixed with __always_inline"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
  KVM: VMX: check descriptor table exits on instruction emulation
  kvm: x86: Limit the number of "kvm: disabled by bios" messages
  KVM: x86: avoid useless copy of cpufreq policy
  KVM: allow disabling -Werror
  KVM: x86: allow compiling as non-module with W=1
  KVM: Pre-allocate 1 cpumask variable per cpu for both pv tlb and pv ipis
  KVM: Introduce pv check helpers
  KVM: let declaration of kvm_get_running_vcpus match implementation
  KVM: SVM: allocate AVIC data structures based on kvm_amd module parameter
  arm64: Ask the compiler to __always_inline functions used by KVM at HYP
  KVM: arm64: Define our own swab32() to avoid a uapi static inline
  KVM: arm64: Ask the compiler to __always_inline functions used at HYP
  kvm: arm/arm64: Fold VHE entry/exit work into kvm_vcpu_run_vhe()
  KVM: arm/arm64: Fix up includes for trace.h
2020-03-01 15:16:35 -06:00
Juergen Gross
99bcd4a6e5 x86/ioperm: Add new paravirt function update_io_bitmap()
Commit 111e7b15cf ("x86/ioperm: Extend IOPL config to control ioperm()
as well") reworked the iopl syscall to use I/O bitmaps.

Unfortunately this broke Xen PV domains using that syscall as there is
currently no I/O bitmap support in PV domains.

Add I/O bitmap support via a new paravirt function update_io_bitmap which
Xen PV domains can use to update their I/O bitmaps via a hypercall.

Fixes: 111e7b15cf ("x86/ioperm: Extend IOPL config to control ioperm() as well")
Reported-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Cc: <stable@vger.kernel.org> # 5.5
Link: https://lkml.kernel.org/r/20200218154712.25490-1-jgross@suse.com
2020-02-29 12:43:09 +01:00
Wanpeng Li
8a9442f49c KVM: Pre-allocate 1 cpumask variable per cpu for both pv tlb and pv ipis
Nick Desaulniers Reported:

  When building with:
  $ make CC=clang arch/x86/ CFLAGS=-Wframe-larger-than=1000
  The following warning is observed:
  arch/x86/kernel/kvm.c:494:13: warning: stack frame size of 1064 bytes in
  function 'kvm_send_ipi_mask_allbutself' [-Wframe-larger-than=]
  static void kvm_send_ipi_mask_allbutself(const struct cpumask *mask, int
  vector)
              ^
  Debugging with:
  https://github.com/ClangBuiltLinux/frame-larger-than
  via:
  $ python3 frame_larger_than.py arch/x86/kernel/kvm.o \
    kvm_send_ipi_mask_allbutself
  points to the stack allocated `struct cpumask newmask` in
  `kvm_send_ipi_mask_allbutself`. The size of a `struct cpumask` is
  potentially large, as it's CONFIG_NR_CPUS divided by BITS_PER_LONG for
  the target architecture. CONFIG_NR_CPUS for X86_64 can be as high as
  8192, making a single instance of a `struct cpumask` 1024 B.

This patch fixes it by pre-allocate 1 cpumask variable per cpu and use it for
both pv tlb and pv ipis..

Reported-by: Nick Desaulniers <ndesaulniers@google.com>
Acked-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Wanpeng Li <wanpengli@tencent.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-02-28 10:34:25 +01:00
Wanpeng Li
a262bca3ab KVM: Introduce pv check helpers
Introduce some pv check helpers for consistency.

Suggested-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Wanpeng Li <wanpengli@tencent.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-02-28 10:34:19 +01:00
Tony Luck
59b5809655 x86/mce: Fix logic and comments around MSR_PPIN_CTL
There are two implemented bits in the PPIN_CTL MSR:

Bit 0: LockOut (R/WO)
      Set 1 to prevent further writes to MSR_PPIN_CTL.

Bit 1: Enable_PPIN (R/W)
       If 1, enables MSR_PPIN to be accessible using RDMSR.
       If 0, an attempt to read MSR_PPIN will cause #GP.

So there are four defined values:
	0: PPIN is disabled, PPIN_CTL may be updated
	1: PPIN is disabled. PPIN_CTL is locked against updates
	2: PPIN is enabled. PPIN_CTL may be updated
	3: PPIN is enabled. PPIN_CTL is locked against updates

Code would only enable the X86_FEATURE_INTEL_PPIN feature for case "2".
When it should have done so for both case "2" and case "3".

Fix the final test to just check for the enable bit. Also fix some of
the other comments in this function.

Fixes: 3f5a7896a5 ("x86/mce: Include the PPIN in MCE records when available")
Signed-off-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: <stable@vger.kernel.org>
Link: https://lkml.kernel.org/r/20200226011737.9958-1-tony.luck@intel.com
2020-02-27 21:36:42 +01:00
Sean Christopherson
735a6dd022 x86/pkeys: Manually set X86_FEATURE_OSPKE to preserve existing changes
Explicitly set X86_FEATURE_OSPKE via set_cpu_cap() instead of calling
get_cpu_cap() to pull the feature bit from CPUID after enabling CR4.PKE.
Invoking get_cpu_cap() effectively wipes out any {set,clear}_cpu_cap()
changes that were made between this_cpu->c_init() and setup_pku(), as
all non-synthetic feature words are reinitialized from the CPU's CPUID
values.

Blasting away capability updates manifests most visibility when running
on a VMX capable CPU, but with VMX disabled by BIOS.  To indicate that
VMX is disabled, init_ia32_feat_ctl() clears X86_FEATURE_VMX, using
clear_cpu_cap() instead of setup_clear_cpu_cap() so that KVM can report
which CPU is misconfigured (KVM needs to probe every CPU anyways).
Restoring X86_FEATURE_VMX from CPUID causes KVM to think VMX is enabled,
ultimately leading to an unexpected #GP when KVM attempts to do VMXON.

Arguably, init_ia32_feat_ctl() should use setup_clear_cpu_cap() and let
KVM figure out a different way to report the misconfigured CPU, but VMX
is not the only feature bit that is affected, i.e. there is precedent
that tweaking feature bits via {set,clear}_cpu_cap() after ->c_init()
is expected to work.  Most notably, x86_init_rdrand()'s clearing of
X86_FEATURE_RDRAND when RDRAND malfunctions is also overwritten.

Fixes: 0697694564 ("x86/mm/pkeys: Actually enable Memory Protection Keys in the CPU")
Reported-by: Jacob Keller <jacob.e.keller@intel.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Dave Hansen <dave.hansen@linux.intel.com>
Tested-by: Jacob Keller <jacob.e.keller@intel.com>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20200226231615.13664-1-sean.j.christopherson@intel.com
2020-02-27 19:02:45 +01:00
Andy Lutomirski
65c668f5fa x86/traps: Stop using ist_enter/exit() in do_int3()
#BP is not longer using IST and using ist_enter() and ist_exit() makes it
harder to change ist_enter() and ist_exit()'s behavior.  Instead open-code
the very small amount of required logic.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Reviewed-by: Andy Lutomirski <luto@kernel.org>
Link: https://lkml.kernel.org/r/20200225220217.150607679@linutronix.de
2020-02-27 15:28:39 +01:00
Thomas Gleixner
17dbedb5da x86/irq: Remove useless return value from do_IRQ()
Nothing is using it.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Reviewed-by: Andy Lutomirski <luto@kernel.org>
Link: https://lkml.kernel.org/r/20200225220216.826870369@linutronix.de
2020-02-27 14:48:40 +01:00
Thomas Gleixner
d244d0e195 x86/traps: Document do_spurious_interrupt_bug()
Add a comment which explains why this empty handler for a reserved vector
exists.

Requested-by: Josh Poimboeuf <jpoimboe@redhat.com>

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Reviewed-by: Andy Lutomirski <luto@kernel.org>
Link: https://lkml.kernel.org/r/20200225220216.624165786@linutronix.de
2020-02-27 14:48:40 +01:00
Thomas Gleixner
e039dd8159 x86/traps: Remove pointless irq enable from do_spurious_interrupt_bug()
That function returns immediately after conditionally reenabling interrupts which
is more than pointless and requires the ASM code to disable interrupts again.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Sean Christopherson <sean.j.christopherson@intel.com>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Reviewed-by: Andy Lutomirski <luto@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20191023123117.871608831@linutronix.de
Link: https://lkml.kernel.org/r/20200225220216.518575042@linutronix.de
2020-02-27 14:48:39 +01:00
Thomas Gleixner
840371bea1 x86/entry/32: Force MCE through do_mce()
Remove the pointless difference between 32 and 64 bit to make further
unifications simpler.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Reviewed-by: Andy Lutomirski <luto@kernel.org>
Link: https://lkml.kernel.org/r/20200225220216.428188397@linutronix.de
2020-02-27 14:48:39 +01:00
Andy Lutomirski
55ba18d6ed x86/mce: Disable tracing and kprobes on do_machine_check()
do_machine_check() can be raised in almost any context including the most
fragile ones. Prevent kprobes and tracing.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Reviewed-by: Andy Lutomirski <luto@kernel.org>
Link: https://lkml.kernel.org/r/20200225220216.315548935@linutronix.de
2020-02-27 14:48:39 +01:00
Ingo Molnar
e9765680a3 EFI updates for v5.7:
This time, the set of changes for the EFI subsystem is much larger than
 usual. The main reasons are:
 - Get things cleaned up before EFI support for RISC-V arrives, which will
   increase the size of the validation matrix, and therefore the threshold to
   making drastic changes,
 - After years of defunct maintainership, the GRUB project has finally started
   to consider changes from the distros regarding UEFI boot, some of which are
   highly specific to the way x86 does UEFI secure boot and measured boot,
   based on knowledge of both shim internals and the layout of bootparams and
   the x86 setup header. Having this maintenance burden on other architectures
   (which don't need shim in the first place) is hard to justify, so instead,
   we are introducing a generic Linux/UEFI boot protocol.
 
 Summary of changes:
 - Boot time GDT handling changes (Arvind)
 - Simplify handling of EFI properties table on arm64
 - Generic EFI stub cleanups, to improve command line handling, file I/O,
   memory allocation, etc.
 - Introduce a generic initrd loading method based on calling back into
   the firmware, instead of relying on the x86 EFI handover protocol or
   device tree.
 - Introduce a mixed mode boot method that does not rely on the x86 EFI
   handover protocol either, and could potentially be adopted by other
   architectures (if another one ever surfaces where one execution mode
   is a superset of another)
 - Clean up the contents of struct efi, and move out everything that
   doesn't need to be stored there.
 - Incorporate support for UEFI spec v2.8A changes that permit firmware
   implementations to return EFI_UNSUPPORTED from UEFI runtime services at
   OS runtime, and expose a mask of which ones are supported or unsupported
   via a configuration table.
 - Various documentation updates and minor code cleanups (Heinrich)
 - Partial fix for the lack of by-VA cache maintenance in the decompressor
   on 32-bit ARM. Note that these patches were deliberately put at the
   beginning so they can be used as a stable branch that will be shared with
   a PR containing the complete fix, which I will send to the ARM tree.
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Merge tag 'efi-next' of git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi into efi/core

Pull EFI updates for v5.7 from Ard Biesheuvel:

This time, the set of changes for the EFI subsystem is much larger than
usual. The main reasons are:

 - Get things cleaned up before EFI support for RISC-V arrives, which will
   increase the size of the validation matrix, and therefore the threshold to
   making drastic changes,

 - After years of defunct maintainership, the GRUB project has finally started
   to consider changes from the distros regarding UEFI boot, some of which are
   highly specific to the way x86 does UEFI secure boot and measured boot,
   based on knowledge of both shim internals and the layout of bootparams and
   the x86 setup header. Having this maintenance burden on other architectures
   (which don't need shim in the first place) is hard to justify, so instead,
   we are introducing a generic Linux/UEFI boot protocol.

Summary of changes:

 - Boot time GDT handling changes (Arvind)

 - Simplify handling of EFI properties table on arm64

 - Generic EFI stub cleanups, to improve command line handling, file I/O,
   memory allocation, etc.

 - Introduce a generic initrd loading method based on calling back into
   the firmware, instead of relying on the x86 EFI handover protocol or
   device tree.

 - Introduce a mixed mode boot method that does not rely on the x86 EFI
   handover protocol either, and could potentially be adopted by other
   architectures (if another one ever surfaces where one execution mode
   is a superset of another)

 - Clean up the contents of struct efi, and move out everything that
   doesn't need to be stored there.

 - Incorporate support for UEFI spec v2.8A changes that permit firmware
   implementations to return EFI_UNSUPPORTED from UEFI runtime services at
   OS runtime, and expose a mask of which ones are supported or unsupported
   via a configuration table.

 - Various documentation updates and minor code cleanups (Heinrich)

 - Partial fix for the lack of by-VA cache maintenance in the decompressor
   on 32-bit ARM. Note that these patches were deliberately put at the
   beginning so they can be used as a stable branch that will be shared with
   a PR containing the complete fix, which I will send to the ARM tree.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2020-02-26 15:21:22 +01:00
Thomas Gleixner
d364847eed x86/mce/therm_throt: Undo thermal polling properly on CPU offline
Chris Wilson reported splats from running the thermal throttling
workqueue callback on offlined CPUs. The problem is that that callback
should not even run on offlined CPUs but it happens nevertheless because
the offlining callback thermal_throttle_offline() does not symmetrically
undo the setup work done in its onlining counterpart. IOW,

 1. The thermal interrupt vector should be masked out before ...

 2. ... cancelling any pending work synchronously so that no new work is
 enqueued anymore.

Do those things and fix the issue properly.

 [ bp: Write commit message. ]

Fixes: f6656208f0 ("x86/mce/therm_throt: Optimize notifications of thermal throttle")
Reported-by: Chris Wilson <chris@chris-wilson.co.uk>
Tested-by: Pandruvada, Srinivas <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/158120068234.18291.7938335950259651295@skylake-alporthouse-com
2020-02-25 21:21:44 +01:00
Arvind Sankar
6f8f0dc980 x86/vmlinux: Drop unneeded linker script discard of .eh_frame
Now that .eh_frame sections for the files in setup.elf and realmode.elf
are not generated anymore, the linker scripts don't need the special
output section name /DISCARD/ any more.

Remove the one in the main kernel linker script as well, since there are
no .eh_frame sections already, and fix up a comment referencing .eh_frame.

Update the comment in asm/dwarf2.h referring to .eh_frame so it continues
to make sense, as well as being more specific.

 [ bp: Touch up commit message. ]

Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Tested-by: Nathan Chancellor <natechancellor@gmail.com>
Link: https://lkml.kernel.org/r/20200224232129.597160-3-nivedita@alum.mit.edu
2020-02-25 14:51:29 +01:00
Dave Hansen
16171bffc8 x86/pkeys: Add check for pkey "overflow"
Alex Shi reported the pkey macros above arch_set_user_pkey_access()
to be unused.  They are unused, and even refer to a nonexistent
CONFIG option.

But, they might have served a good use, which was to ensure that
the code does not try to set values that would not fit in the
PKRU register.  As it stands, a too-large 'pkey' value would
be likely to silently overflow the u32 new_pkru_bits.

Add a check to look for overflows.  Also add a comment to remind
any future developer to closely examine the types used to store
pkey values if arch_max_pkey() ever changes.

This boots and passes the x86 pkey selftests.

Reported-by: Alex Shi <alex.shi@linux.alibaba.com>
Signed-off-by: Dave Hansen <dave.hansen@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20200122165346.AD4DA150@viggo.jf.intel.com
2020-02-24 20:25:21 +01:00
Ingo Molnar
546121b65f Linux 5.6-rc3
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Merge tag 'v5.6-rc3' into sched/core, to pick up fixes and dependent patches

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2020-02-24 11:36:09 +01:00
Ard Biesheuvel
9a440391b5 x86/ima: Use EFI GetVariable only when available
Replace the EFI runtime services check with one that tells us whether
EFI GetVariable() is implemented by the firmware.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-02-23 21:59:42 +01:00
Ard Biesheuvel
59f2a619a2 efi: Add 'runtime' pointer to struct efi
Instead of going through the EFI system table each time, just copy the
runtime services table pointer into struct efi directly. This is the
last use of the system table pointer in struct efi, allowing us to
drop it in a future patch, along with a fair amount of quirky handling
of the translated address.

Note that usually, the runtime services pointer changes value during
the call to SetVirtualAddressMap(), so grab the updated value as soon
as that call returns. (Mixed mode uses a 1:1 mapping, and kexec boot
enters with the updated address in the system table, so in those cases,
we don't need to do anything here)

Tested-by: Tony Luck <tony.luck@intel.com> # arch/ia64
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-02-23 21:59:42 +01:00
Ard Biesheuvel
9cd437ac0e efi/x86: Make fw_vendor, config_table and runtime sysfs nodes x86 specific
There is some code that exposes physical addresses of certain parts of
the EFI firmware implementation via sysfs nodes. These nodes are only
used on x86, and are of dubious value to begin with, so let's move
their handling into the x86 arch code.

Tested-by: Tony Luck <tony.luck@intel.com> # arch/ia64
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-02-23 21:59:42 +01:00
Ard Biesheuvel
0a67361dcd efi/x86: Remove runtime table address from kexec EFI setup data
Since commit 33b85447fa ("efi/x86: Drop two near identical versions
of efi_runtime_init()"), we no longer map the EFI runtime services table
before calling SetVirtualAddressMap(), which means we don't need the 1:1
mapped physical address of this table, and so there is no point in passing
the address via EFI setup data on kexec boot.

Note that the kexec tools will still look for this address in sysfs, so
we still need to provide it.

Tested-by: Tony Luck <tony.luck@intel.com> # arch/ia64
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-02-23 21:59:42 +01:00
Linus Torvalds
dca132a60f Two fixes for the AMD MCE driver:
- Populate the per CPU MCA bank descriptor pointer only after it has been
     completely set up to prevent a use-after-free in case that one of the
     subsequent initialization step fails
 
   - Implement a proper release function for the sysfs entries of MCA
     threshold controls instead of freeing the memory right in the CPU
     teardown code, which leads to another use-after-free when the
     associated sysfs file is opened and accessed.
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Merge tag 'ras-urgent-2020-02-22' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull RAS fixes from Thomas Gleixner:
 "Two fixes for the AMD MCE driver:

   - Populate the per CPU MCA bank descriptor pointer only after it has
     been completely set up to prevent a use-after-free in case that one
     of the subsequent initialization step fails

   - Implement a proper release function for the sysfs entries of MCA
     threshold controls instead of freeing the memory right in the CPU
     teardown code, which leads to another use-after-free when the
     associated sysfs file is opened and accessed"

* tag 'ras-urgent-2020-02-22' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/mce/amd: Fix kobject lifetime
  x86/mce/amd: Publish the bank pointer only after setup has succeeded
2020-02-22 18:02:10 -08:00
Linus Torvalds
fca1037864 Two fixes for x86:
- Remove the __force_oder definiton from the kaslr boot code as it is
     already defined in the page table code which makes GCC 10 builds fail
     because it changed the default to -fno-common.
 
   - Address the AMD erratum 1054 concerning the IRPERF capability and
     enable the Instructions Retired fixed counter on machines which are not
     affected by the erratum.
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Merge tag 'x86-urgent-2020-02-22' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 fixes from Thomas Gleixner:
 "Two fixes for x86:

   - Remove the __force_oder definiton from the kaslr boot code as it is
     already defined in the page table code which makes GCC 10 builds
     fail because it changed the default to -fno-common.

   - Address the AMD erratum 1054 concerning the IRPERF capability and
     enable the Instructions Retired fixed counter on machines which are
     not affected by the erratum"

* tag 'x86-urgent-2020-02-22' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/cpu/amd: Enable the fixed Instructions Retired counter IRPERF
  x86/boot/compressed: Don't declare __force_order in kaslr_64.c
2020-02-22 17:08:16 -08:00
Arvind Sankar
67a6af7ad1 x86/boot: Remove KEEP_SEGMENTS support
Commit a24e785111 ("i386: paravirt boot sequence") added this flag for
use by paravirtualized environments such as Xen. However, Xen never made
use of this flag [1], and it was only ever used by lguest [2].

Commit ecda85e702 ("x86/lguest: Remove lguest support") removed
lguest, so KEEP_SEGMENTS has lost its last user.

[1] https://lore.kernel.org/lkml/4D4B097C.5050405@goop.org
[2] https://www.mail-archive.com/lguest@lists.ozlabs.org/msg00469.html

Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200202171353.3736319-2-nivedita@alum.mit.edu
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-02-22 23:37:37 +01:00
Peter Zijlstra (Intel)
6650cdd9a8 x86/split_lock: Enable split lock detection by kernel
A split-lock occurs when an atomic instruction operates on data that spans
two cache lines. In order to maintain atomicity the core takes a global bus
lock.

This is typically >1000 cycles slower than an atomic operation within a
cache line. It also disrupts performance on other cores (which must wait
for the bus lock to be released before their memory operations can
complete). For real-time systems this may mean missing deadlines. For other
systems it may just be very annoying.

Some CPUs have the capability to raise an #AC trap when a split lock is
attempted.

Provide a command line option to give the user choices on how to handle
this:

split_lock_detect=
	off	- not enabled (no traps for split locks)
	warn	- warn once when an application does a
		  split lock, but allow it to continue
		  running.
	fatal	- Send SIGBUS to applications that cause split lock

On systems that support split lock detection the default is "warn". Note
that if the kernel hits a split lock in any mode other than "off" it will
OOPs.

One implementation wrinkle is that the MSR to control the split lock
detection is per-core, not per thread. This might result in some short
lived races on HT systems in "warn" mode if Linux tries to enable on one
thread while disabling on the other. Race analysis by Sean Christopherson:

  - Toggling of split-lock is only done in "warn" mode.  Worst case
    scenario of a race is that a misbehaving task will generate multiple
    #AC exceptions on the same instruction.  And this race will only occur
    if both siblings are running tasks that generate split-lock #ACs, e.g.
    a race where sibling threads are writing different values will only
    occur if CPUx is disabling split-lock after an #AC and CPUy is
    re-enabling split-lock after *its* previous task generated an #AC.
  - Transitioning between off/warn/fatal modes at runtime isn't supported
    and disabling is tracked per task, so hardware will always reach a steady
    state that matches the configured mode.  I.e. split-lock is guaranteed to
    be enabled in hardware once all _TIF_SLD threads have been scheduled out.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Co-developed-by: Fenghua Yu <fenghua.yu@intel.com>
Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Co-developed-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lore.kernel.org/r/20200126200535.GB30377@agluck-desk2.amr.corp.intel.com
2020-02-20 21:17:53 +01:00
Kim Phillips
21b5ee59ef x86/cpu/amd: Enable the fixed Instructions Retired counter IRPERF
Commit

  aaf248848d ("perf/x86/msr: Add AMD IRPERF (Instructions Retired)
		  performance counter")

added support for access to the free-running counter via 'perf -e
msr/irperf/', but when exercised, it always returns a 0 count:

BEFORE:

  $ perf stat -e instructions,msr/irperf/ true

   Performance counter stats for 'true':

             624,833      instructions
                   0      msr/irperf/

Simply set its enable bit - HWCR bit 30 - to make it start counting.

Enablement is restricted to all machines advertising IRPERF capability,
except those susceptible to an erratum that makes the IRPERF return
bad values.

That erratum occurs in Family 17h models 00-1fh [1], but not in F17h
models 20h and above [2].

AFTER (on a family 17h model 31h machine):

  $ perf stat -e instructions,msr/irperf/ true

   Performance counter stats for 'true':

             621,690      instructions
             622,490      msr/irperf/

[1] Revision Guide for AMD Family 17h Models 00h-0Fh Processors
[2] Revision Guide for AMD Family 17h Models 30h-3Fh Processors

The revision guides are available from the bugzilla Link below.

 [ bp: Massage commit message. ]

Fixes: aaf248848d ("perf/x86/msr: Add AMD IRPERF (Instructions Retired) performance counter")
Signed-off-by: Kim Phillips <kim.phillips@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: stable@vger.kernel.org
Link: https://bugzilla.kernel.org/show_bug.cgi?id=206537
Link: http://lkml.kernel.org/r/20200214201805.13830-1-kim.phillips@amd.com
2020-02-19 20:01:54 +01:00
Prarit Bhargava
2976908e41 x86/mce: Do not log spurious corrected mce errors
A user has reported that they are seeing spurious corrected errors on
their hardware.

Intel Errata HSD131, HSM142, HSW131, and BDM48 report that "spurious
corrected errors may be logged in the IA32_MC0_STATUS register with
the valid field (bit 63) set, the uncorrected error field (bit 61) not
set, a Model Specific Error Code (bits [31:16]) of 0x000F, and an MCA
Error Code (bits [15:0]) of 0x0005." The Errata PDFs are linked in the
bugzilla below.

Block these spurious errors from the console and logs.

 [ bp: Move the intel_filter_mce() header declarations into the already
   existing CONFIG_X86_MCE_INTEL ifdeffery. ]

Co-developed-by: Alexander Krupp <centos@akr.yagii.de>
Signed-off-by: Alexander Krupp <centos@akr.yagii.de>
Signed-off-by: Prarit Bhargava <prarit@redhat.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://bugzilla.kernel.org/show_bug.cgi?id=206587
Link: https://lkml.kernel.org/r/20200219131611.36816-1-prarit@redhat.com
2020-02-19 18:14:49 +01:00
Benjamin Thiel
b10c307f6f x86/cpu: Move prototype for get_umwait_control_msr() to a global location
.. in order to fix a -Wmissing-prototypes warning.

No functional change.

Signed-off-by: Benjamin Thiel <b.thiel@posteo.de>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: kvm@vger.kernel.org
Link: https://lkml.kernel.org/r/20200123172945.7235-1-b.thiel@posteo.de
2020-02-17 19:32:45 +01:00
Benjamin Thiel
cdcb58cc05 x86/iopl: Include prototype header for ksys_ioperm()
.. in order to fix a -Wmissing-prototype warning.

No functional change.

Signed-off-by: Benjamin Thiel <b.thiel@posteo.de>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20200123133051.5974-1-b.thiel@posteo.de
2020-02-17 16:36:53 +01:00
Thomas Gleixner
b95a8a27c3 x86/vdso: Use generic VDSO clock mode storage
Switch to the generic VDSO clock mode storage.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Vincenzo Frascino <vincenzo.frascino@arm.com> (VDSO parts)
Acked-by: Juergen Gross <jgross@suse.com> (Xen parts)
Acked-by: Paolo Bonzini <pbonzini@redhat.com> (KVM parts)
Link: https://lkml.kernel.org/r/20200207124403.152039903@linutronix.de
2020-02-17 14:40:23 +01:00
Thomas Gleixner
eec399dd86 x86/vdso: Move VDSO clocksource state tracking to callback
All architectures which use the generic VDSO code have their own storage
for the VDSO clock mode. That's pointless and just requires duplicate code.

X86 abuses the function which retrieves the architecture specific clock
mode storage to mark the clocksource as used in the VDSO. That's silly
because this is invoked on every tick when the VDSO data is updated.

Move this functionality to the clocksource::enable() callback so it gets
invoked once when the clocksource is installed. This allows to make the
clock mode storage generic.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Michael Kelley <mikelley@microsoft.com>  (Hyper-V parts)
Reviewed-by: Vincenzo Frascino <vincenzo.frascino@arm.com> (VDSO parts)
Acked-by: Juergen Gross <jgross@suse.com> (Xen parts)
Link: https://lkml.kernel.org/r/20200207124402.934519777@linutronix.de
2020-02-17 14:40:22 +01:00
Martin Molnar
4d1d0977a2 x86: Fix a handful of typos
Fix a couple of typos in code comments.

 [ bp: While at it: s/IRQ's/IRQs/. ]

Signed-off-by: Martin Molnar <martin.molnar.programming@gmail.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Randy Dunlap <rdunlap@infradead.org>
Link: https://lkml.kernel.org/r/0819a044-c360-44a4-f0b6-3f5bafe2d35c@gmail.com
2020-02-16 20:58:06 +01:00
Al Viro
c8e3dd8660 x86 user stack frame reads: switch to explicit __get_user()
rather than relying upon the magic in raw_copy_from_user()

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-02-15 17:26:26 -05:00
Thomas Gleixner
51dede9c05 x86/mce/amd: Fix kobject lifetime
Accessing the MCA thresholding controls in sysfs concurrently with CPU
hotplug can lead to a couple of KASAN-reported issues:

  BUG: KASAN: use-after-free in sysfs_file_ops+0x155/0x180
  Read of size 8 at addr ffff888367578940 by task grep/4019

and

  BUG: KASAN: use-after-free in show_error_count+0x15c/0x180
  Read of size 2 at addr ffff888368a05514 by task grep/4454

for example. Both result from the fact that the threshold block
creation/teardown code frees the descriptor memory itself instead of
defining proper ->release function and leaving it to the driver core to
take care of that, after all sysfs accesses have completed.

Do that and get rid of the custom freeing code, fixing the above UAFs in
the process.

  [ bp: write commit message. ]

Fixes: 9526866439 ("[PATCH] x86_64: mce_amd support for family 0x10 processors")
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: <stable@vger.kernel.org>
Link: https://lkml.kernel.org/r/20200214082801.13836-1-bp@alien8.de
2020-02-14 09:28:31 +01:00
Borislav Petkov
6e5cf31fbe x86/mce/amd: Publish the bank pointer only after setup has succeeded
threshold_create_bank() creates a bank descriptor per MCA error
thresholding counter which can be controlled over sysfs. It publishes
the pointer to that bank in a per-CPU variable and then goes on to
create additional thresholding blocks if the bank has such.

However, that creation of additional blocks in
allocate_threshold_blocks() can fail, leading to a use-after-free
through the per-CPU pointer.

Therefore, publish that pointer only after all blocks have been setup
successfully.

Fixes: 019f34fccf ("x86, MCE, AMD: Move shared bank to node descriptor")
Reported-by: Saar Amar <Saar.Amar@microsoft.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: <stable@vger.kernel.org>
Link: http://lkml.kernel.org/r/20200128140846.phctkvx5btiexvbx@kili.mountain
2020-02-13 18:58:39 +01:00
Yu-cheng Yu
e70b100806 x86/fpu/xstate: Warn when checking alignment of disabled xfeatures
An XSAVES component's alignment/offset is meaningful only when the
feature is enabled. Return zero and WARN_ONCE on checking alignment of
disabled features.

Signed-off-by: Yu-cheng Yu <yu-cheng.yu@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Dave Hansen <dave.hansen@linux.intel.com>
Link: https://lkml.kernel.org/r/20200109211452.27369-4-yu-cheng.yu@intel.com
2020-02-12 15:43:34 +01:00
Yu-cheng Yu
49a91d61ae x86/fpu/xstate: Fix XSAVES offsets in setup_xstate_comp()
In setup_xstate_comp(), each XSAVES component offset starts from the
end of its preceding component plus alignment. A disabled feature does
not take space and its offset should be set to the end of its preceding
one with no alignment. However, in this case, alignment is incorrectly
added to the offset, which can cause the next component to have a wrong
offset.

This problem has not been visible because currently there is no xfeature
requiring alignment.

Fix it by tracking the next starting offset only from enabled
xfeatures. To make it clear, also change the function name to
setup_xstate_comp_offsets().

 [ bp: Fix a typo in the comment above it, while at it. ]

Signed-off-by: Yu-cheng Yu <yu-cheng.yu@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Dave Hansen <dave.hansen@linux.intel.com>
Link: https://lkml.kernel.org/r/20200109211452.27369-3-yu-cheng.yu@intel.com
2020-02-12 15:43:31 +01:00
Ard Biesheuvel
ff5ac61ee8 x86/ima: use correct identifier for SetupMode variable
The IMA arch code attempts to inspect the "SetupMode" EFI variable
by populating a variable called efi_SetupMode_name with the string
"SecureBoot" and passing that to the EFI GetVariable service, which
obviously does not yield the expected result.

Given that the string is only referenced a single time, let's get
rid of the intermediate variable, and pass the correct string as
an immediate argument. While at it, do the same for "SecureBoot".

Fixes: 399574c64e ("x86/ima: retry detecting secure boot mode")
Fixes: 980ef4d22a ("x86/ima: check EFI SetupMode too")
Cc: Matthew Garrett <mjg59@google.com>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Cc: stable@vger.kernel.org # v5.3
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-02-11 14:42:37 -05:00
Yu-cheng Yu
c12e13dcd8 x86/fpu/xstate: Fix last_good_offset in setup_xstate_features()
The function setup_xstate_features() uses CPUID to find each xfeature's
standard-format offset and size.  Since XSAVES always uses the compacted
format, supervisor xstates are *NEVER* in the standard-format and their
offsets are left as -1's.  However, they are still being tracked as
last_good_offset.

Fix it by tracking only user xstate offsets.

 [ bp: Use xfeature_is_supervisor() and save an indentation level. Drop
   now unused xfeature_is_user(). ]

Signed-off-by: Yu-cheng Yu <yu-cheng.yu@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Dave Hansen <dave.hansen@linux.intel.com>
Link: https://lkml.kernel.org/r/20200109211452.27369-2-yu-cheng.yu@intel.com
2020-02-11 19:54:04 +01:00
Linus Torvalds
1a2a76c268 A set of fixes for X86:
- Ensure that the PIT is set up when the local APIC is disable or
    configured in legacy mode. This is caused by an ordering issue
    introduced in the recent changes which skip PIT initialization when the
    TSC and APIC frequencies are already known.
 
  - Handle malformed SRAT tables during early ACPI parsing which caused an
    infinite loop anda boot hang.
 
  - Fix a long standing race in the affinity setting code which affects PCI
    devices with non-maskable MSI interrupts. The problem is caused by the
    non-atomic writes of the MSI address (destination APIC id) and data
    (vector) fields which the device uses to construct the MSI message. The
    non-atomic writes are mandated by PCI.
 
    If both fields change and the device raises an interrupt after writing
    address and before writing data, then the MSI block constructs a
    inconsistent message which causes interrupts to be lost and subsequent
    malfunction of the device.
 
    The fix is to redirect the interrupt to the new vector on the current
    CPU first and then switch it over to the new target CPU. This allows to
    observe an eventually raised interrupt in the transitional stage (old
    CPU, new vector) to be observed in the APIC IRR and retriggered on the
    new target CPU and the new vector. The potential spurious interrupts
    caused by this are harmless and can in the worst case expose a buggy
    driver (all handlers have to be able to deal with spurious interrupts as
    they can and do happen for various reasons).
 
  - Add the missing suspend/resume mechanism for the HYPERV hypercall page
    which prevents resume hibernation on HYPERV guests. This change got
    lost before the merge window.
 
  - Mask the IOAPIC before disabling the local APIC to prevent potentially
    stale IOAPIC remote IRR bits which cause stale interrupt lines after
    resume.
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Merge tag 'x86-urgent-2020-02-09' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 fixes from Thomas Gleixner:
 "A set of fixes for X86:

   - Ensure that the PIT is set up when the local APIC is disable or
     configured in legacy mode. This is caused by an ordering issue
     introduced in the recent changes which skip PIT initialization when
     the TSC and APIC frequencies are already known.

   - Handle malformed SRAT tables during early ACPI parsing which caused
     an infinite loop anda boot hang.

   - Fix a long standing race in the affinity setting code which affects
     PCI devices with non-maskable MSI interrupts. The problem is caused
     by the non-atomic writes of the MSI address (destination APIC id)
     and data (vector) fields which the device uses to construct the MSI
     message. The non-atomic writes are mandated by PCI.

     If both fields change and the device raises an interrupt after
     writing address and before writing data, then the MSI block
     constructs a inconsistent message which causes interrupts to be
     lost and subsequent malfunction of the device.

     The fix is to redirect the interrupt to the new vector on the
     current CPU first and then switch it over to the new target CPU.
     This allows to observe an eventually raised interrupt in the
     transitional stage (old CPU, new vector) to be observed in the APIC
     IRR and retriggered on the new target CPU and the new vector.

     The potential spurious interrupts caused by this are harmless and
     can in the worst case expose a buggy driver (all handlers have to
     be able to deal with spurious interrupts as they can and do happen
     for various reasons).

   - Add the missing suspend/resume mechanism for the HYPERV hypercall
     page which prevents resume hibernation on HYPERV guests. This
     change got lost before the merge window.

   - Mask the IOAPIC before disabling the local APIC to prevent
     potentially stale IOAPIC remote IRR bits which cause stale
     interrupt lines after resume"

* tag 'x86-urgent-2020-02-09' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/apic: Mask IOAPIC entries when disabling the local APIC
  x86/hyperv: Suspend/resume the hypercall page for hibernation
  x86/apic/msi: Plug non-maskable MSI affinity race
  x86/boot: Handle malformed SRAT tables during early ACPI parsing
  x86/timer: Don't skip PIT setup when APIC is disabled or in legacy mode
2020-02-09 12:11:12 -08:00
Linus Torvalds
c9d35ee049 Merge branch 'merge.nfs-fs_parse.1' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs file system parameter updates from Al Viro:
 "Saner fs_parser.c guts and data structures. The system-wide registry
  of syntax types (string/enum/int32/oct32/.../etc.) is gone and so is
  the horror switch() in fs_parse() that would have to grow another case
  every time something got added to that system-wide registry.

  New syntax types can be added by filesystems easily now, and their
  namespace is that of functions - not of system-wide enum members. IOW,
  they can be shared or kept private and if some turn out to be widely
  useful, we can make them common library helpers, etc., without having
  to do anything whatsoever to fs_parse() itself.

  And we already get that kind of requests - the thing that finally
  pushed me into doing that was "oh, and let's add one for timeouts -
  things like 15s or 2h". If some filesystem really wants that, let them
  do it. Without somebody having to play gatekeeper for the variants
  blessed by direct support in fs_parse(), TYVM.

  Quite a bit of boilerplate is gone. And IMO the data structures make a
  lot more sense now. -200LoC, while we are at it"

* 'merge.nfs-fs_parse.1' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (25 commits)
  tmpfs: switch to use of invalfc()
  cgroup1: switch to use of errorfc() et.al.
  procfs: switch to use of invalfc()
  hugetlbfs: switch to use of invalfc()
  cramfs: switch to use of errofc() et.al.
  gfs2: switch to use of errorfc() et.al.
  fuse: switch to use errorfc() et.al.
  ceph: use errorfc() and friends instead of spelling the prefix out
  prefix-handling analogues of errorf() and friends
  turn fs_param_is_... into functions
  fs_parse: handle optional arguments sanely
  fs_parse: fold fs_parameter_desc/fs_parameter_spec
  fs_parser: remove fs_parameter_description name field
  add prefix to fs_context->log
  ceph_parse_param(), ceph_parse_mon_ips(): switch to passing fc_log
  new primitive: __fs_parse()
  switch rbd and libceph to p_log-based primitives
  struct p_log, variants of warnf() et.al. taking that one instead
  teach logfc() to handle prefices, give it saner calling conventions
  get rid of cg_invalf()
  ...
2020-02-08 13:26:41 -08:00
Al Viro
d7167b1499 fs_parse: fold fs_parameter_desc/fs_parameter_spec
The former contains nothing but a pointer to an array of the latter...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-02-07 14:48:37 -05:00
Eric Sandeen
96cafb9ccb fs_parser: remove fs_parameter_description name field
Unused now.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-02-07 14:48:36 -05:00
Tony W Wang-oc
0f378d73d4 x86/apic: Mask IOAPIC entries when disabling the local APIC
When a system suspends, the local APIC is disabled in the suspend sequence,
but the IOAPIC is left in the current state. This means unmasked interrupt
lines stay unmasked. This is usually the case for IOAPIC pin 9 to which the
ACPI interrupt is connected.

That means that in suspended state the IOAPIC can respond to an external
interrupt, e.g. the wakeup via keyboard/RTC/ACPI, but the interrupt message
cannot be handled by the disabled local APIC. As a consequence the Remote
IRR bit is set, but the local APIC does not send an EOI to acknowledge
it. This causes the affected interrupt line to become stale and the stale
Remote IRR bit will cause a hang when __synchronize_hardirq() is invoked
for that interrupt line.

To prevent this, mask all IOAPIC entries before disabling the local
APIC. The resume code already has the unmask operation inside.

[ tglx: Massaged changelog ]

Signed-off-by: Tony W Wang-oc <TonyWWang-oc@zhaoxin.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/1579076539-7267-1-git-send-email-TonyWWang-oc@zhaoxin.com
2020-02-07 15:32:16 +01:00
Linus Torvalds
90568ecf56 s390:
* fix register corruption
 * ENOTSUPP/EOPNOTSUPP mixed
 * reset cleanups/fixes
 * selftests
 
 x86:
 * Bug fixes and cleanups
 * AMD support for APIC virtualization even in combination with
   in-kernel PIT or IOAPIC.
 
 MIPS:
 * Compilation fix.
 
 Generic:
 * Fix refcount overflow for zero page.
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Merge tag 'kvm-5.6-2' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull more KVM updates from Paolo Bonzini:
 "s390:
   - fix register corruption
   - ENOTSUPP/EOPNOTSUPP mixed
   - reset cleanups/fixes
   - selftests

  x86:
   - Bug fixes and cleanups
   - AMD support for APIC virtualization even in combination with
     in-kernel PIT or IOAPIC.

  MIPS:
   - Compilation fix.

  Generic:
   - Fix refcount overflow for zero page"

* tag 'kvm-5.6-2' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (42 commits)
  KVM: vmx: delete meaningless vmx_decache_cr0_guest_bits() declaration
  KVM: x86: Mark CR4.UMIP as reserved based on associated CPUID bit
  x86: vmxfeatures: rename features for consistency with KVM and manual
  KVM: SVM: relax conditions for allowing MSR_IA32_SPEC_CTRL accesses
  KVM: x86: Fix perfctr WRMSR for running counters
  x86/kvm/hyper-v: don't allow to turn on unsupported VMX controls for nested guests
  x86/kvm/hyper-v: move VMX controls sanitization out of nested_enable_evmcs()
  kvm: mmu: Separate generating and setting mmio ptes
  kvm: mmu: Replace unsigned with unsigned int for PTE access
  KVM: nVMX: Remove stale comment from nested_vmx_load_cr3()
  KVM: MIPS: Fold comparecount_func() into comparecount_wakeup()
  KVM: MIPS: Fix a build error due to referencing not-yet-defined function
  x86/kvm: do not setup pv tlb flush when not paravirtualized
  KVM: fix overflow of zero page refcount with ksm running
  KVM: x86: Take a u64 when checking for a valid dr7 value
  KVM: x86: use raw clock values consistently
  KVM: x86: reorganize pvclock_gtod_data members
  KVM: nVMX: delete meaningless nested_vmx_run() declaration
  KVM: SVM: allow AVIC without split irqchip
  kvm: ioapic: Lazy update IOAPIC EOI
  ...
2020-02-06 09:07:45 -08:00
Thadeu Lima de Souza Cascardo
64b38bd190 x86/kvm: do not setup pv tlb flush when not paravirtualized
kvm_setup_pv_tlb_flush will waste memory and print a misguiding message
when KVM paravirtualization is not available.

Intel SDM says that the when cpuid is used with EAX higher than the
maximum supported value for basic of extended function, the data for the
highest supported basic function will be returned.

So, in some systems, kvm_arch_para_features will return bogus data,
causing kvm_setup_pv_tlb_flush to detect support for pv tlb flush.

Testing for kvm_para_available will work as it checks for the hypervisor
signature.

Besides, when the "nopv" command line parameter is used, it should not
continue as well, as kvm_guest_init will no be called in that case.

Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-02-05 15:28:07 +01:00
Alexey Dobriyan
97a32539b9 proc: convert everything to "struct proc_ops"
The most notable change is DEFINE_SHOW_ATTRIBUTE macro split in
seq_file.h.

Conversion rule is:

	llseek		=> proc_lseek
	unlocked_ioctl	=> proc_ioctl

	xxx		=> proc_xxx

	delete ".owner = THIS_MODULE" line

[akpm@linux-foundation.org: fix drivers/isdn/capi/kcapi_proc.c]
[sfr@canb.auug.org.au: fix kernel/sched/psi.c]
  Link: http://lkml.kernel.org/r/20200122180545.36222f50@canb.auug.org.au
Link: http://lkml.kernel.org/r/20191225172546.GB13378@avx2
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-02-04 03:05:26 +00:00
Thomas Gleixner
6f1a4891a5 x86/apic/msi: Plug non-maskable MSI affinity race
Evan tracked down a subtle race between the update of the MSI message and
the device raising an interrupt internally on PCI devices which do not
support MSI masking. The update of the MSI message is non-atomic and
consists of either 2 or 3 sequential 32bit wide writes to the PCI config
space.

   - Write address low 32bits
   - Write address high 32bits (If supported by device)
   - Write data

When an interrupt is migrated then both address and data might change, so
the kernel attempts to mask the MSI interrupt first. But for MSI masking is
optional, so there exist devices which do not provide it. That means that
if the device raises an interrupt internally between the writes then a MSI
message is sent built from half updated state.

On x86 this can lead to spurious interrupts on the wrong interrupt
vector when the affinity setting changes both address and data. As a
consequence the device interrupt can be lost causing the device to
become stuck or malfunctioning.

Evan tried to handle that by disabling MSI accross an MSI message
update. That's not feasible because disabling MSI has issues on its own:

 If MSI is disabled the PCI device is routing an interrupt to the legacy
 INTx mechanism. The INTx delivery can be disabled, but the disablement is
 not working on all devices.

 Some devices lose interrupts when both MSI and INTx delivery are disabled.

Another way to solve this would be to enforce the allocation of the same
vector on all CPUs in the system for this kind of screwed devices. That
could be done, but it would bring back the vector space exhaustion problems
which got solved a few years ago.

Fortunately the high address (if supported by the device) is only relevant
when X2APIC is enabled which implies interrupt remapping. In the interrupt
remapping case the affinity setting is happening at the interrupt remapping
unit and the PCI MSI message is programmed only once when the PCI device is
initialized.

That makes it possible to solve it with a two step update:

  1) Target the MSI msg to the new vector on the current target CPU

  2) Target the MSI msg to the new vector on the new target CPU

In both cases writing the MSI message is only changing a single 32bit word
which prevents the issue of inconsistency.

After writing the final destination it is necessary to check whether the
device issued an interrupt while the intermediate state #1 (new vector,
current CPU) was in effect.

This is possible because the affinity change is always happening on the
current target CPU. The code runs with interrupts disabled, so the
interrupt can be detected by checking the IRR of the local APIC. If the
vector is pending in the IRR then the interrupt is retriggered on the new
target CPU by sending an IPI for the associated vector on the target CPU.

This can cause spurious interrupts on both the local and the new target
CPU.

 1) If the new vector is not in use on the local CPU and the device
    affected by the affinity change raised an interrupt during the
    transitional state (step #1 above) then interrupt entry code will
    ignore that spurious interrupt. The vector is marked so that the
    'No irq handler for vector' warning is supressed once.

 2) If the new vector is in use already on the local CPU then the IRR check
    might see an pending interrupt from the device which is using this
    vector. The IPI to the new target CPU will then invoke the handler of
    the device, which got the affinity change, even if that device did not
    issue an interrupt

 3) If the new vector is in use already on the local CPU and the device
    affected by the affinity change raised an interrupt during the
    transitional state (step #1 above) then the handler of the device which
    uses that vector on the local CPU will be invoked.

expose issues in device driver interrupt handlers which are not prepared to
handle a spurious interrupt correctly. This not a regression, it's just
exposing something which was already broken as spurious interrupts can
happen for a lot of reasons and all driver handlers need to be able to deal
with them.

Reported-by: Evan Green <evgreen@chromium.org>
Debugged-by: Evan Green <evgreen@chromium.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Evan Green <evgreen@chromium.org>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/87imkr4s7n.fsf@nanos.tec.linutronix.de
2020-02-01 09:31:47 +01:00
Linus Torvalds
b70a2d6b29 Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Ingo Molnar:
 "Misc fixes:

   - three fixes and a cleanup for the resctrl code

   - a HyperV fix

   - a fix to /proc/kcore contents in live debugging sessions

   - a fix for the x86 decoder opcode map"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/decoder: Add TEST opcode to Group3-2
  x86/resctrl: Clean up unused function parameter in mkdir path
  x86/resctrl: Fix a deadlock due to inaccurate reference
  x86/resctrl: Fix use-after-free due to inaccurate refcount of rdtgroup
  x86/resctrl: Fix use-after-free when deleting resource groups
  x86/hyper-v: Add "polling" bit to hv_synic_sint
  x86/crash: Define arch_crash_save_vmcoreinfo() if CONFIG_CRASH_CORE=y
2020-01-31 11:05:33 -08:00
Linus Torvalds
ccaaaf6fe5 MPX requires recompiling applications, which requires compiler support.
Unfortunately, GCC 9.1 is expected to be be released without support for
 MPX.  This means that there was only a relatively small window where
 folks could have ever used MPX.  It failed to gain wide adoption in the
 industry, and Linux was the only mainstream OS to ever support it widely.
 
 Support for the feature may also disappear on future processors.
 
 This set completes the process that we started during the 5.4 merge window.
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Merge tag 'mpx-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/daveh/x86-mpx

Pull x86 MPX removal from Dave Hansen:
 "MPX requires recompiling applications, which requires compiler
  support. Unfortunately, GCC 9.1 is expected to be be released without
  support for MPX. This means that there was only a relatively small
  window where folks could have ever used MPX. It failed to gain wide
  adoption in the industry, and Linux was the only mainstream OS to ever
  support it widely.

  Support for the feature may also disappear on future processors.

  This set completes the process that we started during the 5.4 merge
  window when the MPX prctl()s were removed. XSAVE support is left in
  place, which allows MPX-using KVM guests to continue to function"

* tag 'mpx-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/daveh/x86-mpx:
  x86/mpx: remove MPX from arch/x86
  mm: remove arch_bprm_mm_init() hook
  x86/mpx: remove bounds exception code
  x86/mpx: remove build infrastructure
  x86/alternatives: add missing insn.h include
2020-01-30 16:11:50 -08:00
Linus Torvalds
ca9b5b6283 TTY/Serial driver updates for 5.6-rc1
Here are the big set of tty and serial driver updates for 5.6-rc1
 
 Included in here are:
 	- dummy_con cleanups (touches lots of arch code)
 	- sysrq logic cleanups (touches lots of serial drivers)
 	- samsung driver fixes (wasn't really being built)
 	- conmakeshash move to tty subdir out of scripts
 	- lots of small tty/serial driver updates
 
 All of these have been in linux-next for a while with no reported
 issues.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'tty-5.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

Pull tty/serial driver updates from Greg KH:
 "Here are the big set of tty and serial driver updates for 5.6-rc1

  Included in here are:
   - dummy_con cleanups (touches lots of arch code)
   - sysrq logic cleanups (touches lots of serial drivers)
   - samsung driver fixes (wasn't really being built)
   - conmakeshash move to tty subdir out of scripts
   - lots of small tty/serial driver updates

  All of these have been in linux-next for a while with no reported
  issues"

* tag 'tty-5.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (140 commits)
  tty: n_hdlc: Use flexible-array member and struct_size() helper
  tty: baudrate: SPARC supports few more baud rates
  tty: baudrate: Synchronise baud_table[] and baud_bits[]
  tty: serial: meson_uart: Add support for kernel debugger
  serial: imx: fix a race condition in receive path
  serial: 8250_bcm2835aux: Document struct bcm2835aux_data
  serial: 8250_bcm2835aux: Use generic remapping code
  serial: 8250_bcm2835aux: Allocate uart_8250_port on stack
  serial: 8250_bcm2835aux: Suppress register_port error on -EPROBE_DEFER
  serial: 8250_bcm2835aux: Suppress clk_get error on -EPROBE_DEFER
  serial: 8250_bcm2835aux: Fix line mismatch on driver unbind
  serial_core: Remove unused member in uart_port
  vt: Correct comment documenting do_take_over_console()
  vt: Delete comment referencing non-existent unbind_con_driver()
  arch/xtensa/setup: Drop dummy_con initialization
  arch/x86/setup: Drop dummy_con initialization
  arch/unicore32/setup: Drop dummy_con initialization
  arch/sparc/setup: Drop dummy_con initialization
  arch/sh/setup: Drop dummy_con initialization
  arch/s390/setup: Drop dummy_con initialization
  ...
2020-01-29 10:13:27 -08:00
Thomas Gleixner
979923871f x86/timer: Don't skip PIT setup when APIC is disabled or in legacy mode
Tony reported a boot regression caused by the recent workaround for systems
which have a disabled (clock gate off) PIT.

On his machine the kernel fails to initialize the PIT because
apic_needs_pit() does not take into account whether the local APIC
interrupt delivery mode will actually allow to setup and use the local
APIC timer. This should be easy to reproduce with acpi=off on the
command line which also disables HPET.

Due to the way the PIT/HPET and APIC setup ordering works (APIC setup can
require working PIT/HPET) the information is not available at the point
where apic_needs_pit() makes this decision.

To address this, split out the interrupt mode selection from
apic_intr_mode_init(), invoke the selection before making the decision
whether PIT is required or not, and add the missing checks into
apic_needs_pit().

Fixes: c8c4076723 ("x86/timer: Skip PIT initialization on modern chipsets")
Reported-by: Anthony Buckley <tony.buckley000@gmail.com>
Tested-by: Anthony Buckley <tony.buckley000@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Daniel Drake <drake@endlessm.com>
Link: https://bugzilla.kernel.org/show_bug.cgi?id=206125
Link: https://lore.kernel.org/r/87sgk6tmk2.fsf@nanos.tec.linutronix.de
2020-01-29 12:50:12 +01:00
Linus Torvalds
511fdb7844 Merge branch 'x86-mtrr-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 mtrr updates from Ingo Molnar:
 "Two changes: restrict /proc/mtrr to CAP_SYS_ADMIN, plus a cleanup"

* 'x86-mtrr-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/mtrr: Require CAP_SYS_ADMIN for all access
  x86/mtrr: Get rid of mtrr_seq_show() forward declaration
2020-01-28 13:06:05 -08:00
Linus Torvalds
4d6245ce8c Merge branch 'x86-fpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 FPU updates from Ingo Molnar:
 "Three changes: fix a race that can result in FPU corruption, plus two
  cleanups"

* 'x86-fpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/fpu: Deactivate FPU state after failure during state load
  x86/fpu/xstate: Make xfeature_is_supervisor()/xfeature_is_user() return bool
  x86/fpu/xstate: Fix small issues
2020-01-28 13:04:38 -08:00