Commit graph

2959 commits

Author SHA1 Message Date
Mark Brown
0de674afe8 arm64: stacktrace: Move export for save_stack_trace_tsk()
Due to refactoring way back in bb53c820c5 ("arm64: stacktrace: avoid
listing stacktrace functions in stacktrace") the EXPORT_SYMBOL_GPL() for
save_stack_trace_tsk() is at the end of __save_stack_trace() rather than
the function it exports. Move it to the expected location.

Signed-off-by: Mark Brown <broonie@kernel.org>
Acked-by: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20200710182402.50473-1-broonie@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2020-07-14 19:16:25 +01:00
Ard Biesheuvel
325f5585ec arm64/acpi: disallow writeable AML opregion mapping for EFI code regions
Given that the contents of EFI runtime code and data regions are
provided by the firmware, as well as the DSDT, it is not unimaginable
that AML code exists today that accesses EFI runtime code regions using
a SystemMemory OpRegion. There is nothing fundamentally wrong with that,
but since we take great care to ensure that executable code is never
mapped writeable and executable at the same time, we should not permit
AML to create writable mapping.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Acked-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Link: https://lore.kernel.org/r/20200626155832.2323789-3-ardb@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2020-07-14 18:02:04 +01:00
Ard Biesheuvel
1583052d11 arm64/acpi: disallow AML memory opregions to access kernel memory
AML uses SystemMemory opregions to allow AML handlers to access MMIO
registers of, e.g., GPIO controllers, or access reserved regions of
memory that are owned by the firmware.

Currently, we also allow AML access to memory that is owned by the
kernel and mapped via the linear region, which does not seem to be
supported by a valid use case, and exposes the kernel's internal
state to AML methods that may be buggy and exploitable.

On arm64, ACPI support requires booting in EFI mode, and so we can cross
reference the requested region against the EFI memory map, rather than
just do a minimal check on the first page. So let's only permit regions
to be remapped by the ACPI core if
- they don't appear in the EFI memory map at all (which is the case for
  most MMIO), or
- they are covered by a single region in the EFI memory map, which is not
  of a type that describes memory that is given to the kernel at boot.

Reported-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Acked-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Link: https://lore.kernel.org/r/20200626155832.2323789-2-ardb@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2020-07-14 18:02:03 +01:00
Linus Torvalds
f4c8824cbc arm64 fixes for -rc5
- Fix workaround for CPU erratum #1418040 to disable the compat vDSO
 
 - Fix OOPs when single-stepping with KGDB
 
 - Fix memory attributes for hypervisor device mappings at EL2
 
 - Fix memory leak in PSCI and remove useless variable assignment
 
 - Fix up some comments and asm labels in our entry code
 
 - Fix broken register table formatting in our generated html docs
 
 - Fix missing NULL sentinel in CPU errata workaround list
 
 - Fix patching of branches in alternative instruction sections
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Merge tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux

Pull arm64 fixes from Will Deacon:
 "An unfortunately large collection of arm64 fixes for -rc5.

  Some of this is absolutely trivial, but the alternatives, vDSO and CPU
  errata workaround fixes are significant. At least people are finding
  and fixing these things, I suppose.

   - Fix workaround for CPU erratum #1418040 to disable the compat vDSO

   - Fix Oops when single-stepping with KGDB

   - Fix memory attributes for hypervisor device mappings at EL2

   - Fix memory leak in PSCI and remove useless variable assignment

   - Fix up some comments and asm labels in our entry code

   - Fix broken register table formatting in our generated html docs

   - Fix missing NULL sentinel in CPU errata workaround list

   - Fix patching of branches in alternative instruction sections"

* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
  arm64/alternatives: don't patch up internal branches
  arm64: Add missing sentinel to erratum_1463225
  arm64: Documentation: Fix broken table in generated HTML
  arm64: kgdb: Fix single-step exception handling oops
  arm64: entry: Tidy up block comments and label numbers
  arm64: Rework ARM_ERRATUM_1414080 handling
  arm64: arch_timer: Disable the compat vdso for cores affected by ARM64_WORKAROUND_1418040
  arm64: arch_timer: Allow an workaround descriptor to disable compat vdso
  arm64: Introduce a way to disable the 32bit vdso
  arm64: entry: Fix the typo in the comment of el1_dbg()
  drivers/firmware/psci: Assign @err directly in hotplug_tests()
  drivers/firmware/psci: Fix memory leakage in alloc_init_cpu_groups()
  KVM: arm64: Fix definition of PAGE_HYP_DEVICE
2020-07-10 08:42:17 -07:00
Ard Biesheuvel
5679b28142 arm64/alternatives: don't patch up internal branches
Commit f7b93d4294 ("arm64/alternatives: use subsections for replacement
sequences") moved the alternatives replacement sequences into subsections,
in order to keep the as close as possible to the code that they replace.

Unfortunately, this broke the logic in branch_insn_requires_update,
which assumed that any branch into kernel executable code was a branch
that required updating, which is no longer the case now that the code
sequences that are patched in are in the same section as the patch site
itself.

So the only way to discriminate branches that require updating and ones
that don't is to check whether the branch targets the replacement sequence
itself, and so we can drop the call to kernel_text_address() entirely.

Fixes: f7b93d4294 ("arm64/alternatives: use subsections for replacement sequences")
Reported-by: Alexandru Elisei <alexandru.elisei@arm.com>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Tested-by: Alexandru Elisei <alexandru.elisei@arm.com>
Link: https://lore.kernel.org/r/20200709125953.30918-1-ardb@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
2020-07-09 14:57:59 +01:00
Florian Fainelli
09c717c92b arm64: Add missing sentinel to erratum_1463225
When the erratum_1463225 array was introduced a sentinel at the end was
missing thus causing a KASAN: global-out-of-bounds in
is_affected_midr_range_list on arm64 error.

Fixes: a9e821b89d ("arm64: Add KRYO4XX gold CPU cores to erratum list 1463225 and 1418040")
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Reviewed-by: Sai Prakash Ranjan <saiprakash.ranjan@codeaurora.org>
Link: https://lore.kernel.org/linux-arm-kernel/CA+G9fYs3EavpU89-rTQfqQ9GgxAMgMAk7jiiVrfP0yxj5s+Q6g@mail.gmail.com/
Link: https://lore.kernel.org/r/20200709051345.14544-1-f.fainelli@gmail.com
Signed-off-by: Will Deacon <will@kernel.org>
2020-07-09 09:42:24 +01:00
Wei Li
8523c00626 arm64: kgdb: Fix single-step exception handling oops
After entering kdb due to breakpoint, when we execute 'ss' or 'go' (will
delay installing breakpoints, do single-step first), it won't work
correctly, and it will enter kdb due to oops.

It's because the reason gotten in kdb_stub() is not as expected, and it
seems that the ex_vector for single-step should be 0, like what arch
powerpc/sh/parisc has implemented.

Before the patch:
Entering kdb (current=0xffff8000119e2dc0, pid 0) on processor 0 due to Keyboard Entry
[0]kdb> bp printk
Instruction(i) BP #0 at 0xffff8000101486cc (printk)
    is enabled   addr at ffff8000101486cc, hardtype=0 installed=0

[0]kdb> g

/ # echo h > /proc/sysrq-trigger

Entering kdb (current=0xffff0000fa878040, pid 266) on processor 3 due to Breakpoint @ 0xffff8000101486cc
[3]kdb> ss

Entering kdb (current=0xffff0000fa878040, pid 266) on processor 3 Oops: (null)
due to oops @ 0xffff800010082ab8
CPU: 3 PID: 266 Comm: sh Not tainted 5.7.0-rc4-13839-gf0e5ad491718 #6
Hardware name: linux,dummy-virt (DT)
pstate: 00000085 (nzcv daIf -PAN -UAO)
pc : el1_irq+0x78/0x180
lr : __handle_sysrq+0x80/0x190
sp : ffff800015003bf0
x29: ffff800015003d20 x28: ffff0000fa878040
x27: 0000000000000000 x26: ffff80001126b1f0
x25: ffff800011b6a0d8 x24: 0000000000000000
x23: 0000000080200005 x22: ffff8000101486cc
x21: ffff800015003d30 x20: 0000ffffffffffff
x19: ffff8000119f2000 x18: 0000000000000000
x17: 0000000000000000 x16: 0000000000000000
x15: 0000000000000000 x14: 0000000000000000
x13: 0000000000000000 x12: 0000000000000000
x11: 0000000000000000 x10: 0000000000000000
x9 : 0000000000000000 x8 : ffff800015003e50
x7 : 0000000000000002 x6 : 00000000380b9990
x5 : ffff8000106e99e8 x4 : ffff0000fadd83c0
x3 : 0000ffffffffffff x2 : ffff800011b6a0d8
x1 : ffff800011b6a000 x0 : ffff80001130c9d8
Call trace:
 el1_irq+0x78/0x180
 printk+0x0/0x84
 write_sysrq_trigger+0xb0/0x118
 proc_reg_write+0xb4/0xe0
 __vfs_write+0x18/0x40
 vfs_write+0xb0/0x1b8
 ksys_write+0x64/0xf0
 __arm64_sys_write+0x14/0x20
 el0_svc_common.constprop.2+0xb0/0x168
 do_el0_svc+0x20/0x98
 el0_sync_handler+0xec/0x1a8
 el0_sync+0x140/0x180

[3]kdb>

After the patch:
Entering kdb (current=0xffff8000119e2dc0, pid 0) on processor 0 due to Keyboard Entry
[0]kdb> bp printk
Instruction(i) BP #0 at 0xffff8000101486cc (printk)
    is enabled   addr at ffff8000101486cc, hardtype=0 installed=0

[0]kdb> g

/ # echo h > /proc/sysrq-trigger

Entering kdb (current=0xffff0000fa852bc0, pid 268) on processor 0 due to Breakpoint @ 0xffff8000101486cc
[0]kdb> g

Entering kdb (current=0xffff0000fa852bc0, pid 268) on processor 0 due to Breakpoint @ 0xffff8000101486cc
[0]kdb> ss

Entering kdb (current=0xffff0000fa852bc0, pid 268) on processor 0 due to SS trap @ 0xffff800010082ab8
[0]kdb>

Fixes: 44679a4f14 ("arm64: KGDB: Add step debugging support")
Signed-off-by: Wei Li <liwei391@huawei.com>
Tested-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/r/20200509214159.19680-2-liwei391@huawei.com
Signed-off-by: Will Deacon <will@kernel.org>
2020-07-08 22:18:54 +01:00
Will Deacon
8c3001b925 arm64: entry: Tidy up block comments and label numbers
Continually butchering our entry code with CPU errata workarounds has
led to it looking a little scruffy. Consistently used /* */ comment
style for multi-line block comments and ensure that small numeric labels
use consecutive integers.

No functional change, but the state of things was irritating.

Signed-off-by: Will Deacon <will@kernel.org>
2020-07-08 22:13:33 +01:00
Marc Zyngier
dc802f2bc0 arm64: Rework ARM_ERRATUM_1414080 handling
The current handling of erratum 1414080 has the side effect that
cntkctl_el1 can get changed for both 32 and 64bit tasks.

This isn't a problem so far, but if we ever need to mitigate another
of these errata on the 64bit side, we'd better keep the messing with
cntkctl_el1 local to 32bit tasks.

For that, make sure that on entering the kernel from a 32bit tasks,
userspace access to cntvct gets enabled, and disabled returning to
userspace, while it never gets changed for 64bit tasks.

Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20200706163802.1836732-5-maz@kernel.org
[will: removed branch instructions per Mark's review comments]
Signed-off-by: Will Deacon <will@kernel.org>
2020-07-08 22:07:19 +01:00
Kevin Hao
b8c1c9fe6a arm64: entry: Fix the typo in the comment of el1_dbg()
The function name should be local_daif_mask().

Signed-off-by: Kevin Hao <haokexin@gmail.com>
Acked-by: Mark Rutlamd <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20200417103212.45812-2-haokexin@gmail.com
Signed-off-by: Will Deacon <will@kernel.org>
2020-07-08 21:44:40 +01:00
Anshuman Khandual
c6c83d757a arm64/cpufeature: Validate feature bits spacing in arm64_ftr_regs[]
arm64_feature_bits for a register in arm64_ftr_regs[] are in a descending
order as per their shift values. Validate that these features bits are
defined correctly and do not overlap with each other. This check protects
against any inadvertent erroneous changes to the register definitions.

Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Suzuki K Poulose <suzuki.poulose@arm.com>
Cc: Mark Brown <broonie@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Link: https://lore.kernel.org/r/1594131793-9498-1-git-send-email-anshuman.khandual@arm.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2020-07-07 16:02:59 +01:00
Marc Zyngier
e47c2055c6 KVM: arm64: Make struct kvm_regs userspace-only
struct kvm_regs is used by userspace to indicate which register gets
accessed by the {GET,SET}_ONE_REG API. But as we're about to refactor
the layout of the in-kernel register structures, we need the kernel to
move away from it.

Let's make kvm_regs userspace only, and let the kernel map it to its own
internal representation.

Reviewed-by: James Morse <james.morse@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
2020-07-07 09:28:38 +01:00
Marc Zyngier
ae4bffb555 Merge branch 'kvm-arm64/ttl-for-arm64' into HEAD
Signed-off-by: Marc Zyngier <maz@kernel.org>
2020-07-07 09:28:24 +01:00
Marc Zyngier
552ae76fac arm64: Detect the ARMv8.4 TTL feature
In order to reduce the cost of TLB invalidation, the ARMv8.4 TTL
feature allows TLBs to be issued with a level allowing for quicker
invalidation.

Let's detect the feature for now. Further patches will implement
its actual usage.

Reviewed-by : Suzuki K Polose <suzuki.poulose@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
2020-07-07 09:27:14 +01:00
David Brazdil
c04dd455eb KVM: arm64: Compile remaining hyp/ files for both VHE/nVHE
The following files in hyp/ contain only code shared by VHE/nVHE:
  vgic-v3-sr.c, aarch32.c, vgic-v2-cpuif-proxy.c, entry.S, fpsimd.S
Compile them under both configurations. Deletions in image-vars.h reflect
eliminated dependencies of nVHE code on the rest of the kernel.

Signed-off-by: David Brazdil <dbrazdil@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20200625131420.71444-14-dbrazdil@google.com
2020-07-05 18:38:42 +01:00
David Brazdil
9aebdea494 KVM: arm64: Duplicate hyp/timer-sr.c for VHE/nVHE
timer-sr.c contains a HVC handler for setting CNTVOFF_EL2 and two helper
functions for controlling access to physical counter. The former is used by
both VHE/nVHE and is duplicated, the latter are used only by nVHE and moved
to nvhe/timer-sr.c.

Signed-off-by: David Brazdil <dbrazdil@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20200625131420.71444-13-dbrazdil@google.com
2020-07-05 18:38:38 +01:00
David Brazdil
13aeb9b400 KVM: arm64: Split hyp/sysreg-sr.c to VHE/nVHE
sysreg-sr.c contains KVM's code for saving/restoring system registers, with
some code shared between VHE/nVHE. These common routines are moved to
a header file, VHE-specific code is moved to vhe/sysreg-sr.c and nVHE-specific
code to nvhe/sysreg-sr.c.

Signed-off-by: David Brazdil <dbrazdil@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20200625131420.71444-12-dbrazdil@google.com
2020-07-05 18:38:29 +01:00
David Brazdil
d400c5b202 KVM: arm64: Split hyp/debug-sr.c to VHE/nVHE
debug-sr.c contains KVM's code for context-switching debug registers, with some
code shared between VHE/nVHE. These common routines are moved to a header file,
VHE-specific code is moved to vhe/debug-sr.c and nVHE-specific code to
nvhe/debug-sr.c.

Functions are slightly refactored to move code hidden behind `has_vhe()` checks
to the corresponding .c files.

Signed-off-by: David Brazdil <dbrazdil@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20200625131420.71444-11-dbrazdil@google.com
2020-07-05 18:38:25 +01:00
David Brazdil
09cf57eba3 KVM: arm64: Split hyp/switch.c to VHE/nVHE
switch.c implements context-switching for KVM, with large parts shared between
VHE/nVHE. These common routines are moved to a header file, VHE-specific code
is moved to vhe/switch.c and nVHE-specific code is moved to nvhe/switch.c.

Previously __kvm_vcpu_run needed a different symbol name for VHE/nVHE. This
is cleaned up and the caller in arm.c simplified.

Signed-off-by: David Brazdil <dbrazdil@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20200625131420.71444-10-dbrazdil@google.com
2020-07-05 18:38:21 +01:00
David Brazdil
e03fa29164 KVM: arm64: Duplicate hyp/tlb.c for VHE/nVHE
tlb.c contains code for flushing the TLB, with code shared between VHE/nVHE.
Because common code is small, duplicate tlb.c and specialize each copy for
VHE/nVHE.

Signed-off-by: David Brazdil <dbrazdil@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20200625131420.71444-9-dbrazdil@google.com
2020-07-05 18:38:17 +01:00
Andrew Scull
208243c752 KVM: arm64: Move hyp-init.S to nVHE
hyp-init.S contains the identity mapped initialisation code for the
non-VHE code that runs at EL2. It is only used for non-VHE.

Adjust code that calls into this to use the prefixed symbol name.

Signed-off-by: Andrew Scull <ascull@google.com>
Signed-off-by: David Brazdil <dbrazdil@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20200625131420.71444-8-dbrazdil@google.com
2020-07-05 18:38:12 +01:00
David Brazdil
b877e9849d KVM: arm64: Build hyp-entry.S separately for VHE/nVHE
hyp-entry.S contains implementation of KVM hyp vectors. This code is mostly
shared between VHE/nVHE, therefore compile it under both VHE and nVHE build
rules. nVHE-specific host HVC handler is hidden behind __KVM_NVHE_HYPERVISOR__.

Adjust code which selects which KVM hyp vecs to install to choose the correct
VHE/nVHE symbol.

Signed-off-by: David Brazdil <dbrazdil@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20200625131420.71444-7-dbrazdil@google.com
2020-07-05 18:38:08 +01:00
Andrew Scull
f50b6f6ae1 KVM: arm64: Handle calls to prefixed hyp functions
Once hyp functions are moved to a hyp object, they will have prefixed symbols.
This change declares and gets the address of the prefixed version for calls to
the hyp functions.

To aid migration, the hyp functions that have not yet moved have their prefixed
versions aliased to their non-prefixed version. This begins with all the hyp
functions being listed and will reduce to none of them once the migration is
complete.

Signed-off-by: Andrew Scull <ascull@google.com>

[David: Extracted kvm_call_hyp nVHE branches into own helper macros, added
        comments around symbol aliases.]

Signed-off-by: David Brazdil <dbrazdil@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20200625131420.71444-6-dbrazdil@google.com
2020-07-05 18:38:04 +01:00
David Brazdil
7621712918 KVM: arm64: Add build rules for separate VHE/nVHE object files
Add new folders arch/arm64/kvm/hyp/{vhe,nvhe} and Makefiles for building code
that runs in EL2 under VHE/nVHE KVM, repsectivelly. Add an include folder for
hyp-specific header files which will include code common to VHE/nVHE.

Build nVHE code with -D__KVM_NVHE_HYPERVISOR__, VHE code with
-D__KVM_VHE_HYPERVISOR__.

Under nVHE compile each source file into a `.hyp.tmp.o` object first, then
prefix all its symbols with "__kvm_nvhe_" using `objcopy` and produce
a `.hyp.o`. Suffixes were chosen so that it would be possible for VHE and nVHE
to share some source files, but compiled with different CFLAGS.

The nVHE ELF symbol prefix is added to kallsyms.c as ignored. EL2-only symbols
will never appear in EL1 stack traces.

Due to symbol prefixing, add a section in image-vars.h for aliases of symbols
that are defined in nVHE EL2 and accessed by kernel in EL1 or vice versa.

Signed-off-by: David Brazdil <dbrazdil@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20200625131420.71444-4-dbrazdil@google.com
2020-07-05 18:37:55 +01:00
Linus Torvalds
ec84c3f6ef arm64 fixes for -rc4
- Fix alternative patching for very large kernel images and modules
 
 - Hook up existing CPU errata workarounds for Qualcomm Kryo CPUs
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Merge tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux

Pull arm64 fixes from Will Deacon:
 "Nothing earth-shattering, really - some CPU errata workarounds (one
  day they'll get it right, ha!) and a fix for a boot failure with very
  large kernel images where the alternative patching gets confused when
  patching relative branches using veneers.

   - Fix alternative patching for very large kernel images and modules

   - Hook up existing CPU errata workarounds for Qualcomm Kryo CPUs"

* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
  arm64: Add KRYO4XX silver CPU cores to erratum list 1530923 and 1024718
  arm64: Add KRYO4XX gold CPU cores to erratum list 1463225 and 1418040
  arm64: Add MIDR value for KRYO4XX gold CPU cores
  arm64/alternatives: use subsections for replacement sequences
2020-07-04 14:43:26 -07:00
Christian Brauner
714acdbd1c
arch: rename copy_thread_tls() back to copy_thread()
Now that HAVE_COPY_THREAD_TLS has been removed, rename copy_thread_tls()
back simply copy_thread(). It's a simpler name, and doesn't imply that only
tls is copied here. This finishes an outstanding chunk of internal process
creation work since we've added clone3().

Cc: linux-arch@vger.kernel.org
Acked-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>A
Acked-by: Stafford Horne <shorne@gmail.com>
Acked-by: Greentime Hu <green.hu@gmail.com>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>A
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
2020-07-04 23:41:37 +02:00
Christoph Hellwig
a3a66c3822 vmalloc: fix the owner argument for the new __vmalloc_node_range callers
Fix the recently added new __vmalloc_node_range callers to pass the
correct values as the owner for display in /proc/vmallocinfo.

Fixes: 800e26b813 ("x86/hyperv: allocate the hypercall page with only read and execute bits")
Fixes: 10d5e97c1b ("arm64: use PAGE_KERNEL_ROX directly in alloc_insn_page")
Fixes: 7a0e27b2a0 ("mm: remove vmalloc_exec")
Reported-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/20200627075649.2455097-1-hch@lst.de
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-07-03 16:15:25 -07:00
Anshuman Khandual
8d3154afc1 arm64/cpufeature: Replace all open bits shift encodings with macros
There are many open bits shift encodings for various CPU ID registers that
are scattered across cpufeature. This replaces them with register specific
sensible macro definitions. This should not have any functional change.

Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Marc Zyngier <maz@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: James Morse <james.morse@arm.com>
Cc: Suzuki K Poulose <suzuki.poulose@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Link: https://lore.kernel.org/r/1593748297-1965-5-git-send-email-anshuman.khandual@arm.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2020-07-03 16:52:04 +01:00
Anshuman Khandual
356fdfbe87 arm64/cpufeature: Add remaining feature bits in ID_AA64MMFR2 register
Enable EVT, BBM, TTL, IDS, ST, NV and CCIDX features bits in ID_AA64MMFR2
register as per ARM DDI 0487F.a specification.

Suggested-by: Will Deacon <will@kernel.org>
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Suzuki K Poulose <suzuki.poulose@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Link: https://lore.kernel.org/r/1593748297-1965-4-git-send-email-anshuman.khandual@arm.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2020-07-03 16:52:04 +01:00
Anshuman Khandual
853772ba80 arm64/cpufeature: Add remaining feature bits in ID_AA64MMFR1 register
Enable ETS, TWED, XNX and SPECSEI features bits in ID_AA64MMFR1 register as
per ARM DDI 0487F.a specification.

Suggested-by: Will Deacon <will@kernel.org>
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Suzuki K Poulose <suzuki.poulose@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Link: https://lore.kernel.org/r/1593748297-1965-3-git-send-email-anshuman.khandual@arm.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2020-07-03 16:52:04 +01:00
Anshuman Khandual
bc67f10ad1 arm64/cpufeature: Add remaining feature bits in ID_AA64MMFR0 register
Enable EVC, FGT, EXS features bits in ID_AA64MMFR0 register as per ARM DDI
0487F.a specification.

Suggested-by: Will Deacon <will@kernel.org>
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Suzuki K Poulose <suzuki.poulose@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Link: https://lore.kernel.org/r/1593748297-1965-2-git-send-email-anshuman.khandual@arm.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2020-07-03 16:52:04 +01:00
Sai Prakash Ranjan
9b23d95c53 arm64: Add KRYO4XX silver CPU cores to erratum list 1530923 and 1024718
KRYO4XX silver/LITTLE CPU cores with revision r1p0 are affected by
erratum 1530923 and 1024718, so add them to the respective list.
The variant and revision bits are implementation defined and are
different from the their Cortex CPU counterparts on which they are
based on, i.e., r1p0 is equivalent to rdpe.

Signed-off-by: Sai Prakash Ranjan <saiprakash.ranjan@codeaurora.org>
Link: https://lore.kernel.org/r/7013e8a3f857ca7e82863cc9e34a614293d7f80c.1593539394.git.saiprakash.ranjan@codeaurora.org
Signed-off-by: Will Deacon <will@kernel.org>
2020-07-03 16:39:16 +01:00
Sai Prakash Ranjan
a9e821b89d arm64: Add KRYO4XX gold CPU cores to erratum list 1463225 and 1418040
KRYO4XX gold/big CPU core revisions r0p0 to r3p1 are affected by
erratum 1463225 and 1418040, so add them to the respective list.
The variant and revision bits are implementation defined and are
different from the their Cortex CPU counterparts on which they are
based on, i.e., (r0p0 to r3p1) is equivalent to (rcpe to rfpf).

Signed-off-by: Sai Prakash Ranjan <saiprakash.ranjan@codeaurora.org>
Link: https://lore.kernel.org/r/83780e80c6377c12ca51b5d53186b61241685e49.1593539394.git.saiprakash.ranjan@codeaurora.org
Signed-off-by: Will Deacon <will@kernel.org>
2020-07-03 16:39:16 +01:00
Bhupesh Sharma
bbdbc11804 arm64/crash_core: Export TCR_EL1.T1SZ in vmcoreinfo
TCR_EL1.TxSZ, which controls the VA space size, is configured by a
single kernel image to support either 48-bit or 52-bit VA space.

If the ARMv8.2-LVA optional feature is present and we are running
with a 64KB page size, then it is possible to use 52-bits of address
space for both userspace and kernel addresses. However, any kernel
binary that supports 52-bit must also be able to fall back to 48-bit
at early boot time if the hardware feature is not present.

Since TCR_EL1.T1SZ indicates the size of the memory region addressed by
TTBR1_EL1, export the same in vmcoreinfo. User-space utilities like
makedumpfile and crash-utility need to read this value from vmcoreinfo
for determining if a virtual address lies in the linear map range.

While at it also add documentation for TCR_EL1.T1SZ variable being
added to vmcoreinfo.

It indicates the size offset of the memory region addressed by
TTBR1_EL1.

Signed-off-by: Bhupesh Sharma <bhsharma@redhat.com>
Tested-by: John Donnelly <john.p.donnelly@oracle.com>
Tested-by: Kamlakant Patel <kamlakantp@marvell.com>
Tested-by: Amit Daniel Kachhap <amit.kachhap@arm.com>
Reviewed-by: James Morse <james.morse@arm.com>
Reviewed-by: Amit Daniel Kachhap <amit.kachhap@arm.com>
Cc: James Morse <james.morse@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Steve Capper <steve.capper@arm.com>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Dave Anderson <anderson@redhat.com>
Cc: Kazuhito Hagio <k-hagio@ab.jp.nec.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Cc: kexec@lists.infradead.org
Link: https://lore.kernel.org/r/1589395957-24628-3-git-send-email-bhsharma@redhat.com
[catalin.marinas@arm.com: removed vabits_actual from the commit log]
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2020-07-02 17:56:49 +01:00
Anshuman Khandual
638d503130 arm64/panic: Unify all three existing notifier blocks
Currently there are three different registered panic notifier blocks. This
unifies all of them into a single one i.e arm64_panic_block, hence reducing
code duplication and required calling sequence during panic. This preserves
the existing dump sequence. While here, just use device_initcall() directly
instead of __initcall() which has been a legacy alias for the earlier. This
replacement is a pure cleanup with no functional implications.

Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Steve Capper <steve.capper@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Link: https://lore.kernel.org/r/1593405511-7625-1-git-send-email-anshuman.khandual@arm.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2020-07-02 15:44:50 +01:00
Ard Biesheuvel
f7b93d4294 arm64/alternatives: use subsections for replacement sequences
When building very large kernels, the logic that emits replacement
sequences for alternatives fails when relative branches are present
in the code that is emitted into the .altinstr_replacement section
and patched in at the original site and fixed up. The reason is that
the linker will insert veneers if relative branches go out of range,
and due to the relative distance of the .altinstr_replacement from
the .text section where its branch targets usually live, veneers
may be emitted at the end of the .altinstr_replacement section, with
the relative branches in the sequence pointed at the veneers instead
of the actual target.

The alternatives patching logic will attempt to fix up the branch to
point to its original target, which will be the veneer in this case,
but given that the patch site is likely to be far away as well, it
will be out of range and so patching will fail. There are other cases
where these veneers are problematic, e.g., when the target of the
branch is in .text while the patch site is in .init.text, in which
case putting the replacement sequence inside .text may not help either.

So let's use subsections to emit the replacement code as closely as
possible to the patch site, to ensure that veneers are only likely to
be emitted if they are required at the patch site as well, in which
case they will be in range for the replacement sequence both before
and after it is transported to the patch site.

This will prevent alternative sequences in non-init code from being
released from memory after boot, but this is tolerable given that the
entire section is only 512 KB on an allyesconfig build (which weighs in
at 500+ MB for the entire Image). Also, note that modules today carry
the replacement sequences in non-init sections as well, and any of
those that target init code will be emitted into init sections after
this change.

This fixes an early crash when booting an allyesconfig kernel on a
system where any of the alternatives sequences containing relative
branches are activated at boot (e.g., ARM64_HAS_PAN on TX2)

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Cc: Suzuki K Poulose <suzuki.poulose@arm.com>
Cc: James Morse <james.morse@arm.com>
Cc: Andre Przywara <andre.przywara@arm.com>
Cc: Dave P Martin <dave.martin@arm.com>
Link: https://lore.kernel.org/r/20200630081921.13443-1-ardb@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
2020-07-02 12:57:17 +01:00
Saravana Kannan
d4e0340919 arm64/module: Optimize module load time by optimizing PLT counting
When loading a module, module_frob_arch_sections() tries to figure out
the number of PLTs that'll be needed to handle all the RELAs. While
doing this, it tries to dedupe PLT allocations for multiple
R_AARCH64_CALL26 relocations to the same symbol. It does the same for
R_AARCH64_JUMP26 relocations.

To make checks for duplicates easier/faster, it sorts the relocation
list by type, symbol and addend. That way, to check for a duplicate
relocation, it just needs to compare with the previous entry.

However, sorting the entire relocation array is unnecessary and
expensive (O(n log n)) because there are a lot of other relocation types
that don't need deduping or can't be deduped.

So this commit partitions the array into entries that need deduping and
those that don't. And then sorts just the part that needs deduping. And
when CONFIG_RANDOMIZE_BASE is disabled, the sorting is skipped entirely
because PLTs are not allocated for R_AARCH64_CALL26 and R_AARCH64_JUMP26
if it's disabled.

This gives significant reduction in module load time for modules with
large number of relocations with no measurable impact on modules with a
small number of relocations. In my test setup with CONFIG_RANDOMIZE_BASE
enabled, these were the results for a few downstream modules:

Module		Size (MB)
wlan		14
video codec	3.8
drm		1.8
IPA		2.5
audio		1.2
gpu		1.8

Without this patch:
Module		Number of entries sorted	Module load time (ms)
wlan		243739				283
video codec	74029				138
drm		53837				67
IPA		42800				90
audio		21326				27
gpu		20967				32

Total time to load all these module: 637 ms

With this patch:
Module		Number of entries sorted	Module load time (ms)
wlan		22454				61
video codec	10150				47
drm		13014				40
IPA		8097				63
audio		4606				16
gpu		6527				20

Total time to load all these modules: 247

Time saved during boot for just these 6 modules: 390 ms

Signed-off-by: Saravana Kannan <saravanak@google.com>
Acked-by: Will Deacon <will@kernel.org>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Link: https://lore.kernel.org/r/20200623011803.91232-1-saravanak@google.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2020-07-02 12:17:13 +01:00
Linus Torvalds
8530684fd3 arm64 fixes for -rc3
- Fix unwinding through vDSO sigreturn trampoline
 
 - Fix build warnings by raising minimum LD version for PAC
 
 - Whitelist some Kryo Cortex-A55 derivatives for Meltdown and SSB
 
 - Fix perf register PC reporting for compat tasks
 
 - Fix 'make clean' warning for arm64 signal selftests
 
 - Fix ftrace when BTI is compiled in
 
 - Avoid building the compat vDSO using GCC plugins
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Merge tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux

Pull arm64 fixes from Will Deacon:
 "The big fix here is to our vDSO sigreturn trampoline as, after a
  painfully long stint of debugging, it turned out that fixing some of
  our CFI directives in the merge window lit up a bunch of logic in
  libgcc which has been shown to SEGV in some cases during asynchronous
  pthread cancellation.

  It looks like we can fix this by extending the directives to restore
  most of the interrupted register state from the sigcontext, but it's
  risky and hard to test so we opted to remove the CFI directives for
  now and rely on the unwinder fallback path like we used to.

   - Fix unwinding through vDSO sigreturn trampoline

   - Fix build warnings by raising minimum LD version for PAC

   - Whitelist some Kryo Cortex-A55 derivatives for Meltdown and SSB

   - Fix perf register PC reporting for compat tasks

   - Fix 'make clean' warning for arm64 signal selftests

   - Fix ftrace when BTI is compiled in

   - Avoid building the compat vDSO using GCC plugins"

* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
  arm64: Add KRYO{3,4}XX silver CPU cores to SSB safelist
  arm64: perf: Report the PC value in REGS_ABI_32 mode
  kselftest: arm64: Remove redundant clean target
  arm64: kpti: Add KRYO{3, 4}XX silver CPU cores to kpti safelist
  arm64: Don't insert a BTI instruction at inner labels
  arm64: vdso: Don't use gcc plugins for building vgettimeofday.c
  arm64: vdso: Only pass --no-eh-frame-hdr when linker supports it
  arm64: Depend on newer binutils when building PAC
  arm64: compat: Remove 32-bit sigreturn code from the vDSO
  arm64: compat: Always use sigpage for sigreturn trampoline
  arm64: compat: Allow 32-bit vdso and sigpage to co-exist
  arm64: vdso: Disable dwarf unwinding through the sigreturn trampoline
2020-06-27 08:47:18 -07:00
Christoph Hellwig
10d5e97c1b arm64: use PAGE_KERNEL_ROX directly in alloc_insn_page
Use PAGE_KERNEL_ROX directly instead of allocating RWX and setting the
page read-only just after the allocation.

Link: http://lkml.kernel.org/r/20200618064307.32739-3-hch@lst.de
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: David Hildenbrand <david@redhat.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Dexuan Cui <decui@microsoft.com>
Cc: Jessica Yu <jeyu@kernel.org>
Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: Wei Liu <wei.liu@kernel.org>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-26 00:27:38 -07:00
Al Viro
d547175b54 arm64: sanitize compat_ptrace_write_user()
don't bother with copy_regset_from_user() (not to mention
set_fs())

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-06-26 01:02:35 -04:00
Al Viro
b44f384074 arm64: get rid of copy_regset_to_user() in compat_ptrace_read_user()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-06-26 01:02:35 -04:00
Al Viro
a96dacf988 arm64: take fetching compat reg out of pt_regs into a new helper
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-06-26 01:02:34 -04:00
Sai Prakash Ranjan
108447fd0d arm64: Add KRYO{3,4}XX silver CPU cores to SSB safelist
QCOM KRYO{3,4}XX silver/LITTLE CPU cores are based on
Cortex-A55 and are SSB safe, hence add them to SSB
safelist -> arm64_ssb_cpus[].

Reported-by: Stephen Boyd <swboyd@chromium.org>
Signed-off-by: Sai Prakash Ranjan <saiprakash.ranjan@codeaurora.org>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/r/20200625103123.7240-1-saiprakash.ranjan@codeaurora.org
Signed-off-by: Will Deacon <will@kernel.org>
2020-06-25 20:18:57 +01:00
Jiping Ma
8dfe804a40 arm64: perf: Report the PC value in REGS_ABI_32 mode
A 32-bit perf querying the registers of a compat task using REGS_ABI_32
will receive zeroes from w15, when it expects to find the PC.

Return the PC value for register dwarf register 15 when returning register
values for a compat task to perf.

Cc: <stable@vger.kernel.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Jiping Ma <jiping.ma2@windriver.com>
Link: https://lore.kernel.org/r/1589165527-188401-1-git-send-email-jiping.ma2@windriver.com
[will: Shuffled code and added a comment]
Signed-off-by: Will Deacon <will@kernel.org>
2020-06-25 14:47:04 +01:00
Sai Prakash Ranjan
f4617be35b arm64: kpti: Add KRYO{3, 4}XX silver CPU cores to kpti safelist
QCOM KRYO{3,4}XX silver/LITTLE CPU cores are based on Cortex-A55
and are meltdown safe, hence add them to kpti_safe_list[].

Signed-off-by: Sai Prakash Ranjan <saiprakash.ranjan@codeaurora.org>
Link: https://lore.kernel.org/r/20200624123406.3472-1-saiprakash.ranjan@codeaurora.org
Signed-off-by: Will Deacon <will@kernel.org>
2020-06-24 14:25:06 +01:00
Alexander Popov
e56404e8e4 arm64: vdso: Don't use gcc plugins for building vgettimeofday.c
Don't use gcc plugins for building arch/arm64/kernel/vdso/vgettimeofday.c
to avoid unneeded instrumentation.

Signed-off-by: Alexander Popov <alex.popov@linux.com>
Link: https://lore.kernel.org/r/20200624123330.83226-4-alex.popov@linux.com
Signed-off-by: Will Deacon <will@kernel.org>
2020-06-24 14:04:44 +01:00
Will Deacon
49a3b0e1c0 arm64: vdso: Only pass --no-eh-frame-hdr when linker supports it
Commit 87676cfca1 ("arm64: vdso: Disable dwarf unwinding through the
sigreturn trampoline") unconditionally passes the '--no-eh-frame-hdr'
option to the linker when building the native vDSO in an attempt to
prevent generation of the .eh_frame_hdr section, the presence of which
has been implicated in segfaults originating from the libgcc unwinder.

Unfortunately, not all versions of binutils support this option, which
has been shown to cause build failures in linux-next:

  |   CALL    scripts/atomic/check-atomics.sh
  |   CALL    scripts/checksyscalls.sh
  |   LD      arch/arm64/kernel/vdso/vdso.so.dbg
  | ld: unrecognized option '--no-eh-frame-hdr'
  | ld: use the --help option for usage information
  | arch/arm64/kernel/vdso/Makefile:64: recipe for target
  | 'arch/arm64/kernel/vdso/vdso.so.dbg' failed
  | make[1]: *** [arch/arm64/kernel/vdso/vdso.so.dbg] Error 1
  | arch/arm64/Makefile:175: recipe for target 'vdso_prepare' failed
  | make: *** [vdso_prepare] Error 2

Only link the vDSO with '--no-eh-frame-hdr' when the linker supports it.
If we end up with the section due to linker defaults, the absence of CFI
information in the sigreturn trampoline will prevent the unwinder from
breaking.

Link: https://lore.kernel.org/r/7a7e31a8-9a7b-2428-ad83-2264f20bdc2d@hisilicon.com
Fixes: 87676cfca1 ("arm64: vdso: Disable dwarf unwinding through the sigreturn trampoline")
Reported-by: Shaokun Zhang <zhangshaokun@hisilicon.com>
Tested-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Will Deacon <will@kernel.org>
2020-06-24 13:23:10 +01:00
Will Deacon
2d071968a4 arm64: compat: Remove 32-bit sigreturn code from the vDSO
The sigreturn code in the compat vDSO is unused. Remove it.

Reviewed-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
2020-06-23 14:56:39 +01:00
Will Deacon
8e411be6aa arm64: compat: Always use sigpage for sigreturn trampoline
The 32-bit sigreturn trampoline in the compat sigpage matches the binary
representation of the arch/arm/ sigpage exactly. This is important for
debuggers (e.g. GDB) and unwinders (e.g. libunwind) since they rely
on matching the instruction sequence in order to identify that they are
unwinding through a signal. The same cannot be said for the sigreturn
trampoline in the compat vDSO, which defeats the unwinder heuristics and
instead attempts to use unwind directives for the unwinding. This is in
contrast to arch/arm/, which never uses the vDSO for sigreturn.

Ensure compatibility with arch/arm/ and existing unwinders by always
using the sigpage for the sigreturn trampoline, regardless of the
presence of the compat vDSO.

Reviewed-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
2020-06-23 14:56:24 +01:00
Will Deacon
a39060b009 arm64: compat: Allow 32-bit vdso and sigpage to co-exist
In preparation for removing the signal trampoline from the compat vDSO,
allow the sigpage and the compat vDSO to co-exist.

For the moment the vDSO signal trampoline will still be used when built.
Subsequent patches will move to the sigpage consistently.

Acked-by: Dave Martin <Dave.Martin@arm.com>
Reviewed-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
2020-06-23 14:47:03 +01:00