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
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>
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>
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>
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>
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
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>
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
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>
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>
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>
Commit 7e9f5e6629 ("arm64: vdso: Add --eh-frame-hdr to ldflags") results
in a .eh_frame_hdr section for the vDSO, which in turn causes the libgcc
unwinder to unwind out of signal handlers using the .eh_frame information
populated by our .cfi directives. In conjunction with a4eb355a3f
("arm64: vdso: Fix CFI directives in sigreturn trampoline"), this has
been shown to cause segmentation faults originating from within the
unwinder during thread cancellation:
| Thread 14 "virtio-net-rx" received signal SIGSEGV, Segmentation fault.
| 0x0000000000435e24 in uw_frame_state_for ()
| (gdb) bt
| #0 0x0000000000435e24 in uw_frame_state_for ()
| #1 0x0000000000436e88 in _Unwind_ForcedUnwind_Phase2 ()
| #2 0x00000000004374d8 in _Unwind_ForcedUnwind ()
| #3 0x0000000000428400 in __pthread_unwind (buf=<optimized out>) at unwind.c:121
| #4 0x0000000000429808 in __do_cancel () at ./pthreadP.h:304
| #5 sigcancel_handler (sig=32, si=0xffff33c743f0, ctx=<optimized out>) at nptl-init.c:200
| #6 sigcancel_handler (sig=<optimized out>, si=0xffff33c743f0, ctx=<optimized out>) at nptl-init.c:165
| #7 <signal handler called>
| #8 futex_wait_cancelable (private=0, expected=0, futex_word=0x3890b708) at ../sysdeps/unix/sysv/linux/futex-internal.h:88
After considerable bashing of heads, it appears that our CFI directives
for unwinding out of the sigreturn trampoline are only processed by libgcc
when both a .eh_frame_hdr section is present *and* the mysterious NOP is
covered by an entry in .eh_frame. With both of these now in place, it has
highlighted that our CFI directives are not comprehensive enough to
restore the stack pointer of the interrupted context. This results in libgcc
falling back to an arm64-specific unwinder after computing a bogus PC value
from the unwind tables. The unwinder promptly dereferences this bogus address
in an attempt to see if the pointed-to instruction sequence looks like
the sigreturn trampoline.
Restore the old unwind behaviour, which relied solely on heuristics in
the unwinder, by removing the .eh_frame_hdr section from the vDSO and
commenting out the insufficient CFI directives for now. Add comments to
explain the current, miserable state of affairs.
Cc: Tamas Zsoldos <tamas.zsoldos@arm.com>
Cc: Szabolcs Nagy <szabolcs.nagy@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Daniel Kiss <daniel.kiss@arm.com>
Acked-by: Dave Martin <Dave.Martin@arm.com>
Reviewed-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
Reported-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Will Deacon <will@kernel.org>
Pull arm64 fixes from Will Deacon:
"Unfortunately, we still have a number of outstanding issues so there
will be more fixes to come, but this lot are a good start.
- Fix handling of watchpoints triggered by uaccess routines
- Fix initialisation of gigantic pages for CMA buffers
- Raise minimum clang version for BTI to avoid miscompilation
- Fix data race in SVE vector length configuration code
- Ensure address tags are ignored in kern_addr_valid()
- Dump register state on fatal BTI exception
- kexec_file() cleanup to use struct_size() macro"
* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
arm64: hw_breakpoint: Don't invoke overflow handler on uaccess watchpoints
arm64: kexec_file: Use struct_size() in kmalloc()
arm64: mm: reserve hugetlb CMA after numa_init
arm64: bti: Require clang >= 10.0.1 for in-kernel BTI support
arm64: sve: Fix build failure when ARM64_SVE=y and SYSCTL=n
arm64: pgtable: Clear the GP bit for non-executable kernel pages
arm64: mm: reset address tag set by kasan sw tagging
arm64: traps: Dump registers prior to panic() in bad_mode()
arm64/sve: Eliminate data races on sve_default_vl
docs/arm64: Fix typo'd #define in sve.rst
arm64: remove TEXT_OFFSET randomization
Better describe what this helper does, and match the naming of
copy_from_kernel_nofault.
Also switch the argument order around, so that it acts and looks
like get_user().
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Unprivileged memory accesses generated by the so-called "translated"
instructions (e.g. STTR) at EL1 can cause EL0 watchpoints to fire
unexpectedly if kernel debugging is enabled. In such cases, the
hw_breakpoint logic will invoke the user overflow handler which will
typically raise a SIGTRAP back to the current task. This is futile when
returning back to the kernel because (a) the signal won't have been
delivered and (b) userspace can't handle the thing anyway.
Avoid invoking the user overflow handler for watchpoints triggered by
kernel uaccess routines, and instead single-step over the faulting
instruction as we would if no overflow handler had been installed.
(Fixes tag identifies the introduction of unprivileged memory accesses,
which exposed this latent bug in the hw_breakpoint code)
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: James Morse <james.morse@arm.com>
Fixes: 57f4959bad ("arm64: kernel: Add support for User Access Override")
Reported-by: Luis Machado <luis.machado@linaro.org>
Signed-off-by: Will Deacon <will@kernel.org>
When I squashed the 'allnoconfig' compiler warning about the
set_sve_default_vl() function being defined but not used in commit
1e570f512c ("arm64/sve: Eliminate data races on sve_default_vl"), I
accidentally broke the build for configs where ARM64_SVE is enabled, but
SYSCTL is not.
Fix this by only compiling the SVE sysctl support if both CONFIG_SVE=y
and CONFIG_SYSCTL=y.
Cc: Dave Martin <Dave.Martin@arm.com>
Reported-by: Qian Cai <cai@lca.pw>
Link: https://lore.kernel.org/r/20200616131808.GA1040@lca.pw
Signed-off-by: Will Deacon <will@kernel.org>
sve_default_vl can be modified via the /proc/sys/abi/sve_default_vl
sysctl concurrently with use, and modified concurrently by multiple
threads.
Adding a lock for this seems overkill, and I don't want to think any
more than necessary, so just define wrappers using READ_ONCE()/
WRITE_ONCE().
This will avoid the possibility of torn accesses and repeated loads
and stores.
There's no evidence yet that this is going wrong in practice: this
is just hygiene. For generic sysctl users, it would be better to
build this kind of thing into the sysctl common code somehow.
Reported-by: Will Deacon <will@kernel.org>
Signed-off-by: Dave Martin <Dave.Martin@arm.com>
Link: https://lore.kernel.org/r/1591808590-20210-3-git-send-email-Dave.Martin@arm.com
[will: move set_sve_default_vl() inside #ifdef to squash allnoconfig warning]
Signed-off-by: Will Deacon <will@kernel.org>
Pull arm64 fixes from Will Deacon:
"arm64 fixes that came in during the merge window.
There will probably be more to come, but it doesn't seem like it's
worth me sitting on these in the meantime.
- Fix SCS debug check to report max stack usage in bytes as advertised
- Fix typo: CONFIG_FTRACE_WITH_REGS => CONFIG_DYNAMIC_FTRACE_WITH_REGS
- Fix incorrect mask in HiSilicon L3C perf PMU driver
- Fix compat vDSO compilation under some toolchain configurations
- Fix false UBSAN warning from ACPI IORT parsing code
- Fix booting under bootloaders that ignore TEXT_OFFSET
- Annotate debug initcall function with '__init'"
* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
arm64: warn on incorrect placement of the kernel by the bootloader
arm64: acpi: fix UBSAN warning
arm64: vdso32: add CONFIG_THUMB2_COMPAT_VDSO
drivers/perf: hisi: Fix wrong value for all counters enable
arm64: ftrace: Change CONFIG_FTRACE_WITH_REGS to CONFIG_DYNAMIC_FTRACE_WITH_REGS
arm64: debug: mark a function as __init to save some memory
scs: Report SCS usage in bytes rather than number of entries
Commit cfa7ede20f ("arm64: set TEXT_OFFSET to 0x0 in preparation for
removing it entirely") results in boot failures when booting kernels that
are built without KASLR support on broken bootloaders that ignore the
TEXT_OFFSET value passed via the header, and use the default of 0x80000
instead.
To work around this, turn CONFIG_RELOCATABLE on by default, even if KASLR
itself (CONFIG_RANDOMIZE_BASE) is turned off, and require CONFIG_EXPERT
to be enabled to deviate from this. Then, emit a warning into the kernel
log if we are not booting via the EFI stub (which is permitted to deviate
from the placement restrictions) and the kernel base address is not placed
according to the rules as laid out in Documentation/arm64/booting.rst.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Link: https://lore.kernel.org/r/20200611124330.252163-1-ardb@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
Allow the compat vdso (32b) to be compiled as either THUMB2 (default) or
ARM.
For THUMB2, the register r7 is reserved for the frame pointer, but
code in arch/arm64/include/asm/vdso/compat_gettimeofday.h
uses r7. Explicitly set -fomit-frame-pointer, since unwinding through
interworked THUMB2 and ARM is unreliable anyways. See also how
CONFIG_UNWINDER_FRAME_POINTER cannot be selected for
CONFIG_THUMB2_KERNEL for ARCH=arm.
This also helps toolchains that differ in their implicit value if the
choice of -f{no-}omit-frame-pointer is left unspecified, to not error on
the use of r7.
2019 Q4 ARM AAPCS seeks to standardize the use of r11 as the reserved
frame pointer register, but no production compiler that can compile the
Linux kernel currently implements this. We're actively discussing such
a transition with ARM toolchain developers currently.
Reported-by: Luis Lozano <llozano@google.com>
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Tested-by: Manoj Gupta <manojgupta@google.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Stephen Boyd <swboyd@google.com>
Cc: Robin Murphy <robin.murphy@arm.com>
Cc: Dave Martin <Dave.Martin@arm.com>
Link: https://static.docs.arm.com/ihi0042/i/aapcs32.pdf
Link: https://bugs.chromium.org/p/chromium/issues/detail?id=1084372
Link: https://lore.kernel.org/r/20200608205711.109418-1-ndesaulniers@google.com
Signed-off-by: Will Deacon <will@kernel.org>
Currently, the log-level of show_stack() depends on a platform
realization. It creates situations where the headers are printed with
lower log level or higher than the stacktrace (depending on a platform or
user).
Furthermore, it forces the logic decision from user to an architecture
side. In result, some users as sysrq/kdb/etc are doing tricks with
temporary rising console_loglevel while printing their messages. And in
result it not only may print unwanted messages from other CPUs, but also
omit printing at all in the unlucky case where the printk() was deferred.
Introducing log-level parameter and KERN_UNSUPPRESSED [1] seems an easier
approach than introducing more printk buffers. Also, it will consolidate
printings with headers.
Introduce show_stack_loglvl(), that eventually will substitute
show_stack().
[1]: https://lore.kernel.org/lkml/20190528002412.1625-1-dima@arista.com/T/#u
Signed-off-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Will Deacon <will@kernel.org>
Link: http://lkml.kernel.org/r/20200418201944.482088-11-dima@arista.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Currently, the log-level of show_stack() depends on a platform
realization. It creates situations where the headers are printed with
lower log level or higher than the stacktrace (depending on a platform or
user).
Furthermore, it forces the logic decision from user to an architecture
side. In result, some users as sysrq/kdb/etc are doing tricks with
temporary rising console_loglevel while printing their messages. And in
result it not only may print unwanted messages from other CPUs, but also
omit printing at all in the unlucky case where the printk() was deferred.
Introducing log-level parameter and KERN_UNSUPPRESSED [1] seems an easier
approach than introducing more printk buffers. Also, it will consolidate
printings with headers.
Add log level argument to dump_backtrace() as a preparation for
introducing show_stack_loglvl().
[1]: https://lore.kernel.org/lkml/20190528002412.1625-1-dima@arista.com/T/#u
Signed-off-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Will Deacon <will@kernel.org>
Link: http://lkml.kernel.org/r/20200418201944.482088-10-dima@arista.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull networking updates from David Miller:
1) Allow setting bluetooth L2CAP modes via socket option, from Luiz
Augusto von Dentz.
2) Add GSO partial support to igc, from Sasha Neftin.
3) Several cleanups and improvements to r8169 from Heiner Kallweit.
4) Add IF_OPER_TESTING link state and use it when ethtool triggers a
device self-test. From Andrew Lunn.
5) Start moving away from custom driver versions, use the globally
defined kernel version instead, from Leon Romanovsky.
6) Support GRO vis gro_cells in DSA layer, from Alexander Lobakin.
7) Allow hard IRQ deferral during NAPI, from Eric Dumazet.
8) Add sriov and vf support to hinic, from Luo bin.
9) Support Media Redundancy Protocol (MRP) in the bridging code, from
Horatiu Vultur.
10) Support netmap in the nft_nat code, from Pablo Neira Ayuso.
11) Allow UDPv6 encapsulation of ESP in the ipsec code, from Sabrina
Dubroca. Also add ipv6 support for espintcp.
12) Lots of ReST conversions of the networking documentation, from Mauro
Carvalho Chehab.
13) Support configuration of ethtool rxnfc flows in bcmgenet driver,
from Doug Berger.
14) Allow to dump cgroup id and filter by it in inet_diag code, from
Dmitry Yakunin.
15) Add infrastructure to export netlink attribute policies to
userspace, from Johannes Berg.
16) Several optimizations to sch_fq scheduler, from Eric Dumazet.
17) Fallback to the default qdisc if qdisc init fails because otherwise
a packet scheduler init failure will make a device inoperative. From
Jesper Dangaard Brouer.
18) Several RISCV bpf jit optimizations, from Luke Nelson.
19) Correct the return type of the ->ndo_start_xmit() method in several
drivers, it's netdev_tx_t but many drivers were using
'int'. From Yunjian Wang.
20) Add an ethtool interface for PHY master/slave config, from Oleksij
Rempel.
21) Add BPF iterators, from Yonghang Song.
22) Add cable test infrastructure, including ethool interfaces, from
Andrew Lunn. Marvell PHY driver is the first to support this
facility.
23) Remove zero-length arrays all over, from Gustavo A. R. Silva.
24) Calculate and maintain an explicit frame size in XDP, from Jesper
Dangaard Brouer.
25) Add CAP_BPF, from Alexei Starovoitov.
26) Support terse dumps in the packet scheduler, from Vlad Buslov.
27) Support XDP_TX bulking in dpaa2 driver, from Ioana Ciornei.
28) Add devm_register_netdev(), from Bartosz Golaszewski.
29) Minimize qdisc resets, from Cong Wang.
30) Get rid of kernel_getsockopt and kernel_setsockopt in order to
eliminate set_fs/get_fs calls. From Christoph Hellwig.
* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (2517 commits)
selftests: net: ip_defrag: ignore EPERM
net_failover: fixed rollback in net_failover_open()
Revert "tipc: Fix potential tipc_aead refcnt leak in tipc_crypto_rcv"
Revert "tipc: Fix potential tipc_node refcnt leak in tipc_rcv"
vmxnet3: allow rx flow hash ops only when rss is enabled
hinic: add set_channels ethtool_ops support
selftests/bpf: Add a default $(CXX) value
tools/bpf: Don't use $(COMPILE.c)
bpf, selftests: Use bpf_probe_read_kernel
s390/bpf: Use bcr 0,%0 as tail call nop filler
s390/bpf: Maintain 8-byte stack alignment
selftests/bpf: Fix verifier test
selftests/bpf: Fix sample_cnt shared between two threads
bpf, selftests: Adapt cls_redirect to call csum_level helper
bpf: Add csum_level helper for fixing up csum levels
bpf: Fix up bpf_skb_adjust_room helper's skb csum setting
sfc: add missing annotation for efx_ef10_try_update_nic_stats_vf()
crypto/chtls: IPv6 support for inline TLS
Crypto/chcr: Fixes a coccinile check error
Crypto/chcr: Fixes compilations warnings
...
Pull kvm updates from Paolo Bonzini:
"ARM:
- Move the arch-specific code into arch/arm64/kvm
- Start the post-32bit cleanup
- Cherry-pick a few non-invasive pre-NV patches
x86:
- Rework of TLB flushing
- Rework of event injection, especially with respect to nested
virtualization
- Nested AMD event injection facelift, building on the rework of
generic code and fixing a lot of corner cases
- Nested AMD live migration support
- Optimization for TSC deadline MSR writes and IPIs
- Various cleanups
- Asynchronous page fault cleanups (from tglx, common topic branch
with tip tree)
- Interrupt-based delivery of asynchronous "page ready" events (host
side)
- Hyper-V MSRs and hypercalls for guest debugging
- VMX preemption timer fixes
s390:
- Cleanups
Generic:
- switch vCPU thread wakeup from swait to rcuwait
The other architectures, and the guest side of the asynchronous page
fault work, will come next week"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (256 commits)
KVM: selftests: fix rdtsc() for vmx_tsc_adjust_test
KVM: check userspace_addr for all memslots
KVM: selftests: update hyperv_cpuid with SynDBG tests
x86/kvm/hyper-v: Add support for synthetic debugger via hypercalls
x86/kvm/hyper-v: enable hypercalls regardless of hypercall page
x86/kvm/hyper-v: Add support for synthetic debugger interface
x86/hyper-v: Add synthetic debugger definitions
KVM: selftests: VMX preemption timer migration test
KVM: nVMX: Fix VMX preemption timer migration
x86/kvm/hyper-v: Explicitly align hcall param for kvm_hyperv_exit
KVM: x86/pmu: Support full width counting
KVM: x86/pmu: Tweak kvm_pmu_get_msr to pass 'struct msr_data' in
KVM: x86: announce KVM_FEATURE_ASYNC_PF_INT
KVM: x86: acknowledgment mechanism for async pf page ready notifications
KVM: x86: interrupt based APF 'page ready' event delivery
KVM: introduce kvm_read_guest_offset_cached()
KVM: rename kvm_arch_can_inject_async_page_present() to kvm_arch_can_dequeue_async_page_present()
KVM: x86: extend struct kvm_vcpu_pv_apf_data with token info
Revert "KVM: async_pf: Fix #DF due to inject "Page not Present" and "Page Ready" exceptions simultaneously"
KVM: VMX: Replace zero-length array with flexible-array
...
Pull ACPI updates from Rafael Wysocki:
"These update the ACPICA code in the kernel to upstream revision
20200430, fix several reference counting errors related to ACPI
tables, add _Exx / _Lxx support to the GED driver, add a new
acpi_evaluate_reg() helper, add new DPTF battery participant driver
and extend the DPFT power participant driver, improve the handling of
memory failures in the APEI code, add a blacklist entry to the
backlight driver, update the PMIC driver and the processor idle
driver, fix two kobject reference count leaks, and make a few janitory
changes.
Specifics:
- Update the ACPICA code in the kernel to upstream revision 20200430:
- Move acpi_gbl_next_cmd_num definition (Erik Kaneda).
- Ignore AE_ALREADY_EXISTS status in the disassembler when parsing
create operators (Erik Kaneda).
- Add status checks to the dispatcher (Erik Kaneda).
- Fix required parameters for _NIG and _NIH (Erik Kaneda).
- Make acpi_protocol_lengths static (Yue Haibing).
- Fix ACPI table reference counting errors in several places, mostly
in error code paths (Hanjun Guo).
- Extend the Generic Event Device (GED) driver to support _Exx and
_Lxx handler methods (Ard Biesheuvel).
- Add new acpi_evaluate_reg() helper and modify the ACPI PCI hotplug
code to use it (Hans de Goede).
- Add new DPTF battery participant driver and make the DPFT power
participant driver create more sysfs device attributes (Srinivas
Pandruvada).
- Improve the handling of memory failures in APEI (James Morse).
- Add new blacklist entry for Acer TravelMate 5735Z to the backlight
driver (Paul Menzel).
- Add i2c address for thermal control to the PMIC driver (Mauro
Carvalho Chehab).
- Allow the ACPI processor idle driver to work on platforms with only
one ACPI C-state present (Zhang Rui).
- Fix kobject reference count leaks in error code paths in two places
(Qiushi Wu).
- Delete unused proc filename macros and make some symbols static
(Pascal Terjan, Zheng Zengkai, Zou Wei)"
* tag 'acpi-5.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (32 commits)
ACPI: CPPC: Fix reference count leak in acpi_cppc_processor_probe()
ACPI: sysfs: Fix reference count leak in acpi_sysfs_add_hotplug_profile()
ACPI: GED: use correct trigger type field in _Exx / _Lxx handling
ACPI: DPTF: Add battery participant driver
ACPI: DPTF: Additional sysfs attributes for power participant driver
ACPI: video: Use native backlight on Acer TravelMate 5735Z
arm64: acpi: Make apei_claim_sea() synchronise with APEI's irq work
ACPI: APEI: Kick the memory_failure() queue for synchronous errors
mm/memory-failure: Add memory_failure_queue_kick()
ACPI / PMIC: Add i2c address for thermal control
ACPI: GED: add support for _Exx / _Lxx handler methods
ACPI: Delete unused proc filename macros
ACPI: hotplug: PCI: Use the new acpi_evaluate_reg() helper
ACPI: utils: Add acpi_evaluate_reg() helper
ACPI: debug: Make two functions static
ACPI: sleep: Put the FACS table after using it
ACPI: scan: Put SPCR and STAO table after using it
ACPI: EC: Put the ACPI table after using it
ACPI: APEI: Put the HEST table for error path
ACPI: APEI: Put the error record serialization table for error path
...
Pull arm64 updates from Will Deacon:
"A sizeable pile of arm64 updates for 5.8.
Summary below, but the big two features are support for Branch Target
Identification and Clang's Shadow Call stack. The latter is currently
arm64-only, but the high-level parts are all in core code so it could
easily be adopted by other architectures pending toolchain support
Branch Target Identification (BTI):
- Support for ARMv8.5-BTI in both user- and kernel-space. This allows
branch targets to limit the types of branch from which they can be
called and additionally prevents branching to arbitrary code,
although kernel support requires a very recent toolchain.
- Function annotation via SYM_FUNC_START() so that assembly functions
are wrapped with the relevant "landing pad" instructions.
- BPF and vDSO updates to use the new instructions.
- Addition of a new HWCAP and exposure of BTI capability to userspace
via ID register emulation, along with ELF loader support for the
BTI feature in .note.gnu.property.
- Non-critical fixes to CFI unwind annotations in the sigreturn
trampoline.
Shadow Call Stack (SCS):
- Support for Clang's Shadow Call Stack feature, which reserves
platform register x18 to point at a separate stack for each task
that holds only return addresses. This protects function return
control flow from buffer overruns on the main stack.
- Save/restore of x18 across problematic boundaries (user-mode,
hypervisor, EFI, suspend, etc).
- Core support for SCS, should other architectures want to use it
too.
- SCS overflow checking on context-switch as part of the existing
stack limit check if CONFIG_SCHED_STACK_END_CHECK=y.
CPU feature detection:
- Removed numerous "SANITY CHECK" errors when running on a system
with mismatched AArch32 support at EL1. This is primarily a concern
for KVM, which disabled support for 32-bit guests on such a system.
- Addition of new ID registers and fields as the architecture has
been extended.
Perf and PMU drivers:
- Minor fixes and cleanups to system PMU drivers.
Hardware errata:
- Unify KVM workarounds for VHE and nVHE configurations.
- Sort vendor errata entries in Kconfig.
Secure Monitor Call Calling Convention (SMCCC):
- Update to the latest specification from Arm (v1.2).
- Allow PSCI code to query the SMCCC version.
Software Delegated Exception Interface (SDEI):
- Unexport a bunch of unused symbols.
- Minor fixes to handling of firmware data.
Pointer authentication:
- Add support for dumping the kernel PAC mask in vmcoreinfo so that
the stack can be unwound by tools such as kdump.
- Simplification of key initialisation during CPU bringup.
BPF backend:
- Improve immediate generation for logical and add/sub instructions.
vDSO:
- Minor fixes to the linker flags for consistency with other
architectures and support for LLVM's unwinder.
- Clean up logic to initialise and map the vDSO into userspace.
ACPI:
- Work around for an ambiguity in the IORT specification relating to
the "num_ids" field.
- Support _DMA method for all named components rather than only PCIe
root complexes.
- Minor other IORT-related fixes.
Miscellaneous:
- Initialise debug traps early for KGDB and fix KDB cacheflushing
deadlock.
- Minor tweaks to early boot state (documentation update, set
TEXT_OFFSET to 0x0, increase alignment of PE/COFF sections).
- Refactoring and cleanup"
* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (148 commits)
KVM: arm64: Move __load_guest_stage2 to kvm_mmu.h
KVM: arm64: Check advertised Stage-2 page size capability
arm64/cpufeature: Add get_arm64_ftr_reg_nowarn()
ACPI/IORT: Remove the unused __get_pci_rid()
arm64/cpuinfo: Add ID_MMFR4_EL1 into the cpuinfo_arm64 context
arm64/cpufeature: Add remaining feature bits in ID_AA64PFR1 register
arm64/cpufeature: Add remaining feature bits in ID_AA64PFR0 register
arm64/cpufeature: Add remaining feature bits in ID_AA64ISAR0 register
arm64/cpufeature: Add remaining feature bits in ID_MMFR4 register
arm64/cpufeature: Add remaining feature bits in ID_PFR0 register
arm64/cpufeature: Introduce ID_MMFR5 CPU register
arm64/cpufeature: Introduce ID_DFR1 CPU register
arm64/cpufeature: Introduce ID_PFR2 CPU register
arm64/cpufeature: Make doublelock a signed feature in ID_AA64DFR0
arm64/cpufeature: Drop TraceFilt feature exposure from ID_DFR0 register
arm64/cpufeature: Add explicit ftr_id_isar0[] for ID_ISAR0 register
arm64: mm: Add asid_gen_match() helper
firmware: smccc: Fix missing prototype warning for arm_smccc_version_init
arm64: vdso: Fix CFI directives in sigreturn trampoline
arm64: vdso: Don't prefix sigreturn trampoline with a BTI C instruction
...
