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commit 8dfe804a4031ca6ba3a3efb2048534249b64f3a5 upstream.
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>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
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commit e575fb9e76c8e33440fb859572a8b7d430f053d6 upstream.
When I squashed the 'allnoconfig' compiler warning about the
set_sve_default_vl() function being defined but not used in commit
1e570f512cbd ("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>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
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commit 24ebec25fb270100e252b19c288e21bd7d8cc7f7 upstream.
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: 57f4959bad0a ("arm64: kernel: Add support for User Access Override")
Reported-by: Luis Machado <luis.machado@linaro.org>
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
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commit 579d1b3faa3735e781ff74aac0afd598515dbc63 upstream.
This patch fixes two issues present in the current function for encoding
arm64 logical immediates when using the 32-bit variants of instructions.
First, the code does not correctly reject an all-ones 32-bit immediate,
and returns an undefined instruction encoding.
Second, the code incorrectly rejects some 32-bit immediates that are
actually encodable as logical immediates. The root cause is that the code
uses a default mask of 64-bit all-ones, even for 32-bit immediates.
This causes an issue later on when the default mask is used to fill the
top bits of the immediate with ones, shown here:
/*
* Pattern: 0..01..10..01..1
*
* Fill the unused top bits with ones, and check if
* the result is a valid immediate (all ones with a
* contiguous ranges of zeroes).
*/
imm |= ~mask;
if (!range_of_ones(~imm))
return AARCH64_BREAK_FAULT;
To see the problem, consider an immediate of the form 0..01..10..01..1,
where the upper 32 bits are zero, such as 0x80000001. The code checks
if ~(imm | ~mask) contains a range of ones: the incorrect mask yields
1..10..01..10..0, which fails the check; the correct mask yields
0..01..10..0, which succeeds.
The fix for both issues is to generate a correct mask based on the
instruction immediate size, and use the mask to check for all-ones,
all-zeroes, and values wider than the mask.
Currently, arch/arm64/kvm/va_layout.c is the only user of this function,
which uses 64-bit immediates and therefore won't trigger these bugs.
We tested the new code against llvm-mc with all 1,302 encodable 32-bit
logical immediates and all 5,334 encodable 64-bit logical immediates.
Fixes: ef3935eeebff ("arm64: insn: Add encoder for bitwise operations using literals")
Suggested-by: Will Deacon <will@kernel.org>
Co-developed-by: Xi Wang <xi.wang@gmail.com>
Signed-off-by: Xi Wang <xi.wang@gmail.com>
Signed-off-by: Luke Nelson <luke.r.nels@gmail.com>
Reviewed-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20200508181547.24783-2-luke.r.nels@gmail.com
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
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commit 9d2d75ede59bc1edd8561f2ee9d4702a5ea0ae30 upstream.
Prior to commit 8eb7e28d4c642c31 ("arm64/mm: move runtime pgds to
rodata"), idmap_pgd_dir, tramp_pg_dir, reserved_ttbr0, swapper_pg_dir,
and init_pg_dir were contiguous at the end of the kernel image. The
maintenance at the end of __create_page_tables assumed these were
contiguous, and affected everything from the start of idmap_pg_dir
to the end of init_pg_dir.
That commit moved all but init_pg_dir into the .rodata section, with
other data placed between idmap_pg_dir and init_pg_dir, but did not
update the maintenance. Hence the maintenance is performed on much
more data than necessary (but as the bootloader previously made this
clean to the PoC there is no functional problem).
As we only alter idmap_pg_dir, and init_pg_dir, we only need to perform
maintenance for these. As the other dirs are in .rodata, the bootloader
will have initialised them as expected and cleaned them to the PoC. The
kernel will initialize them as necessary after enabling the MMU.
This patch reworks the maintenance to only cover the idmap_pg_dir and
init_pg_dir to avoid this unnecessary work.
Signed-off-by: Gavin Shan <gshan@redhat.com>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20200427235700.112220-1-gshan@redhat.com
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
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commit ec52c7134b1fcef0edfc56d55072fd4f261ef198 upstream.
If CONFIG_ARM64_SVE=n then we fail to report ID_AA64ZFR0_EL1 as 0 when
read by userspace, despite being required by the architecture. Although
this is theoretically a change in ABI, userspace will first check for
the presence of SVE via the HWCAP or the ID_AA64PFR0_EL1.SVE field
before probing the ID_AA64ZFR0_EL1 register. Given that these are
reported correctly for this configuration, we can safely tighten up the
current behaviour.
Ensure ID_AA64ZFR0_EL1 is treated as RAZ when CONFIG_ARM64_SVE=n.
Signed-off-by: Julien Grall <julien.grall@arm.com>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Dave Martin <dave.martin@arm.com>
Fixes: 06a916feca2b ("arm64: Expose SVE2 features for userspace")
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
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commit d51c214541c5154dda3037289ee895ea3ded5ebd upstream.
The second argument is the end "pointer", not the length.
Fixes: d28f6df1305a ("arm64/kexec: Add core kexec support")
Cc: <stable@vger.kernel.org> # 4.8.x-
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
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commit 27a22fbdeedd6c5c451cf5f830d51782bf50c3a2 upstream.
Clang reports a warning on the __tlbi(aside1is, 0) macro expansion since
the value size does not match the register size specified in the inline
asm. Construct the ASID value using the __TLBI_VADDR() macro.
Fixes: 222fc0c8503d ("arm64: compat: Workaround Neoverse-N1 #1542419 for compat user-space")
Reported-by: Nathan Chancellor <natechancellor@gmail.com>
Cc: James Morse <james.morse@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
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commit 222fc0c8503d98cec3cb2bac2780cdd21a6e31c0 upstream.
Compat user-space is unable to perform ICIMVAU instructions from
user-space. Instead it uses a compat-syscall. Add the workaround for
Neoverse-N1 #1542419 to this code path.
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
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commit ee9d90be9ddace01b7fb126567e4b539fbe1f82f upstream.
Systems affected by Neoverse-N1 #1542419 support DIC so do not need to
perform icache maintenance once new instructions are cleaned to the PoU.
For the errata workaround, the kernel hides DIC from user-space, so that
the unnecessary cache maintenance can be trapped by firmware.
To reduce the number of traps, produce a fake IminLine value based on
PAGE_SIZE.
Signed-off-by: James Morse <james.morse@arm.com>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
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commit 05460849c3b51180d5ada3373d0449aea19075e4 upstream.
Cores affected by Neoverse-N1 #1542419 could execute a stale instruction
when a branch is updated to point to freshly generated instructions.
To workaround this issue we need user-space to issue unnecessary
icache maintenance that we can trap. Start by hiding CTR_EL0.DIC.
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
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commit fc2266011accd5aeb8ebc335c381991f20e26e33 upstream.
For thumb instructions, call_undef_hook() in traps.c first reads a u16,
and if the u16 indicates a T32 instruction (u16 >= 0xe800), a second
u16 is read, which then makes up the the lower half-word of a T32
instruction. For T16 instructions, the second u16 is not read,
which makes the resulting u32 opcode always have the upper half set to
0.
However, having the upper half of instr_mask in the undef_hook set to 0
masks out the upper half of all thumb instructions - both T16 and T32.
This results in trapped T32 instructions with the lower half-word equal
to the T16 encoding of setend (b650) being matched, even though the upper
half-word is not 0000 and thus indicates a T32 opcode.
An example of such a T32 instruction is eaa0b650, which should raise a
SIGILL since T32 instructions with an eaa prefix are unallocated as per
Arm ARM, but instead works as a SETEND because the second half-word is set
to b650.
This patch fixes the issue by extending instr_mask to include the
upper u32 half, which will still match T16 instructions where the upper
half is 0, but not T32 instructions.
Fixes: 2d888f48e056 ("arm64: Emulate SETEND for AArch32 tasks")
Cc: <stable@vger.kernel.org> # 4.0.x-
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Fredrik Strupe <fredrik@strupe.net>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
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commit f50b7dacccbab2b9e3ef18f52a6dcc18ed2050b9 upstream.
On a system configured to trigger a crash_kexec() reboot, when only one CPU
is online and another CPU panics while starting-up, crash_smp_send_stop()
will fail to send any STOP message to the other already online core,
resulting in fail to freeze and registers not properly saved.
Moreover even if the proper messages are sent (case CPUs > 2)
it will similarly fail to account for the booting CPU when executing
the final stop wait-loop, so potentially resulting in some CPU not
been waited for shutdown before rebooting.
A tangible effect of this behaviour can be observed when, after a panic
with kexec enabled and loaded, on the following reboot triggered by kexec,
the cpu that could not be successfully stopped fails to come back online:
[ 362.291022] ------------[ cut here ]------------
[ 362.291525] kernel BUG at arch/arm64/kernel/cpufeature.c:886!
[ 362.292023] Internal error: Oops - BUG: 0 [#1] PREEMPT SMP
[ 362.292400] Modules linked in:
[ 362.292970] CPU: 3 PID: 0 Comm: swapper/3 Kdump: loaded Not tainted 5.6.0-rc4-00003-gc780b890948a #105
[ 362.293136] Hardware name: Foundation-v8A (DT)
[ 362.293382] pstate: 200001c5 (nzCv dAIF -PAN -UAO)
[ 362.294063] pc : has_cpuid_feature+0xf0/0x348
[ 362.294177] lr : verify_local_elf_hwcaps+0x84/0xe8
[ 362.294280] sp : ffff800011b1bf60
[ 362.294362] x29: ffff800011b1bf60 x28: 0000000000000000
[ 362.294534] x27: 0000000000000000 x26: 0000000000000000
[ 362.294631] x25: 0000000000000000 x24: ffff80001189a25c
[ 362.294718] x23: 0000000000000000 x22: 0000000000000000
[ 362.294803] x21: ffff8000114aa018 x20: ffff800011156a00
[ 362.294897] x19: ffff800010c944a0 x18: 0000000000000004
[ 362.294987] x17: 0000000000000000 x16: 0000000000000000
[ 362.295073] x15: 00004e53b831ae3c x14: 00004e53b831ae3c
[ 362.295165] x13: 0000000000000384 x12: 0000000000000000
[ 362.295251] x11: 0000000000000000 x10: 00400032b5503510
[ 362.295334] x9 : 0000000000000000 x8 : ffff800010c7e204
[ 362.295426] x7 : 00000000410fd0f0 x6 : 0000000000000001
[ 362.295508] x5 : 00000000410fd0f0 x4 : 0000000000000000
[ 362.295592] x3 : 0000000000000000 x2 : ffff8000100939d8
[ 362.295683] x1 : 0000000000180420 x0 : 0000000000180480
[ 362.296011] Call trace:
[ 362.296257] has_cpuid_feature+0xf0/0x348
[ 362.296350] verify_local_elf_hwcaps+0x84/0xe8
[ 362.296424] check_local_cpu_capabilities+0x44/0x128
[ 362.296497] secondary_start_kernel+0xf4/0x188
[ 362.296998] Code: 52805001 72a00301 6b01001f 54000ec0 (d4210000)
[ 362.298652] SMP: stopping secondary CPUs
[ 362.300615] Starting crashdump kernel...
[ 362.301168] Bye!
[ 0.000000] Booting Linux on physical CPU 0x0000000003 [0x410fd0f0]
[ 0.000000] Linux version 5.6.0-rc4-00003-gc780b890948a (crimar01@e120937-lin) (gcc version 8.3.0 (GNU Toolchain for the A-profile Architecture 8.3-2019.03 (arm-rel-8.36))) #105 SMP PREEMPT Fri Mar 6 17:00:42 GMT 2020
[ 0.000000] Machine model: Foundation-v8A
[ 0.000000] earlycon: pl11 at MMIO 0x000000001c090000 (options '')
[ 0.000000] printk: bootconsole [pl11] enabled
.....
[ 0.138024] rcu: Hierarchical SRCU implementation.
[ 0.153472] its@2f020000: unable to locate ITS domain
[ 0.154078] its@2f020000: Unable to locate ITS domain
[ 0.157541] EFI services will not be available.
[ 0.175395] smp: Bringing up secondary CPUs ...
[ 0.209182] psci: failed to boot CPU1 (-22)
[ 0.209377] CPU1: failed to boot: -22
[ 0.274598] Detected PIPT I-cache on CPU2
[ 0.278707] GICv3: CPU2: found redistributor 1 region 0:0x000000002f120000
[ 0.285212] CPU2: Booted secondary processor 0x0000000001 [0x410fd0f0]
[ 0.369053] Detected PIPT I-cache on CPU3
[ 0.372947] GICv3: CPU3: found redistributor 2 region 0:0x000000002f140000
[ 0.378664] CPU3: Booted secondary processor 0x0000000002 [0x410fd0f0]
[ 0.401707] smp: Brought up 1 node, 3 CPUs
[ 0.404057] SMP: Total of 3 processors activated.
Make crash_smp_send_stop() account also for the online status of the
calling CPU while evaluating how many CPUs are effectively online: this way
the right number of STOPs is sent and all other stopped-cores's registers
are properly saved.
Fixes: 78fd584cdec05 ("arm64: kdump: implement machine_crash_shutdown()")
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
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commit d0bab0c39e32d39a8c5cddca72e5b4a3059fe050 upstream.
On a system with only one CPU online, when another one CPU panics while
starting-up, smp_send_stop() will fail to send any STOP message to the
other already online core, resulting in a system still responsive and
alive at the end of the panic procedure.
[ 186.700083] CPU3: shutdown
[ 187.075462] CPU2: shutdown
[ 187.162869] CPU1: shutdown
[ 188.689998] ------------[ cut here ]------------
[ 188.691645] kernel BUG at arch/arm64/kernel/cpufeature.c:886!
[ 188.692079] Internal error: Oops - BUG: 0 [#1] PREEMPT SMP
[ 188.692444] Modules linked in:
[ 188.693031] CPU: 3 PID: 0 Comm: swapper/3 Not tainted 5.6.0-rc4-00001-g338d25c35a98 #104
[ 188.693175] Hardware name: Foundation-v8A (DT)
[ 188.693492] pstate: 200001c5 (nzCv dAIF -PAN -UAO)
[ 188.694183] pc : has_cpuid_feature+0xf0/0x348
[ 188.694311] lr : verify_local_elf_hwcaps+0x84/0xe8
[ 188.694410] sp : ffff800011b1bf60
[ 188.694536] x29: ffff800011b1bf60 x28: 0000000000000000
[ 188.694707] x27: 0000000000000000 x26: 0000000000000000
[ 188.694801] x25: 0000000000000000 x24: ffff80001189a25c
[ 188.694905] x23: 0000000000000000 x22: 0000000000000000
[ 188.694996] x21: ffff8000114aa018 x20: ffff800011156a38
[ 188.695089] x19: ffff800010c944a0 x18: 0000000000000004
[ 188.695187] x17: 0000000000000000 x16: 0000000000000000
[ 188.695280] x15: 0000249dbde5431e x14: 0262cbe497efa1fa
[ 188.695371] x13: 0000000000000002 x12: 0000000000002592
[ 188.695472] x11: 0000000000000080 x10: 00400032b5503510
[ 188.695572] x9 : 0000000000000000 x8 : ffff800010c80204
[ 188.695659] x7 : 00000000410fd0f0 x6 : 0000000000000001
[ 188.695750] x5 : 00000000410fd0f0 x4 : 0000000000000000
[ 188.695836] x3 : 0000000000000000 x2 : ffff8000100939d8
[ 188.695919] x1 : 0000000000180420 x0 : 0000000000180480
[ 188.696253] Call trace:
[ 188.696410] has_cpuid_feature+0xf0/0x348
[ 188.696504] verify_local_elf_hwcaps+0x84/0xe8
[ 188.696591] check_local_cpu_capabilities+0x44/0x128
[ 188.696666] secondary_start_kernel+0xf4/0x188
[ 188.697150] Code: 52805001 72a00301 6b01001f 54000ec0 (d4210000)
[ 188.698639] ---[ end trace 3f12ca47652f7b72 ]---
[ 188.699160] Kernel panic - not syncing: Attempted to kill the idle task!
[ 188.699546] Kernel Offset: disabled
[ 188.699828] CPU features: 0x00004,20c02008
[ 188.700012] Memory Limit: none
[ 188.700538] ---[ end Kernel panic - not syncing: Attempted to kill the idle task! ]---
[root@arch ~]# echo Helo
Helo
[root@arch ~]# cat /proc/cpuinfo | grep proce
processor : 0
Make smp_send_stop() account also for the online status of the calling CPU
while evaluating how many CPUs are effectively online: this way, the right
number of STOPs is sent, so enforcing a proper freeze of the system at the
end of panic even under the above conditions.
Fixes: 08e875c16a16c ("arm64: SMP support")
Reported-by: Dave Martin <Dave.Martin@arm.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
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commit 52f73c383b2418f2d31b798e765ae7d596c35021 upstream.
We detect the absence of FP/SIMD after an incapable CPU is brought up,
and by then we have kernel threads running already with TIF_FOREIGN_FPSTATE set
which could be set for early userspace applications (e.g, modprobe triggered
from initramfs) and init. This could cause the applications to loop forever in
do_nofity_resume() as we never clear the TIF flag, once we now know that
we don't support FP.
Fix this by making sure that we clear the TIF_FOREIGN_FPSTATE flag
for tasks which may have them set, as we would have done in the normal
case, but avoiding touching the hardware state (since we don't support any).
Also to make sure we handle the cases seemlessly we categorise the
helper functions to two :
1) Helpers for common core code, which calls into take appropriate
actions without knowing the current FPSIMD state of the CPU/task.
e.g fpsimd_restore_current_state(), fpsimd_flush_task_state(),
fpsimd_save_and_flush_cpu_state().
We bail out early for these functions, taking any appropriate actions
(e.g, clearing the TIF flag) where necessary to hide the handling
from core code.
2) Helpers used when the presence of FP/SIMD is apparent.
i.e, save/restore the FP/SIMD register state, modify the CPU/task
FP/SIMD state.
e.g,
fpsimd_save(), task_fpsimd_load() - save/restore task FP/SIMD registers
fpsimd_bind_task_to_cpu() \
- Update the "state" metadata for CPU/task.
fpsimd_bind_state_to_cpu() /
fpsimd_update_current_state() - Update the fp/simd state for the current
task from memory.
These must not be called in the absence of FP/SIMD. Put in a WARNING
to make sure they are not invoked in the absence of FP/SIMD.
KVM also uses the TIF_FOREIGN_FPSTATE flag to manage the FP/SIMD state
on the CPU. However, without FP/SIMD support we trap all accesses and
inject undefined instruction. Thus we should never "load" guest state.
Add a sanity check to make sure this is valid.
Fixes: 82e0191a1aa11abf ("arm64: Support systems without FP/ASIMD")
Cc: Will Deacon <will@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
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commit 6dcdefcde413c1068b394eeabdfdf6a85213ebe2 upstream.
When the kernel is compiled with CONFIG_KERNEL_MODE_NEON, some part of
the kernel may be able to use FPSIMD/SVE. This is for instance the case
for crypto code.
Any use of FPSIMD/SVE in the kernel are clearly marked by using the
function kernel_neon_{begin, end}. Furthermore, this can only be used
when may_use_simd() returns true.
The current implementation of may_use_simd() allows softirq to use
FPSIMD/SVE unless it is currently in use (i.e kernel_neon_busy is true).
When in use, softirqs usually fall back to a software method.
At the moment, as a softirq may use FPSIMD/SVE, softirqs are disabled
when touching the FPSIMD/SVE context. This has the drawback to disable
all softirqs even if they are not using FPSIMD/SVE.
Since a softirq is supposed to check may_use_simd() anyway before
attempting to use FPSIMD/SVE, there is limited reason to keep softirq
disabled when touching the FPSIMD/SVE context. Instead, we can simply
disable preemption and mark the FPSIMD/SVE context as in use by setting
CPU's fpsimd_context_busy flag.
Two new helpers {get, put}_cpu_fpsimd_context are introduced to mark
the area using FPSIMD/SVE context and they are used to replace
local_bh_{disable, enable}. The functions kernel_neon_{begin, end} are
also re-implemented to use the new helpers.
Additionally, double-underscored versions of the helpers are provided to
called when preemption is already disabled. These are only relevant on
paths where irqs are disabled anyway, so they are not needed for
correctness in the current code. Let's use them anyway though: this
marks critical sections clearly and will help to avoid mistakes during
future maintenance.
The change has been benchmarked on Linux 5.1-rc4 with defconfig.
On Juno2:
* hackbench 100 process 1000 (10 times)
* .7% quicker
On ThunderX 2:
* hackbench 1000 process 1000 (20 times)
* 3.4% quicker
Reviewed-by: Dave Martin <dave.martin@arm.com>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Julien Grall <julien.grall@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
|
|
commit 54b8c7cbc57c1ce21f4e35101f2609092c4af49a upstream.
The only external user of fpsimd_save() and fpsimd_flush_cpu_state() is
the KVM FPSIMD code.
A following patch will introduce a mechanism to acquire owernship of the
FPSIMD/SVE context for performing context management operations. Rather
than having to export the new helpers to get/put the context, we can just
introduce a new function to combine fpsimd_save() and
fpsimd_flush_cpu_state().
This has also the advantage to remove any external call of fpsimd_save()
and fpsimd_flush_cpu_state(), so they can be turned static.
Lastly, the new function can also be used in the PM notifier.
Reviewed-by: Dave Martin <Dave.Martin@arm.com>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Julien Grall <julien.grall@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
|
|
commit c9d66999f064947e6b577ceacc1eb2fbca6a8d3c upstream.
When fp/simd is not supported on the system, fail the operations
of FP/SIMD regsets.
Fixes: 82e0191a1aa11abf ("arm64: Support systems without FP/ASIMD")
Cc: Will Deacon <will@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
|
|
commit 7559950aef1ab8792c50797c6c5c7c5150a02460 upstream.
We set the compat_elf_hwcap bits unconditionally on arm64 to
include the VFP and NEON support. However, the FP/SIMD unit
is optional on Arm v8 and thus could be missing. We already
handle this properly in the kernel, but still advertise to
the COMPAT applications that the VFP is available. Fix this
to make sure we only advertise when we really have them.
Fixes: 82e0191a1aa11abf ("arm64: Support systems without FP/ASIMD")
Cc: Will Deacon <will@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
|
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commit 449443c03d8cfdacf7313e17779a2594ebf87e6d upstream.
The NO_FPSIMD capability is defined with scope SYSTEM, which implies
that the "absence" of FP/SIMD on at least one CPU is detected only
after all the SMP CPUs are brought up. However, we use the status
of this capability for every context switch. So, let us change
the scope to LOCAL_CPU to allow the detection of this capability
as and when the first CPU without FP is brought up.
Also, the current type allows hotplugged CPU to be brought up without
FP/SIMD when all the current CPUs have FP/SIMD and we have the userspace
up. Fix both of these issues by changing the capability to
BOOT_RESTRICTED_LOCAL_CPU_FEATURE.
Fixes: 82e0191a1aa11abf ("arm64: Support systems without FP/ASIMD")
Cc: Will Deacon <will@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
|
|
commit e533dbe9dcb199bb637a2c465f3a6e70564994fe upstream.
Since commit:
d44f1b8dd7e66d80 ("arm64: KVM/mm: Move SEA handling behind a single 'claim' interface")
... the top-level APEI SEA handler has the shape:
1. current_flags = arch_local_save_flags()
2. local_daif_restore(DAIF_ERRCTX)
3. <GHES handler>
4. local_daif_restore(current_flags)
However, since commit:
4a503217ce37e1f4 ("arm64: irqflags: Use ICC_PMR_EL1 for interrupt masking")
... when pseudo-NMIs (pNMIs) are in use, arch_local_save_flags() will save
the PMR value rather than the DAIF flags.
The combination of these two commits means that the APEI SEA handler will
erroneously attempt to restore the PMR value into DAIF. Fix this by
factoring local_daif_save_flags() out of local_daif_save(), so that we
can consistently save DAIF in step #1, regardless of whether pNMIs are in
use.
Both commits were introduced concurrently in v5.0.
Cc: <stable@vger.kernel.org>
Fixes: 4a503217ce37e1f4 ("arm64: irqflags: Use ICC_PMR_EL1 for interrupt masking")
Fixes: d44f1b8dd7e66d80 ("arm64: KVM/mm: Move SEA handling behind a single 'claim' interface")
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: James Morse <james.morse@arm.com>
Cc: Julien Thierry <julien.thierry.kdev@gmail.com>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
|
|
commit fca3d33d8ad61eb53eca3ee4cac476d1e31b9008 upstream.
When all CPUs in the system implement the SSBS extension, the SSBS field
in PSTATE is the definitive indication of the mitigation state. Further,
when the CPUs implement the SSBS manipulation instructions (advertised
to userspace via an HWCAP), EL0 can toggle the SSBS field directly and
so we cannot rely on any shadow state such as TIF_SSBD at all.
Avoid forcing the SSBS field in context-switch on such a system, and
simply rely on the PSTATE register instead.
Cc: <stable@vger.kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Srinivas Ramana <sramana@codeaurora.org>
Fixes: cbdf8a189a66 ("arm64: Force SSBS on context switch")
Reviewed-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
|
|
commit aa638cfe3e7358122a15cb1d295b622aae69e006 upstream.
HiSilicon Taishan v110 CPUs didn't implement CSV2 field of the
ID_AA64PFR0_EL1, but spectre-v2 is mitigated by hardware, so
whitelist the MIDR in the safe list.
Signed-off-by: Wei Li <liwei391@huawei.com>
[hanjun: re-write the commit log]
Signed-off-by: Hanjun Guo <guohanjun@huawei.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
|
|
commit bfcef4ab1d7ee8921bc322109b1692036cc6cbe0 upstream.
In cases like suspend-to-disk and suspend-to-ram, a large number of CPU
cores need to be shut down. At present, the CPU hotplug operation is
serialised, and the CPU cores can only be shut down one by one. In this
process, if PSCI affinity_info() does not return LEVEL_OFF quickly,
cpu_psci_cpu_kill() needs to wait for 10ms. If hundreds of CPU cores
need to be shut down, it will take a long time.
Normally, there is no need to wait 10ms in cpu_psci_cpu_kill(). So
change the wait interval from 10 ms to max 1 ms and use usleep_range()
instead of msleep() for more accurate timer.
In addition, reducing the time interval will increase the messages
output, so remove the "Retry ..." message, instead, track time and
output to the the sucessful message.
Signed-off-by: Yunfeng Ye <yeyunfeng@huawei.com>
Reviewed-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
|
|
commit 7a292b6c7c9c35afee01ce3b2248f705869d0ff1 upstream.
Commit 73f381660959 ("arm64: Advertise mitigation of Spectre-v2, or lack
thereof") renamed the caller of the install_bp_hardening_cb() function
but forgot to update a comment, which can be confusing when trying to
follow the code flow.
Fixes: 73f381660959 ("arm64: Advertise mitigation of Spectre-v2, or lack thereof")
Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
|
|
commit 1cf45b8fdbb87040e1d1bd793891089f4678aa41 upstream.
The Broadcom Brahma-B53 core is susceptible to the issue described by
ARM64_ERRATUM_843419 so this commit enables the workaround to be applied
when executing on that core.
Since there are now multiple entries to match, we must convert the
existing ARM64_ERRATUM_843419 into an erratum list and use
cpucap_multi_entry_cap_matches to match our entries.
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
|
|
commit e059770cb1cdfbcbe3f1748f76005861cc79dd1a upstream.
Add the Brahma-B53 CPU (all versions) to the whitelists of CPUs for the
SSB and spectre v2 mitigations.
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
|
|
commit bfc97f9f199cb041cf897af3af096540948cc705 upstream.
The Broadcom Brahma-B53 core is susceptible to the issue described by
ARM64_ERRATUM_845719 so this commit enables the workaround to be applied
when executing on that core.
Since there are now multiple entries to match, we must convert the
existing ARM64_ERRATUM_845719 into an erratum list.
Signed-off-by: Doug Berger <opendmb@gmail.com>
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
|
|
commit 36c602dcdd872e9f9b91aae5266b6d7d72b69b96 upstream.
The Kryo cores share errata 1009 with Falkor, so add their model
definitions and enable it for them as well.
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
[will: Update entry in silicon-errata.rst]
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
|
|
commit d4af3c4b81f4cd5662baa6f1492f998d89783318 upstream.
With the introduction of 'cce360b54ce6 ("arm64: capabilities: Filter the
entries based on a given mask")' the Qualcomm Falkor/Kryo errata 1003 is
no long applied.
The result of not applying errata 1003 is that MSM8996 runs into various
RCU stalls and fails to boot most of the times.
Give 1003 a "type" to ensure they are not filtered out in
update_cpu_capabilities().
Fixes: cce360b54ce6 ("arm64: capabilities: Filter the entries based on a given mask")
Cc: stable@vger.kernel.org
Reported-by: Mark Brown <broonie@kernel.org>
Suggested-by: Will Deacon <will@kernel.org>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
|
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commit 3e7c93bd04edfb0cae7dad1215544c9350254b8f upstream.
There are no return value checking when using kzalloc() and kcalloc() for
memory allocation. so add it.
Signed-off-by: Yunfeng Ye <yeyunfeng@huawei.com>
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
|
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commit dd8a1f13488438c6c220b7cafa500baaf21a6e53 upstream.
CPUs affected by Neoverse-N1 #1542419 may execute a stale instruction if
it was recently modified. The affected sequence requires freshly written
instructions to be executable before a branch to them is updated.
There are very few places in the kernel that modify executable text,
all but one come with sufficient synchronisation:
* The module loader's flush_module_icache() calls flush_icache_range(),
which does a kick_all_cpus_sync()
* bpf_int_jit_compile() calls flush_icache_range().
* Kprobes calls aarch64_insn_patch_text(), which does its work in
stop_machine().
* static keys and ftrace both patch between nops and branches to
existing kernel code (not generated code).
The affected sequence is the interaction between ftrace and modules.
The module PLT is cleaned using __flush_icache_range() as the trampoline
shouldn't be executable until we update the branch to it.
Drop the double-underscore so that this path runs kick_all_cpus_sync()
too.
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
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commit f46f27a576cc3b1e3d45ea50bc06287aa46b04b2 upstream.
Commit bd82d4bd2188 ("arm64: Fix incorrect irqflag restore for priority
masking") added a macro to the entry.S call paths that leave the
PSTATE.I bit set. This tells the pPNMI masking logic that interrupts
are masked by the CPU, not by the PMR. This value is read back by
local_daif_save().
Commit bd82d4bd2188 added this call to el0_svc, as el0_svc_handler
is called with interrupts masked. el0_svc_compat was missed, but should
be covered in the same way as both of these paths end up in
el0_svc_common(), which expects to unmask interrupts.
Fixes: bd82d4bd2188 ("arm64: Fix incorrect irqflag restore for priority masking")
Signed-off-by: James Morse <james.morse@arm.com>
Cc: Julien Thierry <julien.thierry.kdev@gmail.com>
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
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commit 4585fc59c0e813188d6a4c5de1f6976fce461fc2 upstream.
The system which has SVE feature crashed because of
the memory pointed by task->thread.sve_state was destroyed
by someone.
That is because sve_state is freed while the forking the
child process. The child process has the pointer of sve_state
which is same as the parent's because the child's task_struct
is copied from the parent's one. If the copy_process()
fails as an error on somewhere, for example, copy_creds(),
then the sve_state is freed even if the parent is alive.
The flow is as follows.
copy_process
p = dup_task_struct
=> arch_dup_task_struct
*dst = *src; // copy the entire region.
:
retval = copy_creds
if (retval < 0)
goto bad_fork_free;
:
bad_fork_free:
...
delayed_free_task(p);
=> free_task
=> arch_release_task_struct
=> fpsimd_release_task
=> __sve_free
=> kfree(task->thread.sve_state);
// free the parent's sve_state
Move child's sve_state = NULL and clearing TIF_SVE flag
to arch_dup_task_struct() so that the child doesn't free the
parent's one.
There is no need to wait until copy_process() to clear TIF_SVE for
dst, because the thread flags for dst are initialized already by
copying the src task_struct.
This change simplifies the code, so get rid of comments that are no
longer needed.
As a note, arm64 used to have thread_info on the stack. So it
would not be possible to clear TIF_SVE until the stack is initialized.
From commit c02433dd6de3 ("arm64: split thread_info from task stack"),
the thread_info is part of the task, so it should be valid to modify
the flag from arch_dup_task_struct().
Cc: stable@vger.kernel.org # 4.15.x-
Fixes: bc0ee4760364 ("arm64/sve: Core task context handling")
Signed-off-by: Masayoshi Mizuma <m.mizuma@jp.fujitsu.com>
Reported-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Suggested-by: Dave Martin <Dave.Martin@arm.com>
Reviewed-by: Dave Martin <Dave.Martin@arm.com>
Tested-by: Julien Grall <julien.grall@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
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commit 98dc19902a0b2e5348e43d6a2c39a0a7d0fc639e upstream.
ACPI 6.3 adds a thread flag to represent if a CPU/PE is
actually a thread. Given that the MPIDR_MT bit may not
represent this information consistently on homogeneous machines
we should prefer the PPTT flag if its available.
Signed-off-by: Jeremy Linton <jeremy.linton@arm.com>
Reviewed-by: Sudeep Holla <sudeep.holla@arm.com>
Reviewed-by: Robert Richter <rrichter@marvell.com>
[will: made acpi_cpu_is_threaded() return 'bool']
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
|
|
[ Upstream commit 2671828c3ff4ffadf777f793a1f3232d6e51394a ]
When taking an SError or Debug exception from EL0, we run the C
handler for these exceptions before updating the context tracking
code and unmasking lower priority interrupts.
When booting with nohz_full lockdep tells us we got this wrong:
| =============================
| WARNING: suspicious RCU usage
| 5.3.0-rc2-00010-gb4b5e9dcb11b-dirty #11271 Not tainted
| -----------------------------
| include/linux/rcupdate.h:643 rcu_read_unlock() used illegally wh!
|
| other info that might help us debug this:
|
|
| RCU used illegally from idle CPU!
| rcu_scheduler_active = 2, debug_locks = 1
| RCU used illegally from extended quiescent state!
| 1 lock held by a.out/432:
| #0: 00000000c7a79515 (rcu_read_lock){....}, at: brk_handler+0x00
|
| stack backtrace:
| CPU: 1 PID: 432 Comm: a.out Not tainted 5.3.0-rc2-00010-gb4b5e9d1
| Hardware name: ARM LTD ARM Juno Development Platform/ARM Juno De8
| Call trace:
| dump_backtrace+0x0/0x140
| show_stack+0x14/0x20
| dump_stack+0xbc/0x104
| lockdep_rcu_suspicious+0xf8/0x108
| brk_handler+0x164/0x1b0
| do_debug_exception+0x11c/0x278
| el0_dbg+0x14/0x20
Moving the ct_user_exit calls to be before do_debug_exception() means
they are also before trace_hardirqs_off() has been updated. Add a new
ct_user_exit_irqoff macro to avoid the context-tracking code using
irqsave/restore before we've updated trace_hardirqs_off(). To be
consistent, do this everywhere.
The C helper is called enter_from_user_mode() to match x86 in the hope
we can merge them into kernel/context_tracking.c later.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Fixes: 6c81fe7925cc4c42 ("arm64: enable context tracking")
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
|
|
[ Upstream commit 90776dd1c427cbb4d381aa4b13338f1fb1d20f5e ]
It seems that LLVM's linker does not correctly handle variable assignments
involving section positions that are updated during the SECTIONS
parsing. Commit aa69fb62bea1 ("arm64/efi: Mark __efistub_stext_offset as
an absolute symbol explicitly") ran into this too, but found a different
workaround.
However, this was not enough, as other variables were also miscalculated
which manifested as boot failures under UEFI where __efistub__end was
not taking the correct _end value (they should be the same):
$ ld.lld -EL -maarch64elf --no-undefined -X -shared \
-Bsymbolic -z notext -z norelro --no-apply-dynamic-relocs \
-o vmlinux.lld -T poc.lds --whole-archive vmlinux.o && \
readelf -Ws vmlinux.lld | egrep '\b(__efistub_|)_end\b'
368272: ffff000002218000 0 NOTYPE LOCAL HIDDEN 38 __efistub__end
368322: ffff000012318000 0 NOTYPE GLOBAL DEFAULT 38 _end
$ aarch64-linux-gnu-ld.bfd -EL -maarch64elf --no-undefined -X -shared \
-Bsymbolic -z notext -z norelro --no-apply-dynamic-relocs \
-o vmlinux.bfd -T poc.lds --whole-archive vmlinux.o && \
readelf -Ws vmlinux.bfd | egrep '\b(__efistub_|)_end\b'
338124: ffff000012318000 0 NOTYPE LOCAL DEFAULT ABS __efistub__end
383812: ffff000012318000 0 NOTYPE GLOBAL DEFAULT 15325 _end
To work around this, all of the __efistub_-prefixed variable assignments
need to be moved after the linker script's SECTIONS entry. As it turns
out, this also solves the problem fixed in commit aa69fb62bea1, so those
changes are reverted here.
Link: https://github.com/ClangBuiltLinux/linux/issues/634
Link: https://bugs.llvm.org/show_bug.cgi?id=42990
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
|
|
[ Upstream commit b99286b088ea843b935dcfb29f187697359fe5cd ]
The commit d5370f754875 ("arm64: prefetch: add alternative pattern for
CPUs without a prefetcher") introduced MIDR_IS_CPU_MODEL_RANGE() to be
used in has_no_hw_prefetch() with rv_min=0 which generates a compilation
warning from GCC,
In file included from ./arch/arm64/include/asm/cache.h:8,
from ./include/linux/cache.h:6,
from ./include/linux/printk.h:9,
from ./include/linux/kernel.h:15,
from ./include/linux/cpumask.h:10,
from arch/arm64/kernel/cpufeature.c:11:
arch/arm64/kernel/cpufeature.c: In function 'has_no_hw_prefetch':
./arch/arm64/include/asm/cputype.h:59:26: warning: comparison of
unsigned expression >= 0 is always true [-Wtype-limits]
_model == (model) && rv >= (rv_min) && rv <= (rv_max); \
^~
arch/arm64/kernel/cpufeature.c:889:9: note: in expansion of macro
'MIDR_IS_CPU_MODEL_RANGE'
return MIDR_IS_CPU_MODEL_RANGE(midr, MIDR_THUNDERX,
^~~~~~~~~~~~~~~~~~~~~~~
Fix it by converting MIDR_IS_CPU_MODEL_RANGE to a static inline
function.
Signed-off-by: Qian Cai <cai@lca.pw>
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
|
|
[ Upstream commit 5717fe5ab38f9ccb32718bcb03bea68409c9cce4 ]
If a CPU doesn't support the page size for which the kernel is
configured, then we will complain and refuse to bring it online. For
secondary CPUs (and the boot CPU on a system booting with EFI), we will
also print an error identifying the mismatch.
Consequently, the only time that the cpufeature code can detect a
granule size mismatch is for a granule other than the one that is
currently being used. Although we would rather such systems didn't
exist, we've unfortunately lost that battle and Kevin reports that
on his amlogic S922X (odroid-n2 board) we end up warning and taining
with defconfig because 16k pages are not supported by all of the CPUs.
In such a situation, we don't actually care about the feature mismatch,
particularly now that KVM only exposes the sanitised view of the CPU
registers (commit 93390c0a1b20 - "arm64: KVM: Hide unsupported AArch64
CPU features from guests"). Treat the granule fields as non-strict and
let Kevin run without a tainted kernel.
Cc: Marc Zyngier <maz@kernel.org>
Reported-by: Kevin Hilman <khilman@baylibre.com>
Tested-by: Kevin Hilman <khilman@baylibre.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
[catalin.marinas@arm.com: changelog updated with KVM sanitised regs commit]
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
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[ Upstream commit b3980e48528c4d2a9e70b145a5bba328b73a0f93 ]
kprobes manipulates the interrupted PSTATE for single step, and
doesn't restore it. Thus, if we put a kprobe where the pstate.D
(debug) masked, the mask will be cleared after the kprobe hits.
Moreover, in the most complicated case, this can lead a kernel
crash with below message when a nested kprobe hits.
[ 152.118921] Unexpected kernel single-step exception at EL1
When the 1st kprobe hits, do_debug_exception() will be called.
At this point, debug exception (= pstate.D) must be masked (=1).
But if another kprobes hits before single-step of the first kprobe
(e.g. inside user pre_handler), it unmask the debug exception
(pstate.D = 0) and return.
Then, when the 1st kprobe setting up single-step, it saves current
DAIF, mask DAIF, enable single-step, and restore DAIF.
However, since "D" flag in DAIF is cleared by the 2nd kprobe, the
single-step exception happens soon after restoring DAIF.
This has been introduced by commit 7419333fa15e ("arm64: kprobe:
Always clear pstate.D in breakpoint exception handler")
To solve this issue, this stores all DAIF bits and restore it
after single stepping.
Reported-by: Naresh Kamboju <naresh.kamboju@linaro.org>
Fixes: 7419333fa15e ("arm64: kprobe: Always clear pstate.D in breakpoint exception handler")
Reviewed-by: James Morse <james.morse@arm.com>
Tested-by: James Morse <james.morse@arm.com>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
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[ Upstream commit ee07b93e7721ccd5d5b9fa6f0c10cb3fe2f1f4f9 ]
Prohibit probing on return_address() and subroutines which
is called from return_address(), since the it is invoked from
trace_hardirqs_off() which is also kprobe blacklisted.
Reported-by: Naresh Kamboju <naresh.kamboju@linaro.org>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
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commit b6143d10d23ebb4a77af311e8b8b7f019d0163e6 upstream.
The initial support for dynamic ftrace trampolines in modules made use
of an indirect branch which loaded its target from the beginning of
a special section (e71a4e1bebaf7 ("arm64: ftrace: add support for far
branches to dynamic ftrace")). Since no instructions were being patched,
no cache maintenance was needed. However, later in be0f272bfc83 ("arm64:
ftrace: emit ftrace-mod.o contents through code") this code was reworked
to output the trampoline instructions directly into the PLT entry but,
unfortunately, the necessary cache maintenance was overlooked.
Add a call to __flush_icache_range() after writing the new trampoline
instructions but before patching in the branch to the trampoline.
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: James Morse <james.morse@arm.com>
Cc: <stable@vger.kernel.org>
Fixes: be0f272bfc83 ("arm64: ftrace: emit ftrace-mod.o contents through code")
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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[ Upstream commit 40ca0ce56d4bb889dc43b455c55398468115569a ]
Comparing the arm-arm's pseudocode for AArch64.PCAlignmentFault() with
AArch64.SPAlignmentFault() shows that SP faults don't copy the faulty-SP
to FAR_EL1, but this is where we read from, and the address we provide
to user-space with the BUS_ADRALN signal.
For user-space this value will be UNKNOWN due to the previous ERET to
user-space. If the last value is preserved, on systems with KASLR or KPTI
this will be the user-space link-register left in FAR_EL1 by tramp_exit().
Fix this to retrieve the original sp_el0 value, and pass this to
do_sp_pc_fault().
SP alignment faults from EL1 will cause us to take the fault again when
trying to store the pt_regs. This eventually takes us to the overflow
stack. Remove the ESR_ELx_EC_SP_ALIGN check as we will never make it
this far.
Fixes: 60ffc30d5652 ("arm64: Exception handling")
Signed-off-by: James Morse <james.morse@arm.com>
[will: change label name and fleshed out comment]
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
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[ Upstream commit cbdf8a189a66001c36007bf0f5c975d0376c5c3a ]
On a CPU that doesn't support SSBS, PSTATE[12] is RES0. In a system
where only some of the CPUs implement SSBS, we end-up losing track of
the SSBS bit across task migration.
To address this issue, let's force the SSBS bit on context switch.
Fixes: 8f04e8e6e29c ("arm64: ssbd: Add support for PSTATE.SSBS rather than trapping to EL3")
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
[will: inverted logic and added comments]
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
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commit 147b9635e6347104b91f48ca9dca61eb0fbf2a54 upstream.
If CTR_EL0.{CWG,ERG} are 0b0000 then they must be interpreted to have
their architecturally maximum values, which defeats the use of
FTR_HIGHER_SAFE when sanitising CPU ID registers on heterogeneous
machines.
Introduce FTR_HIGHER_OR_ZERO_SAFE so that these fields effectively
saturate at zero.
Fixes: 3c739b571084 ("arm64: Keep track of CPU feature registers")
Cc: <stable@vger.kernel.org> # 4.4.x-
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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commit 849adec41203ac5837c40c2d7e08490ffdef3c2c upstream.
Commit d968d2b801d8 ("ARM: 7497/1: hw_breakpoint: allow single-byte
watchpoints on all addresses") changed the validation requirements for
hardware watchpoints on arch/arm/. Update our compat layer to implement
the same relaxation.
Cc: <stable@vger.kernel.org>
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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commit bd82d4bd21880b7c4d5f5756be435095d6ae07b5 upstream.
When using IRQ priority masking to disable interrupts, in order to deal
with the PSR.I state, local_irq_save() would convert the I bit into a
PMR value (GIC_PRIO_IRQOFF). This resulted in local_irq_restore()
potentially modifying the value of PMR in undesired location due to the
state of PSR.I upon flag saving [1].
In an attempt to solve this issue in a less hackish manner, introduce
a bit (GIC_PRIO_IGNORE_PMR) for the PMR values that can represent
whether PSR.I is being used to disable interrupts, in which case it
takes precedence of the status of interrupt masking via PMR.
GIC_PRIO_PSR_I_SET is chosen such that (<pmr_value> |
GIC_PRIO_PSR_I_SET) does not mask more interrupts than <pmr_value> as
some sections (e.g. arch_cpu_idle(), interrupt acknowledge path)
requires PMR not to mask interrupts that could be signaled to the
CPU when using only PSR.I.
[1] https://www.spinics.net/lists/arm-kernel/msg716956.html
Fixes: 4a503217ce37 ("arm64: irqflags: Use ICC_PMR_EL1 for interrupt masking")
Cc: <stable@vger.kernel.org> # 5.1.x-
Reported-by: Zenghui Yu <yuzenghui@huawei.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Wei Li <liwei391@huawei.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Christoffer Dall <christoffer.dall@arm.com>
Cc: James Morse <james.morse@arm.com>
Cc: Suzuki K Pouloze <suzuki.poulose@arm.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Julien Thierry <julien.thierry@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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commit 17ce302f3117e9518395847a3120c8a108b587b8 upstream.
In the presence of any form of instrumentation, nmi_enter() should be
done before calling any traceable code and any instrumentation code.
Currently, nmi_enter() is done in handle_domain_nmi(), which is much
too late as instrumentation code might get called before. Move the
nmi_enter/exit() calls to the arch IRQ vector handler.
On arm64, it is not possible to know if the IRQ vector handler was
called because of an NMI before acknowledging the interrupt. However, It
is possible to know whether normal interrupts could be taken in the
interrupted context (i.e. if taking an NMI in that context could
introduce a potential race condition).
When interrupting a context with IRQs disabled, call nmi_enter() as soon
as possible. In contexts with IRQs enabled, defer this to the interrupt
controller, which is in a better position to know if an interrupt taken
is an NMI.
Fixes: bc3c03ccb464 ("arm64: Enable the support of pseudo-NMIs")
Cc: <stable@vger.kernel.org> # 5.1.x-
Cc: Will Deacon <will.deacon@arm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Julien Thierry <julien.thierry@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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[ Upstream commit 2af22f3ec3ca452f1e79b967f634708ff01ced8a ]
Some Qualcomm Snapdragon based laptops built to run Microsoft Windows
are clearly ACPI 5.1 based, given that that is the first ACPI revision
that supports ARM, and introduced the FADT 'arm_boot_flags' field,
which has a non-zero field on those systems.
So in these cases, infer from the ARM boot flags that the FADT must be
5.1 or later, and treat it as 5.1.
Acked-by: Sudeep Holla <sudeep.holla@arm.com>
Tested-by: Lee Jones <lee.jones@linaro.org>
Reviewed-by: Graeme Gregory <graeme.gregory@linaro.org>
Acked-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Acked-by: Hanjun Guo <guohanjun@huawei.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
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[ Upstream commit 9034f6251572a4744597c51dea5ab73a55f2b938 ]
For el0_dbg and el0_error, DAIF bits get explicitly cleared before
calling ct_user_exit.
When context tracking is disabled, DAIF gets set (almost) immediately
after. When context tracking is enabled, among the first things done
is disabling IRQs.
What is actually needed is:
- PSR.D = 0 so the system can be debugged (should be already the case)
- PSR.A = 0 so async error can be handled during context tracking
Do not clear PSR.I in those two locations.
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: James Morse <james.morse@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Julien Thierry <julien.thierry@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
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