commit 3cce50dfec upstream.
The arm64 PMU updates the event counters and reprograms the
counters in the overflow IRQ handler without disabling the
PMU. This could potentially cause skews in for group counters,
where the overflowed counters may potentially loose some event
counts, while they are reprogrammed. To prevent this, disable
the PMU while we process the counter overflows and enable it
right back when we are done.
This patch also moves the PMU stop/start routines to avoid a
forward declaration.
Suggested-by: Mark Rutland <mark.rutland@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Aman Priyadarshi <apeureka@amazon.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 388708028e ]
The arm64 assembler in binutils 2.32 and above generates a program
property note in a note section, .note.gnu.property, to encode used x86
ISAs and features. But the kernel linker script only contains a single
NOTE segment:
PHDRS
{
text PT_LOAD FLAGS(5) FILEHDR PHDRS; /* PF_R|PF_X */
dynamic PT_DYNAMIC FLAGS(4); /* PF_R */
note PT_NOTE FLAGS(4); /* PF_R */
}
The NOTE segment generated by the vDSO linker script is aligned to 4 bytes.
But the .note.gnu.property section must be aligned to 8 bytes on arm64.
$ readelf -n vdso64.so
Displaying notes found in: .note
Owner Data size Description
Linux 0x00000004 Unknown note type: (0x00000000)
description data: 06 00 00 00
readelf: Warning: note with invalid namesz and/or descsz found at offset 0x20
readelf: Warning: type: 0x78, namesize: 0x00000100, descsize: 0x756e694c, alignment: 8
Since the note.gnu.property section in the vDSO is not checked by the
dynamic linker, discard the .note.gnu.property sections in the vDSO.
Similar to commit 4caffe6a28 ("x86/vdso: Discard .note.gnu.property
sections in vDSO"), but for arm64.
Signed-off-by: Bill Wendling <morbo@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Link: https://lore.kernel.org/r/20210423205159.830854-1-morbo@google.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 1d676673d6 ]
Currently we advertise the ID_AA6DFR0_EL1.TRACEVER for the guest,
when the trace register accesses are trapped (CPTR_EL2.TTA == 1).
So, the guest will get an undefined instruction, if trusts the
ID registers and access one of the trace registers.
Lets be nice to the guest and hide the feature to avoid
unexpected behavior.
Even though this can be done at KVM sysreg emulation layer,
we do this by removing the TRACEVER from the sanitised feature
register field. This is fine as long as the ETM drivers
can handle the individual trace units separately, even
when there are differences among the CPUs.
Cc: Will Deacon <will@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20210323120647.454211-2-suzuki.poulose@arm.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 141f8202cf ]
The ppos points to a position in the old kernel memory (and in case of
arm64 in the crash kernel since elfcorehdr is passed as a segment). The
function should update the ppos by the amount that was read. This bug is
not exposed by accident, but other platforms update this value properly.
So, fix it in ARM64 version of elfcorehdr_read() as well.
Signed-off-by: Pavel Tatashin <pasha.tatashin@soleen.com>
Fixes: e62aaeac42 ("arm64: kdump: provide /proc/vmcore file")
Reviewed-by: Tyler Hicks <tyhicks@linux.microsoft.com>
Link: https://lore.kernel.org/r/20210319205054.743368-1-pasha.tatashin@soleen.com
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit f5c6d0fcf9 upstream.
These plt* and .text.ftrace_trampoline sections specified for arm64 have
non-zero addressses. Non-zero section addresses in a relocatable ELF would
confuse GDB when it tries to compute the section offsets and it ends up
printing wrong symbol addresses. Therefore, set them to zero, which mirrors
the change in commit 5d8591bc0f ("module: set ksymtab/kcrctab* section
addresses to 0x0").
Reported-by: Frank van der Linden <fllinden@amazon.com>
Signed-off-by: Shaoying Xu <shaoyi@amazon.com>
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20210216183234.GA23876@amazon.com
Signed-off-by: Will Deacon <will@kernel.org>
[shaoyi@amazon.com: made same changes in arch/arm64/kernel/module.lds for 5.4]
Signed-off-by: Shaoying Xu <shaoyi@amazon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 9d41053e8d ]
Although there has been a bit of back and forth on the subject, it
appears that invalidating TLBs requires an ISB instruction when FEAT_ETS
is not implemented by the CPU.
From the bible:
| In an implementation that does not implement FEAT_ETS, a TLB
| maintenance instruction executed by a PE, PEx, can complete at any
| time after it is issued, but is only guaranteed to be finished for a
| PE, PEx, after the execution of DSB by the PEx followed by a Context
| synchronization event
Add the missing ISB in __primary_switch, just in case.
Fixes: 3c5e9f238b ("arm64: head.S: move KASLR processing out of __enable_mmu()")
Suggested-by: Will Deacon <will@kernel.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20210224093738.3629662-3-maz@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 98448cdfe7 ]
We don't need to be quite as strict about mismatched AArch32 support,
which is good because the friendly hardware folks have been busy
mismatching this to their hearts' content.
* We don't care about EL2 or EL3 (there are silly comments concerning
the latter, so remove those)
* EL1 support is gated by the ARM64_HAS_32BIT_EL1 capability and handled
gracefully when a mismatch occurs
* EL0 support is gated by the ARM64_HAS_32BIT_EL0 capability and handled
gracefully when a mismatch occurs
Relax the AArch32 checks to FTR_NONSTRICT.
Tested-by: Sai Prakash Ranjan <saiprakash.ranjan@codeaurora.org>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20200421142922.18950-8-will@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit e9ee186bb7 upstream.
KVM has a one instruction window where it will allow an SError exception
to be consumed by the hypervisor without treating it as a hypervisor bug.
This is used to consume asynchronous external abort that were caused by
the guest.
As we are about to add another location that survives unexpected exceptions,
generalise this code to make it behave like the host's extable.
KVM's version has to be mapped to EL2 to be accessible on nVHE systems.
The SError vaxorcism code is a one instruction window, so has two entries
in the extable. Because the KVM code is copied for VHE and nVHE, we end up
with four entries, half of which correspond with code that isn't mapped.
Cc: stable@vger.kernel.org # v4.14
Signed-off-by: James Morse <james.morse@arm.com>
Reviewed-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 5afc78551b ]
Rather than open-code test_tsk_thread_flag() at each callsite, simply
replace the couple of offenders with calls to test_tsk_thread_flag()
directly.
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 3a5a4366ce upstream.
Luis reports that, when reverse debugging with GDB, single-step does not
function as expected on arm64:
| I've noticed, under very specific conditions, that a PTRACE_SINGLESTEP
| request by GDB won't execute the underlying instruction. As a consequence,
| the PC doesn't move, but we return a SIGTRAP just like we would for a
| regular successful PTRACE_SINGLESTEP request.
The underlying problem is that when the CPU register state is restored
as part of a reverse step, the SPSR.SS bit is cleared and so the hardware
single-step state can transition to the "active-pending" state, causing
an unexpected step exception to be taken immediately if a step operation
is attempted.
In hindsight, we probably shouldn't have exposed SPSR.SS in the pstate
accessible by the GPR regset, but it's a bit late for that now. Instead,
simply prevent userspace from configuring the bit to a value which is
inconsistent with the TIF_SINGLESTEP state for the task being traced.
Cc: <stable@vger.kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Keno Fischer <keno@juliacomputing.com>
Link: https://lore.kernel.org/r/1eed6d69-d53d-9657-1fc9-c089be07f98c@linaro.org
Reported-by: Luis Machado <luis.machado@linaro.org>
Tested-by: Luis Machado <luis.machado@linaro.org>
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 5679b28142 ]
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>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 3c4d9137ee ]
Return statements in functions returning bool should use true or false
instead of an integer value. This code was detected with the help of
Coccinelle.
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit f7b93d4294 ]
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>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 8523c00626 ]
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>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 24ebec25fb ]
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>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit a25ffd3a63 ]
Printing raw pointer values in backtraces has potential security
implications and are of questionable value anyway.
This patch follows x86's lead and removes the "Exception stack:" dump
from kernel backtraces, as well as converting PC/LR values to symbols
such as "sysrq_handle_crash+0x20/0x30".
Tested-by: Laura Abbott <labbott@redhat.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit fc2266011a 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: 2d888f48e0 ("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: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit f50b7daccc 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: 78fd584cde ("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: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit fca3d33d8a 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: cbdf8a189a ("arm64: Force SSBS on context switch")
Reviewed-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 52f73c383b 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).
Cc: stable@vger.kernel.org # v4.14
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: Sasha Levin <sashal@kernel.org>
commit 7559950aef 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.
Cc: stable@vger.kernel.org # v4.14
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: Sasha Levin <sashal@kernel.org>
commit 449443c03d 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: 82e0191a1a ("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: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit dc0e36581e upstream.
Since commit d3aec8a28b ("arm64: capabilities: Restrict KPTI
detection to boot-time CPUs") we rely on errata flags being already
populated during feature enumeration. The order of errata and
features was flipped as part of commit ed478b3f9e ("arm64:
capabilities: Group handling of features and errata workarounds").
Return to the orginal order of errata and feature evaluation to
ensure errata flags are present during feature evaluation.
Fixes: ed478b3f9e ("arm64: capabilities: Group handling of
features and errata workarounds")
CC: Suzuki K Poulose <suzuki.poulose@arm.com>
CC: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Dirk Mueller <dmueller@suse.com>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Juerg Haefliger <juergh@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 193383043f upstream.
Instead of open coding the generation of page table entries, use the
macros/functions that exist for this - pfn_p*d and p*d_populate. Most
code in the kernel already uses these macros, this patch tries to fix
up the few places that don't. This is useful for the next patch in this
series, which needs to change the page table entry logic, and it's
better to have that logic in one place.
The KVM extended ID map is special, since we're creating a level above
CONFIG_PGTABLE_LEVELS and the required function isn't available. Leave
it as is and add a comment to explain it. (The normal kernel ID map code
doesn't need this change because its page tables are created in assembly
(__create_page_tables)).
Tested-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Tested-by: Bob Picco <bob.picco@oracle.com>
Reviewed-by: Bob Picco <bob.picco@oracle.com>
Signed-off-by: Kristina Martsenko <kristina.martsenko@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 12eb369125 upstream.
An allnoconfig build complains about unused symbols due to functions
that are called via conditional cpufeature and cpu_errata table entries.
Annotate these as __maybe_unused if they are likely to be generic, or
predicate their compilation on the same option as the table entry if
they are specific to a given alternative.
Signed-off-by: Will Deacon <will.deacon@arm.com>
[Just a portion of the original patch]
Signed-off-by: Jisheng Zhang <Jisheng.Zhang@synaptics.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit bfcef4ab1d ]
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: Sasha Levin <sashal@kernel.org>
[ Upstream commit f357b3a7e1 ]
The __cpu_up() routine ignores the errors reported by the firmware
for a CPU bringup operation and looks for the error status set by the
booting CPU. If the CPU never entered the kernel, we could end up
in assuming stale error status, which otherwise would have been
set/cleared appropriately by the booting CPU.
Reported-by: Steve Capper <steve.capper@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit a96a33b1ca ]
For cases where there is a mismatch in ARMv8.2-LVA support between CPUs
we have to be careful in allowing secondary CPUs to boot if 52-bit
virtual addresses have already been enabled on the boot CPU.
This patch adds code to the secondary startup path. If the boot CPU has
enabled 52-bit VAs then ID_AA64MMFR2_EL1 is checked to see if the
secondary can also enable 52-bit support. If not, the secondary is
prevented from booting and an error message is displayed indicating why.
Technically this patch could be implemented using the cpufeature code
when considering 52-bit userspace support. However, we employ low level
checks here as the cpufeature code won't be able to run if we have
mismatched 52-bit kernel va support.
Signed-off-by: Steve Capper <steve.capper@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit e4ba15debc upstream.
The bad_mode() handler is called if we encounter an uunknown exception,
with the expectation that the subsequent call to panic() will halt the
system. Unfortunately, if the exception calling bad_mode() is taken from
EL0, then the call to die() can end up killing the current user task and
calling schedule() instead of falling through to panic().
Remove the die() call altogether, since we really want to bring down the
machine in this "impossible" case.
Signed-off-by: Hari Vyas <hari.vyas@broadcom.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit dd8a1f1348 ]
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: Sasha Levin <sashal@kernel.org>
[ Upstream commit a111b7c0f2 ]
Configure arm64 runtime CPU speculation bug mitigations in accordance
with the 'mitigations=' cmdline option. This affects Meltdown, Spectre
v2, and Speculative Store Bypass.
The default behavior is unchanged.
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
[will: reorder checks so KASLR implies KPTI and SSBS is affected by cmdline]
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit cbdf8a189a ]
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: 8f04e8e6e2 ("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: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit eb337cdfcd ]
SSBS provides a relatively cheap mitigation for SSB, but it is still a
mitigation and its presence does not indicate that the CPU is unaffected
by the vulnerability.
Tweak the mitigation logic so that we report the correct string in sysfs.
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 526e065dbc ]
Return status based on ssbd_state and __ssb_safe. If the
mitigation is disabled, or the firmware isn't responding then
return the expected machine state based on a whitelist of known
good cores.
Given a heterogeneous machine, the overall machine vulnerability
defaults to safe but is reset to unsafe when we miss the whitelist
and the firmware doesn't explicitly tell us the core is safe.
In order to make that work we delay transitioning to vulnerable
until we know the firmware isn't responding to avoid a case
where we miss the whitelist, but the firmware goes ahead and
reports the core is not vulnerable. If all the cores in the
machine have SSBS, then __ssb_safe will remain true.
Tested-by: Stefan Wahren <stefan.wahren@i2se.com>
Signed-off-by: Jeremy Linton <jeremy.linton@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Suzuki K Poulose