linux/arch/arm64/kernel
Will Deacon ab3584014c arm64: ssbs: Fix context-switch when SSBS is present on all CPUs
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>
History 2020-02-19 19:54:04 +01:00
..
probes arm64: remove __exception annotations 2019-10-28 11:22:38 +00:00
vdso arm64: vdso: Remove stale files from old assembly implementation 2019-10-07 11:07:16 +01:00
vdso32 arm64: vdso32: Rename COMPATCC to CC_COMPAT 2019-10-07 13:32:13 +01:00
.gitignore arm64: Build infrastructure 2012-09-17 13:42:21 +01:00
acpi.c arm64: acpi: fix DAIF manipulation with pNMI 2020-02-11 04:36:46 -08:00
acpi_numa.c acpi: Create subtable parsing infrastructure 2019-04-04 18:41:12 +02:00
acpi_parking_protocol.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 234 2019-06-19 17:09:07 +02:00
alternative.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 234 2019-06-19 17:09:07 +02:00
armv8_deprecated.c arm64: armv8_deprecated: Checking return value for memory allocation 2019-10-08 13:34:04 +01:00
asm-offsets.c arm64: asm-offsets: add S_FP 2019-11-06 14:17:34 +00:00
cacheinfo.c arm64 updates for 5.3: 2019-07-08 09:54:55 -07:00
cpu-reset.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
cpu-reset.S treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
cpu_errata.c arm64: cpu_errata: Add Hisilicon TSV110 to spectre-v2 safe list 2019-12-20 17:57:22 +00:00
cpu_ops.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 234 2019-06-19 17:09:07 +02:00
cpufeature.c arm64: cpufeature: Set the FP/SIMD compat HWCAP bits properly 2020-02-14 16:53:03 -05:00
cpuidle.c PSCI: cpuidle: Refactor CPU suspend power_state parameter handling 2019-08-09 17:51:39 +01:00
cpuinfo.c arm64: cpufeature: Fix typos in comment 2019-10-25 16:19:44 +01:00
crash_core.c arm64: kernel: arch_crash_save_vmcoreinfo() should depend on CONFIG_CRASH_CORE 2018-09-11 11:08:49 +01:00
crash_dump.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
debug-monitors.c arm64: Remove unneeded rcu_read_lock from debug handlers 2019-08-01 15:00:27 +01:00
efi-entry.S treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
efi-header.S treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
efi-rt-wrapper.S treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
efi.c mm/pgtable: drop pgtable_t variable from pte_fn_t functions 2019-07-12 11:05:46 -07:00
entry-common.c arm64: entry-common: don't touch daif before bp-hardening 2019-10-28 11:22:54 +00:00
entry-fpsimd.S treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 234 2019-06-19 17:09:07 +02:00
entry-ftrace.S arm64: ftrace: fix ifdeffery 2019-12-06 13:25:14 +00:00
entry.S arm64: kernel: Correct annotation of end of el0_sync 2020-02-14 16:53:03 -05:00
fpsimd.c arm64: nofpsmid: Handle TIF_FOREIGN_FPSTATE flag cleanly 2020-02-14 16:53:04 -05:00
ftrace.c arm64: ftrace: minimize ifdeffery 2019-11-06 14:17:36 +00:00
head.S Merge branches 'for-next/52-bit-kva', 'for-next/cpu-topology', 'for-next/error-injection', 'for-next/perf', 'for-next/psci-cpuidle', 'for-next/rng', 'for-next/smpboot', 'for-next/tbi' and 'for-next/tlbi' into for-next/core 2019-08-30 12:46:12 +01:00
hibernate-asm.S arm64: mm: Logic to make offset_ttbr1 conditional 2019-08-09 11:17:24 +01:00
hibernate.c arm64: hibernate: check pgd table allocation 2019-10-14 17:57:29 -07:00
hw_breakpoint.c Printk changes for 5.5 2019-11-25 19:40:40 -08:00
hyp-stub.S treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 234 2019-06-19 17:09:07 +02:00
image-vars.h arm64/efi: Move variable assignments after SECTIONS 2019-08-14 17:18:15 +01:00
image.h arm64/efi: Move variable assignments after SECTIONS 2019-08-14 17:18:15 +01:00
insn.c arm64: insn: consistently handle exit text 2019-12-04 11:32:20 +00:00
io.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 234 2019-06-19 17:09:07 +02:00
irq.c arm64 updates for 5.3: 2019-07-08 09:54:55 -07:00
jump_label.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 234 2019-06-19 17:09:07 +02:00
kaslr.c arm64: kaslr: Check command line before looking for a seed 2019-11-08 17:36:51 +00:00
kexec_image.c arm64/kexec: Use consistent convention of initializing 'kxec_buf.mem' with KEXEC_BUF_MEM_UNKNOWN 2019-08-05 11:06:33 +01:00
kgdb.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 234 2019-06-19 17:09:07 +02:00
kuser32.S docs: arm: convert docs to ReST and rename to *.rst 2019-07-15 09:20:24 -03:00
machine_kexec.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
machine_kexec_file.c Merge branches 'for-next/52-bit-kva', 'for-next/cpu-topology', 'for-next/error-injection', 'for-next/perf', 'for-next/psci-cpuidle', 'for-next/rng', 'for-next/smpboot', 'for-next/tbi' and 'for-next/tlbi' into for-next/core 2019-08-30 12:46:12 +01:00
Makefile arm64: entry: convert el1_sync to C 2019-10-28 11:22:47 +00:00
module-plts.c arm64: implement ftrace with regs 2019-11-06 14:17:35 +00:00
module.c arm64: implement ftrace with regs 2019-11-06 14:17:35 +00:00
module.lds arm64: ftrace: emit ftrace-mod.o contents through code 2017-12-01 13:04:59 +00:00
paravirt.c arm64: Retrieve stolen time as paravirtualized guest 2019-10-21 19:20:31 +01:00
pci.c pci-v5.3-changes 2019-07-15 20:44:49 -07:00
perf_callchain.c arm64: stacktrace: Factor out backtrace initialisation 2019-07-22 11:44:08 +01:00
perf_event.c arm64: perf: Simplify the ARMv8 PMUv3 event attributes 2019-11-01 14:51:19 +00:00
perf_regs.c compat: Move compat_timespec/ timeval to compat_time.h 2018-04-19 13:29:54 +02:00
pointer_auth.c arm64: ptr auth: Move per-thread keys from thread_info to thread_struct 2018-12-13 16:42:47 +00:00
process.c arm64: ssbs: Fix context-switch when SSBS is present on all CPUs 2020-02-19 19:54:04 +01:00
psci.c arm64: psci: Reduce the waiting time for cpu_psci_cpu_kill() 2019-10-25 16:29:11 +01:00
ptrace.c arm64: ptrace: nofpsimd: Fail FP/SIMD regset operations 2020-02-14 16:53:03 -05:00
reloc_test_core.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
reloc_test_syms.S treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
relocate_kernel.S treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
return_address.c arm64: unwind: Prohibit probing on return_address() 2019-08-01 15:00:26 +01:00
sdei.c firmware: arm_sdei: use common SMCCC_CONDUIT_* 2019-10-14 10:55:14 +01:00
setup.c Merge branches 'for-next/52-bit-kva', 'for-next/cpu-topology', 'for-next/error-injection', 'for-next/perf', 'for-next/psci-cpuidle', 'for-next/rng', 'for-next/smpboot', 'for-next/tbi' and 'for-next/tlbi' into for-next/core 2019-08-30 12:46:12 +01:00
signal.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 234 2019-06-19 17:09:07 +02:00
signal32.c arm64: compat: Get sigreturn trampolines from vDSO 2019-06-22 21:21:09 +02:00
sigreturn32.S arm64: compat: Split kuser32 2019-04-23 18:01:57 +01:00
sleep.S arm64: kernel: use aff3 instead of aff2 in comment 2019-06-04 14:51:01 +01:00
smccc-call.S treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 174 2019-05-30 11:26:41 -07:00
smp.c arm64 updates for 5.5: 2019-12-06 14:18:01 -08:00
smp_spin_table.c arm64: prefer __section from compiler_attributes.h 2019-08-13 18:32:15 +01:00
ssbd.c arm64: ssbd: explicitly depend on <linux/prctl.h> 2019-06-17 18:38:10 +01:00
stacktrace.c arm64: unwind: Prohibit probing on return_address() 2019-08-01 15:00:26 +01:00
suspend.c arm64: mm: Support Common Not Private translations 2018-09-18 12:02:27 +01:00
sys.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 234 2019-06-19 17:09:07 +02:00
sys32.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 452 2019-06-19 17:09:08 +02:00
sys_compat.c arm64: Silence clang warning on mismatched value/register sizes 2019-10-28 09:13:21 +00:00
syscall.c arm64: Remove asmlinkage from updated functions 2019-10-28 11:22:51 +00:00
time.c arm64: Retrieve stolen time as paravirtualized guest 2019-10-21 19:20:31 +01:00
topology.c Merge tag 'common/for-v5.4-rc1/cpu-topology' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux into for-next/cpu-topology 2019-08-14 10:07:00 +01:00
trace-events-emulation.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
traps.c Merge branch 'for-next/entry-s-to-c' into for-next/core 2019-10-28 17:02:56 +00:00
vdso.c arm64: compat: VDSO setup for compat layer 2019-06-22 21:21:08 +02:00
vmlinux.lds.S arm64 updates for 5.5: 2019-12-06 14:18:01 -08:00