Will Deacon 1403a89915 arm64: sme: Use STR P to clear FFR context field in streaming SVE mode ... [ Upstream commit 893b24181b ] The FFR is a predicate register which can vary between 16 and 256 bits in size depending upon the configured vector length. When saving the SVE state in streaming SVE mode, the FFR register is inaccessible and so commit 9f58486657 ("arm64/sve: Make access to FFR optional") simply clears the FFR field of the in-memory context structure. Unfortunately, it achieves this using an unconditional 8-byte store and so if the SME vector length is anything other than 64 bytes in size we will either fail to clear the entire field or, worse, we will corrupt memory immediately following the structure. This has led to intermittent kfence splats in CI [1] and can trigger kmalloc Redzone corruption messages when running the 'fp-stress' kselftest: | ============================================================================= | BUG kmalloc-1k (Not tainted): kmalloc Redzone overwritten | ----------------------------------------------------------------------------- | | 0xffff000809bf1e22-0xffff000809bf1e27 @offset=7714. First byte 0x0 instead of 0xcc | Allocated in do_sme_acc+0x9c/0x220 age=2613 cpu=1 pid=531 | __kmalloc+0x8c/0xcc | do_sme_acc+0x9c/0x220 | ... Replace the 8-byte store with a store of a predicate register which has been zero-initialised with PFALSE, ensuring that the entire field is cleared in memory. [1] https://lore.kernel.org/r/CA+G9fYtU7HsV0R0dp4XEH5xXHSJFw8KyDf5VQrLLfMxWfxQkag@mail.gmail.com Cc: Mark Brown <broonie@kernel.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Naresh Kamboju <naresh.kamboju@linaro.org> Fixes: 9f58486657 ("arm64/sve: Make access to FFR optional") Reported-by: Linux Kernel Functional Testing <lkft@linaro.org> Signed-off-by: Will Deacon <will@kernel.org> Reviewed-by: Mark Brown <broonie@kernel.org> Tested-by: Anders Roxell <anders.roxell@linaro.org> Link: https://lore.kernel.org/r/20230628155605.22296-1-will@kernel.org Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Sasha Levin <sashal@kernel.org>		2023-07-19 16:36:25 +02:00
..
boot	arm64: dts: mt7986: increase bl2 partition on NAND of Bananapi R3	2023-07-19 16:36:04 +02:00
configs	arm64: defconfig: enable building the nvmem-reboot-mode module	2023-04-17 16:38:41 +02:00
crypto
hyperv	arm64/hyperv: Use CPUHP_AP_HYPERV_ONLINE state to fix CPU online sequencing	2023-06-17 23:09:47 +00:00
include	arm64: sme: Use STR P to clear FFR context field in streaming SVE mode	2023-07-19 16:36:25 +02:00
kernel	arm64: mte: Do not set PG_mte_tagged if tags were not initialized	2023-05-16 14:59:16 +01:00
kvm	KVM: arm64: Use raw_smp_processor_id() in kvm_pmu_probe_armpmu()	2023-06-07 16:48:34 +01:00
lib	arm: uaccess: Remove memcpy_page_flushcache()	2023-03-27 16:26:19 +01:00
mm	arch/arm64/mm/fault: Fix undeclared variable error in do_page_fault()	2023-07-05 18:30:30 +01:00
net	bpf, arm64: Fixed a BTI error on returning to patched function	2023-04-03 17:44:03 +02:00
tools	s390:	2023-05-01 12:06:20 -07:00
xen
Kbuild
Kconfig	arm64/mm: Convert to using lock_mm_and_find_vma()	2023-07-01 13:12:39 +02:00
Kconfig.debug
Kconfig.platforms
Makefile