D Scott Phillips 38e0257e0e arm64: errata: Fix exec handling in erratum 1418040 workaround ... The erratum 1418040 workaround enables CNTVCT_EL1 access trapping in EL0 when executing compat threads. The workaround is applied when switching between tasks, but the need for the workaround could also change at an exec(), when a non-compat task execs a compat binary or vice versa. Apply the workaround in arch_setup_new_exec(). This leaves a small window of time between SET_PERSONALITY and arch_setup_new_exec where preemption could occur and confuse the old workaround logic that compares TIF_32BIT between prev and next. Instead, we can just read cntkctl to make sure it's in the state that the next task needs. I measured cntkctl read time to be about the same as a mov from a general-purpose register on N1. Update the workaround logic to examine the current value of cntkctl instead of the previous task's compat state. Fixes: d49f7d7376 ("arm64: Move handling of erratum 1418040 into C code") Cc: <stable@vger.kernel.org> # 5.9.x Signed-off-by: D Scott Phillips <scott@os.amperecomputing.com> Reviewed-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20211220234114.3926-1-scott@os.amperecomputing.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>		2021-12-22 15:18:19 +00:00
..
boot	arm64: dts: exynos: drop samsung,ufs-shareability-reg-offset in ExynosAutov9	2021-11-25 14:46:00 +01:00
configs	ARM: defconfig updates for 5.16	2021-11-03 17:07:02 -07:00
crypto	crypto: arm64/aes-ccm - avoid by-ref argument for ce_aes_ccm_auth_data	2021-09-17 11:05:11 +08:00
hyperv
include	asm-generic: introduce io_stop_wc() and add implementation for ARM64	2021-12-22 10:44:53 +00:00
kernel	arm64: errata: Fix exec handling in erratum 1418040 workaround	2021-12-22 15:18:19 +00:00
kvm	arm64/kvm: Fix bitrotted comment for SVE handling in handle_exit.c	2021-12-06 16:09:34 +00:00
lib	Kbuild updates for v5.16	2021-11-08 09:15:45 -08:00
mm	arm64: remove __dma_*_area() aliases	2021-12-15 11:19:41 +00:00
net	arm64 updates for 5.16	2021-11-01 16:33:53 -07:00
tools	Merge branch 'for-next/trbe-errata' into for-next/core	2021-10-29 12:25:33 +01:00
xen	xen: allow pv-only hypercalls only with CONFIG_XEN_PV	2021-11-02 08:11:01 -05:00
Kbuild	kbuild: use more subdir- for visiting subdirectories while cleaning	2021-10-24 13:49:46 +09:00
Kconfig	Merge branch 'akpm' (patches from Andrew)	2021-11-06 14:08:17 -07:00
Kconfig.debug
Kconfig.platforms	ARM: SoC drivers for 5.16	2021-11-03 17:00:52 -07:00
Makefile	kbuild: use more subdir- for visiting subdirectories while cleaning	2021-10-24 13:49:46 +09:00