D Scott Phillips bf0d4ae5c6 arm64: errata: Fix exec handling in erratum 1418040 workaround ... commit 38e0257e0e6f4fef2aa2966b089b56a8b1cfb75c upstream. 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> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		2022-02-01 17:25:40 +01:00
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boot	arm64: dts: qcom: msm8996: drop not documented adreno properties	2022-01-27 10:54:34 +01:00
configs
crypto
include	KVM: arm64: Avoid setting the upper 32 bits of TCR_EL2 and CPTR_EL2 to 1	2021-12-08 09:03:22 +01:00
kernel	arm64: errata: Fix exec handling in erratum 1418040 workaround	2022-02-01 17:25:40 +01:00
kvm	KVM: arm64: Save PSTATE early on exit	2021-12-17 10:14:39 +01:00
lib	arm64: clear_page() shouldn't use DC ZVA when DCZID_EL0.DZP == 1	2022-01-27 10:53:54 +01:00
mm
net
xen
Kbuild
Kconfig	arm64: vdso32: require CROSS_COMPILE_COMPAT for gcc+bfd	2021-12-29 12:25:53 +01:00
Kconfig.debug
Kconfig.platforms
Makefile