From: Marc Zyngier <maz@kernel.org> mainline inclusion from mainline-v6.9-rc1 commit 87b8cf2387c5ee79576988b2e72b84eeb92c57ec category: feature bugzilla: https://gitcode.com/openeuler/kernel/issues/10066 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i... ---------------------------------------- When triggering a CPU hotplug scenario, we reparse the CPU feature with SCOPE_LOCAL_CPU, for which we use __read_sysreg_by_encoding() to get the HW value for this CPU. As it turns out, we're missing the handling for ID_AA64MMFR4_EL1, and trigger a BUG(). Funnily enough, Marek isn't completely happy about that. Add the damn register to the list. Fixes: 805bb61f8279 ("arm64: cpufeature: Add ID_AA64MMFR4_EL1 handling") Reported-by: Marek Szyprowski <m.szyprowski@samsung.com> Tested-by: Marek Szyprowski <m.szyprowski@samsung.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20240212144736.1933112-2-maz@kernel.org Signed-off-by: Oliver Upton <oliver.upton@linux.dev> Conflicts: arch/arm64/kernel/cpufeature.c [Fix context conflicts.] Signed-off-by: Zeng Heng <zengheng4@huawei.com> --- arch/arm64/kernel/cpufeature.c | 1 + 1 file changed, 1 insertion(+) diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c index 547d0ef61035..ca1c45d50f8b 100644 --- a/arch/arm64/kernel/cpufeature.c +++ b/arch/arm64/kernel/cpufeature.c @@ -1523,6 +1523,7 @@ u64 __read_sysreg_by_encoding(u32 sys_id) read_sysreg_case(SYS_ID_AA64MMFR1_EL1); read_sysreg_case(SYS_ID_AA64MMFR2_EL1); read_sysreg_case(SYS_ID_AA64MMFR3_EL1); + read_sysreg_case(SYS_ID_AA64MMFR4_EL1); read_sysreg_case(SYS_ID_AA64ISAR0_EL1); read_sysreg_case(SYS_ID_AA64ISAR1_EL1); read_sysreg_case(SYS_ID_AA64ISAR2_EL1); -- 2.33.0