From: Julien Grall julien.grall@arm.com
mainline inclusion from mainline-v5.9-rc1 commit 7230f7e99fec category: bugfix bugzilla: NA CVE: NA
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The HWCAP framework will detect a new capability based on the sanitized version of the ID registers.
Sanitization is based on a whitelist, so any field not described will end up to be zeroed.
At the moment, ID_AA64ISAR1_EL1.FRINTTS is not described in ftr_id_aa64isar1. This means the field will be zeroed and therefore the userspace will not be able to see the HWCAP even if the hardware supports the feature.
This can be fixed by describing the field in ftr_id_aa64isar1.
Fixes: ca9503fc9e98 ("arm64: Expose FRINT capabilities to userspace") Signed-off-by: Julien Grall julien.grall@arm.com Cc: mark.brown@arm.com Signed-off-by: Will Deacon will@kernel.org Signed-off-by: Wang Faren wangfaren@huawei.com Reviewed-by: Xie XiuQi xiexiuqi@huawei.com Signed-off-by: Yang Yingliang yangyingliang@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 b986dd94206a..4e30ecaaa0b9 100644 --- a/arch/arm64/kernel/cpufeature.c +++ b/arch/arm64/kernel/cpufeature.c @@ -148,6 +148,7 @@ static const struct arm64_ftr_bits ftr_id_aa64isar0[] = {
static const struct arm64_ftr_bits ftr_id_aa64isar1[] = { ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_SB_SHIFT, 4, 0), + ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_FRINTTS_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_PTR_AUTH), FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR1_GPI_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_PTR_AUTH),