4.17-stable review patch. If anyone has any objections, please let me know.
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From: Marc Zyngier marc.zyngier@arm.com
commit c32e1736ca03904c03de0e4459a673be194f56fd upstream.
We're about to need the mitigation state in various parts of the kernel in order to do the right thing for userspace and guests.
Let's expose an accessor that will let other subsystems know about the state.
Reviewed-by: Julien Grall julien.grall@arm.com Reviewed-by: Mark Rutland mark.rutland@arm.com Acked-by: Will Deacon will.deacon@arm.com Signed-off-by: Marc Zyngier marc.zyngier@arm.com Signed-off-by: Catalin Marinas catalin.marinas@arm.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- arch/arm64/include/asm/cpufeature.h | 10 ++++++++++ 1 file changed, 10 insertions(+)
--- a/arch/arm64/include/asm/cpufeature.h +++ b/arch/arm64/include/asm/cpufeature.h @@ -543,6 +543,16 @@ static inline u64 read_zcr_features(void #define ARM64_SSBD_FORCE_ENABLE 2 #define ARM64_SSBD_MITIGATED 3
+static inline int arm64_get_ssbd_state(void) +{ +#ifdef CONFIG_ARM64_SSBD + extern int ssbd_state; + return ssbd_state; +#else + return ARM64_SSBD_UNKNOWN; +#endif +} + #endif /* __ASSEMBLY__ */
#endif