[PATCH 2/5] powerpc/64s: Add new security feature flags for count cache flush
From: Michael Ellerman <mpe@ellerman.id.au>
Date: 2018-07-23 15:08:13
Subsystem:
linux for powerpc (32-bit and 64-bit), the rest · Maintainers:
Madhavan Srinivasan, Linus Torvalds
Add security feature flags to indicate the need for software to flush the count cache on context switch, and for the presence of a hardware assisted count cache flush. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> --- arch/powerpc/include/asm/security_features.h | 6 ++++++ 1 file changed, 6 insertions(+)
diff --git a/arch/powerpc/include/asm/security_features.h b/arch/powerpc/include/asm/security_features.h
index 44989b22383c..a0d47bc18a5c 100644
--- a/arch/powerpc/include/asm/security_features.h
+++ b/arch/powerpc/include/asm/security_features.h@@ -59,6 +59,9 @@ static inline bool security_ftr_enabled(unsigned long feature) // Indirect branch prediction cache disabled #define SEC_FTR_COUNT_CACHE_DISABLED 0x0000000000000020ull +// bcctr 2,0,0 triggers a hardware assisted count cache flush +#define SEC_FTR_BCCTR_FLUSH_ASSIST 0x0000000000000800ull + // Features indicating need for Spectre/Meltdown mitigations
@@ -74,6 +77,9 @@ static inline bool security_ftr_enabled(unsigned long feature) // Firmware configuration indicates user favours security over performance #define SEC_FTR_FAVOUR_SECURITY 0x0000000000000200ull +// Software required to flush count cache on context switch +#define SEC_FTR_FLUSH_COUNT_CACHE 0x0000000000000400ull + // Features enabled by default #define SEC_FTR_DEFAULT \
--
2.14.1