From: Michael Ellerman <mpe@xxxxxxxxxxxxxx> commit dc8c6cce9a26a51fc19961accb978217a3ba8c75 upstream. 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@xxxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- arch/powerpc/include/asm/security_features.h | 6 ++++++ 1 file changed, 6 insertions(+) --- 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( // 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( // 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 \