diff options
Diffstat (limited to 'arch/powerpc/include/asm/exception-64s.h')
-rw-r--r-- | arch/powerpc/include/asm/exception-64s.h | 14 |
1 files changed, 14 insertions, 0 deletions
diff --git a/arch/powerpc/include/asm/exception-64s.h b/arch/powerpc/include/asm/exception-64s.h index 47bd4ea0837d..ebe95aa04d53 100644 --- a/arch/powerpc/include/asm/exception-64s.h +++ b/arch/powerpc/include/asm/exception-64s.h @@ -68,6 +68,14 @@ * * The nop instructions allow us to insert one or more instructions to flush the * L1-D cache when returning to userspace or a guest. + * + * powerpc relies on return from interrupt/syscall being context synchronising + * (which hrfid, rfid, and rfscv are) to support ARCH_HAS_MEMBARRIER_SYNC_CORE + * without additional synchronisation instructions. + * + * soft-masked interrupt replay does not include a context-synchronising rfid, + * but those always return to kernel, the sync is only required when returning + * to user. */ #define RFI_FLUSH_SLOT \ RFI_FLUSH_FIXUP_SECTION; \ @@ -123,6 +131,12 @@ hrfid; \ b hrfi_flush_fallback +#define RFSCV_TO_USER \ + STF_EXIT_BARRIER_SLOT; \ + RFI_FLUSH_SLOT; \ + RFSCV; \ + b rfscv_flush_fallback + #endif /* __ASSEMBLY__ */ #endif /* _ASM_POWERPC_EXCEPTION_H */ |