From 2384b36f9156c3b815a5ce5f694edc5054ab7625 Mon Sep 17 00:00:00 2001 From: Nicholas Piggin Date: Thu, 16 Jul 2020 11:35:22 +1000 Subject: powerpc: Select ARCH_HAS_MEMBARRIER_SYNC_CORE powerpc return from interrupt and return from system call sequences are context synchronising. Signed-off-by: Nicholas Piggin Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20200716013522.338318-1-npiggin@gmail.com --- arch/powerpc/include/asm/exception-64e.h | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) (limited to 'arch/powerpc/include/asm/exception-64e.h') diff --git a/arch/powerpc/include/asm/exception-64e.h b/arch/powerpc/include/asm/exception-64e.h index 54a98ef7d7fe..72b6657acd2d 100644 --- a/arch/powerpc/include/asm/exception-64e.h +++ b/arch/powerpc/include/asm/exception-64e.h @@ -204,7 +204,11 @@ exc_##label##_book3e: LOAD_REG_ADDR(r3,interrupt_base_book3e);\ ori r3,r3,vector_offset@l; \ mtspr SPRN_IVOR##vector_number,r3; - +/* + * powerpc relies on return from interrupt/syscall being context synchronising + * (which rfi is) to support ARCH_HAS_MEMBARRIER_SYNC_CORE without additional + * synchronisation instructions. + */ #define RFI_TO_KERNEL \ rfi -- cgit