From 74726fda9fe306f848088ef73ec266cae0470d5b Mon Sep 17 00:00:00 2001 From: Christophe Leroy Date: Sat, 7 Oct 2023 12:46:19 +0200 Subject: [PATCH] powerpc/code-patching: Perform hwsync in __patch_instruction() in case of failure Commit c28c15b6d28a ("powerpc/code-patching: Use temporary mm for Radix MMU") added a hwsync for when __patch_instruction() fails, we results in a quite odd unbalanced logic. Instead of calling mb() when __patch_instruction() returns an error, call mb() in the __patch_instruction()'s error path directly. Signed-off-by: Christophe Leroy Signed-off-by: Michael Ellerman Link: https://msgid.link/e88b154eaf2efd9ff177d472d3411dcdec8ff4f5.1696675567.git.christophe.leroy@csgroup.eu --- arch/powerpc/lib/code-patching.c | 5 +---- 1 file changed, 1 insertion(+), 4 deletions(-) diff --git a/arch/powerpc/lib/code-patching.c b/arch/powerpc/lib/code-patching.c index b00112d7ad467..7a47a871e6b8e 100644 --- a/arch/powerpc/lib/code-patching.c +++ b/arch/powerpc/lib/code-patching.c @@ -38,6 +38,7 @@ static int __patch_instruction(u32 *exec_addr, ppc_inst_t instr, u32 *patch_addr return 0; failed: + mb(); /* sync */ return -EPERM; } @@ -309,10 +310,6 @@ static int __do_patch_instruction_mm(u32 *addr, ppc_inst_t instr) err = __patch_instruction(addr, instr, patch_addr); - /* hwsync performed by __patch_instruction (sync) if successful */ - if (err) - mb(); /* sync */ - /* context synchronisation performed by __patch_instruction (isync or exception) */ stop_using_temp_mm(patching_mm, orig_mm); -- 2.30.2