From: Josh Poimboeuf <[email protected]> [ Upstream commit a7e47f26039c26312a4144c3001b4e9fa886bd45 ]
After an objtool improvement, it's reporting that __memcpy_mcsafe() is calling mcsafe_handle_tail() with AC=1: arch/x86/lib/memcpy_64.o: warning: objtool: .fixup+0x13: call to mcsafe_handle_tail() with UACCESS enabled arch/x86/lib/memcpy_64.o: warning: objtool: __memcpy_mcsafe()+0x34: (alt) arch/x86/lib/memcpy_64.o: warning: objtool: __memcpy_mcsafe()+0xb: (branch) arch/x86/lib/memcpy_64.o: warning: objtool: __memcpy_mcsafe()+0x0: <=== (func) mcsafe_handle_tail() is basically an extension of __memcpy_mcsafe(), so AC=1 is supposed to be set. Add mcsafe_handle_tail() to the uaccess safe list. Signed-off-by: Josh Poimboeuf <[email protected]> Signed-off-by: Thomas Gleixner <[email protected]> Tested-by: Nick Desaulniers <[email protected]> Acked-by: Peter Zijlstra (Intel) <[email protected]> Link: https://lkml.kernel.org/r/035c38f7eac845281d3c3d36749144982e06e58c.1563413318.git.jpoim...@redhat.com Signed-off-by: Sasha Levin <[email protected]> --- tools/objtool/check.c | 1 + 1 file changed, 1 insertion(+) diff --git a/tools/objtool/check.c b/tools/objtool/check.c index 172f99195726..f5c3b97051a7 100644 --- a/tools/objtool/check.c +++ b/tools/objtool/check.c @@ -488,6 +488,7 @@ static const char *uaccess_safe_builtin[] = { /* misc */ "csum_partial_copy_generic", "__memcpy_mcsafe", + "mcsafe_handle_tail", "ftrace_likely_update", /* CONFIG_TRACE_BRANCH_PROFILING */ NULL }; -- 2.20.1
