From: Josh Poimboeuf Date: Thu, 18 Jul 2019 01:36:46 +0000 (-0500) Subject: objtool: Add mcsafe_handle_tail() to the uaccess safe list X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=a7e47f26039c26312a4144c3001b4e9fa886bd45;p=linux.git objtool: Add mcsafe_handle_tail() to the uaccess safe list 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 Signed-off-by: Thomas Gleixner Tested-by: Nick Desaulniers Acked-by: Peter Zijlstra (Intel) Link: https://lkml.kernel.org/r/035c38f7eac845281d3c3d36749144982e06e58c.1563413318.git.jpoimboe@redhat.com --- diff --git a/tools/objtool/check.c b/tools/objtool/check.c index 2f8ba03682310..f9494ff8c286f 100644 --- a/tools/objtool/check.c +++ b/tools/objtool/check.c @@ -490,6 +490,7 @@ static const char *uaccess_safe_builtin[] = { /* misc */ "csum_partial_copy_generic", "__memcpy_mcsafe", + "mcsafe_handle_tail", "ftrace_likely_update", /* CONFIG_TRACE_BRANCH_PROFILING */ NULL };