On Thu, 25 Jul 2019, Josh Poimboeuf wrote:
Objtool reports:
drivers/gpu/drm/i915/gem/i915_gem_execbuffer.o: warning: objtool: .altinstr_replacement+0x36: redundant UACCESS disable
__copy_from_user() already does both STAC and CLAC, so the user_access_end() in its error path adds an extra unnecessary CLAC.
Fixes: 0b2c8f8b6b0c ("i915: fix missing user_access_end() in page fault exception case") Reported-by: Thomas Gleixner tglx@linutronix.de Reported-by: Sedat Dilek sedat.dilek@gmail.com Acked-by: Peter Zijlstra (Intel) peterz@infradead.org Tested-by: Nick Desaulniers ndesaulniers@google.com Tested-by: Sedat Dilek sedat.dilek@gmail.com Link: https://github.com/ClangBuiltLinux/linux/issues/617 Signed-off-by: Josh Poimboeuf jpoimboe@redhat.com
Reviewed-by: Thomas Gleixner tglx@linutronix.de