x86/uaccess: Fix up the fixup
authorPeter Zijlstra <peterz@infradead.org>
Wed, 3 Apr 2019 07:39:45 +0000 (09:39 +0200)
committerIngo Molnar <mingo@kernel.org>
Wed, 3 Apr 2019 07:39:45 +0000 (09:39 +0200)
New tooling got confused about this:

  arch/x86/lib/memcpy_64.o: warning: objtool: .fixup+0x7: return with UACCESS enabled

While the code isn't wrong, it is tedious (if at all possible) to
figure out what function a particular chunk of .fixup belongs to.

This then confuses the objtool uaccess validation. Instead of
returning directly from the .fixup, jump back into the right function.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
arch/x86/lib/memcpy_64.S

index 3b24dc05251c7ce908cc2be48befb971b5b8f564..9d05572370edc40f234f2813f5fc1c82020ad94f 100644 (file)
@@ -257,6 +257,7 @@ ENTRY(__memcpy_mcsafe)
        /* Copy successful. Return zero */
 .L_done_memcpy_trap:
        xorl %eax, %eax
+.L_done:
        ret
 ENDPROC(__memcpy_mcsafe)
 EXPORT_SYMBOL_GPL(__memcpy_mcsafe)
@@ -273,7 +274,7 @@ EXPORT_SYMBOL_GPL(__memcpy_mcsafe)
        addl    %edx, %ecx
 .E_trailing_bytes:
        mov     %ecx, %eax
-       ret
+       jmp     .L_done
 
        /*
         * For write fault handling, given the destination is unaligned,