x86/entry/64: Add instruction suffix to SYSRET

commit b2b1d94cdfd4e906d3936dab2850096a4a0c2017 upstream.

ignore_sysret() contains an unsuffixed SYSRET instruction. gas correctly
interprets this as SYSRETL, but leaving it up to gas to guess when there
is no register operand that implies a size is bad practice, and upstream
gas is likely to warn about this in the future. Use SYSRETL explicitly.
This does not change the assembled output.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Andy Lutomirski <luto@kernel.org>
Link: https://lkml.kernel.org/r/038a7c35-062b-a285-c6d2-653b56585844@suse.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/arch/x86/entry/entry_64.S b/arch/x86/entry/entry_64.S
index 3f418aedef8d7e9460d9fee505b26e8d7b017709..55e0538711387d037538236b211d3eab919a8d1e 100644 (file)
--- a/arch/x86/entry/entry_64.S
+++ b/arch/x86/entry/entry_64.S
@@ -1759,7 +1759,7 @@ END(nmi)
 ENTRY(ignore_sysret)
        UNWIND_HINT_EMPTY
        mov     $-ENOSYS, %eax
-       sysret
+       sysretl
 END(ignore_sysret)
 
 ENTRY(rewind_stack_do_exit)