Commit 16c8aa5b authored by Samuel Neves's avatar Samuel Neves Committed by Kleber Sacilotto de Souza

x86/vdso: Fix lsl operand order

BugLink: https://bugs.launchpad.net/bugs/1875905

commit e78e5a91 upstream.

In the __getcpu function, lsl is using the wrong target and destination
registers. Luckily, the compiler tends to choose %eax for both variables,
so it has been working so far.

Fixes: a582c540 ("x86/vdso: Use RDPID in preference to LSL when available")
Signed-off-by: default avatarSamuel Neves <sneves@dei.uc.pt>
Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
Acked-by: default avatarAndy Lutomirski <luto@kernel.org>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20180901201452.27828-1-sneves@dei.uc.ptSigned-off-by: default avatarNobuhiro Iwamatsu (CIP) <nobuhiro1.iwamatsu@toshiba.co.jp>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: default avatarIan May <ian.may@canonical.com>
Signed-off-by: default avatarKleber Sacilotto de Souza <kleber.souza@canonical.com>
parent 4be7abac
......@@ -86,7 +86,7 @@ static inline unsigned int __getcpu(void)
*
* If RDPID is available, use it.
*/
alternative_io ("lsl %[p],%[seg]",
alternative_io ("lsl %[seg],%[p]",
".byte 0xf3,0x0f,0xc7,0xf8", /* RDPID %eax/rax */
X86_FEATURE_RDPID,
[p] "=a" (p), [seg] "r" (__PER_CPU_SEG));
......
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