1 From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
2 From: Andy Lutomirski <luto@kernel.org>
3 Date: Thu, 2 Nov 2017 00:59:03 -0700
4 Subject: [PATCH] x86/entry/64: Use pop instead of movq in
5 syscall_return_via_sysret
7 Content-Type: text/plain; charset=UTF-8
8 Content-Transfer-Encoding: 8bit
14 Signed-off-by: Andy Lutomirski <luto@kernel.org>
15 Reviewed-by: Borislav Petkov <bp@suse.de>
16 Cc: Borislav Petkov <bpetkov@suse.de>
17 Cc: Brian Gerst <brgerst@gmail.com>
18 Cc: Dave Hansen <dave.hansen@intel.com>
19 Cc: Linus Torvalds <torvalds@linux-foundation.org>
20 Cc: Peter Zijlstra <peterz@infradead.org>
21 Cc: Thomas Gleixner <tglx@linutronix.de>
22 Link: http://lkml.kernel.org/r/6609b7f74ab31c36604ad746e019ea8495aec76c.1509609304.git.luto@kernel.org
23 Signed-off-by: Ingo Molnar <mingo@kernel.org>
24 (cherry picked from commit 4fbb39108f972437c44e5ffa781b56635d496826)
25 Signed-off-by: Andy Whitcroft <apw@canonical.com>
26 Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
27 (cherry picked from commit 1e9a9d5ef9f65eeb26eb8f0974dd3e693894baf1)
28 Signed-off-by: Fabian Grünbichler <f.gruenbichler@proxmox.com>
30 arch/x86/entry/entry_64.S | 14 +++++++++++---
31 1 file changed, 11 insertions(+), 3 deletions(-)
33 diff --git a/arch/x86/entry/entry_64.S b/arch/x86/entry/entry_64.S
34 index 6995f7e08aa1..33a416c7df2d 100644
35 --- a/arch/x86/entry/entry_64.S
36 +++ b/arch/x86/entry/entry_64.S
37 @@ -315,10 +315,18 @@ return_from_SYSCALL_64:
39 syscall_return_via_sysret:
40 /* rcx and r11 are already restored (see code above) */
42 - RESTORE_C_REGS_EXCEPT_RCX_R11
43 - movq RSP(%rsp), %rsp
46 + popq %rsi /* skip r11 */
51 + popq %rsi /* skip rcx */
55 + movq RSP-ORIG_RAX(%rsp), %rsp