luck/tmp_suning_uos_patched
1
0
Fork 1
Code Issues Pull Requests Packages Projects Releases Wiki Activity

x86/entry/64: Push extra regs right away

Browse Source 
With the fast path removed there is no point in splitting the push of the
normal and the extra register set. Just push the extra regs right away.

[ tglx: Split out from 'x86/entry/64: Remove the SYSCALL64 fast path' ]

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Ingo Molnar <mingo@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Kernel Hardening <kernel-hardening@lists.openwall.com>
Link: https://lkml.kernel.org/r/462dff8d4d64dfbfc851fbf3130641809d980ecd.1517164461.git.luto@kernel.org
This commit is contained in:
Andy Lutomirski 2018-01-28 10:38:49 -08:00 committed by Thomas Gleixner
parent 21d375b6b3
commit d1f7732009
1 changed files with 7 additions and 3 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

10
arch/x86/entry/entry_64.S
View File

@ -236,13 +236,17 @@ GLOBAL(entry_SYSCALL_64_after_hwframe)
pushq %r9 /* pt_regs->r9 */
pushq %r10 /* pt_regs->r10 */
pushq %r11 /* pt_regs->r11 */
sub $(6*8), %rsp /* pt_regs->bp, bx, r12-15 not saved */
UNWIND_HINT_REGS extra=0
pushq %rbx /* pt_regs->rbx */
pushq %rbp /* pt_regs->rbp */
pushq %r12 /* pt_regs->r12 */
pushq %r13 /* pt_regs->r13 */
pushq %r14 /* pt_regs->r14 */
pushq %r15 /* pt_regs->r15 */
UNWIND_HINT_REGS
TRACE_IRQS_OFF
/* IRQs are off. */
SAVE_EXTRA_REGS
movq %rsp, %rdi
call do_syscall_64 /* returns with IRQs disabled */