From 6a35b18b3dcae75028c4fe2e53b9656acfee033c Mon Sep 17 00:00:00 2001 From: Andy Lutomirski Date: Sun, 28 Jan 2018 10:38:49 -0800 Subject: [PATCH] x86/entry/64: Push extra regs right away commit d1f7732009e0549eedf8ea1db948dc37be77fd46 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 Signed-off-by: Thomas Gleixner Acked-by: Ingo Molnar Cc: Borislav Petkov Cc: Linus Torvalds Cc: Kernel Hardening Link: https://lkml.kernel.org/r/462dff8d4d64dfbfc851fbf3130641809d980ecd.1517164461.git.luto@kernel.org Signed-off-by: Greg Kroah-Hartman --- arch/x86/entry/entry_64.S | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-) diff --git a/arch/x86/entry/entry_64.S b/arch/x86/entry/entry_64.S index c46c755f6e71..c752abe89d80 100644 --- a/arch/x86/entry/entry_64.S +++ b/arch/x86/entry/entry_64.S @@ -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 */