git.ipfire.org Git - thirdparty/kernel/stable-queue.git/blob

   1 From 502af0d70843c2a9405d7ba1f79b4b0305aaf5f5 Mon Sep 17 00:00:00 2001
   2 From: Dominik Brodowski <linux@dominikbrodowski.net>
   3 Date: Sun, 11 Feb 2018 11:49:43 +0100
   4 Subject: x86/entry/64: Merge the POP_C_REGS and POP_EXTRA_REGS macros into a single POP_REGS macro
   5
   6 From: Dominik Brodowski <linux@dominikbrodowski.net>
   7
   8 commit 502af0d70843c2a9405d7ba1f79b4b0305aaf5f5 upstream.
   9
  10 The two special, opencoded cases for POP_C_REGS can be handled by ASM
  11 macros.
  12
  13 Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
  14 Cc: Andy Lutomirski <luto@kernel.org>
  15 Cc: Borislav Petkov <bp@alien8.de>
  16 Cc: Brian Gerst <brgerst@gmail.com>
  17 Cc: Denys Vlasenko <dvlasenk@redhat.com>
  18 Cc: H. Peter Anvin <hpa@zytor.com>
  19 Cc: Josh Poimboeuf <jpoimboe@redhat.com>
  20 Cc: Linus Torvalds <torvalds@linux-foundation.org>
  21 Cc: Peter Zijlstra <peterz@infradead.org>
  22 Cc: Thomas Gleixner <tglx@linutronix.de>
  23 Cc: dan.j.williams@intel.com
  24 Link: http://lkml.kernel.org/r/20180211104949.12992-3-linux@dominikbrodowski.net
  25 Signed-off-by: Ingo Molnar <mingo@kernel.org>
  26 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
  27
  28 ---
  29  arch/x86/entry/calling.h  |   15 +++++++++++----
  30  arch/x86/entry/entry_64.S |   26 ++++----------------------
  31  2 files changed, 15 insertions(+), 26 deletions(-)
  32
  33 --- a/arch/x86/entry/calling.h
  34 +++ b/arch/x86/entry/calling.h
  35 @@ -139,25 +139,32 @@ For 32-bit we have the following convent
  36         xorq %r15, %r15
  37         .endm
  38
  39 -       .macro POP_EXTRA_REGS
  40 +       .macro POP_REGS pop_rdi=1 skip_r11rcx=0
  41         popq %r15
  42         popq %r14
  43         popq %r13
  44         popq %r12
  45         popq %rbp
  46         popq %rbx
  47 -       .endm
  48 -
  49 -       .macro POP_C_REGS
  50 +       .if \skip_r11rcx
  51 +       popq %rsi
  52 +       .else
  53         popq %r11
  54 +       .endif
  55         popq %r10
  56         popq %r9
  57         popq %r8
  58         popq %rax
  59 +       .if \skip_r11rcx
  60 +       popq %rsi
  61 +       .else
  62         popq %rcx
  63 +       .endif
  64         popq %rdx
  65         popq %rsi
  66 +       .if \pop_rdi
  67         popq %rdi
  68 +       .endif
  69         .endm
  70
  71         .macro icebp
  72 --- a/arch/x86/entry/entry_64.S
  73 +++ b/arch/x86/entry/entry_64.S
  74 @@ -330,15 +330,7 @@ GLOBAL(entry_SYSCALL_64_after_hwframe)
  75  syscall_return_via_sysret:
  76         /* rcx and r11 are already restored (see code above) */
  77         UNWIND_HINT_EMPTY
  78 -       POP_EXTRA_REGS
  79 -       popq    %rsi    /* skip r11 */
  80 -       popq    %r10
  81 -       popq    %r9
  82 -       popq    %r8
  83 -       popq    %rax
  84 -       popq    %rsi    /* skip rcx */
  85 -       popq    %rdx
  86 -       popq    %rsi
  87 +       POP_REGS pop_rdi=0 skip_r11rcx=1
  88
  89         /*
  90          * Now all regs are restored except RSP and RDI.
  91 @@ -631,15 +623,7 @@ GLOBAL(swapgs_restore_regs_and_return_to
  92         ud2
  93  1:
  94  #endif
  95 -       POP_EXTRA_REGS
  96 -       popq    %r11
  97 -       popq    %r10
  98 -       popq    %r9
  99 -       popq    %r8
 100 -       popq    %rax
 101 -       popq    %rcx
 102 -       popq    %rdx
 103 -       popq    %rsi
 104 +       POP_REGS pop_rdi=0
 105
 106         /*
 107          * The stack is now user RDI, orig_ax, RIP, CS, EFLAGS, RSP, SS.
 108 @@ -697,8 +681,7 @@ GLOBAL(restore_regs_and_return_to_kernel
 109         ud2
 110  1:
 111  #endif
 112 -       POP_EXTRA_REGS
 113 -       POP_C_REGS
 114 +       POP_REGS
 115         addq    $8, %rsp        /* skip regs->orig_ax */
 116         INTERRUPT_RETURN
 117
 118 @@ -1655,8 +1638,7 @@ end_repeat_nmi:
 119  nmi_swapgs:
 120         SWAPGS_UNSAFE_STACK
 121  nmi_restore:
 122 -       POP_EXTRA_REGS
 123 -       POP_C_REGS
 124 +       POP_REGS
 125
 126         /*
 127          * Skip orig_ax and the "outermost" frame to point RSP at the "iret"