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authorLinus Torvalds <torvalds@linux-foundation.org>2012-12-11 19:55:20 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2012-12-11 19:55:20 -0800
commit0019fab3558c8c8135c88c3d38f24ab0a5408aa6 (patch)
treed51fe9edb3e05efe5089e3360510f513cccb6b0b /arch/x86/kernel
parentb64c5fda3868cb29d5dae0909561aa7d93fb7330 (diff)
parent6c8d8b3c69cef1330e0c5cbc2a8b9268024927a0 (diff)
Merge branch 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 asm changes from Ingo Molnar: "Two fixlets and a cleanup." * 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86_32: Return actual stack when requesting sp from regs x86: Don't clobber top of pt_regs in nested NMI x86/asm: Clean up copy_page_*() comments and code
Diffstat (limited to 'arch/x86/kernel')
-rw-r--r--arch/x86/kernel/entry_64.S41
1 files changed, 27 insertions, 14 deletions
diff --git a/arch/x86/kernel/entry_64.S b/arch/x86/kernel/entry_64.S
index 2a3806b95831..31b46128a63d 100644
--- a/arch/x86/kernel/entry_64.S
+++ b/arch/x86/kernel/entry_64.S
@@ -1699,9 +1699,10 @@ nested_nmi:
1:
/* Set up the interrupted NMIs stack to jump to repeat_nmi */
- leaq -6*8(%rsp), %rdx
+ leaq -1*8(%rsp), %rdx
movq %rdx, %rsp
- CFI_ADJUST_CFA_OFFSET 6*8
+ CFI_ADJUST_CFA_OFFSET 1*8
+ leaq -10*8(%rsp), %rdx
pushq_cfi $__KERNEL_DS
pushq_cfi %rdx
pushfq_cfi
@@ -1709,8 +1710,8 @@ nested_nmi:
pushq_cfi $repeat_nmi
/* Put stack back */
- addq $(11*8), %rsp
- CFI_ADJUST_CFA_OFFSET -11*8
+ addq $(6*8), %rsp
+ CFI_ADJUST_CFA_OFFSET -6*8
nested_nmi_out:
popq_cfi %rdx
@@ -1736,18 +1737,18 @@ first_nmi:
* +-------------------------+
* | NMI executing variable |
* +-------------------------+
- * | Saved SS |
- * | Saved Return RSP |
- * | Saved RFLAGS |
- * | Saved CS |
- * | Saved RIP |
- * +-------------------------+
* | copied SS |
* | copied Return RSP |
* | copied RFLAGS |
* | copied CS |
* | copied RIP |
* +-------------------------+
+ * | Saved SS |
+ * | Saved Return RSP |
+ * | Saved RFLAGS |
+ * | Saved CS |
+ * | Saved RIP |
+ * +-------------------------+
* | pt_regs |
* +-------------------------+
*
@@ -1763,9 +1764,14 @@ first_nmi:
/* Set the NMI executing variable on the stack. */
pushq_cfi $1
+ /*
+ * Leave room for the "copied" frame
+ */
+ subq $(5*8), %rsp
+
/* Copy the stack frame to the Saved frame */
.rept 5
- pushq_cfi 6*8(%rsp)
+ pushq_cfi 11*8(%rsp)
.endr
CFI_DEF_CFA_OFFSET SS+8-RIP
@@ -1786,12 +1792,15 @@ repeat_nmi:
* is benign for the non-repeat case, where 1 was pushed just above
* to this very stack slot).
*/
- movq $1, 5*8(%rsp)
+ movq $1, 10*8(%rsp)
/* Make another copy, this one may be modified by nested NMIs */
+ addq $(10*8), %rsp
+ CFI_ADJUST_CFA_OFFSET -10*8
.rept 5
- pushq_cfi 4*8(%rsp)
+ pushq_cfi -6*8(%rsp)
.endr
+ subq $(5*8), %rsp
CFI_DEF_CFA_OFFSET SS+8-RIP
end_repeat_nmi:
@@ -1842,8 +1851,12 @@ nmi_swapgs:
SWAPGS_UNSAFE_STACK
nmi_restore:
RESTORE_ALL 8
+
+ /* Pop the extra iret frame */
+ addq $(5*8), %rsp
+
/* Clear the NMI executing stack variable */
- movq $0, 10*8(%rsp)
+ movq $0, 5*8(%rsp)
jmp irq_return
CFI_ENDPROC
END(nmi)