diff options
| author | Hugh Dickins <hughd@google.com> | 2017-09-21 20:39:56 -0700 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-01-05 15:44:24 +0100 |
| commit | 487f0b73d82611a2dc48d7d78409e2e9d994006a (patch) | |
| tree | 3b31aa0b5e59d6c547110e975ff04d125d915e67 /arch | |
| parent | d94df20135ccfdfb77b1479c501564e9b4ab5bc9 (diff) | |
kaiser: fix regs to do_nmi() ifndef CONFIG_KAISER
pjt has observed that nmi's second (nmi_from_kernel) call to do_nmi()
adjusted the %rdi regs arg, rightly when CONFIG_KAISER, but wrongly
when not CONFIG_KAISER.
Although the minimal change is to add an #ifdef CONFIG_KAISER around
the addq line, that looks cluttered, and I prefer how the first call
to do_nmi() handled it: prepare args in %rdi and %rsi before getting
into the CONFIG_KAISER block, since it does not touch them at all.
And while we're here, place the "#ifdef CONFIG_KAISER" that follows
each, to enclose the "Unconditionally restore CR3" comment: matching
how the "Unconditionally use kernel CR3" comment above is enclosed.
Signed-off-by: Hugh Dickins <hughd@google.com>
Acked-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/x86/entry/entry_64.S | 11 |
1 files changed, 6 insertions, 5 deletions
diff --git a/arch/x86/entry/entry_64.S b/arch/x86/entry/entry_64.S index 99bce319df0c..0942aa6d16a8 100644 --- a/arch/x86/entry/entry_64.S +++ b/arch/x86/entry/entry_64.S @@ -1297,12 +1297,13 @@ ENTRY(nmi) movq %rax, %cr3 #endif call do_nmi + +#ifdef CONFIG_KAISER /* * Unconditionally restore CR3. I know we return to * kernel code that needs user CR3, but do we ever return * to "user mode" where we need the kernel CR3? */ -#ifdef CONFIG_KAISER popq %rax mov %rax, %cr3 #endif @@ -1526,6 +1527,8 @@ end_repeat_nmi: SWAPGS xorl %ebx, %ebx 1: + movq %rsp, %rdi + movq $-1, %rsi #ifdef CONFIG_KAISER /* Unconditionally use kernel CR3 for do_nmi() */ /* %rax is saved above, so OK to clobber here */ @@ -1538,16 +1541,14 @@ end_repeat_nmi: #endif /* paranoidentry do_nmi, 0; without TRACE_IRQS_OFF */ - movq %rsp, %rdi - addq $8, %rdi /* point %rdi at ptregs, fixed up for CR3 */ - movq $-1, %rsi call do_nmi + +#ifdef CONFIG_KAISER /* * Unconditionally restore CR3. We might be returning to * kernel code that needs user CR3, like just just before * a sysret. */ -#ifdef CONFIG_KAISER popq %rax mov %rax, %cr3 #endif |