x86/head: Move the early NMI fixup into C
C is nicer than asm.
Tested-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: KVM list <kvm@vger.kernel.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: xen-devel <Xen-devel@lists.xen.org>
Link: http://lkml.kernel.org/r/dd068269f8d59fe44e9e43a50d0efd67da65c2b5.1459605520.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
diff --git a/arch/x86/kernel/head_32.S b/arch/x86/kernel/head_32.S
index 0904536..184291c 100644
--- a/arch/x86/kernel/head_32.S
+++ b/arch/x86/kernel/head_32.S
@@ -561,9 +561,6 @@
*/
cld
- cmpl $2,(%esp) # X86_TRAP_NMI
- je .Lis_nmi # Ignore NMI
-
cmpl $2,%ss:early_recursion_flag
je hlt_loop
incl %ss:early_recursion_flag
@@ -642,10 +639,6 @@
hlt_loop:
hlt
jmp hlt_loop
-
-.Lis_nmi:
- addl $8,%esp /* drop vector number and error code */
- iret
ENDPROC(early_idt_handler_common)
/* This is the default interrupt "handler" :-) */
diff --git a/arch/x86/kernel/head_64.S b/arch/x86/kernel/head_64.S
index 9e8636d..2308437 100644
--- a/arch/x86/kernel/head_64.S
+++ b/arch/x86/kernel/head_64.S
@@ -351,9 +351,6 @@
*/
cld
- cmpl $2,(%rsp) # X86_TRAP_NMI
- je .Lis_nmi # Ignore NMI
-
cmpl $2,early_recursion_flag(%rip)
jz 1f
incl early_recursion_flag(%rip)
@@ -422,9 +419,6 @@
20: /* Exception table entry found or page table generated */
decl early_recursion_flag(%rip)
jmp restore_regs_and_iret
-.Lis_nmi:
- addq $16,%rsp # drop vector number and error code
- INTERRUPT_RETURN
ENDPROC(early_idt_handler_common)
__INITDATA
diff --git a/arch/x86/mm/extable.c b/arch/x86/mm/extable.c
index 1366e06..4be0419 100644
--- a/arch/x86/mm/extable.c
+++ b/arch/x86/mm/extable.c
@@ -1,5 +1,6 @@
#include <linux/module.h>
#include <asm/uaccess.h>
+#include <asm/traps.h>
typedef bool (*ex_handler_t)(const struct exception_table_entry *,
struct pt_regs *, int);
@@ -89,6 +90,10 @@
unsigned long new_ip;
ex_handler_t handler;
+ /* Ignore early NMIs. */
+ if (trapnr == X86_TRAP_NMI)
+ return 1;
+
e = search_exception_tables(regs->ip);
if (!e)
return 0;