summaryrefslogtreecommitdiff
path: root/arch/x86/kernel/head_64.S
diff options
context:
space:
mode:
Diffstat (limited to 'arch/x86/kernel/head_64.S')
-rw-r--r--arch/x86/kernel/head_64.S80
1 files changed, 59 insertions, 21 deletions
diff --git a/arch/x86/kernel/head_64.S b/arch/x86/kernel/head_64.S
index 40f4eb3766d1..7a40f2447321 100644
--- a/arch/x86/kernel/head_64.S
+++ b/arch/x86/kernel/head_64.S
@@ -19,12 +19,15 @@
#include <asm/cache.h>
#include <asm/processor-flags.h>
#include <asm/percpu.h>
+#include <asm/nops.h>
#ifdef CONFIG_PARAVIRT
#include <asm/asm-offsets.h>
#include <asm/paravirt.h>
+#define GET_CR2_INTO(reg) GET_CR2_INTO_RAX ; movq %rax, reg
#else
-#define GET_CR2_INTO_RCX movq %cr2, %rcx
+#define GET_CR2_INTO(reg) movq %cr2, reg
+#define INTERRUPT_RETURN iretq
#endif
/* we are not able to switch in one step to the final KERNEL ADDRESS SPACE
@@ -270,36 +273,56 @@ bad_address:
jmp bad_address
.section ".init.text","ax"
-#ifdef CONFIG_EARLY_PRINTK
.globl early_idt_handlers
early_idt_handlers:
+ # 104(%rsp) %rflags
+ # 96(%rsp) %cs
+ # 88(%rsp) %rip
+ # 80(%rsp) error code
i = 0
.rept NUM_EXCEPTION_VECTORS
- movl $i, %esi
+ .if (EXCEPTION_ERRCODE_MASK >> i) & 1
+ ASM_NOP2
+ .else
+ pushq $0 # Dummy error code, to make stack frame uniform
+ .endif
+ pushq $i # 72(%rsp) Vector number
jmp early_idt_handler
i = i + 1
.endr
-#endif
ENTRY(early_idt_handler)
-#ifdef CONFIG_EARLY_PRINTK
+ cld
+
cmpl $2,early_recursion_flag(%rip)
jz 1f
incl early_recursion_flag(%rip)
- GET_CR2_INTO_RCX
- movq %rcx,%r9
- xorl %r8d,%r8d # zero for error code
- movl %esi,%ecx # get vector number
- # Test %ecx against mask of vectors that push error code.
- cmpl $31,%ecx
- ja 0f
- movl $1,%eax
- salq %cl,%rax
- testl $0x27d00,%eax
- je 0f
- popq %r8 # get error code
-0: movq 0(%rsp),%rcx # get ip
- movq 8(%rsp),%rdx # get cs
+
+ pushq %rax # 64(%rsp)
+ pushq %rcx # 56(%rsp)
+ pushq %rdx # 48(%rsp)
+ pushq %rsi # 40(%rsp)
+ pushq %rdi # 32(%rsp)
+ pushq %r8 # 24(%rsp)
+ pushq %r9 # 16(%rsp)
+ pushq %r10 # 8(%rsp)
+ pushq %r11 # 0(%rsp)
+
+ cmpl $__KERNEL_CS,96(%rsp)
+ jne 10f
+
+ leaq 88(%rsp),%rdi # Pointer to %rip
+ call early_fixup_exception
+ andl %eax,%eax
+ jnz 20f # Found an exception entry
+
+10:
+#ifdef CONFIG_EARLY_PRINTK
+ GET_CR2_INTO(%r9) # can clobber any volatile register if pv
+ movl 80(%rsp),%r8d # error code
+ movl 72(%rsp),%esi # vector number
+ movl 96(%rsp),%edx # %cs
+ movq 88(%rsp),%rcx # %rip
xorl %eax,%eax
leaq early_idt_msg(%rip),%rdi
call early_printk
@@ -308,17 +331,32 @@ ENTRY(early_idt_handler)
call dump_stack
#ifdef CONFIG_KALLSYMS
leaq early_idt_ripmsg(%rip),%rdi
- movq 0(%rsp),%rsi # get rip again
+ movq 40(%rsp),%rsi # %rip again
call __print_symbol
#endif
#endif /* EARLY_PRINTK */
1: hlt
jmp 1b
-#ifdef CONFIG_EARLY_PRINTK
+20: # Exception table entry found
+ popq %r11
+ popq %r10
+ popq %r9
+ popq %r8
+ popq %rdi
+ popq %rsi
+ popq %rdx
+ popq %rcx
+ popq %rax
+ addq $16,%rsp # drop vector number and error code
+ decl early_recursion_flag(%rip)
+ INTERRUPT_RETURN
+
+ .balign 4
early_recursion_flag:
.long 0
+#ifdef CONFIG_EARLY_PRINTK
early_idt_msg:
.asciz "PANIC: early exception %02lx rip %lx:%lx error %lx cr2 %lx\n"
early_idt_ripmsg: