lk/linux-kernel-test
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

x86: early_idt_handler improvements, 64-bit

Browse Source 
It's not too pretty, but I found this made the "PANIC: early exception"
messages become much more reliably useful: 1. print the vector number,
2. print the %cs value, 3. handle error-code-pushing vs non-pushing vectors.

Signed-off-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This commit is contained in:
Roland McGrath
2008-01-30 13:33:06 +01:00
committed by Ingo Molnar
parent d504e39efd
commit 8866cd9dc9
3 changed files with 37 additions and 5 deletions
Download Patch File Download Diff File Expand all files Collapse all files

2
arch/x86/kernel/head64.c
View File

@@ -59,7 +59,7 @@ void __init x86_64_start_kernel(char * real_mode_data)
zap_identity_mappings(); zap_identity_mappings();
for (i = 0; i < IDT_ENTRIES; i++) for (i = 0; i < IDT_ENTRIES; i++)
set_intr_gate(i, early_idt_handler); set_intr_gate(i, &early_idt_handlers[i]);
load_idt((const struct desc_ptr *)&idt_descr); load_idt((const struct desc_ptr *)&idt_descr);
early_printk("Kernel alive\n"); early_printk("Kernel alive\n");

34
arch/x86/kernel/head_64.S
View File

@@ -267,14 +267,40 @@ init_rsp:
bad_address: bad_address:
jmp bad_address jmp bad_address
.macro early_idt_tramp first, last
.ifgt \last-\first
early_idt_tramp \first, \last-1
.endif
movl $\last,%esi
jmp early_idt_handler
.endm
.globl early_idt_handlers
early_idt_handlers:
early_idt_tramp 0, 63
early_idt_tramp 64, 127
early_idt_tramp 128, 191
early_idt_tramp 192, 255
ENTRY(early_idt_handler) ENTRY(early_idt_handler)
cmpl $2,early_recursion_flag(%rip) cmpl $2,early_recursion_flag(%rip)
jz 1f jz 1f
incl early_recursion_flag(%rip) incl early_recursion_flag(%rip)
xorl %eax,%eax
movq 8(%rsp),%rsi # get rip
movq (%rsp),%rdx
GET_CR2_INTO_RCX 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
xorl %eax,%eax
leaq early_idt_msg(%rip),%rdi leaq early_idt_msg(%rip),%rdi
call early_printk call early_printk
cmpl $2,early_recursion_flag(%rip) cmpl $2,early_recursion_flag(%rip)
@@ -291,7 +317,7 @@ early_recursion_flag:
.long 0 .long 0
early_idt_msg: early_idt_msg:
.asciz "PANIC: early exception rip %lx error %lx cr2 %lx\n" .asciz "PANIC: early exception %02lx rip %lx:%lx error %lx cr2 %lx\n"
early_idt_ripmsg: early_idt_ripmsg:
.asciz "RIP %s\n" .asciz "RIP %s\n"

6
include/asm-x86/segment.h
View File

@@ -195,4 +195,10 @@
#define GDT_ENTRY_TLS_ENTRIES 3 #define GDT_ENTRY_TLS_ENTRIES 3
#define TLS_SIZE (GDT_ENTRY_TLS_ENTRIES * 8) #define TLS_SIZE (GDT_ENTRY_TLS_ENTRIES * 8)
#ifdef __KERNEL__
#ifndef __ASSEMBLY__
extern const char early_idt_handlers[IDT_ENTRIES][10];
#endif
#endif
#endif #endif