forked from Minki/linux
x86: cosmetic fixes fault_{32|64}.c
First step towards unifying these files. - Checkpatch trailing whitespace fixes - Checkpatch indentation of switch statement fixes - Checkpatch single statement ifs need no braces fixes - Checkpatch consistent spacing after comma fixes - Introduce defines for pagefault error bits from X86_64 and add useful comment from X86_32. Use these defines in X86_32 where obvious. - Unify comments between 32|64 bit - Small ifdef movement for CONFIG_KPROBES in notify_page_fault() - Introduce X86_64 only case statement No Functional Changes. Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This commit is contained in:
Harvey Harrison
Ingo Molnar
parent
1d16b53e38
commit
33cb524383
@ -1,6 +1,4 @@
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/*
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* linux/arch/i386/mm/fault.c
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*
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* Copyright (C) 1995 Linus Torvalds
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*/
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@ -30,11 +28,25 @@
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#include <asm/desc.h>
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#include <asm/segment.h>
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extern void die(const char *,struct pt_regs *,long);
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/*
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* Page fault error code bits
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* bit 0 == 0 means no page found, 1 means protection fault
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* bit 1 == 0 means read, 1 means write
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* bit 2 == 0 means kernel, 1 means user-mode
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* bit 3 == 1 means use of reserved bit detected
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* bit 4 == 1 means fault was an instruction fetch
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*/
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#define PF_PROT (1<<0)
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#define PF_WRITE (1<<1)
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#define PF_USER (1<<2)
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#define PF_RSVD (1<<3)
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#define PF_INSTR (1<<4)
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extern void die(const char *, struct pt_regs *, long);
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#ifdef CONFIG_KPROBES
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static inline int notify_page_fault(struct pt_regs *regs)
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{
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#ifdef CONFIG_KPROBES
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int ret = 0;
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/* kprobe_running() needs smp_processor_id() */
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@ -46,13 +58,10 @@ static inline int notify_page_fault(struct pt_regs *regs)
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}
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return ret;
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}
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#else
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static inline int notify_page_fault(struct pt_regs *regs)
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{
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return 0;
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}
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#endif
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}
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/*
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* Return EIP plus the CS segment base. The segment limit is also
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@ -65,7 +74,7 @@ static inline int notify_page_fault(struct pt_regs *regs)
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* If CS is no longer a valid code segment, or if EIP is beyond the
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* limit, or if it is a kernel address when CS is not a kernel segment,
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* then the returned value will be greater than *eip_limit.
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*
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*
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* This is slow, but is very rarely executed.
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*/
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static inline unsigned long get_segment_eip(struct pt_regs *regs,
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@ -84,7 +93,7 @@ static inline unsigned long get_segment_eip(struct pt_regs *regs,
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/* The standard kernel/user address space limit. */
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*eip_limit = user_mode(regs) ? USER_DS.seg : KERNEL_DS.seg;
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/* By far the most common cases. */
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if (likely(SEGMENT_IS_FLAT_CODE(seg)))
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return ip;
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@ -99,7 +108,7 @@ static inline unsigned long get_segment_eip(struct pt_regs *regs,
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return 1; /* So that returned ip > *eip_limit. */
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}
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/* Get the GDT/LDT descriptor base.
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/* Get the GDT/LDT descriptor base.
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When you look for races in this code remember that
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LDT and other horrors are only used in user space. */
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if (seg & (1<<2)) {
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@ -109,16 +118,16 @@ static inline unsigned long get_segment_eip(struct pt_regs *regs,
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desc = (void *)desc + (seg & ~7);
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} else {
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/* Must disable preemption while reading the GDT. */
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desc = (u32 *)get_cpu_gdt_table(get_cpu());
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desc = (u32 *)get_cpu_gdt_table(get_cpu());
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desc = (void *)desc + (seg & ~7);
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}
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/* Decode the code segment base from the descriptor */
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base = get_desc_base((struct desc_struct *)desc);
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if (seg & (1<<2)) {
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if (seg & (1<<2))
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mutex_unlock(¤t->mm->context.lock);
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} else
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else
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put_cpu();
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/* Adjust EIP and segment limit, and clamp at the kernel limit.
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@ -129,19 +138,19 @@ static inline unsigned long get_segment_eip(struct pt_regs *regs,
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return ip + base;
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}
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/*
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/*
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* Sometimes AMD Athlon/Opteron CPUs report invalid exceptions on prefetch.
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* Check that here and ignore it.
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*/
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static int __is_prefetch(struct pt_regs *regs, unsigned long addr)
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{
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{
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unsigned long limit;
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unsigned char *instr = (unsigned char *)get_segment_eip (regs, &limit);
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unsigned char *instr = (unsigned char *)get_segment_eip(regs, &limit);
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int scan_more = 1;
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int prefetch = 0;
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int prefetch = 0;
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int i;
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for (i = 0; scan_more && i < 15; i++) {
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for (i = 0; scan_more && i < 15; i++) {
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unsigned char opcode;
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unsigned char instr_hi;
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unsigned char instr_lo;
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@ -149,27 +158,43 @@ static int __is_prefetch(struct pt_regs *regs, unsigned long addr)
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if (instr > (unsigned char *)limit)
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break;
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if (probe_kernel_address(instr, opcode))
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break;
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break;
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instr_hi = opcode & 0xf0;
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instr_lo = opcode & 0x0f;
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instr_hi = opcode & 0xf0;
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instr_lo = opcode & 0x0f;
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instr++;
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switch (instr_hi) {
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switch (instr_hi) {
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case 0x20:
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case 0x30:
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/* Values 0x26,0x2E,0x36,0x3E are valid x86 prefixes. */
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/*
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* Values 0x26,0x2E,0x36,0x3E are valid x86 prefixes.
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* In X86_64 long mode, the CPU will signal invalid
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* opcode if some of these prefixes are present so
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* X86_64 will never get here anyway
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*/
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scan_more = ((instr_lo & 7) == 0x6);
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break;
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#ifdef CONFIG_X86_64
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case 0x40:
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/*
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* In AMD64 long mode 0x40..0x4F are valid REX prefixes
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* Need to figure out under what instruction mode the
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* instruction was issued. Could check the LDT for lm,
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* but for now it's good enough to assume that long
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* mode only uses well known segments or kernel.
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*/
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scan_more = (!user_mode(regs)) || (regs->cs == __USER_CS);
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break;
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#endif
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case 0x60:
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/* 0x64 thru 0x67 are valid prefixes in all modes. */
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scan_more = (instr_lo & 0xC) == 0x4;
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break;
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break;
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case 0xF0:
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/* 0xF0, 0xF2, and 0xF3 are valid prefixes */
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/* 0xF0, 0xF2, 0xF3 are valid prefixes in all modes. */
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scan_more = !instr_lo || (instr_lo>>1) == 1;
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break;
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break;
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case 0x00:
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/* Prefetch instruction is 0x0F0D or 0x0F18 */
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scan_more = 0;
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@ -179,11 +204,11 @@ static int __is_prefetch(struct pt_regs *regs, unsigned long addr)
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break;
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prefetch = (instr_lo == 0xF) &&
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(opcode == 0x0D || opcode == 0x18);
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break;
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break;
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default:
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scan_more = 0;
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break;
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}
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}
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}
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return prefetch;
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}
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@ -199,7 +224,7 @@ static inline int is_prefetch(struct pt_regs *regs, unsigned long addr,
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return __is_prefetch(regs, addr);
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}
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return 0;
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}
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}
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static noinline void force_sig_info_fault(int si_signo, int si_code,
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unsigned long address, struct task_struct *tsk)
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@ -284,19 +309,12 @@ int show_unhandled_signals = 1;
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* This routine handles page faults. It determines the address,
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* and the problem, and then passes it off to one of the appropriate
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* routines.
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*
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* error_code:
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* bit 0 == 0 means no page found, 1 means protection fault
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* bit 1 == 0 means read, 1 means write
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* bit 2 == 0 means kernel, 1 means user-mode
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* bit 3 == 1 means use of reserved bit detected
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* bit 4 == 1 means fault was an instruction fetch
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*/
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void __kprobes do_page_fault(struct pt_regs *regs, unsigned long error_code)
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{
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struct task_struct *tsk;
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struct mm_struct *mm;
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struct vm_area_struct * vma;
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struct vm_area_struct *vma;
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unsigned long address;
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int write, si_code;
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int fault;
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@ -307,7 +325,7 @@ void __kprobes do_page_fault(struct pt_regs *regs, unsigned long error_code)
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trace_hardirqs_fixup();
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/* get the address */
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address = read_cr2();
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address = read_cr2();
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tsk = current;
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@ -350,7 +368,7 @@ void __kprobes do_page_fault(struct pt_regs *regs, unsigned long error_code)
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/*
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* If we're in an interrupt, have no user context or are running in an
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* atomic region then we must not take the fault..
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* atomic region then we must not take the fault.
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*/
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if (in_atomic() || !mm)
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goto bad_area_nosemaphore;
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@ -371,7 +389,7 @@ void __kprobes do_page_fault(struct pt_regs *regs, unsigned long error_code)
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* thus avoiding the deadlock.
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*/
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if (!down_read_trylock(&mm->mmap_sem)) {
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if ((error_code & 4) == 0 &&
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if ((error_code & PF_USER) == 0 &&
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!search_exception_tables(regs->ip))
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goto bad_area_nosemaphore;
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down_read(&mm->mmap_sem);
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@ -384,7 +402,7 @@ void __kprobes do_page_fault(struct pt_regs *regs, unsigned long error_code)
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goto good_area;
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if (!(vma->vm_flags & VM_GROWSDOWN))
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goto bad_area;
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if (error_code & 4) {
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if (error_code & PF_USER) {
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/*
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* Accessing the stack below %sp is always a bug.
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* The large cushion allows instructions like enter
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@ -403,19 +421,19 @@ void __kprobes do_page_fault(struct pt_regs *regs, unsigned long error_code)
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good_area:
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si_code = SEGV_ACCERR;
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write = 0;
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switch (error_code & 3) {
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default: /* 3: write, present */
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/* fall through */
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case 2: /* write, not present */
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if (!(vma->vm_flags & VM_WRITE))
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goto bad_area;
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write++;
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break;
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case 1: /* read, present */
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switch (error_code & (PF_PROT|PF_WRITE)) {
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default: /* 3: write, present */
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/* fall through */
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case PF_WRITE: /* write, not present */
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if (!(vma->vm_flags & VM_WRITE))
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goto bad_area;
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write++;
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break;
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case PF_PROT: /* read, present */
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goto bad_area;
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case 0: /* read, not present */
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if (!(vma->vm_flags & (VM_READ | VM_EXEC | VM_WRITE)))
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goto bad_area;
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case 0: /* read, not present */
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if (!(vma->vm_flags & (VM_READ | VM_EXEC | VM_WRITE)))
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goto bad_area;
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}
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survive:
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@ -457,14 +475,14 @@ bad_area:
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bad_area_nosemaphore:
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/* User mode accesses just cause a SIGSEGV */
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if (error_code & 4) {
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if (error_code & PF_USER) {
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/*
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* It's possible to have interrupts off here.
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*/
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local_irq_enable();
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/*
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* Valid to do another page fault here because this one came
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/*
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* Valid to do another page fault here because this one came
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* from user space.
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*/
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if (is_prefetch(regs, address, error_code))
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@ -492,7 +510,7 @@ bad_area_nosemaphore:
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*/
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if (boot_cpu_data.f00f_bug) {
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unsigned long nr;
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nr = (address - idt_descr.address) >> 3;
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if (nr == 6) {
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@ -507,13 +525,13 @@ no_context:
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if (fixup_exception(regs))
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return;
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/*
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/*
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* Valid to do another page fault here, because if this fault
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* had been triggered by is_prefetch fixup_exception would have
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* had been triggered by is_prefetch fixup_exception would have
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* handled it.
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*/
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if (is_prefetch(regs, address, error_code))
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return;
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if (is_prefetch(regs, address, error_code))
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return;
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/*
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* Oops. The kernel tried to access some bad page. We'll have to
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@ -541,7 +559,7 @@ no_context:
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else
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printk(KERN_ALERT "BUG: unable to handle kernel paging"
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" request");
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printk(" at virtual address %08lx\n",address);
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printk(" at virtual address %08lx\n", address);
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printk(KERN_ALERT "printing ip: %08lx ", regs->ip);
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page = read_cr3();
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@ -605,7 +623,7 @@ do_sigbus:
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up_read(&mm->mmap_sem);
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/* Kernel mode? Handle exceptions or die */
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if (!(error_code & 4))
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if (!(error_code & PF_USER))
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goto no_context;
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/* User space => ok to do another page fault */
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@ -1,6 +1,4 @@
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/*
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* linux/arch/x86-64/mm/fault.c
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*
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* Copyright (C) 1995 Linus Torvalds
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* Copyright (C) 2001,2002 Andi Kleen, SuSE Labs.
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*/
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@ -33,16 +31,23 @@
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#include <asm/proto.h>
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#include <asm-generic/sections.h>
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/* Page fault error code bits */
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#define PF_PROT (1<<0) /* or no page found */
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/*
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* Page fault error code bits
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* bit 0 == 0 means no page found, 1 means protection fault
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* bit 1 == 0 means read, 1 means write
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* bit 2 == 0 means kernel, 1 means user-mode
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* bit 3 == 1 means use of reserved bit detected
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* bit 4 == 1 means fault was an instruction fetch
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*/
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#define PF_PROT (1<<0)
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#define PF_WRITE (1<<1)
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#define PF_USER (1<<2)
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#define PF_RSVD (1<<3)
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#define PF_INSTR (1<<4)
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#ifdef CONFIG_KPROBES
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static inline int notify_page_fault(struct pt_regs *regs)
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{
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#ifdef CONFIG_KPROBES
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int ret = 0;
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/* kprobe_running() needs smp_processor_id() */
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@ -54,75 +59,75 @@ static inline int notify_page_fault(struct pt_regs *regs)
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}
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return ret;
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}
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#else
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static inline int notify_page_fault(struct pt_regs *regs)
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{
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return 0;
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}
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#endif
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}
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/* Sometimes the CPU reports invalid exceptions on prefetch.
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Check that here and ignore.
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Opcode checker based on code by Richard Brunner */
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static noinline int is_prefetch(struct pt_regs *regs, unsigned long addr,
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unsigned long error_code)
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{
|
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{
|
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unsigned char *instr;
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int scan_more = 1;
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int prefetch = 0;
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int prefetch = 0;
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unsigned char *max_instr;
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/* If it was a exec fault ignore */
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if (error_code & PF_INSTR)
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return 0;
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instr = (unsigned char __user *)convert_rip_to_linear(current, regs);
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max_instr = instr + 15;
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if (user_mode(regs) && instr >= (unsigned char *)TASK_SIZE)
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return 0;
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while (scan_more && instr < max_instr) {
|
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while (scan_more && instr < max_instr) {
|
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unsigned char opcode;
|
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unsigned char instr_hi;
|
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unsigned char instr_lo;
|
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|
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if (probe_kernel_address(instr, opcode))
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break;
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break;
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instr_hi = opcode & 0xf0;
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instr_lo = opcode & 0x0f;
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instr_hi = opcode & 0xf0;
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instr_lo = opcode & 0x0f;
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instr++;
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switch (instr_hi) {
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switch (instr_hi) {
|
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case 0x20:
|
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case 0x30:
|
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/* Values 0x26,0x2E,0x36,0x3E are valid x86
|
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prefixes. In long mode, the CPU will signal
|
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invalid opcode if some of these prefixes are
|
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present so we will never get here anyway */
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/*
|
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* Values 0x26,0x2E,0x36,0x3E are valid x86 prefixes.
|
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* In X86_64 long mode, the CPU will signal invalid
|
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* opcode if some of these prefixes are present so
|
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* X86_64 will never get here anyway
|
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*/
|
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scan_more = ((instr_lo & 7) == 0x6);
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break;
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#ifdef CONFIG_X86_64
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case 0x40:
|
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/* In AMD64 long mode, 0x40 to 0x4F are valid REX prefixes
|
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Need to figure out under what instruction mode the
|
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instruction was issued ... */
|
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/* Could check the LDT for lm, but for now it's good
|
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enough to assume that long mode only uses well known
|
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segments or kernel. */
|
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/*
|
||||
* In AMD64 long mode 0x40..0x4F are valid REX prefixes
|
||||
* Need to figure out under what instruction mode the
|
||||
* instruction was issued. Could check the LDT for lm,
|
||||
* but for now it's good enough to assume that long
|
||||
* mode only uses well known segments or kernel.
|
||||
*/
|
||||
scan_more = (!user_mode(regs)) || (regs->cs == __USER_CS);
|
||||
break;
|
||||
|
||||
#endif
|
||||
case 0x60:
|
||||
/* 0x64 thru 0x67 are valid prefixes in all modes. */
|
||||
scan_more = (instr_lo & 0xC) == 0x4;
|
||||
break;
|
||||
break;
|
||||
case 0xF0:
|
||||
/* 0xF0, 0xF2, and 0xF3 are valid prefixes in all modes. */
|
||||
scan_more = !instr_lo || (instr_lo>>1) == 1;
|
||||
break;
|
||||
break;
|
||||
case 0x00:
|
||||
/* Prefetch instruction is 0x0F0D or 0x0F18 */
|
||||
scan_more = 0;
|
||||
@ -130,20 +135,20 @@ static noinline int is_prefetch(struct pt_regs *regs, unsigned long addr,
|
||||
break;
|
||||
prefetch = (instr_lo == 0xF) &&
|
||||
(opcode == 0x0D || opcode == 0x18);
|
||||
break;
|
||||
break;
|
||||
default:
|
||||
scan_more = 0;
|
||||
break;
|
||||
}
|
||||
}
|
||||
}
|
||||
return prefetch;
|
||||
}
|
||||
|
||||
static int bad_address(void *p)
|
||||
{
|
||||
static int bad_address(void *p)
|
||||
{
|
||||
unsigned long dummy;
|
||||
return probe_kernel_address((unsigned long *)p, dummy);
|
||||
}
|
||||
}
|
||||
|
||||
void dump_pagetable(unsigned long address)
|
||||
{
|
||||
@ -154,11 +159,11 @@ void dump_pagetable(unsigned long address)
|
||||
|
||||
pgd = (pgd_t *)read_cr3();
|
||||
|
||||
pgd = __va((unsigned long)pgd & PHYSICAL_PAGE_MASK);
|
||||
pgd = __va((unsigned long)pgd & PHYSICAL_PAGE_MASK);
|
||||
pgd += pgd_index(address);
|
||||
if (bad_address(pgd)) goto bad;
|
||||
printk("PGD %lx ", pgd_val(*pgd));
|
||||
if (!pgd_present(*pgd)) goto ret;
|
||||
if (!pgd_present(*pgd)) goto ret;
|
||||
|
||||
pud = pud_offset(pgd, address);
|
||||
if (bad_address(pud)) goto bad;
|
||||
@ -172,7 +177,7 @@ void dump_pagetable(unsigned long address)
|
||||
|
||||
pte = pte_offset_kernel(pmd, address);
|
||||
if (bad_address(pte)) goto bad;
|
||||
printk("PTE %lx", pte_val(*pte));
|
||||
printk("PTE %lx", pte_val(*pte));
|
||||
ret:
|
||||
printk("\n");
|
||||
return;
|
||||
@ -180,7 +185,7 @@ bad:
|
||||
printk("BAD\n");
|
||||
}
|
||||
|
||||
static const char errata93_warning[] =
|
||||
static const char errata93_warning[] =
|
||||
KERN_ERR "******* Your BIOS seems to not contain a fix for K8 errata #93\n"
|
||||
KERN_ERR "******* Working around it, but it may cause SEGVs or burn power.\n"
|
||||
KERN_ERR "******* Please consider a BIOS update.\n"
|
||||
@ -188,31 +193,31 @@ KERN_ERR "******* Disabling USB legacy in the BIOS may also help.\n";
|
||||
|
||||
/* Workaround for K8 erratum #93 & buggy BIOS.
|
||||
BIOS SMM functions are required to use a specific workaround
|
||||
to avoid corruption of the 64bit RIP register on C stepping K8.
|
||||
A lot of BIOS that didn't get tested properly miss this.
|
||||
to avoid corruption of the 64bit RIP register on C stepping K8.
|
||||
A lot of BIOS that didn't get tested properly miss this.
|
||||
The OS sees this as a page fault with the upper 32bits of RIP cleared.
|
||||
Try to work around it here.
|
||||
Note we only handle faults in kernel here. */
|
||||
|
||||
static int is_errata93(struct pt_regs *regs, unsigned long address)
|
||||
static int is_errata93(struct pt_regs *regs, unsigned long address)
|
||||
{
|
||||
static int warned;
|
||||
if (address != regs->ip)
|
||||
return 0;
|
||||
if ((address >> 32) != 0)
|
||||
if ((address >> 32) != 0)
|
||||
return 0;
|
||||
address |= 0xffffffffUL << 32;
|
||||
if ((address >= (u64)_stext && address <= (u64)_etext) ||
|
||||
(address >= MODULES_VADDR && address <= MODULES_END)) {
|
||||
if ((address >= (u64)_stext && address <= (u64)_etext) ||
|
||||
(address >= MODULES_VADDR && address <= MODULES_END)) {
|
||||
if (!warned) {
|
||||
printk(errata93_warning);
|
||||
printk(errata93_warning);
|
||||
warned = 1;
|
||||
}
|
||||
regs->ip = address;
|
||||
return 1;
|
||||
}
|
||||
return 0;
|
||||
}
|
||||
}
|
||||
|
||||
static noinline void pgtable_bad(unsigned long address, struct pt_regs *regs,
|
||||
unsigned long error_code)
|
||||
@ -296,7 +301,7 @@ asmlinkage void __kprobes do_page_fault(struct pt_regs *regs,
|
||||
{
|
||||
struct task_struct *tsk;
|
||||
struct mm_struct *mm;
|
||||
struct vm_area_struct * vma;
|
||||
struct vm_area_struct *vma;
|
||||
unsigned long address;
|
||||
int write, fault;
|
||||
unsigned long flags;
|
||||
@ -360,8 +365,8 @@ asmlinkage void __kprobes do_page_fault(struct pt_regs *regs,
|
||||
pgtable_bad(address, regs, error_code);
|
||||
|
||||
/*
|
||||
* If we're in an interrupt or have no user
|
||||
* context, we must not take the fault..
|
||||
* If we're in an interrupt, have no user context or are running in an
|
||||
* atomic region then we must not take the fault.
|
||||
*/
|
||||
if (unlikely(in_atomic() || !mm))
|
||||
goto bad_area_nosemaphore;
|
||||
@ -403,7 +408,7 @@ asmlinkage void __kprobes do_page_fault(struct pt_regs *regs,
|
||||
goto good_area;
|
||||
if (!(vma->vm_flags & VM_GROWSDOWN))
|
||||
goto bad_area;
|
||||
if (error_code & 4) {
|
||||
if (error_code & PF_USER) {
|
||||
/* Allow userspace just enough access below the stack pointer
|
||||
* to let the 'enter' instruction work.
|
||||
*/
|
||||
@ -420,18 +425,18 @@ good_area:
|
||||
info.si_code = SEGV_ACCERR;
|
||||
write = 0;
|
||||
switch (error_code & (PF_PROT|PF_WRITE)) {
|
||||
default: /* 3: write, present */
|
||||
/* fall through */
|
||||
case PF_WRITE: /* write, not present */
|
||||
if (!(vma->vm_flags & VM_WRITE))
|
||||
goto bad_area;
|
||||
write++;
|
||||
break;
|
||||
case PF_PROT: /* read, present */
|
||||
default: /* 3: write, present */
|
||||
/* fall through */
|
||||
case PF_WRITE: /* write, not present */
|
||||
if (!(vma->vm_flags & VM_WRITE))
|
||||
goto bad_area;
|
||||
write++;
|
||||
break;
|
||||
case PF_PROT: /* read, present */
|
||||
goto bad_area;
|
||||
case 0: /* read, not present */
|
||||
if (!(vma->vm_flags & (VM_READ | VM_EXEC | VM_WRITE)))
|
||||
goto bad_area;
|
||||
case 0: /* read, not present */
|
||||
if (!(vma->vm_flags & (VM_READ | VM_EXEC | VM_WRITE)))
|
||||
goto bad_area;
|
||||
}
|
||||
|
||||
/*
|
||||
@ -491,7 +496,7 @@ bad_area_nosemaphore:
|
||||
tsk->comm, tsk->pid, address, regs->ip,
|
||||
regs->sp, error_code);
|
||||
}
|
||||
|
||||
|
||||
tsk->thread.cr2 = address;
|
||||
/* Kernel addresses are always protection faults */
|
||||
tsk->thread.error_code = error_code | (address >= TASK_SIZE);
|
||||
@ -505,21 +510,19 @@ bad_area_nosemaphore:
|
||||
}
|
||||
|
||||
no_context:
|
||||
|
||||
/* Are we prepared to handle this kernel fault? */
|
||||
if (fixup_exception(regs)) {
|
||||
if (fixup_exception(regs))
|
||||
return;
|
||||
}
|
||||
|
||||
/*
|
||||
/*
|
||||
* Hall of shame of CPU/BIOS bugs.
|
||||
*/
|
||||
|
||||
if (is_prefetch(regs, address, error_code))
|
||||
return;
|
||||
if (is_prefetch(regs, address, error_code))
|
||||
return;
|
||||
|
||||
if (is_errata93(regs, address))
|
||||
return;
|
||||
return;
|
||||
|
||||
/*
|
||||
* Oops. The kernel tried to access some bad page. We'll have to
|
||||
@ -532,7 +535,7 @@ no_context:
|
||||
printk(KERN_ALERT "Unable to handle kernel NULL pointer dereference");
|
||||
else
|
||||
printk(KERN_ALERT "Unable to handle kernel paging request");
|
||||
printk(" at %016lx RIP: \n" KERN_ALERT,address);
|
||||
printk(" at %016lx RIP: \n" KERN_ALERT, address);
|
||||
printk_address(regs->ip);
|
||||
dump_pagetable(address);
|
||||
tsk->thread.cr2 = address;
|
||||
@ -582,7 +585,7 @@ LIST_HEAD(pgd_list);
|
||||
|
||||
void vmalloc_sync_all(void)
|
||||
{
|
||||
/* Note that races in the updates of insync and start aren't
|
||||
/* Note that races in the updates of insync and start aren't
|
||||
problematic:
|
||||
insync can only get set bits added, and updates to start are only
|
||||
improving performance (without affecting correctness if undone). */
|
||||
@ -614,6 +617,6 @@ void vmalloc_sync_all(void)
|
||||
}
|
||||
/* Check that there is no need to do the same for the modules area. */
|
||||
BUILD_BUG_ON(!(MODULES_VADDR > __START_KERNEL));
|
||||
BUILD_BUG_ON(!(((MODULES_END - 1) & PGDIR_MASK) ==
|
||||
BUILD_BUG_ON(!(((MODULES_END - 1) & PGDIR_MASK) ==
|
||||
(__START_KERNEL & PGDIR_MASK)));
|
||||
}
|
||||
|
||||
Loading…
Reference in New Issue
Block a user