/*
* Copyright (C) 1995 Linus Torvalds
- * Copyright (C) 2001,2002 Andi Kleen, SuSE Labs.
+ * Copyright (C) 2001, 2002 Andi Kleen, SuSE Labs.
+ * Copyright (C) 2008-2009, Red Hat Inc., Ingo Molnar
*/
-
-#include <linux/signal.h>
-#include <linux/sched.h>
-#include <linux/kernel.h>
-#include <linux/errno.h>
-#include <linux/string.h>
-#include <linux/types.h>
-#include <linux/ptrace.h>
-#include <linux/mmiotrace.h>
-#include <linux/mman.h>
-#include <linux/mm.h>
-#include <linux/smp.h>
-#include <linux/interrupt.h>
-#include <linux/init.h>
-#include <linux/tty.h>
-#include <linux/vt_kern.h> /* For unblank_screen() */
-#include <linux/compiler.h>
-#include <linux/highmem.h>
-#include <linux/bootmem.h> /* for max_low_pfn */
-#include <linux/vmalloc.h>
-#include <linux/module.h>
-#include <linux/kprobes.h>
-#include <linux/uaccess.h>
-#include <linux/kdebug.h>
-#include <linux/magic.h>
-
-#include <asm/system.h>
-#include <asm/desc.h>
-#include <asm/segment.h>
-#include <asm/pgalloc.h>
-#include <asm/smp.h>
-#include <asm/tlbflush.h>
-#include <asm/proto.h>
-#include <asm-generic/sections.h>
-#include <asm/traps.h>
+#include <linux/magic.h> /* STACK_END_MAGIC */
+#include <linux/sched.h> /* test_thread_flag(), ... */
+#include <linux/kdebug.h> /* oops_begin/end, ... */
+#include <linux/module.h> /* search_exception_table */
+#include <linux/bootmem.h> /* max_low_pfn */
+#include <linux/kprobes.h> /* __kprobes, ... */
+#include <linux/mmiotrace.h> /* kmmio_handler, ... */
+#include <linux/perf_event.h> /* perf_sw_event */
+
+#include <asm/traps.h> /* dotraplinkage, ... */
+#include <asm/pgalloc.h> /* pgd_*(), ... */
+#include <asm/kmemcheck.h> /* kmemcheck_*(), ... */
/*
- * Page fault error code bits
- * bit 0 == 0 means no page found, 1 means protection fault
- * bit 1 == 0 means read, 1 means write
- * bit 2 == 0 means kernel, 1 means user-mode
- * bit 3 == 1 means use of reserved bit detected
- * bit 4 == 1 means fault was an instruction fetch
+ * Page fault error code bits:
+ *
+ * bit 0 == 0: no page found 1: protection fault
+ * bit 1 == 0: read access 1: write access
+ * bit 2 == 0: kernel-mode access 1: user-mode access
+ * bit 3 == 1: use of reserved bit detected
+ * bit 4 == 1: fault was an instruction fetch
*/
-#define PF_PROT (1<<0)
-#define PF_WRITE (1<<1)
-#define PF_USER (1<<2)
-#define PF_RSVD (1<<3)
-#define PF_INSTR (1<<4)
+enum x86_pf_error_code {
+
+ PF_PROT = 1 << 0,
+ PF_WRITE = 1 << 1,
+ PF_USER = 1 << 2,
+ PF_RSVD = 1 << 3,
+ PF_INSTR = 1 << 4,
+};
+/*
+ * Returns 0 if mmiotrace is disabled, or if the fault is not
+ * handled by mmiotrace:
+ */
static inline int kmmio_fault(struct pt_regs *regs, unsigned long addr)
{
-#ifdef CONFIG_MMIOTRACE
if (unlikely(is_kmmio_active()))
if (kmmio_handler(regs, addr) == 1)
return -1;
-#endif
return 0;
}
static inline int notify_page_fault(struct pt_regs *regs)
{
-#ifdef CONFIG_KPROBES
int ret = 0;
/* kprobe_running() needs smp_processor_id() */
- if (!user_mode_vm(regs)) {
+ if (kprobes_built_in() && !user_mode_vm(regs)) {
preempt_disable();
if (kprobe_running() && kprobe_fault_handler(regs, 14))
ret = 1;
}
return ret;
-#else
- return 0;
-#endif
}
/*
- * X86_32
- * Sometimes AMD Athlon/Opteron CPUs report invalid exceptions on prefetch.
- * Check that here and ignore it.
+ * Prefetch quirks:
+ *
+ * 32-bit mode:
*
- * X86_64
- * Sometimes the CPU reports invalid exceptions on prefetch.
- * Check that here and ignore it.
+ * Sometimes AMD Athlon/Opteron CPUs report invalid exceptions on prefetch.
+ * Check that here and ignore it.
*
- * Opcode checker based on code by Richard Brunner
+ * 64-bit mode:
+ *
+ * Sometimes the CPU reports invalid exceptions on prefetch.
+ * Check that here and ignore it.
+ *
+ * Opcode checker based on code by Richard Brunner.
*/
-static int is_prefetch(struct pt_regs *regs, unsigned long error_code,
- unsigned long addr)
+static inline int
+check_prefetch_opcode(struct pt_regs *regs, unsigned char *instr,
+ unsigned char opcode, int *prefetch)
+{
+ unsigned char instr_hi = opcode & 0xf0;
+ unsigned char instr_lo = opcode & 0x0f;
+
+ switch (instr_hi) {
+ case 0x20:
+ case 0x30:
+ /*
+ * Values 0x26,0x2E,0x36,0x3E are valid x86 prefixes.
+ * In X86_64 long mode, the CPU will signal invalid
+ * opcode if some of these prefixes are present so
+ * X86_64 will never get here anyway
+ */
+ return ((instr_lo & 7) == 0x6);
+#ifdef CONFIG_X86_64
+ case 0x40:
+ /*
+ * 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.
+ */
+ return (!user_mode(regs)) || (regs->cs == __USER_CS);
+#endif
+ case 0x60:
+ /* 0x64 thru 0x67 are valid prefixes in all modes. */
+ return (instr_lo & 0xC) == 0x4;
+ case 0xF0:
+ /* 0xF0, 0xF2, 0xF3 are valid prefixes in all modes. */
+ return !instr_lo || (instr_lo>>1) == 1;
+ case 0x00:
+ /* Prefetch instruction is 0x0F0D or 0x0F18 */
+ if (probe_kernel_address(instr, opcode))
+ return 0;
+
+ *prefetch = (instr_lo == 0xF) &&
+ (opcode == 0x0D || opcode == 0x18);
+ return 0;
+ default:
+ return 0;
+ }
+}
+
+static int
+is_prefetch(struct pt_regs *regs, unsigned long error_code, unsigned long addr)
{
+ unsigned char *max_instr;
unsigned char *instr;
- int scan_more = 1;
int prefetch = 0;
- unsigned char *max_instr;
/*
* If it was a exec (instruction fetch) fault on NX page, then
if (error_code & PF_INSTR)
return 0;
- instr = (unsigned char *)convert_ip_to_linear(current, regs);
+ instr = (void *)convert_ip_to_linear(current, regs);
max_instr = instr + 15;
if (user_mode(regs) && instr >= (unsigned char *)TASK_SIZE)
return 0;
- while (scan_more && instr < max_instr) {
+ while (instr < max_instr) {
unsigned char opcode;
- unsigned char instr_hi;
- unsigned char instr_lo;
if (probe_kernel_address(instr, opcode))
break;
- instr_hi = opcode & 0xf0;
- instr_lo = opcode & 0x0f;
instr++;
- switch (instr_hi) {
- case 0x20:
- case 0x30:
- /*
- * Values 0x26,0x2E,0x36,0x3E are valid x86 prefixes.
- * In X86_64 long mode, the CPU will signal invalid
- * opcode if some of these prefixes are present so
- * X86_64 will never get here anyway
- */
- scan_more = ((instr_lo & 7) == 0x6);
- break;
-#ifdef CONFIG_X86_64
- case 0x40:
- /*
- * 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;
- case 0xF0:
- /* 0xF0, 0xF2, 0xF3 are valid prefixes in all modes. */
- scan_more = !instr_lo || (instr_lo>>1) == 1;
- break;
- case 0x00:
- /* Prefetch instruction is 0x0F0D or 0x0F18 */
- scan_more = 0;
-
- if (probe_kernel_address(instr, opcode))
- break;
- prefetch = (instr_lo == 0xF) &&
- (opcode == 0x0D || opcode == 0x18);
+ if (!check_prefetch_opcode(regs, instr, opcode, &prefetch))
break;
- default:
- scan_more = 0;
- break;
- }
}
return prefetch;
}
-static void force_sig_info_fault(int si_signo, int si_code,
- unsigned long address, struct task_struct *tsk)
+static void
+force_sig_info_fault(int si_signo, int si_code, unsigned long address,
+ struct task_struct *tsk)
{
siginfo_t info;
- info.si_signo = si_signo;
- info.si_errno = 0;
- info.si_code = si_code;
- info.si_addr = (void __user *)address;
+ info.si_signo = si_signo;
+ info.si_errno = 0;
+ info.si_code = si_code;
+ info.si_addr = (void __user *)address;
+ info.si_addr_lsb = si_code == BUS_MCEERR_AR ? PAGE_SHIFT : 0;
+
force_sig_info(si_signo, &info, tsk);
}
-#ifdef CONFIG_X86_64
-static int bad_address(void *p)
+DEFINE_SPINLOCK(pgd_lock);
+LIST_HEAD(pgd_list);
+
+#ifdef CONFIG_X86_32
+static inline pmd_t *vmalloc_sync_one(pgd_t *pgd, unsigned long address)
{
- unsigned long dummy;
- return probe_kernel_address((unsigned long *)p, dummy);
+ unsigned index = pgd_index(address);
+ pgd_t *pgd_k;
+ pud_t *pud, *pud_k;
+ pmd_t *pmd, *pmd_k;
+
+ pgd += index;
+ pgd_k = init_mm.pgd + index;
+
+ if (!pgd_present(*pgd_k))
+ return NULL;
+
+ /*
+ * set_pgd(pgd, *pgd_k); here would be useless on PAE
+ * and redundant with the set_pmd() on non-PAE. As would
+ * set_pud.
+ */
+ pud = pud_offset(pgd, address);
+ pud_k = pud_offset(pgd_k, address);
+ if (!pud_present(*pud_k))
+ return NULL;
+
+ pmd = pmd_offset(pud, address);
+ pmd_k = pmd_offset(pud_k, address);
+ if (!pmd_present(*pmd_k))
+ return NULL;
+
+ if (!pmd_present(*pmd))
+ set_pmd(pmd, *pmd_k);
+ else
+ BUG_ON(pmd_page(*pmd) != pmd_page(*pmd_k));
+
+ return pmd_k;
+}
+
+void vmalloc_sync_all(void)
+{
+ unsigned long address;
+
+ if (SHARED_KERNEL_PMD)
+ return;
+
+ for (address = VMALLOC_START & PMD_MASK;
+ address >= TASK_SIZE && address < FIXADDR_TOP;
+ address += PMD_SIZE) {
+
+ unsigned long flags;
+ struct page *page;
+
+ spin_lock_irqsave(&pgd_lock, flags);
+ list_for_each_entry(page, &pgd_list, lru) {
+ if (!vmalloc_sync_one(page_address(page), address))
+ break;
+ }
+ spin_unlock_irqrestore(&pgd_lock, flags);
+ }
+}
+
+/*
+ * 32-bit:
+ *
+ * Handle a fault on the vmalloc or module mapping area
+ */
+static noinline int vmalloc_fault(unsigned long address)
+{
+ unsigned long pgd_paddr;
+ pmd_t *pmd_k;
+ pte_t *pte_k;
+
+ /* Make sure we are in vmalloc area: */
+ if (!(address >= VMALLOC_START && address < VMALLOC_END))
+ return -1;
+
+ /*
+ * Synchronize this task's top level page-table
+ * with the 'reference' page table.
+ *
+ * Do _not_ use "current" here. We might be inside
+ * an interrupt in the middle of a task switch..
+ */
+ pgd_paddr = read_cr3();
+ pmd_k = vmalloc_sync_one(__va(pgd_paddr), address);
+ if (!pmd_k)
+ return -1;
+
+ pte_k = pte_offset_kernel(pmd_k, address);
+ if (!pte_present(*pte_k))
+ return -1;
+
+ return 0;
+}
+
+/*
+ * Did it hit the DOS screen memory VA from vm86 mode?
+ */
+static inline void
+check_v8086_mode(struct pt_regs *regs, unsigned long address,
+ struct task_struct *tsk)
+{
+ unsigned long bit;
+
+ if (!v8086_mode(regs))
+ return;
+
+ bit = (address - 0xA0000) >> PAGE_SHIFT;
+ if (bit < 32)
+ tsk->thread.screen_bitmap |= 1 << bit;
+}
+
+static bool low_pfn(unsigned long pfn)
+{
+ return pfn < max_low_pfn;
}
-#endif
static void dump_pagetable(unsigned long address)
{
-#ifdef CONFIG_X86_32
- __typeof__(pte_val(__pte(0))) page;
+ pgd_t *base = __va(read_cr3());
+ pgd_t *pgd = &base[pgd_index(address)];
+ pmd_t *pmd;
+ pte_t *pte;
- page = read_cr3();
- page = ((__typeof__(page) *) __va(page))[address >> PGDIR_SHIFT];
#ifdef CONFIG_X86_PAE
- printk("*pdpt = %016Lx ", page);
- if ((page >> PAGE_SHIFT) < max_low_pfn
- && page & _PAGE_PRESENT) {
- page &= PAGE_MASK;
- page = ((__typeof__(page) *) __va(page))[(address >> PMD_SHIFT)
- & (PTRS_PER_PMD - 1)];
- printk(KERN_CONT "*pde = %016Lx ", page);
- page &= ~_PAGE_NX;
- }
-#else
- printk("*pde = %08lx ", page);
+ printk("*pdpt = %016Lx ", pgd_val(*pgd));
+ if (!low_pfn(pgd_val(*pgd) >> PAGE_SHIFT) || !pgd_present(*pgd))
+ goto out;
#endif
+ pmd = pmd_offset(pud_offset(pgd, address), address);
+ printk(KERN_CONT "*pde = %0*Lx ", sizeof(*pmd) * 2, (u64)pmd_val(*pmd));
/*
* We must not directly access the pte in the highpte
* case if the page table is located in highmem.
* And let's rather not kmap-atomic the pte, just in case
- * it's allocated already.
+ * it's allocated already:
*/
- if ((page >> PAGE_SHIFT) < max_low_pfn
- && (page & _PAGE_PRESENT)
- && !(page & _PAGE_PSE)) {
- page &= PAGE_MASK;
- page = ((__typeof__(page) *) __va(page))[(address >> PAGE_SHIFT)
- & (PTRS_PER_PTE - 1)];
- printk("*pte = %0*Lx ", sizeof(page)*2, (u64)page);
- }
+ if (!low_pfn(pmd_pfn(*pmd)) || !pmd_present(*pmd) || pmd_large(*pmd))
+ goto out;
+ pte = pte_offset_kernel(pmd, address);
+ printk("*pte = %0*Lx ", sizeof(*pte) * 2, (u64)pte_val(*pte));
+out:
printk("\n");
-#else /* CONFIG_X86_64 */
- pgd_t *pgd;
- pud_t *pud;
- pmd_t *pmd;
- pte_t *pte;
+}
- pgd = (pgd_t *)read_cr3();
+#else /* CONFIG_X86_64: */
- 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;
+void vmalloc_sync_all(void)
+{
+ unsigned long address;
- pud = pud_offset(pgd, address);
- if (bad_address(pud)) goto bad;
- printk("PUD %lx ", pud_val(*pud));
- if (!pud_present(*pud) || pud_large(*pud))
- goto ret;
+ for (address = VMALLOC_START & PGDIR_MASK; address <= VMALLOC_END;
+ address += PGDIR_SIZE) {
- pmd = pmd_offset(pud, address);
- if (bad_address(pmd)) goto bad;
- printk("PMD %lx ", pmd_val(*pmd));
- if (!pmd_present(*pmd) || pmd_large(*pmd)) goto ret;
+ const pgd_t *pgd_ref = pgd_offset_k(address);
+ unsigned long flags;
+ struct page *page;
- pte = pte_offset_kernel(pmd, address);
- if (bad_address(pte)) goto bad;
- printk("PTE %lx", pte_val(*pte));
-ret:
- printk("\n");
- return;
-bad:
- printk("BAD\n");
-#endif
+ if (pgd_none(*pgd_ref))
+ continue;
+
+ spin_lock_irqsave(&pgd_lock, flags);
+ list_for_each_entry(page, &pgd_list, lru) {
+ pgd_t *pgd;
+ pgd = (pgd_t *)page_address(page) + pgd_index(address);
+ if (pgd_none(*pgd))
+ set_pgd(pgd, *pgd_ref);
+ else
+ BUG_ON(pgd_page_vaddr(*pgd) != pgd_page_vaddr(*pgd_ref));
+ }
+ spin_unlock_irqrestore(&pgd_lock, flags);
+ }
}
-#ifdef CONFIG_X86_32
-static inline pmd_t *vmalloc_sync_one(pgd_t *pgd, unsigned long address)
+/*
+ * 64-bit:
+ *
+ * Handle a fault on the vmalloc area
+ *
+ * This assumes no large pages in there.
+ */
+static noinline int vmalloc_fault(unsigned long address)
{
- unsigned index = pgd_index(address);
- pgd_t *pgd_k;
- pud_t *pud, *pud_k;
- pmd_t *pmd, *pmd_k;
+ pgd_t *pgd, *pgd_ref;
+ pud_t *pud, *pud_ref;
+ pmd_t *pmd, *pmd_ref;
+ pte_t *pte, *pte_ref;
- pgd += index;
- pgd_k = init_mm.pgd + index;
+ /* Make sure we are in vmalloc area: */
+ if (!(address >= VMALLOC_START && address < VMALLOC_END))
+ return -1;
- if (!pgd_present(*pgd_k))
- return NULL;
+ /*
+ * Copy kernel mappings over when needed. This can also
+ * happen within a race in page table update. In the later
+ * case just flush:
+ */
+ pgd = pgd_offset(current->active_mm, address);
+ pgd_ref = pgd_offset_k(address);
+ if (pgd_none(*pgd_ref))
+ return -1;
+
+ if (pgd_none(*pgd))
+ set_pgd(pgd, *pgd_ref);
+ else
+ BUG_ON(pgd_page_vaddr(*pgd) != pgd_page_vaddr(*pgd_ref));
/*
- * set_pgd(pgd, *pgd_k); here would be useless on PAE
- * and redundant with the set_pmd() on non-PAE. As would
- * set_pud.
+ * Below here mismatches are bugs because these lower tables
+ * are shared:
*/
pud = pud_offset(pgd, address);
- pud_k = pud_offset(pgd_k, address);
- if (!pud_present(*pud_k))
- return NULL;
+ pud_ref = pud_offset(pgd_ref, address);
+ if (pud_none(*pud_ref))
+ return -1;
+
+ if (pud_none(*pud) || pud_page_vaddr(*pud) != pud_page_vaddr(*pud_ref))
+ BUG();
+
+ pmd = pmd_offset(pud, address);
+ pmd_ref = pmd_offset(pud_ref, address);
+ if (pmd_none(*pmd_ref))
+ return -1;
+
+ if (pmd_none(*pmd) || pmd_page(*pmd) != pmd_page(*pmd_ref))
+ BUG();
+
+ pte_ref = pte_offset_kernel(pmd_ref, address);
+ if (!pte_present(*pte_ref))
+ return -1;
+
+ pte = pte_offset_kernel(pmd, address);
+
+ /*
+ * Don't use pte_page here, because the mappings can point
+ * outside mem_map, and the NUMA hash lookup cannot handle
+ * that:
+ */
+ if (!pte_present(*pte) || pte_pfn(*pte) != pte_pfn(*pte_ref))
+ BUG();
+
+ return 0;
+}
+
+static const char errata93_warning[] =
+KERN_ERR
+"******* Your BIOS seems to not contain a fix for K8 errata #93\n"
+"******* Working around it, but it may cause SEGVs or burn power.\n"
+"******* Please consider a BIOS update.\n"
+"******* Disabling USB legacy in the BIOS may also help.\n";
+
+/*
+ * No vm86 mode in 64-bit mode:
+ */
+static inline void
+check_v8086_mode(struct pt_regs *regs, unsigned long address,
+ struct task_struct *tsk)
+{
+}
+
+static int bad_address(void *p)
+{
+ unsigned long dummy;
+
+ return probe_kernel_address((unsigned long *)p, dummy);
+}
+
+static void dump_pagetable(unsigned long address)
+{
+ pgd_t *base = __va(read_cr3() & PHYSICAL_PAGE_MASK);
+ pgd_t *pgd = base + pgd_index(address);
+ pud_t *pud;
+ pmd_t *pmd;
+ pte_t *pte;
+
+ if (bad_address(pgd))
+ goto bad;
+
+ printk("PGD %lx ", pgd_val(*pgd));
+
+ if (!pgd_present(*pgd))
+ goto out;
+
+ pud = pud_offset(pgd, address);
+ if (bad_address(pud))
+ goto bad;
+
+ printk("PUD %lx ", pud_val(*pud));
+ if (!pud_present(*pud) || pud_large(*pud))
+ goto out;
pmd = pmd_offset(pud, address);
- pmd_k = pmd_offset(pud_k, address);
- if (!pmd_present(*pmd_k))
- return NULL;
- if (!pmd_present(*pmd)) {
- set_pmd(pmd, *pmd_k);
- arch_flush_lazy_mmu_mode();
- } else
- BUG_ON(pmd_page(*pmd) != pmd_page(*pmd_k));
- return pmd_k;
+ if (bad_address(pmd))
+ goto bad;
+
+ printk("PMD %lx ", pmd_val(*pmd));
+ if (!pmd_present(*pmd) || pmd_large(*pmd))
+ goto out;
+
+ pte = pte_offset_kernel(pmd, address);
+ if (bad_address(pte))
+ goto bad;
+
+ printk("PTE %lx", pte_val(*pte));
+out:
+ printk("\n");
+ return;
+bad:
+ printk("BAD\n");
}
-#endif
-#ifdef CONFIG_X86_64
-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"
-KERN_ERR "******* Disabling USB legacy in the BIOS may also help.\n";
-#endif
+#endif /* CONFIG_X86_64 */
-/* 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.
- 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.
- Does nothing for X86_32
+/*
+ * 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.
+ *
+ * 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.
+ * Does nothing on 32-bit.
*/
static int is_errata93(struct pt_regs *regs, unsigned long address)
{
#ifdef CONFIG_X86_64
- static int warned;
if (address != regs->ip)
return 0;
+
if ((address >> 32) != 0)
return 0;
+
address |= 0xffffffffUL << 32;
if ((address >= (u64)_stext && address <= (u64)_etext) ||
(address >= MODULES_VADDR && address <= MODULES_END)) {
- if (!warned) {
- printk(errata93_warning);
- warned = 1;
- }
+ printk_once(errata93_warning);
regs->ip = address;
return 1;
}
}
/*
- * Work around K8 erratum #100 K8 in compat mode occasionally jumps to illegal
- * addresses >4GB. We catch this in the page fault handler because these
- * addresses are not reachable. Just detect this case and return. Any code
+ * Work around K8 erratum #100 K8 in compat mode occasionally jumps
+ * to illegal addresses >4GB.
+ *
+ * We catch this in the page fault handler because these addresses
+ * are not reachable. Just detect this case and return. Any code
* segment in LDT is compatibility mode.
*/
static int is_errata100(struct pt_regs *regs, unsigned long address)
{
#ifdef CONFIG_X86_64
- if ((regs->cs == __USER32_CS || (regs->cs & (1<<2))) &&
- (address >> 32))
+ if ((regs->cs == __USER32_CS || (regs->cs & (1<<2))) && (address >> 32))
return 1;
#endif
return 0;
{
#ifdef CONFIG_X86_F00F_BUG
unsigned long nr;
+
/*
- * Pentium F0 0F C7 C8 bug workaround.
+ * Pentium F0 0F C7 C8 bug workaround:
*/
if (boot_cpu_data.f00f_bug) {
nr = (address - idt_descr.address) >> 3;
return 0;
}
-static void show_fault_oops(struct pt_regs *regs, unsigned long error_code,
- unsigned long address)
+static const char nx_warning[] = KERN_CRIT
+"kernel tried to execute NX-protected page - exploit attempt? (uid: %d)\n";
+
+static void
+show_fault_oops(struct pt_regs *regs, unsigned long error_code,
+ unsigned long address)
{
-#ifdef CONFIG_X86_32
if (!oops_may_print())
return;
-#endif
-#ifdef CONFIG_X86_PAE
if (error_code & PF_INSTR) {
unsigned int level;
+
pte_t *pte = lookup_address(address, &level);
if (pte && pte_present(*pte) && !pte_exec(*pte))
- printk(KERN_CRIT "kernel tried to execute "
- "NX-protected page - exploit attempt? "
- "(uid: %d)\n", current_uid());
+ printk(nx_warning, current_uid());
}
-#endif
printk(KERN_ALERT "BUG: unable to handle kernel ");
if (address < PAGE_SIZE)
printk(KERN_CONT "NULL pointer dereference");
else
printk(KERN_CONT "paging request");
+
printk(KERN_CONT " at %p\n", (void *) address);
printk(KERN_ALERT "IP:");
printk_address(regs->ip, 1);
+
dump_pagetable(address);
}
-#ifdef CONFIG_X86_64
-static noinline void pgtable_bad(struct pt_regs *regs,
- unsigned long error_code, unsigned long address)
+static noinline void
+pgtable_bad(struct pt_regs *regs, unsigned long error_code,
+ unsigned long address)
{
- unsigned long flags = oops_begin();
- int sig = SIGKILL;
- struct task_struct *tsk = current;
+ struct task_struct *tsk;
+ unsigned long flags;
+ int sig;
+
+ flags = oops_begin();
+ tsk = current;
+ sig = SIGKILL;
printk(KERN_ALERT "%s: Corrupted page table at address %lx\n",
tsk->comm, address);
dump_pagetable(address);
- tsk = current;
- tsk->thread.cr2 = address;
- tsk->thread.trap_no = 14;
- tsk->thread.error_code = error_code;
+
+ tsk->thread.cr2 = address;
+ tsk->thread.trap_no = 14;
+ tsk->thread.error_code = error_code;
+
if (__die("Bad pagetable", regs, error_code))
sig = 0;
+
oops_end(flags, regs, sig);
}
-#endif
-static noinline void no_context(struct pt_regs *regs,
- unsigned long error_code, unsigned long address)
+static noinline void
+no_context(struct pt_regs *regs, unsigned long error_code,
+ unsigned long address)
{
struct task_struct *tsk = current;
unsigned long *stackend;
-
-#ifdef CONFIG_X86_64
unsigned long flags;
int sig;
-#endif
- /* Are we prepared to handle this kernel fault? */
+ /* Are we prepared to handle this kernel fault? */
if (fixup_exception(regs))
return;
/*
- * X86_32
- * Valid to do another page fault here, because if this fault
- * had been triggered by is_prefetch fixup_exception would have
- * handled it.
+ * 32-bit:
*
- * X86_64
- * Hall of shame of CPU/BIOS bugs.
+ * Valid to do another page fault here, because if this fault
+ * had been triggered by is_prefetch fixup_exception would have
+ * handled it.
+ *
+ * 64-bit:
+ *
+ * Hall of shame of CPU/BIOS bugs.
*/
if (is_prefetch(regs, error_code, address))
return;
/*
* Oops. The kernel tried to access some bad page. We'll have to
- * terminate things with extreme prejudice.
+ * terminate things with extreme prejudice:
*/
-#ifdef CONFIG_X86_32
- bust_spinlocks(1);
-#else
flags = oops_begin();
-#endif
show_fault_oops(regs, error_code, address);
- stackend = end_of_stack(tsk);
+ stackend = end_of_stack(tsk);
if (*stackend != STACK_END_MAGIC)
printk(KERN_ALERT "Thread overran stack, or stack corrupted\n");
- tsk->thread.cr2 = address;
- tsk->thread.trap_no = 14;
- tsk->thread.error_code = error_code;
+ tsk->thread.cr2 = address;
+ tsk->thread.trap_no = 14;
+ tsk->thread.error_code = error_code;
-#ifdef CONFIG_X86_32
- die("Oops", regs, error_code);
- bust_spinlocks(0);
- do_exit(SIGKILL);
-#else
sig = SIGKILL;
if (__die("Oops", regs, error_code))
sig = 0;
+
/* Executive summary in case the body of the oops scrolled away */
printk(KERN_EMERG "CR2: %016lx\n", address);
+
oops_end(flags, regs, sig);
-#endif
}
-static void __bad_area_nosemaphore(struct pt_regs *regs,
- unsigned long error_code, unsigned long address,
- int si_code)
+/*
+ * Print out info about fatal segfaults, if the show_unhandled_signals
+ * sysctl is set:
+ */
+static inline void
+show_signal_msg(struct pt_regs *regs, unsigned long error_code,
+ unsigned long address, struct task_struct *tsk)
+{
+ if (!unhandled_signal(tsk, SIGSEGV))
+ return;
+
+ if (!printk_ratelimit())
+ return;
+
+ printk("%s%s[%d]: segfault at %lx ip %p sp %p error %lx",
+ task_pid_nr(tsk) > 1 ? KERN_INFO : KERN_EMERG,
+ tsk->comm, task_pid_nr(tsk), address,
+ (void *)regs->ip, (void *)regs->sp, error_code);
+
+ print_vma_addr(KERN_CONT " in ", regs->ip);
+
+ printk(KERN_CONT "\n");
+}
+
+static void
+__bad_area_nosemaphore(struct pt_regs *regs, unsigned long error_code,
+ unsigned long address, int si_code)
{
struct task_struct *tsk = current;
/* User mode accesses just cause a SIGSEGV */
if (error_code & PF_USER) {
/*
- * It's possible to have interrupts off here.
+ * It's possible to have interrupts off here:
*/
local_irq_enable();
/*
* Valid to do another page fault here because this one came
- * from user space.
+ * from user space:
*/
if (is_prefetch(regs, error_code, address))
return;
if (is_errata100(regs, address))
return;
- if (show_unhandled_signals && unhandled_signal(tsk, SIGSEGV) &&
- printk_ratelimit()) {
- printk(
- "%s%s[%d]: segfault at %lx ip %p sp %p error %lx",
- task_pid_nr(tsk) > 1 ? KERN_INFO : KERN_EMERG,
- tsk->comm, task_pid_nr(tsk), address,
- (void *) regs->ip, (void *) regs->sp, error_code);
- print_vma_addr(" in ", regs->ip);
- printk("\n");
- }
+ if (unlikely(show_unhandled_signals))
+ show_signal_msg(regs, error_code, address, tsk);
+
+ /* Kernel addresses are always protection faults: */
+ tsk->thread.cr2 = address;
+ tsk->thread.error_code = error_code | (address >= TASK_SIZE);
+ tsk->thread.trap_no = 14;
- tsk->thread.cr2 = address;
- /* Kernel addresses are always protection faults */
- tsk->thread.error_code = error_code | (address >= TASK_SIZE);
- tsk->thread.trap_no = 14;
force_sig_info_fault(SIGSEGV, si_code, address, tsk);
+
return;
}
no_context(regs, error_code, address);
}
-static noinline void bad_area_nosemaphore(struct pt_regs *regs,
- unsigned long error_code, unsigned long address)
+static noinline void
+bad_area_nosemaphore(struct pt_regs *regs, unsigned long error_code,
+ unsigned long address)
{
__bad_area_nosemaphore(regs, error_code, address, SEGV_MAPERR);
}
-static void __bad_area(struct pt_regs *regs,
- unsigned long error_code, unsigned long address,
- int si_code)
+static void
+__bad_area(struct pt_regs *regs, unsigned long error_code,
+ unsigned long address, int si_code)
{
struct mm_struct *mm = current->mm;
__bad_area_nosemaphore(regs, error_code, address, si_code);
}
-static noinline void bad_area(struct pt_regs *regs,
- unsigned long error_code, unsigned long address)
+static noinline void
+bad_area(struct pt_regs *regs, unsigned long error_code, unsigned long address)
{
__bad_area(regs, error_code, address, SEGV_MAPERR);
}
-static noinline void bad_area_access_error(struct pt_regs *regs,
- unsigned long error_code, unsigned long address)
+static noinline void
+bad_area_access_error(struct pt_regs *regs, unsigned long error_code,
+ unsigned long address)
{
__bad_area(regs, error_code, address, SEGV_ACCERR);
}
/* TODO: fixup for "mm-invoke-oom-killer-from-page-fault.patch" */
-static void out_of_memory(struct pt_regs *regs,
- unsigned long error_code, unsigned long address)
+static void
+out_of_memory(struct pt_regs *regs, unsigned long error_code,
+ unsigned long address)
{
/*
* We ran out of memory, call the OOM killer, and return the userspace
- * (which will retry the fault, or kill us if we got oom-killed).
+ * (which will retry the fault, or kill us if we got oom-killed):
*/
up_read(¤t->mm->mmap_sem);
+
pagefault_out_of_memory();
}
-static void do_sigbus(struct pt_regs *regs,
- unsigned long error_code, unsigned long address)
+static void
+do_sigbus(struct pt_regs *regs, unsigned long error_code, unsigned long address,
+ unsigned int fault)
{
struct task_struct *tsk = current;
struct mm_struct *mm = tsk->mm;
+ int code = BUS_ADRERR;
up_read(&mm->mmap_sem);
- /* Kernel mode? Handle exceptions or die */
+ /* Kernel mode? Handle exceptions or die: */
if (!(error_code & PF_USER))
no_context(regs, error_code, address);
-#ifdef CONFIG_X86_32
- /* User space => ok to do another page fault */
+
+ /* User-space => ok to do another page fault: */
if (is_prefetch(regs, error_code, address))
return;
+
+ tsk->thread.cr2 = address;
+ tsk->thread.error_code = error_code;
+ tsk->thread.trap_no = 14;
+
+#ifdef CONFIG_MEMORY_FAILURE
+ if (fault & VM_FAULT_HWPOISON) {
+ printk(KERN_ERR
+ "MCE: Killing %s:%d due to hardware memory corruption fault at %lx\n",
+ tsk->comm, tsk->pid, address);
+ code = BUS_MCEERR_AR;
+ }
#endif
- tsk->thread.cr2 = address;
- tsk->thread.error_code = error_code;
- tsk->thread.trap_no = 14;
- force_sig_info_fault(SIGBUS, BUS_ADRERR, address, tsk);
+ force_sig_info_fault(SIGBUS, code, address, tsk);
}
-static noinline void mm_fault_error(struct pt_regs *regs,
- unsigned long error_code, unsigned long address, unsigned int fault)
+static noinline void
+mm_fault_error(struct pt_regs *regs, unsigned long error_code,
+ unsigned long address, unsigned int fault)
{
- if (fault & VM_FAULT_OOM)
+ if (fault & VM_FAULT_OOM) {
out_of_memory(regs, error_code, address);
- else if (fault & VM_FAULT_SIGBUS)
- do_sigbus(regs, error_code, address);
- else
- BUG();
+ } else {
+ if (fault & (VM_FAULT_SIGBUS|VM_FAULT_HWPOISON))
+ do_sigbus(regs, error_code, address, fault);
+ else
+ BUG();
+ }
}
static int spurious_fault_check(unsigned long error_code, pte_t *pte)
{
if ((error_code & PF_WRITE) && !pte_write(*pte))
return 0;
+
if ((error_code & PF_INSTR) && !pte_exec(*pte))
return 0;
}
/*
- * Handle a spurious fault caused by a stale TLB entry. This allows
- * us to lazily refresh the TLB when increasing the permissions of a
- * kernel page (RO -> RW or NX -> X). Doing it eagerly is very
- * expensive since that implies doing a full cross-processor TLB
- * flush, even if no stale TLB entries exist on other processors.
+ * Handle a spurious fault caused by a stale TLB entry.
+ *
+ * This allows us to lazily refresh the TLB when increasing the
+ * permissions of a kernel page (RO -> RW or NX -> X). Doing it
+ * eagerly is very expensive since that implies doing a full
+ * cross-processor TLB flush, even if no stale TLB entries exist
+ * on other processors.
+ *
* There are no security implications to leaving a stale TLB when
* increasing the permissions on a page.
*/
-static noinline int spurious_fault(unsigned long error_code,
- unsigned long address)
+static noinline int
+spurious_fault(unsigned long error_code, unsigned long address)
{
pgd_t *pgd;
pud_t *pud;
pmd_t *pmd;
pte_t *pte;
+ int ret;
/* Reserved-bit violation or user access to kernel space? */
if (error_code & (PF_USER | PF_RSVD))
if (!pte_present(*pte))
return 0;
- return spurious_fault_check(error_code, pte);
-}
-
-/*
- * X86_32
- * Handle a fault on the vmalloc or module mapping area
- *
- * X86_64
- * Handle a fault on the vmalloc area
- *
- * This assumes no large pages in there.
- */
-static noinline int vmalloc_fault(unsigned long address)
-{
-#ifdef CONFIG_X86_32
- unsigned long pgd_paddr;
- pmd_t *pmd_k;
- pte_t *pte_k;
-
- /* Make sure we are in vmalloc area */
- if (!(address >= VMALLOC_START && address < VMALLOC_END))
- return -1;
+ ret = spurious_fault_check(error_code, pte);
+ if (!ret)
+ return 0;
/*
- * Synchronize this task's top level page-table
- * with the 'reference' page table.
- *
- * Do _not_ use "current" here. We might be inside
- * an interrupt in the middle of a task switch..
+ * Make sure we have permissions in PMD.
+ * If not, then there's a bug in the page tables:
*/
- pgd_paddr = read_cr3();
- pmd_k = vmalloc_sync_one(__va(pgd_paddr), address);
- if (!pmd_k)
- return -1;
- pte_k = pte_offset_kernel(pmd_k, address);
- if (!pte_present(*pte_k))
- return -1;
- return 0;
-#else
- pgd_t *pgd, *pgd_ref;
- pud_t *pud, *pud_ref;
- pmd_t *pmd, *pmd_ref;
- pte_t *pte, *pte_ref;
-
- /* Make sure we are in vmalloc area */
- if (!(address >= VMALLOC_START && address < VMALLOC_END))
- return -1;
-
- /* Copy kernel mappings over when needed. This can also
- happen within a race in page table update. In the later
- case just flush. */
-
- pgd = pgd_offset(current->active_mm, address);
- pgd_ref = pgd_offset_k(address);
- if (pgd_none(*pgd_ref))
- return -1;
- if (pgd_none(*pgd))
- set_pgd(pgd, *pgd_ref);
- else
- BUG_ON(pgd_page_vaddr(*pgd) != pgd_page_vaddr(*pgd_ref));
+ ret = spurious_fault_check(error_code, (pte_t *) pmd);
+ WARN_ONCE(!ret, "PMD has incorrect permission bits\n");
- /* Below here mismatches are bugs because these lower tables
- are shared */
-
- pud = pud_offset(pgd, address);
- pud_ref = pud_offset(pgd_ref, address);
- if (pud_none(*pud_ref))
- return -1;
- if (pud_none(*pud) || pud_page_vaddr(*pud) != pud_page_vaddr(*pud_ref))
- BUG();
- pmd = pmd_offset(pud, address);
- pmd_ref = pmd_offset(pud_ref, address);
- if (pmd_none(*pmd_ref))
- return -1;
- if (pmd_none(*pmd) || pmd_page(*pmd) != pmd_page(*pmd_ref))
- BUG();
- pte_ref = pte_offset_kernel(pmd_ref, address);
- if (!pte_present(*pte_ref))
- return -1;
- pte = pte_offset_kernel(pmd, address);
- /* Don't use pte_page here, because the mappings can point
- outside mem_map, and the NUMA hash lookup cannot handle
- that. */
- if (!pte_present(*pte) || pte_pfn(*pte) != pte_pfn(*pte_ref))
- BUG();
- return 0;
-#endif
+ return ret;
}
int show_unhandled_signals = 1;
-static inline int access_error(unsigned long error_code, int write,
- struct vm_area_struct *vma)
+static inline int
+access_error(unsigned long error_code, int write, struct vm_area_struct *vma)
{
if (write) {
- /* write, present and write, not present */
+ /* write, present and write, not present: */
if (unlikely(!(vma->vm_flags & VM_WRITE)))
return 1;
- } else if (unlikely(error_code & PF_PROT)) {
- /* read, present */
- return 1;
- } else {
- /* read, not present */
- if (unlikely(!(vma->vm_flags & (VM_READ | VM_EXEC | VM_WRITE))))
- return 1;
+ return 0;
}
+ /* read, present: */
+ if (unlikely(error_code & PF_PROT))
+ return 1;
+
+ /* read, not present: */
+ if (unlikely(!(vma->vm_flags & (VM_READ | VM_EXEC | VM_WRITE))))
+ return 1;
+
return 0;
}
+static int fault_in_kernel_space(unsigned long address)
+{
+ return address >= TASK_SIZE_MAX;
+}
+
/*
* This routine handles page faults. It determines the address,
* and the problem, and then passes it off to one of the appropriate
* routines.
*/
-#ifdef CONFIG_X86_64
-asmlinkage
-#endif
-void __kprobes do_page_fault(struct pt_regs *regs, unsigned long error_code)
+dotraplinkage void __kprobes
+do_page_fault(struct pt_regs *regs, unsigned long error_code)
{
- unsigned long address;
+ struct vm_area_struct *vma;
struct task_struct *tsk;
+ unsigned long address;
struct mm_struct *mm;
- struct vm_area_struct *vma;
int write;
int fault;
tsk = current;
mm = tsk->mm;
- prefetchw(&mm->mmap_sem);
- /* get the address */
+ /* Get the faulting address: */
address = read_cr2();
+ /*
+ * Detect and handle instructions that would cause a page fault for
+ * both a tracked kernel page and a userspace page.
+ */
+ if (kmemcheck_active(regs))
+ kmemcheck_hide(regs);
+ prefetchw(&mm->mmap_sem);
+
if (unlikely(kmmio_fault(regs, address)))
return;
* (error_code & 4) == 0, and that the fault was not a
* protection error (error_code & 9) == 0.
*/
-#ifdef CONFIG_X86_32
- if (unlikely(address >= TASK_SIZE)) {
-#else
- if (unlikely(address >= TASK_SIZE64)) {
-#endif
- if (!(error_code & (PF_RSVD|PF_USER|PF_PROT)) &&
- vmalloc_fault(address) >= 0)
- return;
+ if (unlikely(fault_in_kernel_space(address))) {
+ if (!(error_code & (PF_RSVD | PF_USER | PF_PROT))) {
+ if (vmalloc_fault(address) >= 0)
+ return;
+
+ if (kmemcheck_fault(regs, address, error_code))
+ return;
+ }
- /* Can handle a stale RO->RW TLB */
+ /* Can handle a stale RO->RW TLB: */
if (spurious_fault(error_code, address))
return;
- /* kprobes don't want to hook the spurious faults. */
+ /* kprobes don't want to hook the spurious faults: */
if (notify_page_fault(regs))
return;
/*
* Don't take the mm semaphore here. If we fixup a prefetch
- * fault we could otherwise deadlock.
+ * fault we could otherwise deadlock:
*/
bad_area_nosemaphore(regs, error_code, address);
+
return;
}
+ /* kprobes don't want to hook the spurious faults: */
if (unlikely(notify_page_fault(regs)))
return;
/*
* vmalloc fault has been handled.
*
* User-mode registers count as a user access even for any
- * potential system fault or CPU buglet.
+ * potential system fault or CPU buglet:
*/
if (user_mode_vm(regs)) {
local_irq_enable();
error_code |= PF_USER;
- } else if (regs->flags & X86_EFLAGS_IF)
- local_irq_enable();
+ } else {
+ if (regs->flags & X86_EFLAGS_IF)
+ local_irq_enable();
+ }
-#ifdef CONFIG_X86_64
if (unlikely(error_code & PF_RSVD))
pgtable_bad(regs, error_code, address);
-#endif
+
+ perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS, 1, 0, regs, address);
/*
- * 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 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)) {
bad_area_nosemaphore(regs, error_code, address);
/*
* When running in the kernel we expect faults to occur only to
- * addresses in user space. All other faults represent errors in the
- * kernel and should generate an OOPS. Unfortunately, in the case of an
- * erroneous fault occurring in a code path which already holds mmap_sem
- * we will deadlock attempting to validate the fault against the
- * address space. Luckily the kernel only validly references user
- * space from well defined areas of code, which are listed in the
- * exceptions table.
+ * addresses in user space. All other faults represent errors in
+ * the kernel and should generate an OOPS. Unfortunately, in the
+ * case of an erroneous fault occurring in a code path which already
+ * holds mmap_sem we will deadlock attempting to validate the fault
+ * against the address space. Luckily the kernel only validly
+ * references user space from well defined areas of code, which are
+ * listed in the exceptions table.
*
* As the vast majority of faults will be valid we will only perform
- * the source reference check when there is a possibility of a deadlock.
- * Attempt to lock the address space, if we cannot we then validate the
- * source. If this is invalid we can skip the address space check,
- * thus avoiding the deadlock.
+ * the source reference check when there is a possibility of a
+ * deadlock. Attempt to lock the address space, if we cannot we then
+ * validate the source. If this is invalid we can skip the address
+ * space check, thus avoiding the deadlock:
*/
if (unlikely(!down_read_trylock(&mm->mmap_sem))) {
if ((error_code & PF_USER) == 0 &&
return;
}
down_read(&mm->mmap_sem);
+ } else {
+ /*
+ * The above down_read_trylock() might have succeeded in
+ * which case we'll have missed the might_sleep() from
+ * down_read():
+ */
+ might_sleep();
}
vma = find_vma(mm, address);
/*
* Accessing the stack below %sp is always a bug.
* The large cushion allows instructions like enter
- * and pusha to work. ("enter $65535,$31" pushes
+ * and pusha to work. ("enter $65535, $31" pushes
* 32 pointers and then decrements %sp by 65535.)
*/
if (unlikely(address + 65536 + 32 * sizeof(unsigned long) < regs->sp)) {
*/
good_area:
write = error_code & PF_WRITE;
+
if (unlikely(access_error(error_code, write, vma))) {
bad_area_access_error(regs, error_code, address);
return;
/*
* If for any reason at all we couldn't handle the fault,
* make sure we exit gracefully rather than endlessly redo
- * the fault.
+ * the fault:
*/
- fault = handle_mm_fault(mm, vma, address, write);
+ fault = handle_mm_fault(mm, vma, address, write ? FAULT_FLAG_WRITE : 0);
+
if (unlikely(fault & VM_FAULT_ERROR)) {
mm_fault_error(regs, error_code, address, fault);
return;
}
- if (fault & VM_FAULT_MAJOR)
+
+ if (fault & VM_FAULT_MAJOR) {
tsk->maj_flt++;
- else
+ perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS_MAJ, 1, 0,
+ regs, address);
+ } else {
tsk->min_flt++;
-
-#ifdef CONFIG_X86_32
- /*
- * Did it hit the DOS screen memory VA from vm86 mode?
- */
- if (v8086_mode(regs)) {
- unsigned long bit = (address - 0xA0000) >> PAGE_SHIFT;
- if (bit < 32)
- tsk->thread.screen_bitmap |= 1 << bit;
+ perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS_MIN, 1, 0,
+ regs, address);
}
-#endif
- up_read(&mm->mmap_sem);
-}
-
-DEFINE_SPINLOCK(pgd_lock);
-LIST_HEAD(pgd_list);
-
-void vmalloc_sync_all(void)
-{
- unsigned long address;
-
-#ifdef CONFIG_X86_32
- if (SHARED_KERNEL_PMD)
- return;
- for (address = VMALLOC_START & PMD_MASK;
- address >= TASK_SIZE && address < FIXADDR_TOP;
- address += PMD_SIZE) {
- unsigned long flags;
- struct page *page;
-
- spin_lock_irqsave(&pgd_lock, flags);
- list_for_each_entry(page, &pgd_list, lru) {
- if (!vmalloc_sync_one(page_address(page),
- address))
- break;
- }
- spin_unlock_irqrestore(&pgd_lock, flags);
- }
-#else /* CONFIG_X86_64 */
- for (address = VMALLOC_START & PGDIR_MASK; address <= VMALLOC_END;
- address += PGDIR_SIZE) {
- const pgd_t *pgd_ref = pgd_offset_k(address);
- unsigned long flags;
- struct page *page;
+ check_v8086_mode(regs, address, tsk);
- if (pgd_none(*pgd_ref))
- continue;
- spin_lock_irqsave(&pgd_lock, flags);
- list_for_each_entry(page, &pgd_list, lru) {
- pgd_t *pgd;
- pgd = (pgd_t *)page_address(page) + pgd_index(address);
- if (pgd_none(*pgd))
- set_pgd(pgd, *pgd_ref);
- else
- BUG_ON(pgd_page_vaddr(*pgd) != pgd_page_vaddr(*pgd_ref));
- }
- spin_unlock_irqrestore(&pgd_lock, flags);
- }
-#endif
+ up_read(&mm->mmap_sem);
}
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff