#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:
tsk->thread.screen_bitmap |= 1 << bit;
}
-static void dump_pagetable(unsigned long address)
+static bool low_pfn(unsigned long pfn)
{
- __typeof__(pte_val(__pte(0))) page;
+ return pfn < max_low_pfn;
+}
- page = read_cr3();
- page = ((__typeof__(page) *) __va(page))[address >> PGDIR_SHIFT];
+static void dump_pagetable(unsigned long address)
+{
+ pgd_t *base = __va(read_cr3());
+ pgd_t *pgd = &base[pgd_index(address)];
+ pmd_t *pmd;
+ pte_t *pte;
#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
* And let's rather not kmap-atomic the pte, just in case
* 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");
}
}
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";
+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 void dump_pagetable(unsigned long address)
{
- pgd_t *pgd;
+ 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;
- pgd = (pgd_t *)read_cr3();
-
- pgd = __va((unsigned long)pgd & PHYSICAL_PAGE_MASK);
-
- pgd += pgd_index(address);
if (bad_address(pgd))
goto bad;
if (!printk_ratelimit())
return;
- printk(KERN_CONT "%s%s[%d]: segfault at %lx ip %p sp %p error %lx",
+ 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);
tsk = current;
mm = tsk->mm;
- prefetchw(&mm->mmap_sem);
-
/* 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;
* protection error (error_code & 9) == 0.
*/
if (unlikely(fault_in_kernel_space(address))) {
- if (!(error_code & (PF_RSVD|PF_USER|PF_PROT)) &&
- vmalloc_fault(address) >= 0)
- return;
+ 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: */
if (spurious_fault(error_code, address))
if (unlikely(error_code & PF_RSVD))
pgtable_bad(regs, error_code, address);
+ 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:
* make sure we exit gracefully rather than endlessly redo
* 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++;
+ perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS_MIN, 1, 0,
+ regs, address);
+ }
check_v8086_mode(regs, address, tsk);
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff