diff options
Diffstat (limited to 'arch/x86/mm/fault.c')
-rw-r--r-- | arch/x86/mm/fault.c | 75 |
1 files changed, 28 insertions, 47 deletions
diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c index 2a1fa10c6a98..b836a7274e12 100644 --- a/arch/x86/mm/fault.c +++ b/arch/x86/mm/fault.c @@ -396,14 +396,18 @@ static void dump_pagetable(unsigned long address) pte_t *pte; #ifdef CONFIG_X86_PAE - printk("*pdpt = %016Lx ", pgd_val(*pgd)); + pr_info("*pdpt = %016Lx ", pgd_val(*pgd)); if (!low_pfn(pgd_val(*pgd) >> PAGE_SHIFT) || !pgd_present(*pgd)) goto out; +#define pr_pde pr_cont +#else +#define pr_pde pr_info #endif p4d = p4d_offset(pgd, address); pud = pud_offset(p4d, address); pmd = pmd_offset(pud, address); - printk(KERN_CONT "*pde = %0*Lx ", sizeof(*pmd) * 2, (u64)pmd_val(*pmd)); + pr_pde("*pde = %0*Lx ", sizeof(*pmd) * 2, (u64)pmd_val(*pmd)); +#undef pr_pde /* * We must not directly access the pte in the highpte @@ -415,9 +419,9 @@ static void dump_pagetable(unsigned long address) goto out; pte = pte_offset_kernel(pmd, address); - printk("*pte = %0*Lx ", sizeof(*pte) * 2, (u64)pte_val(*pte)); + pr_cont("*pte = %0*Lx ", sizeof(*pte) * 2, (u64)pte_val(*pte)); out: - printk("\n"); + pr_cont("\n"); } #else /* CONFIG_X86_64: */ @@ -565,7 +569,7 @@ static void dump_pagetable(unsigned long address) if (bad_address(pgd)) goto bad; - printk("PGD %lx ", pgd_val(*pgd)); + pr_info("PGD %lx ", pgd_val(*pgd)); if (!pgd_present(*pgd)) goto out; @@ -574,7 +578,7 @@ static void dump_pagetable(unsigned long address) if (bad_address(p4d)) goto bad; - printk("P4D %lx ", p4d_val(*p4d)); + pr_cont("P4D %lx ", p4d_val(*p4d)); if (!p4d_present(*p4d) || p4d_large(*p4d)) goto out; @@ -582,7 +586,7 @@ static void dump_pagetable(unsigned long address) if (bad_address(pud)) goto bad; - printk("PUD %lx ", pud_val(*pud)); + pr_cont("PUD %lx ", pud_val(*pud)); if (!pud_present(*pud) || pud_large(*pud)) goto out; @@ -590,7 +594,7 @@ static void dump_pagetable(unsigned long address) if (bad_address(pmd)) goto bad; - printk("PMD %lx ", pmd_val(*pmd)); + pr_cont("PMD %lx ", pmd_val(*pmd)); if (!pmd_present(*pmd) || pmd_large(*pmd)) goto out; @@ -598,12 +602,12 @@ static void dump_pagetable(unsigned long address) if (bad_address(pte)) goto bad; - printk("PTE %lx", pte_val(*pte)); + pr_cont("PTE %lx", pte_val(*pte)); out: - printk("\n"); + pr_cont("\n"); return; bad: - printk("BAD\n"); + pr_info("BAD\n"); } #endif /* CONFIG_X86_64 */ @@ -1254,10 +1258,6 @@ static inline bool smap_violation(int error_code, struct pt_regs *regs) * This routine handles page faults. It determines the address, * and the problem, and then passes it off to one of the appropriate * routines. - * - * This function must have noinline because both callers - * {,trace_}do_page_fault() have notrace on. Having this an actual function - * guarantees there's a function trace entry. */ static noinline void __do_page_fault(struct pt_regs *regs, unsigned long error_code, @@ -1490,27 +1490,6 @@ good_area: } NOKPROBE_SYMBOL(__do_page_fault); -dotraplinkage void notrace -do_page_fault(struct pt_regs *regs, unsigned long error_code) -{ - unsigned long address = read_cr2(); /* Get the faulting address */ - enum ctx_state prev_state; - - /* - * We must have this function tagged with __kprobes, notrace and call - * read_cr2() before calling anything else. To avoid calling any kind - * of tracing machinery before we've observed the CR2 value. - * - * exception_{enter,exit}() contain all sorts of tracepoints. - */ - - prev_state = exception_enter(); - __do_page_fault(regs, error_code, address); - exception_exit(prev_state); -} -NOKPROBE_SYMBOL(do_page_fault); - -#ifdef CONFIG_TRACING static nokprobe_inline void trace_page_fault_entries(unsigned long address, struct pt_regs *regs, unsigned long error_code) @@ -1521,22 +1500,24 @@ trace_page_fault_entries(unsigned long address, struct pt_regs *regs, trace_page_fault_kernel(address, regs, error_code); } +/* + * We must have this function blacklisted from kprobes, tagged with notrace + * and call read_cr2() before calling anything else. To avoid calling any + * kind of tracing machinery before we've observed the CR2 value. + * + * exception_{enter,exit}() contains all sorts of tracepoints. + */ dotraplinkage void notrace -trace_do_page_fault(struct pt_regs *regs, unsigned long error_code) +do_page_fault(struct pt_regs *regs, unsigned long error_code) { - /* - * The exception_enter and tracepoint processing could - * trigger another page faults (user space callchain - * reading) and destroy the original cr2 value, so read - * the faulting address now. - */ - unsigned long address = read_cr2(); + unsigned long address = read_cr2(); /* Get the faulting address */ enum ctx_state prev_state; prev_state = exception_enter(); - trace_page_fault_entries(address, regs, error_code); + if (trace_pagefault_enabled()) + trace_page_fault_entries(address, regs, error_code); + __do_page_fault(regs, error_code, address); exception_exit(prev_state); } -NOKPROBE_SYMBOL(trace_do_page_fault); -#endif /* CONFIG_TRACING */ +NOKPROBE_SYMBOL(do_page_fault); |