From 426e34cc4f6094cefe4f3175764cdf583128e7cd Mon Sep 17 00:00:00 2001 From: Matt Fleming Date: Fri, 6 Dec 2013 21:13:04 +0000 Subject: [PATCH] x86/mm/pageattr: Always dump the right page table in an oops Now that we have EFI-specific page tables we need to lookup the pgd when dumping those page tables, rather than assuming that swapper_pgdir is the current pgdir. Remove the double underscore prefix, which is usually reserved for static functions. Acked-by: Borislav Petkov Signed-off-by: Matt Fleming --- arch/x86/include/asm/pgtable_types.h | 2 ++ arch/x86/mm/fault.c | 7 ++++++- arch/x86/mm/pageattr.c | 12 ++++++++---- 3 files changed, 16 insertions(+), 5 deletions(-) diff --git a/arch/x86/include/asm/pgtable_types.h b/arch/x86/include/asm/pgtable_types.h index 1aa9ccd43223..24ae4211ba34 100644 --- a/arch/x86/include/asm/pgtable_types.h +++ b/arch/x86/include/asm/pgtable_types.h @@ -382,6 +382,8 @@ static inline void update_page_count(int level, unsigned long pages) { } * as a pte too. */ extern pte_t *lookup_address(unsigned long address, unsigned int *level); +extern pte_t *lookup_address_in_pgd(pgd_t *pgd, unsigned long address, + unsigned int *level); extern phys_addr_t slow_virt_to_phys(void *__address); extern int kernel_map_pages_in_pgd(pgd_t *pgd, u64 pfn, unsigned long address, unsigned numpages, unsigned long page_flags); diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c index 6dea040cc3a1..6055a2001b27 100644 --- a/arch/x86/mm/fault.c +++ b/arch/x86/mm/fault.c @@ -584,8 +584,13 @@ show_fault_oops(struct pt_regs *regs, unsigned long error_code, if (error_code & PF_INSTR) { unsigned int level; + pgd_t *pgd; + pte_t *pte; - pte_t *pte = lookup_address(address, &level); + pgd = __va(read_cr3() & PHYSICAL_PAGE_MASK); + pgd += pgd_index(address); + + pte = lookup_address_in_pgd(pgd, address, &level); if (pte && pte_present(*pte) && !pte_exec(*pte)) printk(nx_warning, from_kuid(&init_user_ns, current_uid())); diff --git a/arch/x86/mm/pageattr.c b/arch/x86/mm/pageattr.c index b3b19f46c016..14c656f0483b 100644 --- a/arch/x86/mm/pageattr.c +++ b/arch/x86/mm/pageattr.c @@ -323,8 +323,12 @@ static inline pgprot_t static_protections(pgprot_t prot, unsigned long address, return prot; } -static pte_t *__lookup_address_in_pgd(pgd_t *pgd, unsigned long address, - unsigned int *level) +/* + * Lookup the page table entry for a virtual address in a specific pgd. + * Return a pointer to the entry and the level of the mapping. + */ +pte_t *lookup_address_in_pgd(pgd_t *pgd, unsigned long address, + unsigned int *level) { pud_t *pud; pmd_t *pmd; @@ -365,7 +369,7 @@ static pte_t *__lookup_address_in_pgd(pgd_t *pgd, unsigned long address, */ pte_t *lookup_address(unsigned long address, unsigned int *level) { - return __lookup_address_in_pgd(pgd_offset_k(address), address, level); + return lookup_address_in_pgd(pgd_offset_k(address), address, level); } EXPORT_SYMBOL_GPL(lookup_address); @@ -373,7 +377,7 @@ static pte_t *_lookup_address_cpa(struct cpa_data *cpa, unsigned long address, unsigned int *level) { if (cpa->pgd) - return __lookup_address_in_pgd(cpa->pgd + pgd_index(address), + return lookup_address_in_pgd(cpa->pgd + pgd_index(address), address, level); return lookup_address(address, level); -- 2.34.1