diff options
| -rw-r--r-- | arch/x86/include/asm/io.h | 1 | ||||
| -rw-r--r-- | arch/x86/mm/ioremap.c | 5 | ||||
| -rw-r--r-- | arch/x86/xen/mmu.c | 26 |
3 files changed, 24 insertions, 8 deletions
diff --git a/arch/x86/include/asm/io.h b/arch/x86/include/asm/io.h index 30a3e97..66aee6c 100644 --- a/arch/x86/include/asm/io.h +++ b/arch/x86/include/asm/io.h @@ -348,6 +348,7 @@ extern void __iomem *early_memremap(resource_size_t phys_addr, unsigned long size); extern void early_iounmap(void __iomem *addr, unsigned long size); extern void fixup_early_ioremap(void); +extern bool is_early_ioremap_ptep(pte_t *ptep); #define IO_SPACE_LIMIT 0xffff diff --git a/arch/x86/mm/ioremap.c b/arch/x86/mm/ioremap.c index 3ba6e06..0369843 100644 --- a/arch/x86/mm/ioremap.c +++ b/arch/x86/mm/ioremap.c @@ -362,6 +362,11 @@ static inline pte_t * __init early_ioremap_pte(unsigned long addr) return &bm_pte[pte_index(addr)]; } +bool __init is_early_ioremap_ptep(pte_t *ptep) +{ + return ptep >= &bm_pte[0] && ptep < &bm_pte[PAGE_SIZE/sizeof(pte_t)]; +} + static unsigned long slot_virt[FIX_BTMAPS_SLOTS] __initdata; void __init early_ioremap_init(void) diff --git a/arch/x86/xen/mmu.c b/arch/x86/xen/mmu.c index 4fe04ac..7d55e9e 100644 --- a/arch/x86/xen/mmu.c +++ b/arch/x86/xen/mmu.c @@ -56,6 +56,7 @@ #include <asm/e820.h> #include <asm/linkage.h> #include <asm/page.h> +#include <asm/init.h> #include <asm/xen/hypercall.h> #include <asm/xen/hypervisor.h> @@ -360,7 +361,8 @@ void make_lowmem_page_readonly(void *vaddr) unsigned int level; pte = lookup_address(address, &level); - BUG_ON(pte == NULL); + if (pte == NULL) + return; /* vaddr missing */ ptev = pte_wrprotect(*pte); @@ -375,7 +377,8 @@ void make_lowmem_page_readwrite(void *vaddr) unsigned int level; pte = lookup_address(address, &level); - BUG_ON(pte == NULL); + if (pte == NULL) + return; /* vaddr missing */ ptev = pte_mkwrite(*pte); @@ -1509,13 +1512,25 @@ static void xen_pgd_free(struct mm_struct *mm, pgd_t *pgd) #endif } -#ifdef CONFIG_X86_32 static __init pte_t mask_rw_pte(pte_t *ptep, pte_t pte) { + unsigned long pfn = pte_pfn(pte); + +#ifdef CONFIG_X86_32 /* If there's an existing pte, then don't allow _PAGE_RW to be set */ if (pte_val_ma(*ptep) & _PAGE_PRESENT) pte = __pte_ma(((pte_val_ma(*ptep) & _PAGE_RW) | ~_PAGE_RW) & pte_val_ma(pte)); +#endif + + /* + * If the new pfn is within the range of the newly allocated + * kernel pagetable, and it isn't being mapped into an + * early_ioremap fixmap slot, make sure it is RO. + */ + if (!is_early_ioremap_ptep(ptep) && + pfn >= e820_table_start && pfn < e820_table_end) + pte = pte_wrprotect(pte); return pte; } @@ -1528,7 +1543,6 @@ static __init void xen_set_pte_init(pte_t *ptep, pte_t pte) xen_set_pte(ptep, pte); } -#endif static void pin_pagetable_pfn(unsigned cmd, unsigned long pfn) { @@ -1973,11 +1987,7 @@ static const struct pv_mmu_ops xen_mmu_ops __initdata = { .alloc_pmd_clone = paravirt_nop, .release_pmd = xen_release_pmd_init, -#ifdef CONFIG_X86_64 - .set_pte = xen_set_pte, -#else .set_pte = xen_set_pte_init, -#endif .set_pte_at = xen_set_pte_at, .set_pmd = xen_set_pmd_hyper, |