diff options
Diffstat (limited to 'arch/x86/mm')
| -rw-r--r-- | arch/x86/mm/init.c | 9 | ||||
| -rw-r--r-- | arch/x86/mm/init_64.c | 15 | ||||
| -rw-r--r-- | arch/x86/mm/kaslr.c | 10 | ||||
| -rw-r--r-- | arch/x86/mm/pgtable.c | 31 | ||||
| -rw-r--r-- | arch/x86/mm/tlb.c | 29 |
5 files changed, 57 insertions, 37 deletions
diff --git a/arch/x86/mm/init.c b/arch/x86/mm/init.c index 62aa4d66a032..bfa444a7dbb0 100644 --- a/arch/x86/mm/init.c +++ b/arch/x86/mm/init.c @@ -645,8 +645,13 @@ static void __init memory_map_top_down(unsigned long map_start, */ addr = memblock_phys_alloc_range(PMD_SIZE, PMD_SIZE, map_start, map_end); - memblock_phys_free(addr, PMD_SIZE); - real_end = addr + PMD_SIZE; + if (!addr) { + pr_warn("Failed to release memory for alloc_low_pages()"); + real_end = max(map_start, ALIGN_DOWN(map_end, PMD_SIZE)); + } else { + memblock_phys_free(addr, PMD_SIZE); + real_end = addr + PMD_SIZE; + } /* step_size need to be small so pgt_buf from BRK could cover it */ step_size = PMD_SIZE; diff --git a/arch/x86/mm/init_64.c b/arch/x86/mm/init_64.c index 01ea7c6df303..17c89dad4f7f 100644 --- a/arch/x86/mm/init_64.c +++ b/arch/x86/mm/init_64.c @@ -967,9 +967,18 @@ int add_pages(int nid, unsigned long start_pfn, unsigned long nr_pages, ret = __add_pages(nid, start_pfn, nr_pages, params); WARN_ON_ONCE(ret); - /* update max_pfn, max_low_pfn and high_memory */ - update_end_of_memory_vars(start_pfn << PAGE_SHIFT, - nr_pages << PAGE_SHIFT); + /* + * Special case: add_pages() is called by memremap_pages() for adding device + * private pages. Do not bump up max_pfn in the device private path, + * because max_pfn changes affect dma_addressing_limited(). + * + * dma_addressing_limited() returning true when max_pfn is the device's + * addressable memory can force device drivers to use bounce buffers + * and impact their performance negatively: + */ + if (!params->pgmap) + /* update max_pfn, max_low_pfn and high_memory */ + update_end_of_memory_vars(start_pfn << PAGE_SHIFT, nr_pages << PAGE_SHIFT); return ret; } diff --git a/arch/x86/mm/kaslr.c b/arch/x86/mm/kaslr.c index 11a93542d198..3c306de52fd4 100644 --- a/arch/x86/mm/kaslr.c +++ b/arch/x86/mm/kaslr.c @@ -113,8 +113,14 @@ void __init kernel_randomize_memory(void) memory_tb = DIV_ROUND_UP(max_pfn << PAGE_SHIFT, 1UL << TB_SHIFT) + CONFIG_RANDOMIZE_MEMORY_PHYSICAL_PADDING; - /* Adapt physical memory region size based on available memory */ - if (memory_tb < kaslr_regions[0].size_tb) + /* + * Adapt physical memory region size based on available memory, + * except when CONFIG_PCI_P2PDMA is enabled. P2PDMA exposes the + * device BAR space assuming the direct map space is large enough + * for creating a ZONE_DEVICE mapping in the direct map corresponding + * to the physical BAR address. + */ + if (!IS_ENABLED(CONFIG_PCI_P2PDMA) && (memory_tb < kaslr_regions[0].size_tb)) kaslr_regions[0].size_tb = memory_tb; /* diff --git a/arch/x86/mm/pgtable.c b/arch/x86/mm/pgtable.c index 1fef5ad32d5a..1ddbd799acdf 100644 --- a/arch/x86/mm/pgtable.c +++ b/arch/x86/mm/pgtable.c @@ -18,25 +18,6 @@ EXPORT_SYMBOL(physical_mask); #define PGTABLE_HIGHMEM 0 #endif -#ifndef CONFIG_PARAVIRT -#ifndef CONFIG_PT_RECLAIM -static inline -void paravirt_tlb_remove_table(struct mmu_gather *tlb, void *table) -{ - struct ptdesc *ptdesc = (struct ptdesc *)table; - - pagetable_dtor(ptdesc); - tlb_remove_page(tlb, ptdesc_page(ptdesc)); -} -#else -static inline -void paravirt_tlb_remove_table(struct mmu_gather *tlb, void *table) -{ - tlb_remove_table(tlb, table); -} -#endif /* !CONFIG_PT_RECLAIM */ -#endif /* !CONFIG_PARAVIRT */ - gfp_t __userpte_alloc_gfp = GFP_PGTABLE_USER | PGTABLE_HIGHMEM; pgtable_t pte_alloc_one(struct mm_struct *mm) @@ -64,7 +45,7 @@ early_param("userpte", setup_userpte); void ___pte_free_tlb(struct mmu_gather *tlb, struct page *pte) { paravirt_release_pte(page_to_pfn(pte)); - paravirt_tlb_remove_table(tlb, page_ptdesc(pte)); + tlb_remove_table(tlb, page_ptdesc(pte)); } #if CONFIG_PGTABLE_LEVELS > 2 @@ -78,21 +59,21 @@ void ___pmd_free_tlb(struct mmu_gather *tlb, pmd_t *pmd) #ifdef CONFIG_X86_PAE tlb->need_flush_all = 1; #endif - paravirt_tlb_remove_table(tlb, virt_to_ptdesc(pmd)); + tlb_remove_table(tlb, virt_to_ptdesc(pmd)); } #if CONFIG_PGTABLE_LEVELS > 3 void ___pud_free_tlb(struct mmu_gather *tlb, pud_t *pud) { paravirt_release_pud(__pa(pud) >> PAGE_SHIFT); - paravirt_tlb_remove_table(tlb, virt_to_ptdesc(pud)); + tlb_remove_table(tlb, virt_to_ptdesc(pud)); } #if CONFIG_PGTABLE_LEVELS > 4 void ___p4d_free_tlb(struct mmu_gather *tlb, p4d_t *p4d) { paravirt_release_p4d(__pa(p4d) >> PAGE_SHIFT); - paravirt_tlb_remove_table(tlb, virt_to_ptdesc(p4d)); + tlb_remove_table(tlb, virt_to_ptdesc(p4d)); } #endif /* CONFIG_PGTABLE_LEVELS > 4 */ #endif /* CONFIG_PGTABLE_LEVELS > 3 */ @@ -404,7 +385,7 @@ static inline pgd_t *_pgd_alloc(struct mm_struct *mm) * We allocate one page for pgd. */ if (!SHARED_KERNEL_PMD) - return __pgd_alloc(mm, PGD_ALLOCATION_ORDER); + return __pgd_alloc(mm, pgd_allocation_order()); /* * Now PAE kernel is not running as a Xen domain. We can allocate @@ -424,7 +405,7 @@ static inline void _pgd_free(struct mm_struct *mm, pgd_t *pgd) static inline pgd_t *_pgd_alloc(struct mm_struct *mm) { - return __pgd_alloc(mm, PGD_ALLOCATION_ORDER); + return __pgd_alloc(mm, pgd_allocation_order()); } static inline void _pgd_free(struct mm_struct *mm, pgd_t *pgd) diff --git a/arch/x86/mm/tlb.c b/arch/x86/mm/tlb.c index 6cf881a942bb..3c81edd54c5c 100644 --- a/arch/x86/mm/tlb.c +++ b/arch/x86/mm/tlb.c @@ -389,9 +389,9 @@ static void cond_mitigation(struct task_struct *next) prev_mm = this_cpu_read(cpu_tlbstate.last_user_mm_spec); /* - * Avoid user/user BTB poisoning by flushing the branch predictor - * when switching between processes. This stops one process from - * doing Spectre-v2 attacks on another. + * Avoid user->user BTB/RSB poisoning by flushing them when switching + * between processes. This stops one process from doing Spectre-v2 + * attacks on another. * * Both, the conditional and the always IBPB mode use the mm * pointer to avoid the IBPB when switching between tasks of the @@ -621,7 +621,11 @@ void switch_mm_irqs_off(struct mm_struct *unused, struct mm_struct *next, choose_new_asid(next, next_tlb_gen, &new_asid, &need_flush); - /* Let nmi_uaccess_okay() know that we're changing CR3. */ + /* + * Indicate that CR3 is about to change. nmi_uaccess_okay() + * and others are sensitive to the window where mm_cpumask(), + * CR3 and cpu_tlbstate.loaded_mm are not all in sync. + */ this_cpu_write(cpu_tlbstate.loaded_mm, LOADED_MM_SWITCHING); barrier(); } @@ -895,8 +899,16 @@ done: static bool should_flush_tlb(int cpu, void *data) { + struct mm_struct *loaded_mm = per_cpu(cpu_tlbstate.loaded_mm, cpu); struct flush_tlb_info *info = data; + /* + * Order the 'loaded_mm' and 'is_lazy' against their + * write ordering in switch_mm_irqs_off(). Ensure + * 'is_lazy' is at least as new as 'loaded_mm'. + */ + smp_rmb(); + /* Lazy TLB will get flushed at the next context switch. */ if (per_cpu(cpu_tlbstate_shared.is_lazy, cpu)) return false; @@ -905,8 +917,15 @@ static bool should_flush_tlb(int cpu, void *data) if (!info->mm) return true; + /* + * While switching, the remote CPU could have state from + * either the prev or next mm. Assume the worst and flush. + */ + if (loaded_mm == LOADED_MM_SWITCHING) + return true; + /* The target mm is loaded, and the CPU is not lazy. */ - if (per_cpu(cpu_tlbstate.loaded_mm, cpu) == info->mm) + if (loaded_mm == info->mm) return true; /* In cpumask, but not the loaded mm? Periodically remove by flushing. */ |