From: Joerg Roedel <jroedel@xxxxxxx> Subject: x86/mm/32: implement arch_sync_kernel_mappings() Implement the function to sync changes in vmalloc and ioremap ranges to all page-tables. Link: http://lkml.kernel.org/r/20200515140023.25469-6-joro@xxxxxxxxxx Signed-off-by: Joerg Roedel <jroedel@xxxxxxx> Acked-by: Andy Lutomirski <luto@xxxxxxxxxx> Acked-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx> Cc: Arnd Bergmann <arnd@xxxxxxxx> Cc: Christoph Hellwig <hch@xxxxxx> Cc: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx> Cc: "H . Peter Anvin" <hpa@xxxxxxxxx> Cc: Ingo Molnar <mingo@xxxxxxx> Cc: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx> Cc: Michal Hocko <mhocko@xxxxxxxxxx> Cc: "Rafael J. Wysocki" <rjw@xxxxxxxxxxxxx> Cc: Steven Rostedt (VMware) <rostedt@xxxxxxxxxxx> Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Cc: Vlastimil Babka <vbabka@xxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- arch/x86/include/asm/pgtable-2level_types.h | 2 + arch/x86/include/asm/pgtable-3level_types.h | 2 + arch/x86/mm/fault.c | 25 +++++++++++------- 3 files changed, 20 insertions(+), 9 deletions(-) --- a/arch/x86/include/asm/pgtable-2level_types.h~x86-mm-32-implement-arch_sync_kernel_mappings +++ a/arch/x86/include/asm/pgtable-2level_types.h @@ -20,6 +20,8 @@ typedef union { #define SHARED_KERNEL_PMD 0 +#define ARCH_PAGE_TABLE_SYNC_MASK PGTBL_PMD_MODIFIED + /* * traditional i386 two-level paging structure: */ --- a/arch/x86/include/asm/pgtable-3level_types.h~x86-mm-32-implement-arch_sync_kernel_mappings +++ a/arch/x86/include/asm/pgtable-3level_types.h @@ -27,6 +27,8 @@ typedef union { #define SHARED_KERNEL_PMD (!static_cpu_has(X86_FEATURE_PTI)) #endif +#define ARCH_PAGE_TABLE_SYNC_MASK (SHARED_KERNEL_PMD ? 0 : PGTBL_PMD_MODIFIED) + /* * PGDIR_SHIFT determines what a top-level page table entry can map */ --- a/arch/x86/mm/fault.c~x86-mm-32-implement-arch_sync_kernel_mappings +++ a/arch/x86/mm/fault.c @@ -190,16 +190,13 @@ static inline pmd_t *vmalloc_sync_one(pg return pmd_k; } -static void vmalloc_sync(void) +void arch_sync_kernel_mappings(unsigned long start, unsigned long end) { - unsigned long address; + unsigned long addr; - if (SHARED_KERNEL_PMD) - return; - - for (address = VMALLOC_START & PMD_MASK; - address >= TASK_SIZE_MAX && address < VMALLOC_END; - address += PMD_SIZE) { + for (addr = start & PMD_MASK; + addr >= TASK_SIZE_MAX && addr < VMALLOC_END; + addr += PMD_SIZE) { struct page *page; spin_lock(&pgd_lock); @@ -210,13 +207,23 @@ static void vmalloc_sync(void) pgt_lock = &pgd_page_get_mm(page)->page_table_lock; spin_lock(pgt_lock); - vmalloc_sync_one(page_address(page), address); + vmalloc_sync_one(page_address(page), addr); spin_unlock(pgt_lock); } spin_unlock(&pgd_lock); } } +static void vmalloc_sync(void) +{ + unsigned long address; + + if (SHARED_KERNEL_PMD) + return; + + arch_sync_kernel_mappings(VMALLOC_START, VMALLOC_END); +} + void vmalloc_sync_mappings(void) { vmalloc_sync(); _
