diff options
Diffstat (limited to 'arch/powerpc/mm/pgtable-book3s64.c')
| -rw-r--r-- | arch/powerpc/mm/pgtable-book3s64.c | 24 |
1 files changed, 23 insertions, 1 deletions
diff --git a/arch/powerpc/mm/pgtable-book3s64.c b/arch/powerpc/mm/pgtable-book3s64.c index 31eed8fa8e99..3b65917785a5 100644 --- a/arch/powerpc/mm/pgtable-book3s64.c +++ b/arch/powerpc/mm/pgtable-book3s64.c @@ -9,6 +9,7 @@ #include <linux/sched.h> #include <linux/mm_types.h> +#include <misc/cxl-base.h> #include <asm/pgalloc.h> #include <asm/tlb.h> @@ -64,6 +65,27 @@ void set_pmd_at(struct mm_struct *mm, unsigned long addr, trace_hugepage_set_pmd(addr, pmd_val(pmd)); return set_pte_at(mm, addr, pmdp_ptep(pmdp), pmd_pte(pmd)); } + +static void do_nothing(void *unused) +{ + +} +/* + * Serialize against find_current_mm_pte which does lock-less + * lookup in page tables with local interrupts disabled. For huge pages + * it casts pmd_t to pte_t. Since format of pte_t is different from + * pmd_t we want to prevent transit from pmd pointing to page table + * to pmd pointing to huge page (and back) while interrupts are disabled. + * We clear pmd to possibly replace it with page table pointer in + * different code paths. So make sure we wait for the parallel + * find_current_mm_pte to finish. + */ +void serialize_against_pte_lookup(struct mm_struct *mm) +{ + smp_mb(); + smp_call_function_many(mm_cpumask(mm), do_nothing, NULL, 1); +} + /* * We use this to invalidate a pmdp entry before switching from a * hugepte to regular pmd entry. @@ -77,7 +99,7 @@ void pmdp_invalidate(struct vm_area_struct *vma, unsigned long address, * This ensures that generic code that rely on IRQ disabling * to prevent a parallel THP split work as expected. */ - kick_all_cpus_sync(); + serialize_against_pte_lookup(vma->vm_mm); } static pmd_t pmd_set_protbits(pmd_t pmd, pgprot_t pgprot) |