Copying of the pgd range must happen under the pgd_lock. This got broken by the paravirt changes in the -mm tree. Badness can result if you copy the pgd before being added to the list when splitting or rejoining large pages. From: Zachary Amsden <zach@xxxxxxxxxx> Signed-off-by: Zachary Amsden <zach@xxxxxxxxxx> Acked-by: William Lee Irwin III <wli@xxxxxxxxxxxxxx> --- arch/i386/mm/pgtable.c | 8 +++----- 1 file changed, 3 insertions(+), 5 deletions(-) =================================================================== --- a/arch/i386/mm/pgtable.c +++ b/arch/i386/mm/pgtable.c @@ -241,18 +241,16 @@ void pgd_ctor(void *pgd, struct kmem_cac /* !PAE, no pagetable sharing */ memset(pgd, 0, USER_PTRS_PER_PGD*sizeof(pgd_t)); + spin_lock_irqsave(&pgd_lock, flags); + + /* must happen under lock */ clone_pgd_range((pgd_t *)pgd + USER_PTRS_PER_PGD, swapper_pg_dir + USER_PTRS_PER_PGD, KERNEL_PGD_PTRS); - - spin_lock_irqsave(&pgd_lock, flags); - - /* must happen under lock */ paravirt_alloc_pd_clone(__pa(pgd) >> PAGE_SHIFT, __pa(swapper_pg_dir) >> PAGE_SHIFT, USER_PTRS_PER_PGD, KERNEL_PGD_PTRS); - pgd_list_add(pgd); spin_unlock_irqrestore(&pgd_lock, flags); } -- _______________________________________________ Virtualization mailing list Virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/virtualization
