From: David Gibson Date: Wed, 22 Mar 2006 08:08:58 +0000 (-0800) Subject: [PATCH] hugepage: Fix hugepage logic in free_pgtables() harder X-Git-Tag: v2.6.17-rc1~1129^2~30 X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=4866920b93fd7d5b520278c3c76e6f4d5a352d81;p=linux-2.6 [PATCH] hugepage: Fix hugepage logic in free_pgtables() harder Turns out the hugepage logic in free_pgtables() was doubly broken. The loop coalescing multiple normal page VMAs into one call to free_pgd_range() had an off by one error, which could mean it would coalesce one hugepage VMA into the same bundle (checking 'vma' not 'next' in the loop). I transferred this bug into the new is_vm_hugetlb_page() based version. Here's the fix. This one didn't bite on powerpc previously for the same reason the is_hugepage_only_range() problem didn't: powerpc's hugetlb_free_pgd_range() is identical to free_pgd_range(). It didn't bite on ia64 because the hugepage region is distant enough from any other region that the separated PMD_SIZE distance test would always prevent coalescing the two together. No libhugetlbfs testsuite regressions (ppc64, POWER5). Signed-off-by: David Gibson Cc: William Lee Irwin III Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- diff --git a/mm/memory.c b/mm/memory.c index f6e3be9cbf..80c3fb370f 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -285,7 +285,7 @@ void free_pgtables(struct mmu_gather **tlb, struct vm_area_struct *vma, * Optimization: gather nearby vmas into one call down */ while (next && next->vm_start <= vma->vm_end + PMD_SIZE - && !is_vm_hugetlb_page(vma)) { + && !is_vm_hugetlb_page(next)) { vma = next; next = vma->vm_next; anon_vma_unlink(vma);