From e0897d75f0b22e8c3a7287a48548c5686ef73447 Mon Sep 17 00:00:00 2001 From: David Rientjes Date: Wed, 20 Jun 2012 12:53:00 -0700 Subject: mm, thp: print useful information when mmap_sem is unlocked in zap_pmd_range Andrea asked for addr, end, vma->vm_start, and vma->vm_end to be emitted when !rwsem_is_locked(&tlb->mm->mmap_sem). Otherwise, debugging the underlying issue is more difficult. Suggested-by: Andrea Arcangeli Signed-off-by: David Rientjes Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/memory.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) (limited to 'mm/memory.c') diff --git a/mm/memory.c b/mm/memory.c index 1b7dc662bf9f..8762c4f915fc 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -1225,7 +1225,15 @@ static inline unsigned long zap_pmd_range(struct mmu_gather *tlb, next = pmd_addr_end(addr, end); if (pmd_trans_huge(*pmd)) { if (next - addr != HPAGE_PMD_SIZE) { - VM_BUG_ON(!rwsem_is_locked(&tlb->mm->mmap_sem)); +#ifdef CONFIG_DEBUG_VM + if (!rwsem_is_locked(&tlb->mm->mmap_sem)) { + pr_err("%s: mmap_sem is unlocked! addr=0x%lx end=0x%lx vma->vm_start=0x%lx vma->vm_end=0x%lx\n", + __func__, addr, end, + vma->vm_start, + vma->vm_end); + BUG(); + } +#endif split_huge_page_pmd(vma->vm_mm, pmd); } else if (zap_huge_pmd(tlb, vma, pmd, addr)) goto next; -- cgit From eb4546bbbdb160aff084d50511165f385756af18 Mon Sep 17 00:00:00 2001 From: Randy Dunlap Date: Wed, 20 Jun 2012 12:53:02 -0700 Subject: mm/memory.c: fix kernel-doc warnings Fix kernel-doc warnings in mm/memory.c: Warning(mm/memory.c:1377): No description found for parameter 'start' Warning(mm/memory.c:1377): Excess function parameter 'address' description in 'zap_page_range' Signed-off-by: Randy Dunlap Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/memory.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'mm/memory.c') diff --git a/mm/memory.c b/mm/memory.c index 8762c4f915fc..2466d1250231 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -1374,7 +1374,7 @@ void unmap_vmas(struct mmu_gather *tlb, /** * zap_page_range - remove user pages in a given range * @vma: vm_area_struct holding the applicable pages - * @address: starting address of pages to zap + * @start: starting address of pages to zap * @size: number of bytes to zap * @details: details of nonlinear truncation or shared cache invalidation * -- cgit