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| author | Sasha Levin <sasha.levin@oracle.com> | 2014-01-23 15:52:54 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2014-01-23 16:36:50 -0800 |
| commit | 309381feaee564281c3d9e90fbca8963bb7428ad (patch) | |
| tree | 7e9f990c0cffcb8c5fc90deb1c7eac445c5ada0e /arch/x86/mm/gup.c | |
| parent | e3bba3c3c90cd434c1ccb9e5dc704a96baf9541c (diff) | |
| download | linux-309381feaee564281c3d9e90fbca8963bb7428ad.tar.gz | |
mm: dump page when hitting a VM_BUG_ON using VM_BUG_ON_PAGE
Most of the VM_BUG_ON assertions are performed on a page. Usually, when one of these assertions fails we'll get a BUG_ON with a call stack and the registers. I've recently noticed based on the requests to add a small piece of code that dumps the page to various VM_BUG_ON sites that the page dump is quite useful to people debugging issues in mm. This patch adds a VM_BUG_ON_PAGE(cond, page) which beyond doing what VM_BUG_ON() does, also dumps the page before executing the actual BUG_ON. [akpm@linux-foundation.org: fix up includes] Signed-off-by: Sasha Levin <sasha.levin@oracle.com> Cc: "Kirill A. Shutemov" <kirill@shutemov.name> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'arch/x86/mm/gup.c')
| -rw-r--r-- | arch/x86/mm/gup.c | 8 |
1 files changed, 4 insertions, 4 deletions
diff --git a/arch/x86/mm/gup.c b/arch/x86/mm/gup.c index 0596e8e0cc19..207d9aef662d 100644 --- a/arch/x86/mm/gup.c +++ b/arch/x86/mm/gup.c @@ -108,8 +108,8 @@ static noinline int gup_pte_range(pmd_t pmd, unsigned long addr, static inline void get_head_page_multiple(struct page *page, int nr) { - VM_BUG_ON(page != compound_head(page)); - VM_BUG_ON(page_count(page) == 0); + VM_BUG_ON_PAGE(page != compound_head(page), page); + VM_BUG_ON_PAGE(page_count(page) == 0, page); atomic_add(nr, &page->_count); SetPageReferenced(page); } @@ -135,7 +135,7 @@ static noinline int gup_huge_pmd(pmd_t pmd, unsigned long addr, head = pte_page(pte); page = head + ((addr & ~PMD_MASK) >> PAGE_SHIFT); do { - VM_BUG_ON(compound_head(page) != head); + VM_BUG_ON_PAGE(compound_head(page) != head, page); pages[*nr] = page; if (PageTail(page)) get_huge_page_tail(page); @@ -212,7 +212,7 @@ static noinline int gup_huge_pud(pud_t pud, unsigned long addr, head = pte_page(pte); page = head + ((addr & ~PUD_MASK) >> PAGE_SHIFT); do { - VM_BUG_ON(compound_head(page) != head); + VM_BUG_ON_PAGE(compound_head(page) != head, page); pages[*nr] = page; if (PageTail(page)) get_huge_page_tail(page); |