Commit 2a46eed5 authored Nov 20, 2013 by Al Viro Committed by Linus Torvalds Nov 20, 2013

Wrong page freed on preallocate_pmds() failure exit



Note that pmds[i] is simply uninitialized at that point...

Granted, it's very hard to hit (you need split page locks *and*
kmalloc(sizeof(spinlock_t), GFP_KERNEL) failing), but the code is
obviously bogus.

Introduced by commit 09ef4939 ("x86: add missed
pgtable_pmd_page_ctor/dtor calls for preallocated pmds")

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

parent 82023bb7

arch/x86/mm/pgtable.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -209,7 +209,7 @@ static int preallocate_pmds(pmd_t *pmds[])
		if (!pmd)
		failed = true;
		if (pmd && !pgtable_pmd_page_ctor(virt_to_page(pmd))) {
		free_page((unsigned long)pmds[i]);
		free_page((unsigned long)pmd);
		pmd = NULL;
		failed = true;
		}