https://github.com/torvalds/linux
Revision aa9bca05a467c61dcea4142b2877d5392de5bdce authored by Weijie Yang on 16 October 2013, 20:46:54 UTC, committed by Linus Torvalds on 17 October 2013, 04:35:52 UTC
zswap_tree is not freed when swapoff, and it got re-kmalloced in swapon, so a memory leak occurs. Free the memory of zswap_tree in zswap_frontswap_invalidate_area(). Signed-off-by: Weijie Yang <weijie.yang@samsung.com> Reviewed-by: Bob Liu <bob.liu@oracle.com> Cc: Minchan Kim <minchan@kernel.org> Reviewed-by: Minchan Kim <minchan@kernel.org> Cc: <stable@vger.kernel.org> From: Weijie Yang <weijie.yang@samsung.com> Subject: mm/zswap: bugfix: memory leak when invalidate and reclaim occur concurrently Consider the following scenario: thread 0: reclaim entry x (get refcount, but not call zswap_get_swap_cache_page) thread 1: call zswap_frontswap_invalidate_page to invalidate entry x. finished, entry x and its zbud is not freed as its refcount != 0 now, the swap_map[x] = 0 thread 0: now call zswap_get_swap_cache_page swapcache_prepare return -ENOENT because entry x is not used any more zswap_get_swap_cache_page return ZSWAP_SWAPCACHE_NOMEM zswap_writeback_entry do nothing except put refcount Now, the memory of zswap_entry x and its zpage leak. Modify: - check the refcount in fail path, free memory if it is not referenced. - use ZSWAP_SWAPCACHE_FAIL instead of ZSWAP_SWAPCACHE_NOMEM as the fail path can be not only caused by nomem but also by invalidate. [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Weijie Yang <weijie.yang@samsung.com> Reviewed-by: Bob Liu <bob.liu@oracle.com> Cc: Minchan Kim <minchan@kernel.org> Cc: <stable@vger.kernel.org> Acked-by: Seth Jennings <sjenning@linux.vnet.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
1 parent e9cdd6e
Tip revision: aa9bca05a467c61dcea4142b2877d5392de5bdce authored by Weijie Yang on 16 October 2013, 20:46:54 UTC
mm/zswap: bugfix: memory leak when re-swapon
mm/zswap: bugfix: memory leak when re-swapon
Tip revision: aa9bca0
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include | ||
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lib | ||
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COPYING | -rw-r--r-- | 18.3 KB |
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