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authorYangtao Li <frank.li@vivo.com>2023-03-20 20:22:18 +0300
committerJaegeuk Kim <jaegeuk@kernel.org>2023-03-30 01:17:39 +0300
commitbabedcbac164cec970872b8097401ca913a80e61 (patch)
tree6d976487e2d8a41813848cb8e93d9e46b9feb7a2 /fs/f2fs/compress.c
parentc948be797da8ddbb1ec2f5cccad1c8629c69db79 (diff)
downloadlinux-babedcbac164cec970872b8097401ca913a80e61.tar.xz
f2fs: compress: fix to call f2fs_wait_on_page_writeback() in f2fs_write_raw_pages()
BUG_ON() will be triggered when writing files concurrently, because the same page is writtenback multiple times. 1597 void folio_end_writeback(struct folio *folio) 1598 { ...... 1618 if (!__folio_end_writeback(folio)) 1619 BUG(); ...... 1625 } kernel BUG at mm/filemap.c:1619! Call Trace: <TASK> f2fs_write_end_io+0x1a0/0x370 blk_update_request+0x6c/0x410 blk_mq_end_request+0x15/0x130 blk_complete_reqs+0x3c/0x50 __do_softirq+0xb8/0x29b ? sort_range+0x20/0x20 run_ksoftirqd+0x19/0x20 smpboot_thread_fn+0x10b/0x1d0 kthread+0xde/0x110 ? kthread_complete_and_exit+0x20/0x20 ret_from_fork+0x22/0x30 </TASK> Below is the concurrency scenario: [Process A] [Process B] [Process C] f2fs_write_raw_pages() - redirty_page_for_writepage() - unlock page() f2fs_do_write_data_page() - lock_page() - clear_page_dirty_for_io() - set_page_writeback() [1st writeback] ..... - unlock page() generic_perform_write() - f2fs_write_begin() - wait_for_stable_page() - f2fs_write_end() - set_page_dirty() - lock_page() - f2fs_do_write_data_page() - set_page_writeback() [2st writeback] This problem was introduced by the previous commit 7377e853967b ("f2fs: compress: fix potential deadlock of compress file"). All pagelocks were released in f2fs_write_raw_pages(), but whether the page was in the writeback state was ignored in the subsequent writing process. Let's fix it by waiting for the page to writeback before writing. Cc: Christoph Hellwig <hch@lst.de> Fixes: 4c8ff7095bef ("f2fs: support data compression") Fixes: 7377e853967b ("f2fs: compress: fix potential deadlock of compress file") Signed-off-by: Qi Han <hanqi@vivo.com> Signed-off-by: Yangtao Li <frank.li@vivo.com> Reviewed-by: Chao Yu <chao@kernel.org> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Diffstat (limited to 'fs/f2fs/compress.c')
-rw-r--r--fs/f2fs/compress.c6
1 files changed, 6 insertions, 0 deletions
diff --git a/fs/f2fs/compress.c b/fs/f2fs/compress.c
index 93fec1d37899..9b7149534a58 100644
--- a/fs/f2fs/compress.c
+++ b/fs/f2fs/compress.c
@@ -1456,6 +1456,12 @@ continue_unlock:
if (!PageDirty(cc->rpages[i]))
goto continue_unlock;
+ if (PageWriteback(cc->rpages[i])) {
+ if (wbc->sync_mode == WB_SYNC_NONE)
+ goto continue_unlock;
+ f2fs_wait_on_page_writeback(cc->rpages[i], DATA, true, true);
+ }
+
if (!clear_page_dirty_for_io(cc->rpages[i]))
goto continue_unlock;