[PATCH] [fuse] alloc_page nofs avoid deadlock

[chenguanyou]

ABA deadlock

PID: 17172 TASK: ffffffc0c162c000 CPU: 6 COMMAND: "Thread-21"
0 [ffffff802d16b400] __switch_to at ffffff8008086a4c
1 [ffffff802d16b470] __schedule at ffffff80091ffe58
2 [ffffff802d16b4d0] schedule at ffffff8009200348
3 [ffffff802d16b4f0] bit_wait at ffffff8009201098
4 [ffffff802d16b510] __wait_on_bit at ffffff8009200a34
5 [ffffff802d16b5b0] inode_wait_for_writeback at ffffff800830e1e8
6 [ffffff802d16b5e0] evict at ffffff80082fb15c
7 [ffffff802d16b620] iput at ffffff80082f9270
8 [ffffff802d16b680] dentry_unlink_inode at ffffff80082f4c90
9 [ffffff802d16b6a0] __dentry_kill at ffffff80082f1710
10 [ffffff802d16b6d0] shrink_dentry_list at ffffff80082f1c34
11 [ffffff802d16b750] prune_dcache_sb at ffffff80082f18a8
12 [ffffff802d16b770] super_cache_scan at ffffff80082d55ac
13 [ffffff802d16b860] shrink_slab at ffffff8008266170
14 [ffffff802d16b900] shrink_node at ffffff800826b420
15 [ffffff802d16b980] do_try_to_free_pages at ffffff8008268460
16 [ffffff802d16ba60] try_to_free_pages at ffffff80082680d0
17 [ffffff802d16bbe0] __alloc_pages_nodemask at ffffff8008256514
18 [ffffff802d16bc60] fuse_copy_fill at ffffff8008438268
19 [ffffff802d16bd00] fuse_dev_do_read at ffffff8008437654
20 [ffffff802d16bdc0] fuse_dev_splice_read at ffffff8008436f40
21 [ffffff802d16be60] sys_splice at ffffff8008315d18
22 [ffffff802d16bff0] __sys_trace at ffffff8008084014

PID: 9652 TASK: ffffffc0c9ce0000 CPU: 4 COMMAND: "kworker/u16:8"
0 [ffffff802e793650] __switch_to at ffffff8008086a4c
1 [ffffff802e7936c0] __schedule at ffffff80091ffe58
2 [ffffff802e793720] schedule at ffffff8009200348
3 [ffffff802e793770] __fuse_request_send at ffffff8008435760
4 [ffffff802e7937b0] fuse_simple_request at ffffff8008435b14
5 [ffffff802e793930] fuse_flush_times at ffffff800843a7a0
6 [ffffff802e793950] fuse_write_inode at ffffff800843e4dc
7 [ffffff802e793980] __writeback_single_inode at ffffff8008312740
8 [ffffff802e793aa0] writeback_sb_inodes at ffffff80083117e4
9 [ffffff802e793b00] __writeback_inodes_wb at ffffff8008311d98
10 [ffffff802e793c00] wb_writeback at ffffff8008310cfc
11 [ffffff802e793d00] wb_workfn at ffffff800830e4a8
12 [ffffff802e793d90] process_one_work at ffffff80080e4fac
13 [ffffff802e793e00] worker_thread at ffffff80080e5670
14 [ffffff802e793e60] kthread at ffffff80080eb650

Signed-off-by: chenguanyou <chenguanyou@xxxxxxxxxx>
---
 fs/fuse/dev.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/fuse/dev.c b/fs/fuse/dev.c
index c0fee830a34e..d36125ff0405 100644
--- a/fs/fuse/dev.c
+++ b/fs/fuse/dev.c
@@ -721,7 +721,7 @@ static int fuse_copy_fill(struct fuse_copy_state *cs)
 			if (cs->nr_segs >= cs->pipe->max_usage)
 				return -EIO;
 
-			page = alloc_page(GFP_HIGHUSER);
+			page = alloc_page(GFP_NOFS | __GFP_HIGHMEM);
 			if (!page)
 				return -ENOMEM;
 
-- 
2.17.1