Re: [syzbot] Re: [syzbot] [ocfs2?] kernel BUG in ocfs2_iget

[syzbot <syzbot+5bdd4953bc58c8fbd6eb@syzkaller.appspotmail.com>]

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Subject: Re: [syzbot] [ocfs2?] kernel BUG in ocfs2_iget
Author: lizhi.xu@windriver.com

clean dirty for the release inode, stop to worker wb it again.

#syz test: upstream d07b43284ab3

diff --git a/fs/ocfs2/buffer_head_io.c b/fs/ocfs2/buffer_head_io.c
index cdb9b9bdea1f..a33d06069968 100644
--- a/fs/ocfs2/buffer_head_io.c
+++ b/fs/ocfs2/buffer_head_io.c
@@ -115,6 +115,7 @@ int ocfs2_read_blocks_sync(struct ocfs2_super *osb, u64 block,
 		}
 		bh = bhs[i];
 
+		printk("jbd: %d, dirty: %d, i: %d, bh: %p, %s\n", buffer_jbd(bh), buffer_dirty(bh), i, bh, __func__);
 		if (buffer_jbd(bh)) {
 			trace_ocfs2_read_blocks_sync_jbd(
 					(unsigned long long)bh->b_blocknr);
@@ -148,6 +149,8 @@ int ocfs2_read_blocks_sync(struct ocfs2_super *osb, u64 block,
 		get_bh(bh); /* for end_buffer_read_sync() */
 		bh->b_end_io = end_buffer_read_sync;
 		submit_bh(REQ_OP_READ, bh);
+		printk("bio, jbd: %d, dirty: %d, i: %d, bh: %p, buflocked: %d, status: %d, %s\n", buffer_jbd(bh),
+			buffer_dirty(bh), i, bh, buffer_locked(bh), status, __func__);
 	}
 
 read_failure:
@@ -170,9 +173,15 @@ int ocfs2_read_blocks_sync(struct ocfs2_super *osb, u64 block,
 			continue;
 		}
 
+		printk("rf, jbd: %d, dirty: %d, i: %d, bh: %p, buflocked: %d, status: %d, %s\n", buffer_jbd(bh),
+			buffer_dirty(bh), i, bh, buffer_locked(bh), status, __func__);
 		/* No need to wait on the buffer if it's managed by JBD. */
-		if (!buffer_jbd(bh))
+		if (!buffer_jbd(bh)) {
+			if (!buffer_locked(bh) && bh->b_end_io == end_buffer_read_sync)
+				lock_buffer(bh);
+
 			wait_on_buffer(bh);
+		}
 
 		if (!buffer_uptodate(bh)) {
 			/* Status won't be cleared from here on out,