[BUG] fs: jffs2: possible sleep-in-atomic-context bugs in jffs2_iget
The kernel may sleep with holding a spinlock. The function call paths (from bottom to top) in Linux-4.16 are: [FUNC] schedule fs/inode.c, 1916: schedule in __wait_on_freeing_inode fs/inode.c, 826: __wait_on_freeing_inode in find_inode_fast fs/inode.c, 1107: find_inode_fast in iget_locked fs/jffs2/fs.c, 263: iget_locked in jffs2_iget fs/jffs2/fs.c, 665: jffs2_iget in jffs2_gc_fetch_inode fs/jffs2/wbuf.c, 505: jffs2_gc_fetch_inode in jffs2_wbuf_recover fs/jffs2/wbuf.c, 462: spin_lock in jffs2_wbuf_recover [FUNC] mutex_lock_nested fs/jffs2/fs.c, 273: mutex_lock_nested in jffs2_iget fs/jffs2/fs.c, 665: jffs2_iget in jffs2_gc_fetch_inode fs/jffs2/wbuf.c, 505: jffs2_gc_fetch_inode in jffs2_wbuf_recover fs/jffs2/wbuf.c, 462: spin_lock in jffs2_wbuf_recover I do not find a good way to fix, so I only report. Maybe the spinlock should be released before calling jffs2_iget(), and then be acquired again. This is found by my static analysis tool (DSAC). Thanks, Jia-Ju Bai
[BUG] fs: jffs2: possible sleep-in-atomic-context bugs in jffs2_iget
The kernel may sleep with holding a spinlock. The function call paths (from bottom to top) in Linux-4.16 are: [FUNC] schedule fs/inode.c, 1916: schedule in __wait_on_freeing_inode fs/inode.c, 826: __wait_on_freeing_inode in find_inode_fast fs/inode.c, 1107: find_inode_fast in iget_locked fs/jffs2/fs.c, 263: iget_locked in jffs2_iget fs/jffs2/fs.c, 665: jffs2_iget in jffs2_gc_fetch_inode fs/jffs2/wbuf.c, 505: jffs2_gc_fetch_inode in jffs2_wbuf_recover fs/jffs2/wbuf.c, 462: spin_lock in jffs2_wbuf_recover [FUNC] mutex_lock_nested fs/jffs2/fs.c, 273: mutex_lock_nested in jffs2_iget fs/jffs2/fs.c, 665: jffs2_iget in jffs2_gc_fetch_inode fs/jffs2/wbuf.c, 505: jffs2_gc_fetch_inode in jffs2_wbuf_recover fs/jffs2/wbuf.c, 462: spin_lock in jffs2_wbuf_recover I do not find a good way to fix, so I only report. Maybe the spinlock should be released before calling jffs2_iget(), and then be acquired again. This is found by my static analysis tool (DSAC). Thanks, Jia-Ju Bai