fuse try to freeze with lock held

[Liu, Chuansheng]

Hit the below warning when enabling the CONFIG_DEBUG_LOCK_ALLOC,
__fuse_request_send == >
request_wait_answer == >
wait_event_freezable == >
try_to_freeze()

But here the inode->i_mutex is hold yet in vfs_readdir().

Could anyone give some help? Thanks.


[ 3148.552435] Freezing user space processes ... [ 3148.557781]
[ 3148.559505] =====================================
[ 3148.564803] [ BUG: du/21716 still has locks held! ]
[ 3148.570319] 3.10.16-261493-g1308ae2 #8 Tainted: G        W  O

[ 3148.586082]  #0:  (&type->i_mutex_dir_key#3){......}, at: [<c1341dc6>] vfs_readdir+0x66/0xd0
[ 3148.595967]
[ 3148.595967] stack backtrace:
[ 3148.600875] CPU: 2 PID: 21716 Comm: du Tainted: G        W  O 3.10.16-261493-g1308ae2 #8
[ 3148.609973]  d7e494e0 d7e494e0 cca6be78 c1b0fccb cca6be90 c12913f1 c1db2cc5 d7e497e4
[ 3148.618872]  000054d4 cca6beac cca6becc c1440d8b d7e494e0 f2557800 f12acedc 00000000
[ 3148.627747]  00000000 00000000 d7e494e0 c125f100 cca6beb8 cca6beb8 f12ace40 f2557800
[ 3148.636614] Call Trace:
[ 3148.639395]  [<c1b0fccb>] dump_stack+0x16/0x18
[ 3148.644375]  [<c12913f1>] debug_check_no_locks_held+0x91/0xa0
[ 3148.650862]  [<c1440d8b>] __fuse_request_send+0x14b/0x320
[ 3148.656961]  [<c125f100>] ? wake_up_bit+0x30/0x30
[ 3148.662242]  [<c1440f71>] fuse_request_send+0x11/0x20
[ 3148.667941]  [<c14455a9>] fuse_readdir+0x109/0x690
[ 3148.673327]  [<c1341dc6>] ? vfs_readdir+0x66/0xd0
[ 3148.678636]  [<c1b1bec5>] ? sub_preempt_count+0x45/0x60
[ 3148.684503]  [<c1b15694>] ? mutex_lock_killable_nested+0x214/0x300
[ 3148.691457]  [<c1341b60>] ? SyS_ioctl+0x90/0x90
[ 3148.696553]  [<c1341dc6>] ? vfs_readdir+0x66/0xd0
[ 3148.701857]  [<c1341b60>] ? SyS_ioctl+0x90/0x90

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/