| Message ID | 1423653159-20812-1-git-send-email-fdmanana@suse.com (mailing list archive) |
|---|---|
| State | Accepted |
| Headers | show |
On Wed, Feb 11, 2015 at 11:12:39AM +0000, Filipe Manana wrote: > We try to lock a mutex while the current task state is not TASK_RUNNING, > which results in the following warning when CONFIG_DEBUG_LOCK_ALLOC=y: > > [30736.772501] ------------[ cut here ]------------ > [30736.774545] WARNING: CPU: 9 PID: 19972 at kernel/sched/core.c:7300 __might_sleep+0x8b/0xa8() > [30736.783453] do not call blocking ops when !TASK_RUNNING; state=2 set at [<ffffffff8107499b>] prepare_to_wait+0x43/0x89 > [30736.786261] Modules linked in: dm_flakey dm_mod crc32c_generic btrfs xor raid6_pq nfsd auth_rpcgss oid_registry nfs_acl nfs lockd grace fscache sunrpc loop parport_pc psmouse parport pcspkr microcode serio_raw evdev processor thermal_sys i2c_piix4 i2c_core button ext4 crc16 jbd2 mbcache sg sr_mod cdrom sd_mod ata_generic virtio_scsi floppy ata_piix libata virtio_pci virtio_ring e1000 virtio scsi_mod > [30736.794323] CPU: 9 PID: 19972 Comm: fsstress Not tainted 3.19.0-rc7-btrfs-next-5+ #1 > [30736.795821] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.7.5-0-ge51488c-20140602_164612-nilsson.home.kraxel.org 04/01/2014 > [30736.798788] 0000000000000009 ffff88042743fbd8 ffffffff814248ed ffff88043d32f2d8 > [30736.800504] ffff88042743fc28 ffff88042743fc18 ffffffff81045338 0000000000000001 > [30736.802131] ffffffff81064514 ffffffff817c52d1 000000000000026d 0000000000000000 > [30736.803676] Call Trace: > [30736.804256] [<ffffffff814248ed>] dump_stack+0x4c/0x65 > [30736.805245] [<ffffffff81045338>] warn_slowpath_common+0xa1/0xbb > [30736.806360] [<ffffffff81064514>] ? __might_sleep+0x8b/0xa8 > [30736.807391] [<ffffffff81045398>] warn_slowpath_fmt+0x46/0x48 > [30736.808511] [<ffffffff8107499b>] ? prepare_to_wait+0x43/0x89 > [30736.809620] [<ffffffff8107499b>] ? prepare_to_wait+0x43/0x89 > [30736.810691] [<ffffffff81064514>] __might_sleep+0x8b/0xa8 > [30736.811703] [<ffffffff81426eaf>] mutex_lock_nested+0x2f/0x3a0 > [30736.812889] [<ffffffff8107bfa1>] ? trace_hardirqs_on_caller+0x18f/0x1ab > [30736.814138] [<ffffffff8107bfca>] ? trace_hardirqs_on+0xd/0xf > [30736.819878] [<ffffffffa038cfff>] wait_for_writer.isra.12+0x91/0xaa [btrfs] > [30736.821260] [<ffffffff810748bd>] ? signal_pending_state+0x31/0x31 > [30736.822410] [<ffffffffa0391f0a>] btrfs_sync_log+0x160/0x947 [btrfs] > [30736.823574] [<ffffffff8107bfa1>] ? trace_hardirqs_on_caller+0x18f/0x1ab > [30736.824847] [<ffffffff8107bfca>] ? trace_hardirqs_on+0xd/0xf > [30736.825972] [<ffffffffa036e555>] btrfs_sync_file+0x2b0/0x319 [btrfs] > [30736.827684] [<ffffffff8117901a>] vfs_fsync_range+0x21/0x23 > [30736.828932] [<ffffffff81179038>] vfs_fsync+0x1c/0x1e > [30736.829917] [<ffffffff8117928b>] do_fsync+0x34/0x4e > [30736.830862] [<ffffffff811794b3>] SyS_fsync+0x10/0x14 > [30736.831819] [<ffffffff8142a512>] system_call_fastpath+0x12/0x17 > [30736.832982] ---[ end trace c0b57df60d32ae5c ]--- > > Fix this my acquiring the mutex after calling finish_wait(), which sets the > task's state to TASK_RUNNING. Good catch. Reviewed-by: Liu Bo <bo.li.liu@oracle.com> Thanks, -liubo > > Signed-off-by: Filipe Manana <fdmanana@suse.com> > --- > fs/btrfs/tree-log.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/fs/btrfs/tree-log.c b/fs/btrfs/tree-log.c > index a266587..ea0431d 100644 > --- a/fs/btrfs/tree-log.c > +++ b/fs/btrfs/tree-log.c > @@ -2448,8 +2448,8 @@ static void wait_for_writer(struct btrfs_trans_handle *trans, > mutex_unlock(&root->log_mutex); > if (atomic_read(&root->log_writers)) > schedule(); > - mutex_lock(&root->log_mutex); > finish_wait(&root->log_writer_wait, &wait); > + mutex_lock(&root->log_mutex); > } > } > > -- > 2.1.3 > > -- > To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/fs/btrfs/tree-log.c b/fs/btrfs/tree-log.c index a266587..ea0431d 100644 --- a/fs/btrfs/tree-log.c +++ b/fs/btrfs/tree-log.c @@ -2448,8 +2448,8 @@ static void wait_for_writer(struct btrfs_trans_handle *trans, mutex_unlock(&root->log_mutex); if (atomic_read(&root->log_writers)) schedule(); - mutex_lock(&root->log_mutex); finish_wait(&root->log_writer_wait, &wait); + mutex_lock(&root->log_mutex); } }
We try to lock a mutex while the current task state is not TASK_RUNNING, which results in the following warning when CONFIG_DEBUG_LOCK_ALLOC=y: [30736.772501] ------------[ cut here ]------------ [30736.774545] WARNING: CPU: 9 PID: 19972 at kernel/sched/core.c:7300 __might_sleep+0x8b/0xa8() [30736.783453] do not call blocking ops when !TASK_RUNNING; state=2 set at [<ffffffff8107499b>] prepare_to_wait+0x43/0x89 [30736.786261] Modules linked in: dm_flakey dm_mod crc32c_generic btrfs xor raid6_pq nfsd auth_rpcgss oid_registry nfs_acl nfs lockd grace fscache sunrpc loop parport_pc psmouse parport pcspkr microcode serio_raw evdev processor thermal_sys i2c_piix4 i2c_core button ext4 crc16 jbd2 mbcache sg sr_mod cdrom sd_mod ata_generic virtio_scsi floppy ata_piix libata virtio_pci virtio_ring e1000 virtio scsi_mod [30736.794323] CPU: 9 PID: 19972 Comm: fsstress Not tainted 3.19.0-rc7-btrfs-next-5+ #1 [30736.795821] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.7.5-0-ge51488c-20140602_164612-nilsson.home.kraxel.org 04/01/2014 [30736.798788] 0000000000000009 ffff88042743fbd8 ffffffff814248ed ffff88043d32f2d8 [30736.800504] ffff88042743fc28 ffff88042743fc18 ffffffff81045338 0000000000000001 [30736.802131] ffffffff81064514 ffffffff817c52d1 000000000000026d 0000000000000000 [30736.803676] Call Trace: [30736.804256] [<ffffffff814248ed>] dump_stack+0x4c/0x65 [30736.805245] [<ffffffff81045338>] warn_slowpath_common+0xa1/0xbb [30736.806360] [<ffffffff81064514>] ? __might_sleep+0x8b/0xa8 [30736.807391] [<ffffffff81045398>] warn_slowpath_fmt+0x46/0x48 [30736.808511] [<ffffffff8107499b>] ? prepare_to_wait+0x43/0x89 [30736.809620] [<ffffffff8107499b>] ? prepare_to_wait+0x43/0x89 [30736.810691] [<ffffffff81064514>] __might_sleep+0x8b/0xa8 [30736.811703] [<ffffffff81426eaf>] mutex_lock_nested+0x2f/0x3a0 [30736.812889] [<ffffffff8107bfa1>] ? trace_hardirqs_on_caller+0x18f/0x1ab [30736.814138] [<ffffffff8107bfca>] ? trace_hardirqs_on+0xd/0xf [30736.819878] [<ffffffffa038cfff>] wait_for_writer.isra.12+0x91/0xaa [btrfs] [30736.821260] [<ffffffff810748bd>] ? signal_pending_state+0x31/0x31 [30736.822410] [<ffffffffa0391f0a>] btrfs_sync_log+0x160/0x947 [btrfs] [30736.823574] [<ffffffff8107bfa1>] ? trace_hardirqs_on_caller+0x18f/0x1ab [30736.824847] [<ffffffff8107bfca>] ? trace_hardirqs_on+0xd/0xf [30736.825972] [<ffffffffa036e555>] btrfs_sync_file+0x2b0/0x319 [btrfs] [30736.827684] [<ffffffff8117901a>] vfs_fsync_range+0x21/0x23 [30736.828932] [<ffffffff81179038>] vfs_fsync+0x1c/0x1e [30736.829917] [<ffffffff8117928b>] do_fsync+0x34/0x4e [30736.830862] [<ffffffff811794b3>] SyS_fsync+0x10/0x14 [30736.831819] [<ffffffff8142a512>] system_call_fastpath+0x12/0x17 [30736.832982] ---[ end trace c0b57df60d32ae5c ]--- Fix this my acquiring the mutex after calling finish_wait(), which sets the task's state to TASK_RUNNING. Signed-off-by: Filipe Manana <fdmanana@suse.com> --- fs/btrfs/tree-log.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)