[PATCH v2 2/3] firmware loader: fix hung task warning dump
From: Kweh Hock Leong
Date: Sun Nov 02 2014 - 22:04:38 EST
From: "Kweh, Hock Leong" <hock.leong.kweh@xxxxxxxxx>
When using request_firmware_nowait() with FW_ACTION_NOHOTPLUG param to
expose user helper interface, if the user do not react immediately, after
120 seconds there will be a hung task warning message dumped as below:
[ 3000.784235] INFO: task kworker/0:0:8259 blocked for more than 120 seconds.
[ 3000.791281] Tainted: G E 3.16.0-rc1-yocto-standard #41
[ 3000.798082] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[ 3000.806072] kworker/0:0 D cd0075c8 0 8259 2 0x00000000
[ 3000.812765] Workqueue: events request_firmware_work_func
[ 3000.818253] cd375e18 00000046 0000000e cd0075c8 000000f0 cd40ea00 cd375fec 1b883e89
[ 3000.826374] 0000026b cd40ea00 80000000 00000001 cd0075c8 00000000 cd375de4 c119917f
[ 3000.834492] cd563360 cd375df4 c119a0ab cd563360 00000000 cd375e24 c119a1d6 00000000
[ 3000.842616] Call Trace:
[ 3000.845252] [<c119917f>] ? kernfs_next_descendant_post+0x3f/0x50
[ 3000.851543] [<c119a0ab>] ? kernfs_activate+0x6b/0xc0
[ 3000.856790] [<c119a1d6>] ? kernfs_add_one+0xd6/0x130
[ 3000.862047] [<c15fdb02>] schedule+0x22/0x60
[ 3000.866548] [<c15fd195>] schedule_timeout+0x175/0x1d0
[ 3000.871887] [<c119b391>] ? __kernfs_create_file+0x71/0xa0
[ 3000.877574] [<c119bb9a>] ? sysfs_add_file_mode_ns+0xaa/0x180
[ 3000.883533] [<c15fe84f>] wait_for_completion+0x6f/0xb0
[ 3000.888961] [<c1065200>] ? wake_up_process+0x40/0x40
[ 3000.894219] [<c13cb600>] _request_firmware+0x750/0x9f0
[ 3000.899666] [<c1382a7f>] ? n_tty_receive_buf2+0x1f/0x30
[ 3000.905200] [<c13cba02>] request_firmware_work_func+0x22/0x50
[ 3000.911235] [<c10550d2>] process_one_work+0x122/0x380
[ 3000.916571] [<c1055859>] worker_thread+0xf9/0x470
[ 3000.921555] [<c1055760>] ? create_and_start_worker+0x50/0x50
[ 3000.927497] [<c1055760>] ? create_and_start_worker+0x50/0x50
[ 3000.933448] [<c105a5ff>] kthread+0x9f/0xc0
[ 3000.937850] [<c15ffd40>] ret_from_kernel_thread+0x20/0x30
[ 3000.943548] [<c105a560>] ? kthread_worker_fn+0x100/0x100
This patch change the wait_for_completion() function call to
wait_for_completion_interruptible() function call for solving the issue.
Cc: Matt Fleming <matt.fleming@xxxxxxxxx>
Signed-off-by: Kweh, Hock Leong <hock.leong.kweh@xxxxxxxxx>
---
drivers/base/firmware_class.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/base/firmware_class.c b/drivers/base/firmware_class.c
index a238a46..639eeff 100644
--- a/drivers/base/firmware_class.c
+++ b/drivers/base/firmware_class.c
@@ -908,7 +908,7 @@ static int _request_firmware_load(struct firmware_priv *fw_priv,
kobject_uevent(&fw_priv->dev.kobj, KOBJ_ADD);
}
- wait_for_completion(&buf->completion);
+ retval = wait_for_completion_interruptible(&buf->completion);
cancel_delayed_work_sync(&fw_priv->timeout_work);
if (!buf->data)
@@ -985,7 +985,7 @@ static int sync_cached_firmware_buf(struct firmware_buf *buf)
break;
}
mutex_unlock(&fw_lock);
- wait_for_completion(&buf->completion);
+ ret = wait_for_completion_interruptible(&buf->completion);
mutex_lock(&fw_lock);
}
mutex_unlock(&fw_lock);
--
1.7.9.5
--
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/