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author | Chuansheng Liu <chuansheng.liu@intel.com> | 2012-11-08 19:14:40 +0800 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2012-11-14 15:04:23 -0800 |
commit | ce2fcbd99cef580623116bb33531dbc3e6f690b0 (patch) | |
tree | baeea3fda4375556df4c54c1a6402f536c2a93f9 /drivers/base | |
parent | ecdca043ebe8e3172e0400d0966831e2e60870a0 (diff) | |
download | linux-stable-ce2fcbd99cef580623116bb33531dbc3e6f690b0.tar.gz linux-stable-ce2fcbd99cef580623116bb33531dbc3e6f690b0.tar.bz2 linux-stable-ce2fcbd99cef580623116bb33531dbc3e6f690b0.zip |
firmware loader: Fix the race FW_STATUS_DONE is followed by class_timeout
There is a race as below when calling request_firmware():
CPU1 CPU2
write 0 > loading
mutex_lock(&fw_lock)
...
set_bit FW_STATUS_DONE class_timeout is coming
set_bit FW_STATUS_ABORT
complete_all &completion
...
mutex_unlock(&fw_lock)
In this time, the bit FW_STATUS_DONE and FW_STATUS_ABORT are set,
and request_firmware() will return failure due to condition in
_request_firmware_load():
if (!buf->size || test_bit(FW_STATUS_ABORT, &buf->status))
retval = -ENOENT;
But from the above scenerio, it should be a successful requesting.
So we need judge if the bit FW_STATUS_DONE is already set before
calling fw_load_abort() in timeout function.
As Ming's proposal, we need change the timer into sched_work to
benefit from using &fw_lock mutex also.
Signed-off-by: liu chuansheng <chuansheng.liu@intel.com>
Acked-by: Ming Lei <ming.lei@canonical.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/base')
-rw-r--r-- | drivers/base/firmware_class.c | 24 |
1 files changed, 16 insertions, 8 deletions
diff --git a/drivers/base/firmware_class.c b/drivers/base/firmware_class.c index 8945f4e489ed..b44ed35ac38d 100644 --- a/drivers/base/firmware_class.c +++ b/drivers/base/firmware_class.c @@ -143,7 +143,7 @@ struct fw_cache_entry { }; struct firmware_priv { - struct timer_list timeout; + struct delayed_work timeout_work; bool nowait; struct device dev; struct firmware_buf *buf; @@ -667,11 +667,18 @@ static struct bin_attribute firmware_attr_data = { .write = firmware_data_write, }; -static void firmware_class_timeout(u_long data) +static void firmware_class_timeout_work(struct work_struct *work) { - struct firmware_priv *fw_priv = (struct firmware_priv *) data; + struct firmware_priv *fw_priv = container_of(work, + struct firmware_priv, timeout_work.work); + mutex_lock(&fw_lock); + if (test_bit(FW_STATUS_DONE, &(fw_priv->buf->status))) { + mutex_unlock(&fw_lock); + return; + } fw_load_abort(fw_priv); + mutex_unlock(&fw_lock); } static struct firmware_priv * @@ -690,8 +697,8 @@ fw_create_instance(struct firmware *firmware, const char *fw_name, fw_priv->nowait = nowait; fw_priv->fw = firmware; - setup_timer(&fw_priv->timeout, - firmware_class_timeout, (u_long) fw_priv); + INIT_DELAYED_WORK(&fw_priv->timeout_work, + firmware_class_timeout_work); f_dev = &fw_priv->dev; @@ -858,7 +865,9 @@ static int _request_firmware_load(struct firmware_priv *fw_priv, bool uevent, dev_dbg(f_dev->parent, "firmware: direct-loading" " firmware %s\n", buf->fw_id); + mutex_lock(&fw_lock); set_bit(FW_STATUS_DONE, &buf->status); + mutex_unlock(&fw_lock); complete_all(&buf->completion); direct_load = 1; goto handle_fw; @@ -894,15 +903,14 @@ static int _request_firmware_load(struct firmware_priv *fw_priv, bool uevent, dev_set_uevent_suppress(f_dev, false); dev_dbg(f_dev, "firmware: requesting %s\n", buf->fw_id); if (timeout != MAX_SCHEDULE_TIMEOUT) - mod_timer(&fw_priv->timeout, - round_jiffies_up(jiffies + timeout)); + schedule_delayed_work(&fw_priv->timeout_work, timeout); kobject_uevent(&fw_priv->dev.kobj, KOBJ_ADD); } wait_for_completion(&buf->completion); - del_timer_sync(&fw_priv->timeout); + cancel_delayed_work_sync(&fw_priv->timeout_work); handle_fw: mutex_lock(&fw_lock); |