qlcnic: fix sleep-in-atomic-context bugs caused by msleep
authorDuoming Zhou <duoming@zju.edu.cn>
Wed, 23 Nov 2022 10:06:42 +0000 (18:06 +0800)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Thu, 8 Dec 2022 10:28:40 +0000 (11:28 +0100)
[ Upstream commit 8dbd6e4ce1b9c527921643d9e34f188a10d4e893 ]

The watchdog timer is used to monitor whether the process
of transmitting data is timeout. If we use qlcnic driver,
the dev_watchdog() that is the timer handler of watchdog
timer will call qlcnic_tx_timeout() to process the timeout.
But the qlcnic_tx_timeout() calls msleep(), as a result,
the sleep-in-atomic-context bugs will happen. The processes
are shown below:

   (atomic context)
dev_watchdog
  qlcnic_tx_timeout
    qlcnic_83xx_idc_request_reset
      qlcnic_83xx_lock_driver
        msleep

---------------------------

   (atomic context)
dev_watchdog
  qlcnic_tx_timeout
    qlcnic_83xx_idc_request_reset
      qlcnic_83xx_lock_driver
        qlcnic_83xx_recover_driver_lock
          msleep

Fix by changing msleep() to mdelay(), the mdelay() is
busy-waiting and the bugs could be mitigated.

Fixes: 629263acaea3 ("qlcnic: 83xx CNA inter driver communication mechanism")
Signed-off-by: Duoming Zhou <duoming@zju.edu.cn>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
drivers/net/ethernet/qlogic/qlcnic/qlcnic_83xx_hw.c

index bd06076..2fd5c6f 100644 (file)
@@ -2991,7 +2991,7 @@ static void qlcnic_83xx_recover_driver_lock(struct qlcnic_adapter *adapter)
                QLCWRX(adapter->ahw, QLC_83XX_RECOVER_DRV_LOCK, val);
                dev_info(&adapter->pdev->dev,
                         "%s: lock recovery initiated\n", __func__);
-               msleep(QLC_83XX_DRV_LOCK_RECOVERY_DELAY);
+               mdelay(QLC_83XX_DRV_LOCK_RECOVERY_DELAY);
                val = QLCRDX(adapter->ahw, QLC_83XX_RECOVER_DRV_LOCK);
                id = ((val >> 2) & 0xF);
                if (id == adapter->portnum) {
@@ -3027,7 +3027,7 @@ int qlcnic_83xx_lock_driver(struct qlcnic_adapter *adapter)
                if (status)
                        break;
 
-               msleep(QLC_83XX_DRV_LOCK_WAIT_DELAY);
+               mdelay(QLC_83XX_DRV_LOCK_WAIT_DELAY);
                i++;
 
                if (i == 1)