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qlcnic: fix sleep-in-atomic-context bugs caused by msleep

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[ 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>
This commit is contained in:
Duoming Zhou 2022-11-23 18:06:42 +08:00 committed by Greg Kroah-Hartman
parent a88b8ffbcd
commit dd357c93b6
1 changed files with 2 additions and 2 deletions
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4
drivers/net/ethernet/qlogic/qlcnic/qlcnic_83xx_hw.c
View File

@ -2992,7 +2992,7 @@ 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) {
@ -3028,7 +3028,7 @@ 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)