Re: [PATCH] net/qla3xxx: fix schedule while atomic in ql_sem_spinlock

On Thu, May 20, 2021 at 3:26 AM David Miller [off-list ref] wrote:

From: Zheyu Ma <redacted>
Date: Wed, 19 May 2021 06:49:14 +0000

quoted

When calling the 'ql_sem_spinlock', the driver has already acquired the
spin lock, so the driver should not call 'ssleep' in atomic context.

This bug can be fixed by unlocking before calling 'ssleep'.

 ...

quoted

diff --git a/drivers/net/ethernet/qlogic/qla3xxx.c b/drivers/net/ethernet/qlogic/qla3xxx.c
index 214e347097a7..af7c142a066f 100644
--- a/drivers/net/ethernet/qlogic/qla3xxx.c
+++ b/drivers/net/ethernet/qlogic/qla3xxx.c

@@ -114,7 +114,9 @@ static int ql_sem_spinlock(struct ql3_adapter *qdev,
              value = readl(&port_regs->CommonRegs.semaphoreReg);
              if ((value & (sem_mask >> 16)) == sem_bits)
                      return 0;
+             spin_unlock_irq(&qdev->hw_lock);
              ssleep(1);
+             spin_lock_irq(&qdev->hw_lock);
      } while (--seconds);
      return -1;
 }

Are you sure dropping the lock like this dos not introduce a race condition?

Thank you.

Thanks for your comment, it is indeed inappropriate to release the
lock here, I will resend the second version of the patch.

Zheyu Ma