[PATCH v2] net/qla3xxx: fix schedule while atomic in ql_sem_spinlock

[PATCH v2] net/qla3xxx: fix schedule while atomic in ql_sem_spinlock

[Zheyu Ma]

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 using 'mdelay' instead of 'ssleep'.

The KASAN's log reveals it:

[    3.238124 ] BUG: scheduling while atomic: swapper/0/1/0x00000002
[    3.238748 ] 2 locks held by swapper/0/1:
[    3.239151 ]  #0: ffff88810177b240 (&dev->mutex){....}-{3:3}, at:
__device_driver_lock+0x41/0x60
[    3.240026 ]  #1: ffff888107c60e28 (&qdev->hw_lock){....}-{2:2}, at:
ql3xxx_probe+0x2aa/0xea0
[    3.240873 ] Modules linked in:
[    3.241187 ] irq event stamp: 460854
[    3.241541 ] hardirqs last  enabled at (460853): [<ffffffff843051bf>]
_raw_spin_unlock_irqrestore+0x4f/0x70
[    3.242245 ] hardirqs last disabled at (460854): [<ffffffff843058ca>]
_raw_spin_lock_irqsave+0x2a/0x70
[    3.242245 ] softirqs last  enabled at (446076): [<ffffffff846002e4>]
__do_softirq+0x2e4/0x4b1
[    3.242245 ] softirqs last disabled at (446069): [<ffffffff811ba5e0>]
irq_exit_rcu+0x100/0x110
[    3.242245 ] Preemption disabled at:
[    3.242245 ] [<ffffffff828ca5ba>] ql3xxx_probe+0x2aa/0xea0
[    3.242245 ] Kernel panic - not syncing: scheduling while atomic
[    3.242245 ] CPU: 2 PID: 1 Comm: swapper/0 Not tainted
5.13.0-rc1-00145
-gee7dc339169-dirty #16
[    3.242245 ] Call Trace:
[    3.242245 ]  dump_stack+0xba/0xf5
[    3.242245 ]  ? ql3xxx_probe+0x1f0/0xea0
[    3.242245 ]  panic+0x15a/0x3f2
[    3.242245 ]  ? vprintk+0x76/0x150
[    3.242245 ]  ? ql3xxx_probe+0x2aa/0xea0
[    3.242245 ]  __schedule_bug+0xae/0xe0
[    3.242245 ]  __schedule+0x72e/0xa00
[    3.242245 ]  schedule+0x43/0xf0
[    3.242245 ]  schedule_timeout+0x28b/0x500
[    3.242245 ]  ? del_timer_sync+0xf0/0xf0
[    3.242245 ]  ? msleep+0x2f/0x70
[    3.242245 ]  msleep+0x59/0x70
[    3.242245 ]  ql3xxx_probe+0x307/0xea0
[    3.242245 ]  ? _raw_spin_unlock_irqrestore+0x3a/0x70
[    3.242245 ]  ? pci_device_remove+0x110/0x110
[    3.242245 ]  local_pci_probe+0x45/0xa0
[    3.242245 ]  pci_device_probe+0x12b/0x1d0
[    3.242245 ]  really_probe+0x2a9/0x610
[    3.242245 ]  driver_probe_device+0x90/0x1d0
[    3.242245 ]  ? mutex_lock_nested+0x1b/0x20
[    3.242245 ]  device_driver_attach+0x68/0x70
[    3.242245 ]  __driver_attach+0x124/0x1b0
[    3.242245 ]  ? device_driver_attach+0x70/0x70
[    3.242245 ]  bus_for_each_dev+0xbb/0x110
[    3.242245 ]  ? rdinit_setup+0x45/0x45
[    3.242245 ]  driver_attach+0x27/0x30
[    3.242245 ]  bus_add_driver+0x1eb/0x2a0
[    3.242245 ]  driver_register+0xa9/0x180
[    3.242245 ]  __pci_register_driver+0x82/0x90
[    3.242245 ]  ? yellowfin_init+0x25/0x25
[    3.242245 ]  ql3xxx_driver_init+0x23/0x25
[    3.242245 ]  do_one_initcall+0x7f/0x3d0
[    3.242245 ]  ? rdinit_setup+0x45/0x45
[    3.242245 ]  ? rcu_read_lock_sched_held+0x4f/0x80
[    3.242245 ]  kernel_init_freeable+0x2aa/0x301
[    3.242245 ]  ? rest_init+0x2c0/0x2c0
[    3.242245 ]  kernel_init+0x18/0x190
[    3.242245 ]  ? rest_init+0x2c0/0x2c0
[    3.242245 ]  ? rest_init+0x2c0/0x2c0
[    3.242245 ]  ret_from_fork+0x1f/0x30
[    3.242245 ] Dumping ftrace buffer:
[    3.242245 ]    (ftrace buffer empty)
[    3.242245 ] Kernel Offset: disabled
[    3.242245 ] Rebooting in 1 seconds.

Reported-by: Zheyu Ma <zheyuma97@gmail.com>
Signed-off-by: Zheyu Ma <zheyuma97@gmail.com>
---
Changes in v2:
    - Use 'mdelay' instead of releasing the lock before the 'ssleep'.
---
 drivers/net/ethernet/qlogic/qla3xxx.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/qlogic/qla3xxx.c b/drivers/net/ethernet/qlogic/qla3xxx.c
index 214e347097a7..2376b2729633 100644
--- a/drivers/net/ethernet/qlogic/qla3xxx.c
+++ b/drivers/net/ethernet/qlogic/qla3xxx.c
@@ -114,7 +114,7 @@ static int ql_sem_spinlock(struct ql3_adapter *qdev,
 		value = readl(&port_regs->CommonRegs.semaphoreReg);
 		if ((value & (sem_mask >> 16)) == sem_bits)
 			return 0;
-		ssleep(1);
+		mdelay(1000);
 	} while (--seconds);
 	return -1;
 }
-- 
2.17.1

Re: [PATCH v2] net/qla3xxx: fix schedule while atomic in ql_sem_spinlock

[patchwork-bot+netdevbpf]

Hello:

This patch was applied to netdev/net.git (refs/heads/master):

On Thu, 20 May 2021 12:32:36 +0000 you wrote:
> 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 using 'mdelay' instead of 'ssleep'.
> 
> The KASAN's log reveals it:
> 
> [...]

Here is the summary with links:
  - [v2] net/qla3xxx: fix schedule while atomic in ql_sem_spinlock
    https://git.kernel.org/netdev/net/c/13a6f3153922

You are awesome, thank you!
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