[BUG] scsi/fcoe: Sleep-in-atomic bugs in fcoe driver

[BUG] scsi/fcoe: Sleep-in-atomic bugs in fcoe driver

[Jia-Ju Bai]

According to fcoe_ctlr.c, the driver may sleep under a RCU lock,
and the function call paths are:
fcoe_ctlr_disc_stop_locked (acquire the RCU lock)
   fc_rport_logoff
     mutex_lock --> may sleep

fcoe_ctlr_vn_disc
   fc_rport_login
     mutex_lock --> may sleep

fcoe_ctlr_vn_age
   fc_rport_logoff
     mutex_lock --> may sleep

These bugs are found by my static analysis tool and my code review.

Thanks,
Jia-Ju Bai

Re: [BUG] scsi/fcoe: Sleep-in-atomic bugs in fcoe driver

[Johannes Thumshirn]

On Tue, Oct 03, 2017 at 11:02:33AM +0800, Jia-Ju Bai wrote:
> According to fcoe_ctlr.c, the driver may sleep under a RCU lock,
> and the function call paths are:
> fcoe_ctlr_disc_stop_locked (acquire the RCU lock)
>   fc_rport_logoff
>     mutex_lock --> may sleep
> 
> fcoe_ctlr_vn_disc
>   fc_rport_login
>     mutex_lock --> may sleep
> 
> fcoe_ctlr_vn_age
>   fc_rport_logoff
>     mutex_lock --> may sleep
> 
> These bugs are found by my static analysis tool and my code review.
> 
> Thanks,
> Jia-Ju Bai
> 

Thanks for the report, coincidentally I have a bug report for this as well (in
a real setup not just static analysis) and gave the reporter a patch to test.
Once it's verified I'll post it here.

Thanks,
	Johannes

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Johannes Thumshirn                                          Storage
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