Re: [Linuxptp-users] [E1000-devel] Need help with igb driver suspend crash issue

[Keller, J. E <jac...@in...>]

Hi,

> -----Original Message-----
> From: vidya sagar [mailto:sag...@gm...]
> Sent: Wednesday, May 11, 2016 3:25 AM
> To: e10...@li...; linuxptp-
> us...@li...
> Subject: Re: [E1000-devel] Need help with igb driver suspend crash issue
> 
> <<< Including lin...@li... >>>
> 
> On Wed, May 11, 2016 at 3:51 PM, vidya sagar <sag...@gm...>
> wrote:
> 
> > Hi,
> > I'm using Intel IGB I350 NIC card on one of our arm based platforms.
> > While suspending the system, sometimes we see "igb 0000:01:00.0 eth1:
> PCIe
> > link lost, device now detached" print in the log and subsequent resume
> > causes system to crash. After digging the code (BTW, I'm using kernel-3.18
> > release), it looks like the above print comes because of the following call
> > flow, which got executed after igb_suspend() is called ( I confirmed this
> > with the help of prints)
> >
> > [10846.434381] [<ffffffc000089ce4>] dump_backtrace+0x0/0xf8
> > [10846.434386] [<ffffffc000089ea0>] show_stack+0x10/0x1c
> > [10846.434393] [<ffffffc000bc3b70>] dump_stack+0x80/0xc4
> > [10846.434397] [<ffffffc000613d3c>] igb_rd32+0xb0/0x1a8
> > [10846.434400] [<ffffffc00062eb0c>] igb_ptp_read_82580+0x18/0x48
> > [10846.434407] [<ffffffc000106e6c>] timecounter_read+0x1c/0x60
> > [10846.434410] [<ffffffc00062f338>] igb_ptp_gettime_82576+0x2c/0x88
> > [10846.434413] [<ffffffc00062f41c>] igb_ptp_overflow_check+0x1c/0x58
> > [10846.434419] [<ffffffc0000ba584>] process_one_work+0x154/0x414
> > [10846.434424] [<ffffffc0000bb338>] worker_thread+0x13c/0x4e4
> > [10846.434428] [<ffffffc0000bfc4c>] kthread+0xf8/0x110
> >
> > It looks like reading timer registers would have returned all F's as the
> > device is already in D3Hot state.
> > Is my understanding correct. Is there any patch available to fix this
> > issue?
> > Let me know if more information is needed.
> >

Maybe an ordering bug when doing suspend that we try to read things too late. Is that stack trace the actual crash or did you add the dump_stack yourself?

Thanks,
Jake

> > Thanks,
> > Vidya Sagar
> >