Re: Regression: SUNRPC: Use poll() to fix up the socket requeue races

[Tony Lindgren <tony@atomide.com>]

Hi,

* Trond Myklebust <trondmy@hammerspace.com> [700101 00:00]:
> On Mon, 2019-02-25 at 22:27 +0000, Jon Hunter wrote:
> > On 25/02/2019 21:03, Trond Myklebust wrote:
> > This is nfsroot. I don't specify any particular NFS version from 
> > the kernel cmdline, but this is seen with ARM kernel configs
> > tegra_defconfig and multi_v7_defconfig. 
> > 
> > Looking at the logs I am seeing the following crash which appears
> > to point to UDP ...
> > 
> > [    8.032956] Unable to handle kernel NULL pointer dereference at
> > virtual address 00000024
> > [    8.041137] pgd = (ptrval)
> > [    8.043858] [00000024] *pgd=00000000
> > [    8.047437] Internal error: Oops: 5 [#1] SMP ARM
> > [    8.052049] Modules linked in:
> > [    8.055104] CPU: 1 PID: 100 Comm: kworker/u9:2 Not tainted 5.0.0-
> > rc7-next-20190222-g94a4752 #1
> > [    8.063699] Hardware name: NVIDIA Tegra SoC (Flattened Device
> > Tree)
> > [    8.069960] Workqueue: xprtiod xs_udp_data_receive_workfn
> > [    8.075353] PC is at udp_poll+0x30/0x64
> > [    8.079178] LR is at udp_poll+0x10/0x64
> 
> Thanks! I see what the issue is now and I'll be fixing it ASAP.

I'm seeing this also with NFSroot. I can test the fix when available,
that is if you can please Cc me on the fix.

Thanks,

Tony