On Mon, 2019-02-25 at 22:27 +0000, Jon Hunter wrote: > On 25/02/2019 21:03, Trond Myklebust wrote: > > On Mon, 2019-02-25 at 20:25 +0000, Jon Hunter wrote: > > > Hi Trond, > > > > > > Starting in next-20190222 I have observed a regression with NFS > > > causing > > > some of our boards to fail to boot. Bisect points to your commit > > > ... > > > > > > commit 0ffe86f48026b7f34db22d1004bc9992f0db8b33 > > > Author: Trond Myklebust <trond.myklebust@xxxxxxxxxxxxxxx> > > > Date: Wed Jan 30 14:51:26 2019 -0500 > > > > > > SUNRPC: Use poll() to fix up the socket requeue races > > > > > > > > > After reverting this on top of -next I no longer see the problem. > > > I > > > have > > > not had chance to look any closer, but wanted to see if you had > > > any > > > ideas what might be the problem. > > > > > > Cheers > > > Jon > > > > What kind of boot is this? UDP or TCP? nfsroot? NFSv3 or NFSv4? > > 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. Cheers Trond -- Trond Myklebust Linux NFS client maintainer, Hammerspace trond.myklebust@xxxxxxxxxxxxxxx