Re: general protection fault, probably for non-canonical address in nfsd

[Hans-Peter Jansen <hpj@urpla.net>]

Am Montag, 8. Juni 2020, 17:28:53 CEST schrieb Chuck Lever:
> > On Jun 7, 2020, at 1:44 PM, Hans-Peter Jansen <hpj@urpla.net> wrote:
> > 
> > Am Sonntag, 7. Juni 2020, 18:01:55 CEST schrieb Anthony Joseph Messina:
> >> On Sunday, June 7, 2020 10:32:44 AM CDT Hans-Peter Jansen wrote:
> >>> Hi,
> >>> 
> >>> after upgrading the kernel from 5.6.11 to 5.6.14, we suffer from regular
> >>> crashes of nfsd here:
> >>> 
> >>> 2020-06-07T01:32:43.600306+02:00 server rpc.mountd[2664]: authenticated
> >>> mount request from 192.168.3.16:303 for /work (/work)
> >>> 2020-06-07T01:32:43.602594+02:00 server rpc.mountd[2664]: authenticated
> >>> mount request from 192.168.3.16:304 for /work/vmware (/work)
> >>> 2020-06-07T01:32:43.602971+02:00 server rpc.mountd[2664]: authenticated
> >>> mount request from 192.168.3.16:305 for /work/vSphere (/work)
> >>> 2020-06-07T01:32:43.606276+02:00 server kernel: [51901.089211] general
> >>> protection fault, probably for non-canonical address 0xb9159d506ba40000:
> >>> 0000 [#1] SMP PTI 2020-06-07T01:32:43.606284+02:00 server kernel:
> >>> [51901.089226] CPU: 1 PID: 3190 Comm: nfsd Tainted: G           O
> >>> 5.6.14-lp151.2-default #1 openSUSE Tumbleweed (unreleased)
> >>> 2020-06-07T01:32:43.606286+02:00 server kernel: [51901.089234] Hardware
> >>> name: System manufacturer System Product Name/P7F-E, BIOS 0906
> >> 
> >> I see similar issues in Fedora kernels 5.6.14 through 5.6.16
> >> https://bugzilla.redhat.com/show_bug.cgi?id=1839287
> >> 
> >> On the client I mount /home with sec=krb5p, and /mnt/koji with sec=krb5
> > 
> > Thanks for confirmation.
> > 
> > Apart from the hassle with server reboots, this issue has some DOS
> > potential, I'm afraid.
> 
> If you have a reproducer (even a partial one) then bisecting between a
> known good kernel and v5.6.14 (or 16) would be helpful.

I would love to bisect, but this is my primary production machine, that needs 
to be up as much as possible. Apart from that, I'm about to leave the site for 
a week and been severely time constrained for the next couple of weeks..

Sorry. 

Anthony?
--
Pete