Re: PROBLEM: NULL pointer dereference in kernel 4.14.6

2017-12-20 Thread Bronek Kozicki
On Wed, 20 Dec 2017, at 3:14 PM, Tejun Heo wrote: > On Tue, Dec 19, 2017 at 05:42:39AM -0800, Tejun Heo wrote: > > On Sun, Dec 17, 2017 at 03:24:48PM -0800, vcap...@pengaru.com wrote: > > > On Sun, Dec 17, 2017 at 05:49:44PM +, Bronek Kozicki wrote: > > > > I just upgraded to 4.14.7 and tried t

Re: PROBLEM: NULL pointer dereference in kernel 4.14.6

2017-12-20 Thread Tejun Heo
On Tue, Dec 19, 2017 at 05:42:39AM -0800, Tejun Heo wrote: > On Sun, Dec 17, 2017 at 03:24:48PM -0800, vcap...@pengaru.com wrote: > > On Sun, Dec 17, 2017 at 05:49:44PM +, Bronek Kozicki wrote: > > > I just upgraded to 4.14.7 and tried to reproduce this error, this time > > > under strace. As

Re: PROBLEM: NULL pointer dereference in kernel 4.14.6

2017-12-19 Thread Tejun Heo
Hello, On Mon, Dec 18, 2017 at 03:17:54PM -0500, George Amanakis wrote: > I can replicate this on a Thinkpad X230i running archlinux with latest > 4.14.7 kernel, without the ZFS modules. > > Steps to reproduce: > 1) create a virtual machine using libvirt (attached xml) > 2) virsh start vm > 3) he

Re: PROBLEM: NULL pointer dereference in kernel 4.14.6

2017-12-19 Thread Tejun Heo
On Sun, Dec 17, 2017 at 03:24:48PM -0800, vcap...@pengaru.com wrote: > On Sun, Dec 17, 2017 at 05:49:44PM +, Bronek Kozicki wrote: > > I just upgraded to 4.14.7 and tried to reproduce this error, this time > > under strace. As you can see this happens when systemctl tries to read a > > specif

Re: PROBLEM: NULL pointer dereference in kernel 4.14.6

2017-12-18 Thread George Amanakis
I can replicate this on a Thinkpad X230i running archlinux with latest 4.14.7 kernel, without the ZFS modules. Steps to reproduce: 1) create a virtual machine using libvirt (attached xml) 2) virsh start vm 3) head /sys/fs/cgroup/unified/machine.slice/machine- qemu\\x2d2\\x2dvm.scope/cgroup.procs

Re: PROBLEM: NULL pointer dereference in kernel 4.14.6

2017-12-18 Thread Bronek Kozicki
On 17/12/2017 23:24, vcap...@pengaru.com wrote: On Sun, Dec 17, 2017 at 05:49:44PM +, Bronek Kozicki wrote: I just upgraded to 4.14.7 and tried to reproduce this error, this time under strace. As you can see this happens when systemctl tries to read a specific entry under /sys/fs . In case

Re: PROBLEM: NULL pointer dereference in kernel 4.14.6

2017-12-17 Thread vcaputo
On Sun, Dec 17, 2017 at 05:49:44PM +, Bronek Kozicki wrote: > I just upgraded to 4.14.7 and tried to reproduce this error, this time under > strace. As you can see this happens when systemctl tries to read a specific > entry under /sys/fs . In case this matters, the entry is for a small virtu

Re: PROBLEM: NULL pointer dereference in kernel 4.14.6

2017-12-17 Thread Bronek Kozicki
FWIW, I can do "cat" . I get a single number seemingly followed by an infinite stream of 0s (I tried wc -l, but did not want to wait very long and killed it). Here is what it looks like, if limited by "head": root@gdansk ~ # cat '/sys/fs/cgroup/unified/machine.slice/machine-qemu\x2d1\x2dkartuzy\x2

Re: PROBLEM: NULL pointer dereference in kernel 4.14.6

2017-12-17 Thread Randy Dunlap
On 12/17/2017 10:30 AM, Bronek Kozicki wrote: > On 17/12/2017 18:25, Randy Dunlap wrote: >> On 12/17/2017 09:49 AM, Bronek Kozicki wrote: >>> I just upgraded to 4.14.7 and tried to reproduce this error, this time >>> under strace. As you can see this happens when systemctl tries to read a >>> spe

Re: PROBLEM: NULL pointer dereference in kernel 4.14.6

2017-12-17 Thread Bronek Kozicki
On 17/12/2017 18:25, Randy Dunlap wrote: On 12/17/2017 09:49 AM, Bronek Kozicki wrote: I just upgraded to 4.14.7 and tried to reproduce this error, this time under strace. As you can see this happens when systemctl tries to read a specific entry under /sys/fs . In case this matters, the entry

Re: PROBLEM: NULL pointer dereference in kernel 4.14.6

2017-12-17 Thread Randy Dunlap
On 12/17/2017 09:49 AM, Bronek Kozicki wrote: > I just upgraded to 4.14.7 and tried to reproduce this error, this time under > strace. As you can see this happens when systemctl tries to read a specific > entry under /sys/fs . In case this matters, the entry is for a small virtual > machine runn

Re: PROBLEM: NULL pointer dereference in kernel 4.14.6

2017-12-17 Thread Bronek Kozicki
I just upgraded to 4.14.7 and tried to reproduce this error, this time under strace. As you can see this happens when systemctl tries to read a specific entry under /sys/fs . In case this matters, the entry is for a small virtual machine running under qemu/kvm and managed by libvirt. open("/sy

Re: PROBLEM: NULL pointer dereference in kernel 4.14.6

2017-12-17 Thread Bronek Kozicki
This has happend again, and hopefully the report is not as mangled as the previous one. I was also trying to start "systemctl status", only once this time. The kernel build is different because I've just disabled RCU tracing/debugging options. One more thing, this kernel was built with gcc 7.2.1