citrix_ica - "wfica" generates deadlock in linux_sys_futex...

[Konstantin Belousov]

On Tue, Mar 08, 2016 at 12:30:10PM +0300, Chagin Dmitry wrote:
> On Tue, Mar 08, 2016 at 10:03:50AM +0100, Nils Beyer wrote:
> > Chagin Dmitry wrote:
> > >>>> using 10.3-RC1 (r296451M) "wfica" from citrix_ica generates a deadlock
> > >>>> in linux_sys_futex:
> > >>>> ==============================================================================
> > >>>> #tail -50 ktrace.wfica.log
> > >>>
> > >>> nice, please, do kdump -HAR -m256 > xxx.log and place a whole log
> > >>> somewhere
> > >> 
> > >> done:
> > >> 
> > >>     http://www.renzel.net/_upload_/ktrace.wfica.log
> > >
> > > thanks, do u have same log but for working wfica?
> > 
> > here (kernel from 10.2-RELEASE):
> > 
> >     http://www.renzel.net/_upload_/ktrace.wfica.working.log.gz
> >
> so, my assumptions confirmed, in kernel from 10.2:
> 
>   1649 100695 wfica    0.000042 CALL  L32  linux_ipc(0x2,0x1e240,0x1,0x7b6,0,0x2d4ca598)
>   1649 100695 wfica    0.000010 RET   L32  linux_ipc  65536/0x10000
> 						^^^^^ succeded
> 
>   1649 100695 wfica    0.000007 CALL  L32  linux_ipc(0x3,0x10000,0,0x111,0x2d4ca588,0x2d4ca598)
>   1649 100695 wfica    0.000008 RET   L32  linux_ipc  0
> 
> 
> 
> in new kernel:
> 
>   1828 100750 wfica    0.000031 CALL  L32  linux_ipc(0x2,0x1e240,0x1,0x7b6,0,0x2d4cb598)
>   1828 100750 wfica    0.000010 RET   L32  linux_ipc  -1 errno 17 File exists
>   1828 100750 wfica    0.000008 CALL  L32  linux_ipc(0x2,0x1e240,0x1,0x1b6,0,0x2d4cb598)
>   1828 100750 wfica    0.000007 RET   L32  linux_ipc  65536/0x10000
> 
> this is strange as no ipc changes are made in stable/10

There was one interesting change, AFAIR.

Check the value of sysctl kern.ipc.shm_allow_removed, and if it's value
is one, change it to zero.