I might have found what is causing this problem : CONFIG_CPU_SPECTRE It was the noticeable difference between my last (4.4.189) kernel release not showing this problem, and the next I tried (4.4.227). If I modify the Kconfig to disable CPU_SPECTRE, the problem does not show up anymore.
I'll dig a little deeper into that now. François Le Mercredi, Septembre 30, 2020 08:42 CEST, François Legal <[email protected]> a écrit: > So I decided to dig a little deeper in this problem, and found out that it is > not xenomai3.1 specific. > I tried with xenomai-3.0.9 and linux 4.4.227 -> same problem. > I thought it might be a matter of ipipe patch not quite fit to 4.4.227, so I > decided to try with latest ipipe-4.4.y-cip from git and xenomai 3.0.9, but > the same problem happens. > > François > > Le Vendredi, Septembre 25, 2020 18:11 CEST, François Legal via Xenomai > <[email protected]> a écrit: > > > Sorry to come back so late on that topic. > > I took some time to write a simple test program, which is attached. > > > > Config is as follows : > > xenomai-3.1 > > linux-4.4.227 > > > > François > > > > Le Vendredi, Août 21, 2020 20:04 CEST, Jan Kiszka <[email protected]> > > a écrit: > > > > > On 20.08.20 15:46, François Legal via Xenomai wrote: > > > > Using RTNet with multiple interfaces, xenomai 3.1 with linux 4.4 > > > > Whenever a posix RT thread calls recvmsg (), I get this error. > > > > > > > > I could track this down to line 422 in udp.c : msg = > > > > rtnet_get_arg(fd, &_msg, u_msg, sizeof(_msg)); > > > > > > > > If I disassemble the kernel, the failing instruction (at 0x80272444) is > > > > a nop in arm_copy_from_user > > > > Am I doing anything wrong ? > > > > > > Maybe you are passing an invalid pointer to recvmsg, directly or in its > > > message structures. That would cause an exception which is fixed up but > > > also reported. Do you get an error in return? > > > > > > Jan > > > > > > -- > > > Siemens AG, Corporate Technology, CT RDA IOT SES-DE > > > Corporate Competence Center Embedded Linux > > -------------- next part -------------- > > A non-text attachment was scrubbed... > > Name: test-net.c > > Type: application/octet-stream > > Size: 6141 bytes > > Desc: not available > > URL: > > <http://xenomai.org/pipermail/xenomai/attachments/20200925/f745e32f/attachment.obj> >
