2011/4/30 Philippe Gerum <[email protected]>: > On Fri, 2011-04-29 at 18:08 +0200, Jean-Michel Hautbois wrote: >> 2011/4/29 Philippe Gerum <[email protected]>: >> > On Thu, 2011-04-28 at 10:33 +0200, Jean-Michel Hautbois wrote: >> >> 2011/4/27 Philippe Gerum <[email protected]>: >> >> > On Wed, 2011-04-27 at 20:42 +0200, Jean-Michel Hautbois wrote: >> >> >> Hi list, >> >> >> >> >> >> I am currently using a Xenomai port on a linux 2.6.35.11 linux kernel >> >> >> and the adeos-ipipe-2.6.35.7-powerpc-2.12-01.patch. >> >> >> I am facing a scheduling issue on a P2020 (dual core PowerPC), and I >> >> >> get the following message : >> >> >> >> >> >> Badness at arch/powerpc/mm/mmu_context_nohash.c:209 >> >> >> NIP: c0018d20 LR: c039b94c CTR: c00343e4 >> >> >> REGS: ecfadce0 TRAP: 0700 Tainted: G W (2.6.35.11) >> >> >> MSR: 00021000 <ME,CE> CR: 24000488 XER: 00000000 >> >> >> TASK = ec5220d0[496] 'sipaq' THREAD: ecfac000 CPU: 1 >> >> >> GPR00: 00000001 ecfadd90 ec5220d0 ec5df340 ec58a700 00000000 ffffffff >> >> >> 00000003 >> >> >> GPR08: c04a2d98 00000007 c04a2d98 0067e000 0002f385 1007f1f8 c04a5b40 >> >> >> ecfac040 >> >> >> GPR16: c04a5b40 c04deb80 c04a2120 c04a2d98 c04a5b40 c04d008c ecfac000 >> >> >> 00029000 >> >> >> GPR24: c04d0000 c04d1e6c 00000001 ec58a700 eceaf390 c04d1e78 c0b23b40 >> >> >> ec5df340 >> >> >> NIP [c0018d20] switch_mmu_context+0x80/0x438 >> >> >> LR [c039b94c] schedule+0x774/0x7dc >> >> >> Call Trace: >> >> >> [ecfadd90] [44000484] 0x44000484 (unreliable) >> >> >> [ecfadde0] [c039b94c] schedule+0x774/0x7dc >> >> >> [ecfade50] [c039cb98] do_nanosleep+0xc8/0x114 >> >> >> [ecfade80] [c0059bf8] hrtimer_nanosleep+0xd8/0x158 >> >> >> [ecfadf10] [c0059d48] sys_nanosleep+0xd0/0xd4 >> >> >> [ecfadf40] [c0013c0c] ret_from_syscall+0x0/0x3c >> >> >> --- Exception: c01 at 0xffa6cc4 >> >> >> LR = 0xffa6cb0 >> >> >> Instruction dump: >> >> >> 40a2fff0 4c00012c 2f800000 409e0128 813b018c 2f830000 39290001 913b018c >> >> >> 419e0020 8003018c 7c000034 5400d97e <0f000000> 8123018c 3929ffff >> >> >> 9123018c >> >> >> >> >> >> Do you have a clue on how to start debugging it ? >> >> > >> >> > Yes, but that can't be easily summarized here. In short, we have a >> >> > serious problem with the sharing of the MMU context between the Linux >> >> > and Xenomai schedulers in the SMP case on powerpc. >> >> >> >> OK, good to know that it is a known issue. If there is a thread with >> >> some thoughts about it, I am interested ;). >> >> >> >> >> It is happening quite randomly... :). >> >> > >> >> > Does disabling CONFIG_XENO_HW_UNLOCKED_SWITCH clear this issue? >> >> > >> >> >> >> Well, yes and no. It starts well, but when booting the kernel I get : >> > >> > >> > The mm switch issue was specifically addressed by this patch, which is >> > part of 2.12-01: >> > http://git.denx.de/?p=ipipe-2.6.git;a=commit;h=c14a47630d62d0328de1957636dceb1d498f7048 >> > >> > However, it the last 2.6.35 patch issued was based on 2.6.35.7, not >> > 2.6.35.11, so there is still the possibility that something went wrong >> > while you forward ported this code. >> > >> > - Please check that mmu_context_nohash.c does contain the fix above as >> > it should >> >> It is ok, I have the fix. > > Does 2.6.35.7-2.12-02 exhibit the issue as well?
It doesn't seem to exhibit the issue... I didn't try during a long time though... >> >> > - Please try Richard's suggestion, i.e. moving to 2.6.36, which may give >> > us more hints. >> >> It is better. I don't have the badness on mmu context anymore. >> This gives some hints ;). >> > > Yes and no. The mmu management code involved was untouched between > 2.6.35 and 2.6.36, so I still don't get why this activity counter gets > trashed yet. > >> >> Badness at kernel/lockdep.c:2327 >> >> NIP: c006e554 LR: c006e53c CTR: 000186a0 >> > >> > Adeos sometimes conflicts with the vanilla IRQ state tracer. I'll have a >> > look at this. Disable CONFIG_TRACE_IRQFLAGS. >> >> Yes, but I *want* to have the CONFIG_TRACE_IRQFLAGS on. I just wanted >> to tell that I had the problem, in order to be sure it is known ;). >> > > Sure, but one issue at a time. > >> JM > > -- > Philippe. > > > _______________________________________________ Xenomai-core mailing list [email protected] https://mail.gna.org/listinfo/xenomai-core
