* Ingo Molnar <mingo@xxxxxxx> wrote: > hardirq_count() is correct, but looking at PF_HARDIRQ's definition in sched.h: > > #define PF_EXITPIDONE 0x00000008 /* pi exit done on shut down */ > #define PF_VCPU 0x00000010 /* I'm a virtual CPU */ > #define PF_HARDIRQ 0x08000020 /* hardirq context */ > #define PF_NOSCHED 0x00000020 /* Userspace does not expect scheduling */ > #define PF_FORKNOEXEC 0x00000040 /* forked but didn't exec */ > > Reveals that due to a typo it not only overlaps the PF_NOSCHED bit, but > also has a spurious 0x08000000 component. The reason is that when we forward ported the definition, i first moved it to the 0x08000000 slot - but that slot was already taken. (our PF_ task flag space is really crowded ...) Then i moved it to a free spot, 0x20. Or so i thought: a later -rt patch in the queue introduced PF_NOSCHED which overlapped it. But the bigger problem was the spurious 0x08000000 component, which overlaps with: #define PF_SOFTIRQ 0x08000000 /* softirq context */ Explaining why the warning triggered in ksoftirqd ;-) Anyway, my fix should solve this. Do you still see the lockup under X? (make sure you also have the IPI fix applied, see the patch in this same thread.) Ingo -- To unsubscribe from this list: send the line "unsubscribe linux-rt-users" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
