Chirag, Kindly understand what xavier is trying to do. He is Trying to disable smp. The RT - Linux Code is dependent on the mutex lock to perform some soft/hard real time processing. This is an problem with the mutex lock. Kindly check with some one before signing off patches. Thanks, Sujit On 9/8/08, Chirag Jog <chirag@xxxxxxxxxxxxxxxxxx> wrote: > * xavier droubay <xavier.droubay@xxxxxxxxx> [2008-09-08 03:06:51]: > > > Hello, > > > > I experienced this "rtmutex.c:743" known bug with rt3 patch, using > > > > http://www.kernel.org/pub/linux/kernel/v2.6/linux-2.6.26.3.tar.bz2 > > http://rt.et.redhat.com/download/patch-2.6.26.3-rt3.bz2 > > > > I compiled this kernel with the "make-kpkg" debian utility. > > > > I first compiled this kernel with NO SMP, NO HIGHMEM, and partial ACPI > > (without fan, processor, ... modules). Attached file > > "config-2.6.26.3-rt3lowlty.frwr.gz". > > I didn't experience any problem with this kernel. > > > > I then enabled SMP and HIGHMEM, and experienced "rtmutex.c:743" BUG. > > Attached files > > "config-2.6.26.3-rt3rt-smp-hm.gz" and "dmesg.gz" for some BUGGY message. > > > > > > I have seen somewhere on the archive, that some people still > > experienced problems with SMP. > > I guess no fix has been done from rt3 to rt7 patch. Can you confirm? > > > > If so, which recent kernel should I use in order to get smp and rt > > running without problems? > > > This simple patch should solve the above problem. Seeing the config, its > seems to be a 32bit box. > > > It convert tlbstate_lock spin_lock to raw_spin_lock. > Preemption has already been disabled, hence this change shouldn't > affect latency numbers. > > > Signed-Off-By: Chirag <chirag@xxxxxxxxxxxxxxxxxx> > > > diff --git a/arch/x86/kernel/tlb_32.c b/arch/x86/kernel/tlb_32.c > index 9bb2363..228849c 100644 > --- a/arch/x86/kernel/tlb_32.c > +++ b/arch/x86/kernel/tlb_32.c > @@ -23,7 +23,7 @@ DEFINE_PER_CPU(struct tlb_state, cpu_tlbstate) > static cpumask_t flush_cpumask; > static struct mm_struct *flush_mm; > static unsigned long flush_va; > -static DEFINE_SPINLOCK(tlbstate_lock); > +static DEFINE_RAW_SPINLOCK(tlbstate_lock); > > /* > * We cannot call mmdrop() because we are in interrupt context, > > > > -- > 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 > -- --linux(2.4/2.6),bsd(4.5.x+),solaris(2.5+) -- 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
