On Fri, 2 Sep 2005, Alexander Nyberg wrote: > On Thu, Sep 01, 2005 at 03:55:42AM -0700 Andrew Morton wrote: > > > > > ftp://ftp.kernel.org/pub/linux/kernel/people/akpm/patches/2.6/2.6.13/2.6.13-mm1/ > > > > i386-boottime-for_each_cpu-broken.patch > i386-boottime-for_each_cpu-broken-fix.patch > > The SMP version of __alloc_percpu checks the cpu_possible_map > before allocating memory for a certain cpu. With the above patches > the BSP cpuid is never set in cpu_possible_map which breaks CONFIG_SMP > on uniprocessor machines (as soon as someone tries to dereference > something allocated via __alloc_percpu, which in fact is never allocated > since the cpu is not set in cpu_possible_map).
Yes indeed, if there is no mptable or madt we would have missed setting it. > The below fixes this, I'm not entirely sure about the voyager > part, should the cpu_possible_map really be CPU_MASK_ALL to begin > with there, Zwane? I wanted to avoid breaking it wholesale and since i don't entirely understand the voyager SMP boot sequence, i opted for the safe method. cpu_possible_map is fine because it's supposed to cover all possible processors, upto NR_CPUS. > Signed-off-by: Alexander Nyberg <[EMAIL PROTECTED]> Thanks Alex, Acked-by: Zwane Mwaikambo <[EMAIL PROTECTED]> > Index: mm/arch/i386/kernel/smpboot.c > =================================================================== > --- mm.orig/arch/i386/kernel/smpboot.c 2005-09-02 15:28:20.000000000 > +0200 > +++ mm/arch/i386/kernel/smpboot.c 2005-09-02 16:16:46.000000000 +0200 > @@ -1265,6 +1265,7 @@ > cpu_set(smp_processor_id(), cpu_online_map); > cpu_set(smp_processor_id(), cpu_callout_map); > cpu_set(smp_processor_id(), cpu_present_map); > + cpu_set(smp_processor_id(), cpu_possible_map); > per_cpu(cpu_state, smp_processor_id()) = CPU_ONLINE; > } > > Index: mm/arch/i386/mach-voyager/voyager_smp.c > =================================================================== > --- mm.orig/arch/i386/mach-voyager/voyager_smp.c 2005-09-02 > 15:28:20.000000000 +0200 > +++ mm/arch/i386/mach-voyager/voyager_smp.c 2005-09-02 16:17:29.000000000 > +0200 > @@ -1910,6 +1910,7 @@ > { > cpu_set(smp_processor_id(), cpu_online_map); > cpu_set(smp_processor_id(), cpu_callout_map); > + cpu_set(smp_processor_id(), cpu_possible_map); > } > > int __devinit > - > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > the body of a message to [EMAIL PROTECTED] > More majordomo info at http://vger.kernel.org/majordomo-info.html > Please read the FAQ at http://www.tux.org/lkml/ > - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/