On 06/20/2018 10:27 AM, Boris Ostrovsky wrote: > On 06/20/2018 02:17 AM, Juergen Gross wrote: >> On 20/06/18 05:31, Boris Ostrovsky wrote: >>> On 06/19/2018 05:30 PM, Brian Woods wrote: >>>> I'm currently seeing an issue where when booting from a recent Linux >>>> kernel without nospec_store_bypass_disable. There's a NULL pointer >>>> having to do with a lock. I put some printks in and it seems that in >>>> arch/x86/kernel/process.c >>>> that speculative_store_bypass_ht_init isn't getting called which >>>> initializes the spin lock. >>> >>> speculative_store_bypass_ht_init() is not called on PV. For BSP it is >>> called from native_smp_prepare_cpus() and for APs it is called from >>> start_secondary(), neither of which is in PV code path. >>> >>> I think the most logical place to put it is in cpu_init(). >> I don't think so. speculative_store_bypass_ht_init() requires >> topology_sibling_cpumask to be setup which happens only after the call >> of cpu_init(). > Right. > >> We should add the call to cpu_bringup() in smp_pv.c > That still leaves cpu0 uninitialized. xen_pv_smp_prepare_cpus() may need > this call as well if we are to follow barmetal example.
Oh, and I see now that you posted a patch that does just that. -boris > > I also wonder whether this works at all for !SMP. > > -boris > > _______________________________________________ > Xen-devel mailing list > Xen-devel@lists.xenproject.org > https://lists.xenproject.org/mailman/listinfo/xen-devel _______________________________________________ Xen-devel mailing list Xen-devel@lists.xenproject.org https://lists.xenproject.org/mailman/listinfo/xen-devel