On Sat, Aug 18, 2018 at 2:50 PM Thomas Gleixner <tglx@xxxxxxxxxxxxx> wrote: > > On Fri, 17 Aug 2018, Greg Kroah-Hartman wrote: > > On Fri, Aug 17, 2018 at 02:39:00PM +0200, Jinpu Wang wrote: > > > > > > I found the problem, CONFIG_HOTPLUG_SMT is enable due to CONFIG_SMP, > > > but I did explicitly enable CONFIG_HOTPLUG_CPU. > > > > > > That's why the smt dir is missing, and kernel panic when I boot with > > > 'nosmt' or 'l1tf=full' probably also other combination. > > > > > > With CONFIG_HOTPLUG_CPU=y, it works fine so far. > > > > So do we need a new configuration dependancy here to resolve this > > problem? Why is this not an issue in Linus's tree? > > That's probably the same problem on Linus tree. Have not tested it yet > though. I'll have a look. > > Thanks, > > tglx > Yeah, it's the same problem on Linus tree. Probably makes sense to do the following, I can sent a formal patch if you think it's right thing to do: diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index b0312f8..8a52f0b 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -188,7 +188,7 @@ config X86 select HAVE_SYSCALL_TRACEPOINTS select HAVE_UNSTABLE_SCHED_CLOCK select HAVE_USER_RETURN_NOTIFIER - select HOTPLUG_SMT if SMP + select HOTPLUG_SMT if SMP && HOTPLUG_CPU select IRQ_FORCED_THREADING select NEED_SG_DMA_LENGTH select PCI_LOCKLESS_CONFIG -- Jack Wang Linux Kernel Developer ProfitBricks GmbH Greifswalder Str. 207 D - 10405 Berlin Tel: +49 30 577 008 042 Fax: +49 30 577 008 299 Email: jinpu.wang@xxxxxxxxxxxxxxxx URL: https://www.profitbricks.de Sitz der Gesellschaft: Berlin Registergericht: Amtsgericht Charlottenburg, HRB 125506 B Geschäftsführer: Achim Weiss, Matthias Steinberg, Christoph Steffens