On Thu, Apr 5, 2012 at 6:06 AM, Milton Miller <miltonm@xxxxxxx> wrote: > > On Wed, 4 Apr 2012 about 22:12:36 +0200, Sasha Levin wrote: >> I've starting seeing soft lockups resulting from smp_call_function() >> calls. I've attached two different backtraces of this happening with >> different code paths. >> >> This is running inside a KVM guest with the trinity fuzzer, using >> today's linux-next kernel. > > Hi Sasha. > > You have two different call sites (arch/x86/mm/pageattr.c > cpa_flush_range and net/core/dev.c netdev_run_todo), and both use > call on_each_cpu with wait=1. > > I tried a few options but can't get close enough to your compiled > length of 2a0 to know if the code is spinning on the first > csd_lock_wait in csd_lock or in the second csd_lock_wait after the > call to arch_send_call_function_ipi_mask (aka smp_ops + 0x44 in my > x86_64 compile). Please check your disassembly and report. Hi Milton, # addr2line -i -e /usr/src/linux/vmlinux ffffffff8111f30e /usr/src/linux/kernel/smp.c:102 /usr/src/linux/kernel/smp.c:554 So It's the 2nd lock. I'll work on adding the debug code mentioned in your mail. -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
