On Thu, 9 Apr 2020 at 17:10, Qian Cai <cai@xxxxxx> wrote: > > > > > On Apr 9, 2020, at 3:03 AM, Marco Elver <elver@xxxxxxxxxx> wrote: > > > > On Wed, 8 Apr 2020 at 23:29, Qian Cai <cai@xxxxxx> wrote: > >> > >> > >> > >>> On Apr 8, 2020, at 5:25 PM, Paolo Bonzini <pbonzini@xxxxxxxxxx> wrote: > >>> > >>> On 08/04/20 22:59, Qian Cai wrote: > >>>> Running a simple thing on this AMD host would trigger a reset right away. > >>>> Unselect KCSAN kconfig makes everything work fine (the host would also > >>>> reset If only "echo off > /sys/kernel/debug/kcsan” before running qemu-kvm). > >>> > >>> Is this a regression or something you've just started to play with? (If > >>> anything, the assembly language conversion of the AMD world switch that > >>> is in linux-next could have reduced the likelihood of such a failure, > >>> not increased it). > >> > >> I don’t remember I had tried this combination before, so don’t know if it is a > >> regression or not. > > > > What happens with KASAN? My guess is that, since it also happens with > > "off", something that should not be instrumented is being > > instrumented. > > No, KASAN + KVM works fine. > > > > > What happens if you put a 'KCSAN_SANITIZE := n' into > > arch/x86/kvm/Makefile? Since it's hard for me to reproduce on this > > Yes, that works, but this below alone does not work, > > KCSAN_SANITIZE_kvm-amd.o := n There are some other files as well, that you could try until you hit the right one. But since this is in arch, 'KCSAN_SANITIZE := n' wouldn't be too bad for now. If you can't narrow it down further, do you want to send a patch? Thanks, -- Marco > I have been able to reproduce this on a few AMD hosts. > > > exact system, I'd ask you to narrow it down by placing 'KCSAN_SANITIZE > > := n' into suspect subsystems' Makefiles. Once you get it to work with > > that, we can refine the solution. > > > > Thanks, > > -- Marco >
