On Wed, Jul 13, 2022 at 11:11 PM Sean Christopherson <seanjc@xxxxxxxxxx> wrote: > > On Wed, Jul 13, 2022, Jinpu Wang wrote: > > On Wed, Jul 13, 2022 at 3:01 PM Greg Kroah-Hartman > > <gregkh@xxxxxxxxxxxxxxxxxxx> wrote: > > > > > > On Wed, Jul 13, 2022 at 02:26:44PM +0200, Jinpu Wang wrote: > > > > On Wed, Jul 13, 2022 at 12:49 PM Jinpu Wang <jinpu.wang@xxxxxxxxx> wrote: > > > > > #5.10.131-1+feature+linux+5.10.y+20220712.1850+30f4172c~deb11 > > ... > > > > > > [ 1895.979325] Call Trace: > > > > > [ 1895.979325] ? fastop+0x59/0xa0 [kvm] > > > > > [ 1895.979326] ? x86_emulate_insn+0x73a/0xe00 [kvm] > > > > > [ 1895.979326] ? x86_emulate_instruction+0x2d0/0x750 [kvm] > > > > > [ 1895.979326] ? vmx_vcpu_load+0x21/0x70 [kvm_intel] > > > > > [ 1895.979327] ? complete_emulated_mmio+0x236/0x310 [kvm] > > > > > [ 1895.979327] ? kvm_arch_vcpu_ioctl_run+0x1744/0x1920 [kvm] > > > > > [ 1895.979327] ? kvm_vcpu_ioctl+0x211/0x5a0 [kvm] > > > > > [ 1895.979328] ? __fget_files+0x79/0xb0 > > > > > [ 1895.979328] ? __fget_files+0x79/0xb0 > > > > > [ 1895.979328] ? __x64_sys_ioctl+0x8b/0xc0 > > > > > [ 1895.979329] ? do_syscall_64+0x33/0x40 > > > > > [ 1895.979329] ? entry_SYSCALL_64_after_hwframe+0x61/0xc6 > > ... > > > > > > Is this bug known, any hint how to fix it? > > > > I did more tests on different Servers, so far all the machine > > > > checked(Skylake/Icelake/Haswell/Broadwell/EPYC) crash immediately > > > > except AMD Opteron. > > > > kvm-unit-tests succeeded without regression. > > > > > > Same issue on Linus's tree right now as well? Or does that pass just > > > fine? > > > > Hi Greg, > > > > I haven't try linus tree, but just tried 5.15.55-rc1 on Intel Skylake, > > it crashed the same. > > > > I will give Linus tree a try. > > Looks like fastop() got broken by the retbleed mitigations, i.e. this isn't unique > to stable trees. > > https://lore.kernel.org/all/20220713171241.184026-1-cascardo@xxxxxxxxxxxxx Hi Sean, Thanks for the link, I will give it a try, to apply to kernel 5.10, I adapted it a bit to diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c index 59e5d79f5c34..aa7b5adac633 100644 --- a/arch/x86/kvm/emulate.c +++ b/arch/x86/kvm/emulate.c @@ -189,7 +189,7 @@ #define X16(x...) X8(x), X8(x) #define NR_FASTOP (ilog2(sizeof(ulong)) + 1) -#define FASTOP_SIZE 8 +#define FASTOP_SIZE (8 * (1 + (IS_ENABLED(CONFIG_RETHUNK)))) struct opcode { u64 flags : 56; With it, kvm-unit-tests is working again, no gression found. Thanks!
