Re: [PATCH -next] kvm/svm: disable KCSAN for svm_vcpu_run()

[Qian Cai]

> On Apr 15, 2020, at 11:57 AM, Paolo Bonzini <pbonzini@xxxxxxxxxx> wrote:
> 
> On 15/04/20 17:37, Qian Cai wrote:
>> For some reasons, running a simple qemu-kvm command with KCSAN will
>> reset AMD hosts. It turns out svm_vcpu_run() could not be instrumented.
>> Disable it for now.
>> 
>> # /usr/libexec/qemu-kvm -name ubuntu-18.04-server-cloudimg -cpu host
>> 	-smp 2 -m 2G -hda ubuntu-18.04-server-cloudimg.qcow2
>> 
>> === console output ===
>> Kernel 5.6.0-next-20200408+ on an x86_64
>> 
>> hp-dl385g10-05 login:
>> 
>> <...host reset...>
>> 
>> HPE ProLiant System BIOS A40 v1.20 (03/09/2018)
>> (C) Copyright 1982-2018 Hewlett Packard Enterprise Development LP
>> Early system initialization, please wait...
>> 
>> Signed-off-by: Qian Cai <cai@xxxxxx>
>> ---
>> arch/x86/kvm/svm/svm.c | 2 +-
>> 1 file changed, 1 insertion(+), 1 deletion(-)
>> 
>> diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
>> index 2be5bbae3a40..1fdb300e9337 100644
>> --- a/arch/x86/kvm/svm/svm.c
>> +++ b/arch/x86/kvm/svm/svm.c
>> @@ -3278,7 +3278,7 @@ static void svm_cancel_injection(struct kvm_vcpu *vcpu)
>> 
>> bool __svm_vcpu_run(unsigned long vmcb_pa, unsigned long *regs);
>> 
>> -static void svm_vcpu_run(struct kvm_vcpu *vcpu)
>> +static __no_kcsan void svm_vcpu_run(struct kvm_vcpu *vcpu)
>> {
>> 	struct vcpu_svm *svm = to_svm(vcpu);
>> 
>> 
> 
> I suppose you tested the patch to move cli/sti into the .S file.  Anyway:

Yes, tested that without any luck.