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charset="us-ascii" On Fri, Sep 06, 2024, Shakeel Butt wrote: > On Mon, Sep 02, 2024 at 02:42:19PM GMT, Tom Dohrmann wrote: > > Until recently, KVM_CAP_READONLY_MEM was unconditionally supported on > > x86, but this is no longer the case for SEV-ES and SEV-SNP VMs. > > > > When KVM_CHECK_EXTENSION is invoked on a VM, only advertise > > KVM_CAP_READONLY_MEM when it's actually supported. > > > > Fixes: 66155de93bcf ("KVM: x86: Disallow read-only memslots for SEV-ES and SEV-SNP (and TDX)") > > Cc: Sean Christopherson > > Cc: Paolo Bonzini > > Cc: Michael Roth > > Signed-off-by: Tom Dohrmann > > --- > > arch/x86/kvm/x86.c | 3 ++- > > 1 file changed, 2 insertions(+), 1 deletion(-) > > > > diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c > > index 70219e406987..9ad7fe279e72 100644 > > --- a/arch/x86/kvm/x86.c > > +++ b/arch/x86/kvm/x86.c > > @@ -4656,7 +4656,6 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext) > > case KVM_CAP_ASYNC_PF_INT: > > case KVM_CAP_GET_TSC_KHZ: > > case KVM_CAP_KVMCLOCK_CTRL: > > - case KVM_CAP_READONLY_MEM: > > case KVM_CAP_IOAPIC_POLARITY_IGNORED: > > case KVM_CAP_TSC_DEADLINE_TIMER: > > case KVM_CAP_DISABLE_QUIRKS: > > @@ -4815,6 +4814,8 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext) > > case KVM_CAP_VM_TYPES: > > r = kvm_caps.supported_vm_types; > > break; > > + case KVM_CAP_READONLY_MEM: > > + r = kvm ? kvm_arch_has_readonly_mem(kvm) : 1; > > Need a break here otherwise -Wimplicit-fallthrough option will warn. Heh, Nathan beat you to it: https://lore.kernel.org/all/20240905-kvm-x86-avoid-clang-implicit-fallthrough-v1-1-f2e785f1aa45@kernel.org