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Shutemov" Cc: linux-arm-kernel@lists.infradead.org, kvmarm@lists.linux.dev, kvm@vger.kernel.org, loongarch@lists.linux.dev, linux-mips@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, kvm-riscv@lists.infradead.org, linux-riscv@lists.infradead.org, x86@kernel.org, linux-coco@lists.linux.dev, linux-kernel@vger.kernel.org, Ira Weiny , Kai Huang , Binbin Wu , Michael Roth , Yan Zhao , Vishal Annapurve , Rick Edgecombe , Ackerley Tng Content-Type: text/plain; charset="UTF-8" Don't copy the kvm_tdx_cmd structure back to userspace when handling KVM_TDX_CAPABILITIES, as tdx_get_capabilities() doesn't modify hw_error or any other fields. Opportunistically hoist the call to tdx_get_capabilities() outside of the kvm->lock critical section, as getting the capabilities doesn't touch the VM in any way, e.g. doesn't even take @kvm. Suggested-by: Kai Huang Signed-off-by: Sean Christopherson --- arch/x86/kvm/vmx/tdx.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c index 037429964fd7..57dfddd2a6cf 100644 --- a/arch/x86/kvm/vmx/tdx.c +++ b/arch/x86/kvm/vmx/tdx.c @@ -2806,12 +2806,12 @@ int tdx_vm_ioctl(struct kvm *kvm, void __user *argp) if (r) return r; + if (tdx_cmd.id == KVM_TDX_CAPABILITIES) + return tdx_get_capabilities(&tdx_cmd); + guard(mutex)(&kvm->lock); switch (tdx_cmd.id) { - case KVM_TDX_CAPABILITIES: - r = tdx_get_capabilities(&tdx_cmd); - break; case KVM_TDX_INIT_VM: r = tdx_td_init(kvm, &tdx_cmd); break; -- 2.51.1.930.gacf6e81ea2-goog