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Wed, 7 Jan 2026 00:28:56 +0000 Message-ID: Date: Tue, 6 Jan 2026 16:28:54 -0800 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH 1/4] x86/fpu: Clear XSTATE_BV[i] in save state whenever XFD[i]=1 To: Paolo Bonzini , , CC: , , References: <20260101090516.316883-1-pbonzini@redhat.com> <20260101090516.316883-2-pbonzini@redhat.com> Content-Language: en-US From: "Chang S. 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I’m not sure whether the repetition is intentional. > preemptible kernels, and it we can consider it (de facto) part of KVM ^^^^^ I assume you meant 'we' here though, you might want to slightly rephrase it, given the previous debate: https://lore.kernel.org/all/87iko54f42.ffs@tglx/ > ABI that KVM_GET_XSAVE returns XSTATE_BV[i]=0 for XFD-disabled features. On my side, testing on AMX systems, I was able to reproduce the issue described and confirm that this patch resolves it: Tested-by: Chang S. Bae The added guards on these paths also look reasonable to me with the established KVM ABI. So, Reviewed-by: Chang S. Bae Thanks, Chang