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Fri, 6 Nov 2026 05:57:09 +0000 Message-ID: <4b8e0f1b-266c-490c-8a95-008d936d0d6a@intel.com> Date: Thu, 5 Nov 2026 21:57:07 -0800 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v8 03/20] KVM: x86: Support APX state for XSAVE ABI To: Jim Mattson CC: , , , , , References: <20260930210750.1487547-1-chang.seok.bae@intel.com> <20260930210750.1487547-4-chang.seok.bae@intel.com> <24be20bc-4089-4cf9-899b-8da1b2ee2825@intel.com> Content-Language: en-US From: "Chang S. 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> > /* > * Add back in the features that came in from userspace: > */ > xsave->header.xfeatures |= hdr.xfeatures; > > All user-state bits in xsave->header.xfeatures are cleared before > hdr.xfeatures is ORed in. If userspace clears bit i for any user state > component in hdr.xfeatures, bit i in xsave->header.xfeatures is cleared, > and the component is reset to its initial state. Ah, right. Looks like sticking to what I thought before...