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Sat, 8 Aug 2026 03:05:17 +0000 Message-ID: <50bcc6cc-39c7-4207-aa0c-0b1007d97b30@intel.com> Date: Fri, 7 Aug 2026 20:05:13 -0700 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH 09/10] x86/fpu: Allow restoring signal frames with larger xstate_size To: Andrei Vagin CC: Andrei Vagin , Thomas Gleixner , "Ingo Molnar" , Borislav Petkov , , , Dave Hansen , , "H. Peter Anvin" References: <20260615193716.1843340-1-avagin@google.com> <20260615193716.1843340-10-avagin@google.com> <358834b6-86da-4f7f-b2b8-cda31663682d@intel.com> <1bc74033-ba54-49e1-b548-6742deedf1bf@intel.com> <0be62adf-a225-4c35-b526-6b216355797d@intel.com> Content-Language: en-US From: "Chang S. 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ARCH_GET_XCOMP_SUPP stores the supported features in userspace storage of type uint64_t. The second argument is a pointer to that storage. -ARCH_GET_XCOMP_PERM arch_prctl(ARCH_GET_XCOMP_PERM, &features); ARCH_GET_XCOMP_PERM stores the features for which the userspace process has permission in userspace storage of type uint64_t. The second argument is a pointer to that storage. Do you need something else than these? Thanks, Chang