aarch64: fix SME_LUTV2 /proc/cpuinfo flag string (smelutv1 -> smelutv2)#464
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aarch64: fix SME_LUTV2 /proc/cpuinfo flag string (smelutv1 -> smelutv2)#464EylonKrause wants to merge 1 commit into
EylonKrause wants to merge 1 commit into
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The AARCH64_SME_LUTV2 entry used "smelutv1" as its /proc/cpuinfo match string, while its enum name (smelutv2) and HWCAP2 macro (AARCH64_HWCAP2_SME_LUTV2) are both LUTv2. The Linux kernel prints this feature as "smelutv2" (KERNEL_HWCAP_SME_LUTV2 in arch/arm64/kernel/cpuinfo.c), so the /proc/cpuinfo string-scan fallback never matched and never set the SME_LUTV2 bit. It is the sole string-vs-name mismatch among the SME/FP8 entries. Fix it to "smelutv2".
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Description
The
AARCH64_SME_LUTV2entry in the AArch64 feature table uses"smelutv1"as its/proc/cpuinfomatch string, while both its enum name (smelutv2) and its HWCAP2 macro (AARCH64_HWCAP2_SME_LUTV2) are LUTv2. The Linux kernel prints this feature assmelutv2(KERNEL_HWCAP_SME_LUTV2inarch/arm64/kernel/cpuinfo.c), so the/proc/cpuinfostring-scan fallback never matches and never sets theSME_LUTV2bit. It is the sole string-vs-name mismatch among the SME/FP8 entries.The
getauxval(AT_HWCAP2)bit path is unaffected — this only fixes the cpuinfo-scan fallback used whengetauxvalis unavailable.Fix
"smelutv1"→"smelutv2", matching the kernel token and the entry's own name.I don't have AArch64 hardware to exercise the cpuinfo path at runtime, but the fix is verifiable against the kernel's hwcap string table (linked above) and the entry's name / HWCAP2 macro.