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Mon, 9 Mar 2026 23:47:51 +0000 Message-ID: Date: Mon, 9 Mar 2026 16:47:49 -0700 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v8 1/3] x86/cpu: Clear feature bits disabled at compile-time Content-Language: en-US To: Maciej Wieczor-Retman , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , , "H. 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> +__u32 cpu_caps_cleared[NCAPINTS + NBUGINTS] __aligned(sizeof(unsigned long)) = > + DISABLED_MASK_INITIALIZER; IIUC, DISABLED_MASK_INITIALIZER only contains the X86_FEATURE_* bits. So, the NBUGINTS bits in cpu_caps_cleared[] are implicitly set to 0. Should that be mentioned in the comment above? It wasn't obvious to me when I first looked at it. > __u32 cpu_caps_set[NCAPINTS + NBUGINTS] __aligned(sizeof(unsigned long)); > > #ifdef CONFIG_X86_32 > diff --git a/arch/x86/tools/cpufeaturemasks.awk b/arch/x86/tools/cpufeaturemasks.awk > index 173d5bf2d999..b7f4e775a365 100755 > --- a/arch/x86/tools/cpufeaturemasks.awk > +++ b/arch/x86/tools/cpufeaturemasks.awk > @@ -82,6 +82,12 @@ END { > } > printf " 0\t\\\n"; > printf "\t) & (1U << ((x) & 31)))\n\n"; > + > + printf "\n#define %s_MASK_INITIALIZER\t\t\t\\", s; > + printf "\n\t{\t\t\t\t\t\t\\"; > + for (i = 0; i < ncapints; i++) > + printf "\n\t\t%s_MASK%d,\t\t\t\\", s, i; > + printf "\n\t}\n\n"; > } > > printf "#endif /* _ASM_X86_CPUFEATUREMASKS_H */\n";