Re: [PATCH v6 2/9] x86/cpu: KVM: Move macro to encode PAT value to common header

Huang, Kai
2024-04-03T21:03:57Z

> void __init pat_bp_init(void)
> {
> struct cpuinfo_x86 *c = &boot_cpu_data;
> -#define PAT(p0, p1, p2, p3, p4, p5, p6, p7) \
> - ((X86_MEMTYPE_ ## p0) | (X86_MEMTYPE_ ## p1 << 8) | \
> - (X86_MEMTYPE_ ## p2 << 16) | (X86_MEMTYPE_ ## p3 << 24) | \
> - (X86_MEMTYPE_ ## p4 << 32) | (X86_MEMTYPE_ ## p5 << 40) | \
> - (X86_MEMTYPE_ ## p6 << 48) | (X86_MEMTYPE_ ## p7 << 56))
> -
>
> if (!IS_ENABLED(CONFIG_X86_PAT))
> pr_info_once("x86/PAT: PAT support disabled because CONFIG_X86_PAT is disabled in the kernel.\n");
> @@ -281,7 +275,7 @@ void __init pat_bp_init(void)
> * NOTE: When WC or WP is used, it is redirected to UC- per
> * the default setup in __cachemode2pte_tbl[].
> */
> - pat_msr_val = PAT(WB, WT, UC_MINUS, UC, WB, WT, UC_MINUS, UC);
> + pat_msr_val = PAT_VALUE(WB, WT, UC_MINUS, UC, WB, WT, UC_MINUS, UC);
> }
>
> /*
> @@ -321,7 +315,7 @@ void __init pat_bp_init(void)
> * NOTE: When WT or WP is used, it is redirected to UC- per
> * the default setup in __cachemode2pte_tbl[].
> */
> - pat_msr_val = PAT(WB, WC, UC_MINUS, UC, WB, WC, UC_MINUS, UC);
> + pat_msr_val = PAT_VALUE(WB, WC, UC_MINUS, UC, WB, WC, UC_MINUS, UC);
> } else {
> /*
> * Full PAT support. We put WT in slot 7 to improve
> @@ -349,7 +343,7 @@ void __init pat_bp_init(void)
> * The reserved slots are unused, but mapped to their
> * corresponding types in the presence of PAT errata.
> */
> - pat_msr_val = PAT(WB, WC, UC_MINUS, UC, WB, WP, UC_MINUS, WT);
> + pat_msr_val = PAT_VALUE(WB, WC, UC_MINUS, UC, WB, WP, UC_MINUS, WT);
> }
>
> memory_caching_control |= CACHE_PAT;

I found there's one "#undef PAT" at the end of pat_bp_init() and it
should be removed:

void __init pat_bp_init(void)
{
struct cpuinfo_x86 *c = &boot_cpu_data;
#define PAT(p0, p1, p2, p3, p4, p5, p6, p7) \
(((u64)PAT_ ## p0) | ((u64)PAT_ ## p1 << 8) | \
((u64)PAT_ ## p2 << 16) | ((u64)PAT_ ## p3 << 24) | \
((u64)PAT_ ## p4 << 32) | ((u64)PAT_ ## p5 << 40) | \
((u64)PAT_ ## p6 << 48) | ((u64)PAT_ ## p7 << 56))

...

memory_caching_control |= CACHE_PAT;

init_cache_modes(pat_msr_val);
#undef PAT
}