Commit a7939f01 authored by Thomas Gleixner's avatar Thomas Gleixner Committed by Borislav Petkov (AMD)
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x86/microcode/amd: Cache builtin/initrd microcode early 



There is no reason to scan builtin/initrd microcode on each AP.

Cache the builtin/initrd microcode in an early initcall so that the
early AP loader can utilize the cache.

The existing fs initcall which invoked save_microcode_in_initrd_amd() is
still required to maintain the initrd_gone flag. Rename it accordingly.
This will be removed once the AP loader code is converted to use the
cache.

Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
Signed-off-by: default avatarBorislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/r/20231017211723.187566507@linutronix.de
parent d419d282

arch/x86/kernel/cpu/microcode/amd.c

+7 −1
Original line number Diff line number Diff line
@@ -527,12 +527,17 @@ void load_ucode_amd_early(unsigned int cpuid_1_eax) 


static enum ucode_state load_microcode_amd(u8 family, const u8 *data, size_t size);



int __init save_microcode_in_initrd_amd(unsigned int cpuid_1_eax)

static int __init save_microcode_in_initrd(void)

{

	unsigned int cpuid_1_eax = native_cpuid_eax(1);

	struct cpuinfo_x86 *c = &boot_cpu_data;

	struct cont_desc desc = { 0 };

	enum ucode_state ret;

	struct cpio_data cp;



	if (dis_ucode_ldr || c->x86_vendor != X86_VENDOR_AMD || c->x86 < 0x10)

		return 0;



	find_blobs_in_containers(cpuid_1_eax, &cp);

	if (!(cp.data && cp.size))

		return -EINVAL;
@@ -549,6 +554,7 @@ int __init save_microcode_in_initrd_amd(unsigned int cpuid_1_eax) 


	return 0;

}

early_initcall(save_microcode_in_initrd);



/*

 * a small, trivial cache of per-family ucode patches

arch/x86/kernel/cpu/microcode/core.c

+4 −16
Original line number Diff line number Diff line
@@ -180,24 +180,13 @@ void load_ucode_ap(void) 
	}

}



static int __init save_microcode_in_initrd(void)

/* Temporary workaround until find_microcode_in_initrd() is __init */

static int __init mark_initrd_gone(void)

{

	struct cpuinfo_x86 *c = &boot_cpu_data;

	int ret = -EINVAL;



	switch (c->x86_vendor) {

	case X86_VENDOR_AMD:

		if (c->x86 >= 0x10)

			ret = save_microcode_in_initrd_amd(cpuid_eax(1));

		break;

	default:

		break;

	}



	initrd_gone = true;



	return ret;

	return 0;

}

fs_initcall(mark_initrd_gone);



struct cpio_data find_microcode_in_initrd(const char *path)

{
@@ -615,5 +604,4 @@ static int __init microcode_init(void) 
	return error;



}

fs_initcall(save_microcode_in_initrd);

late_initcall(microcode_init);