From 5214a9f6c0f56644acb9d2cbb58facf1856d322b Mon Sep 17 00:00:00 2001 From: "Borislav Petkov (AMD)" Date: Mon, 14 Apr 2025 11:59:33 +0200 Subject: x86/microcode: Consolidate the loader enablement checking MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Consolidate the whole logic which determines whether the microcode loader should be enabled or not into a single function and call it everywhere. Well, almost everywhere - not in mk_early_pgtbl_32() because there the kernel is running without paging enabled and checking dis_ucode_ldr et al would require physical addresses and uglification of the code. But since this is 32-bit, the easier thing to do is to simply map the initrd unconditionally especially since that mapping is getting removed later anyway by zap_early_initrd_mapping() and avoid the uglification. In doing so, address the issue of old 486er machines without CPUID support, not booting current kernels. [ mingo: Fix no previous prototype for ‘microcode_loader_disabled’ [-Wmissing-prototypes] ] Fixes: 4c585af7180c1 ("x86/boot/32: Temporarily map initrd for microcode loading") Signed-off-by: Borislav Petkov (AMD) Signed-off-by: Ingo Molnar Signed-off-by: Borislav Petkov (AMD) Cc: Link: https://lore.kernel.org/r/CANpbe9Wm3z8fy9HbgS8cuhoj0TREYEEkBipDuhgkWFvqX0UoVQ@mail.gmail.com --- arch/x86/include/asm/microcode.h | 2 ++ 1 file changed, 2 insertions(+) (limited to 'arch/x86/include/asm/microcode.h') diff --git a/arch/x86/include/asm/microcode.h b/arch/x86/include/asm/microcode.h index 695e569159c1..be7cddc414e4 100644 --- a/arch/x86/include/asm/microcode.h +++ b/arch/x86/include/asm/microcode.h @@ -17,10 +17,12 @@ struct ucode_cpu_info { void load_ucode_bsp(void); void load_ucode_ap(void); void microcode_bsp_resume(void); +bool __init microcode_loader_disabled(void); #else static inline void load_ucode_bsp(void) { } static inline void load_ucode_ap(void) { } static inline void microcode_bsp_resume(void) { } +static inline bool __init microcode_loader_disabled(void) { return false; } #endif extern unsigned long initrd_start_early; -- cgit v1.2.3