Commit ee38a907 authored by Borislav Petkov's avatar Borislav Petkov Committed by Ingo Molnar

x86/microcode: Disable builtin microcode loading on 32-bit for now

Andy Shevchenko reported machine freezes when booting latest tip
on 32-bit setups. Problem is, the builtin microcode handling cannot
really work that early, when we haven't even enabled paging.

A proper fix would involve handling that case specially as every
other early 32-bit boot case in the microcode loader and would
require much more involved changes for which it is too late now,
more than a week before the upcoming merge window.

So, disable the builtin microcode loading on 32-bit for now.
Reported-and-tested-by: default avatarAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: default avatarBorislav Petkov <bp@suse.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1433436928-31903-20-git-send-email-bp@alien8.deSigned-off-by: default avatarIngo Molnar <mingo@kernel.org>
parent e774eaa9
......@@ -230,6 +230,7 @@ static void apply_ucode_in_initrd(void *ucode, size_t size, bool save_patch)
static bool __init load_builtin_amd_microcode(struct cpio_data *cp, int family)
{
#ifdef CONFIG_X86_64
char fw_name[36] = "amd-ucode/microcode_amd.bin";
if (family >= 0x15)
......@@ -237,6 +238,9 @@ static bool __init load_builtin_amd_microcode(struct cpio_data *cp, int family)
"amd-ucode/microcode_amd_fam%.2xh.bin", family);
return get_builtin_firmware(cp, fw_name);
#else
return false;
#endif
}
void __init load_ucode_amd_bsp(int family)
......
......@@ -523,6 +523,7 @@ EXPORT_SYMBOL_GPL(save_mc_for_early);
static bool __init load_builtin_intel_microcode(struct cpio_data *cp)
{
#ifdef CONFIG_X86_64
u32 eax = 0x00000001, ebx, ecx = 0, edx;
int family, model, stepping;
char name[30];
......@@ -536,6 +537,9 @@ static bool __init load_builtin_intel_microcode(struct cpio_data *cp)
sprintf(name, "intel-ucode/%02x-%02x-%02x", family, model, stepping);
return get_builtin_firmware(cp, name);
#else
return false;
#endif
}
static __initdata char ucode_name[] = "kernel/x86/microcode/GenuineIntel.bin";
......
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