diff options
Diffstat (limited to 'common/recipes-kernel/linux/linux-yocto-4.9.21/0041-x86-microcode-Do-the-family-check-first.patch')
| -rw-r--r-- | common/recipes-kernel/linux/linux-yocto-4.9.21/0041-x86-microcode-Do-the-family-check-first.patch | 94 |
1 files changed, 94 insertions, 0 deletions
diff --git a/common/recipes-kernel/linux/linux-yocto-4.9.21/0041-x86-microcode-Do-the-family-check-first.patch b/common/recipes-kernel/linux/linux-yocto-4.9.21/0041-x86-microcode-Do-the-family-check-first.patch new file mode 100644 index 00000000..1f502096 --- /dev/null +++ b/common/recipes-kernel/linux/linux-yocto-4.9.21/0041-x86-microcode-Do-the-family-check-first.patch @@ -0,0 +1,94 @@ +From e614d84ae1ca7bad08645003fb3195a80fbdaae1 Mon Sep 17 00:00:00 2001 +From: Borislav Petkov <bp@suse.de> +Date: Thu, 12 Oct 2017 13:23:16 +0200 +Subject: [PATCH 41/42] x86/microcode: Do the family check first + +commit 1f161f67a272cc4f29f27934dd3f74cb657eb5c4 upstream with adjustments. + +On CPUs like AMD's Geode, for example, we shouldn't even try to load +microcode because they do not support the modern microcode loading +interface. + +However, we do the family check *after* the other checks whether the +loader has been disabled on the command line or whether we're running in +a guest. + +So move the family checks first in order to exit early if we're being +loaded on an unsupported family. + +Reported-and-tested-by: Sven Glodowski <glodi1@arcor.de> +Signed-off-by: Borislav Petkov <bp@suse.de> +Cc: <stable@vger.kernel.org> # 4.11.. +Cc: Linus Torvalds <torvalds@linux-foundation.org> +Cc: Peter Zijlstra <peterz@infradead.org> +Cc: Thomas Gleixner <tglx@linutronix.de> +Link: http://bugzilla.suse.com/show_bug.cgi?id=1061396 +Link: http://lkml.kernel.org/r/20171012112316.977-1-bp@alien8.de +Signed-off-by: Ingo Molnar <mingo@kernel.org> +Signed-off-by: Rolf Neugebauer <rolf.neugebauer@docker.com> +Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> +--- + arch/x86/kernel/cpu/microcode/core.c | 27 ++++++++++++++++++--------- + 1 file changed, 18 insertions(+), 9 deletions(-) + +diff --git a/arch/x86/kernel/cpu/microcode/core.c b/arch/x86/kernel/cpu/microcode/core.c +index dc0b9f8..0afaf00 100644 +--- a/arch/x86/kernel/cpu/microcode/core.c ++++ b/arch/x86/kernel/cpu/microcode/core.c +@@ -86,9 +86,6 @@ static bool __init check_loader_disabled_bsp(void) + bool *res = &dis_ucode_ldr; + #endif + +- if (!have_cpuid_p()) +- return *res; +- + a = 1; + c = 0; + native_cpuid(&a, &b, &c, &d); +@@ -130,8 +127,9 @@ void __init load_ucode_bsp(void) + { + int vendor; + unsigned int family; ++ bool intel = true; + +- if (check_loader_disabled_bsp()) ++ if (!have_cpuid_p()) + return; + + vendor = x86_cpuid_vendor(); +@@ -139,16 +137,27 @@ void __init load_ucode_bsp(void) + + switch (vendor) { + case X86_VENDOR_INTEL: +- if (family >= 6) +- load_ucode_intel_bsp(); ++ if (family < 6) ++ return; + break; ++ + case X86_VENDOR_AMD: +- if (family >= 0x10) +- load_ucode_amd_bsp(family); ++ if (family < 0x10) ++ return; ++ intel = false; + break; ++ + default: +- break; ++ return; + } ++ ++ if (check_loader_disabled_bsp()) ++ return; ++ ++ if (intel) ++ load_ucode_intel_bsp(); ++ else ++ load_ucode_amd_bsp(family); + } + + static bool check_loader_disabled_ap(void) +-- +2.7.4 + |