diff options
Diffstat (limited to 'common/recipes-kernel/linux/linux-yocto-4.9.21/0005-x86-microcode-AMD-Do-not-load-when-running-on-a-hype.patch')
| -rw-r--r-- | common/recipes-kernel/linux/linux-yocto-4.9.21/0005-x86-microcode-AMD-Do-not-load-when-running-on-a-hype.patch | 105 |
1 files changed, 0 insertions, 105 deletions
diff --git a/common/recipes-kernel/linux/linux-yocto-4.9.21/0005-x86-microcode-AMD-Do-not-load-when-running-on-a-hype.patch b/common/recipes-kernel/linux/linux-yocto-4.9.21/0005-x86-microcode-AMD-Do-not-load-when-running-on-a-hype.patch deleted file mode 100644 index bbb98553..00000000 --- a/common/recipes-kernel/linux/linux-yocto-4.9.21/0005-x86-microcode-AMD-Do-not-load-when-running-on-a-hype.patch +++ /dev/null @@ -1,105 +0,0 @@ -From 56f0eb24f5e9ff1faf0818a928a6c4a1004aeef1 Mon Sep 17 00:00:00 2001 -From: Borislav Petkov <bp@suse.de> -Date: Sun, 18 Dec 2016 17:44:13 +0100 -Subject: [PATCH 05/42] x86/microcode/AMD: Do not load when running on a - hypervisor - -commit a15a753539eca8ba243d576f02e7ca9c4b7d7042 upstream. - -Doing so is completely void of sense for multiple reasons so prevent -it. Set dis_ucode_ldr to true and thus disable the microcode loader by -default to address xen pv guests which execute the AP path but not the -BSP path. - -By having it turned off by default, the APs won't run into the loader -either. - -Also, check CPUID(1).ECX[31] which hypervisors set. Well almost, not the -xen pv one. That one gets the aforementioned "fix". - -Also, improve the detection method by caching the final decision whether -to continue loading in dis_ucode_ldr and do it once on the BSP. The APs -then simply test that value. - -Signed-off-by: Borislav Petkov <bp@suse.de> -Tested-by: Juergen Gross <jgross@suse.com> -Tested-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> -Acked-by: Juergen Gross <jgross@suse.com> -Link: http://lkml.kernel.org/r/20161218164414.9649-4-bp@alien8.de -Signed-off-by: Thomas Gleixner <tglx@linutronix.de> -Cc: Rolf Neugebauer <rolf.neugebauer@docker.com> -Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> ---- - arch/x86/kernel/cpu/microcode/core.c | 28 +++++++++++++++++++--------- - 1 file changed, 19 insertions(+), 9 deletions(-) - -diff --git a/arch/x86/kernel/cpu/microcode/core.c b/arch/x86/kernel/cpu/microcode/core.c -index 5ce5155..dc0b9f8 100644 ---- a/arch/x86/kernel/cpu/microcode/core.c -+++ b/arch/x86/kernel/cpu/microcode/core.c -@@ -43,7 +43,7 @@ - #define MICROCODE_VERSION "2.01" - - static struct microcode_ops *microcode_ops; --static bool dis_ucode_ldr; -+static bool dis_ucode_ldr = true; - - /* - * Synchronization. -@@ -73,6 +73,7 @@ struct cpu_info_ctx { - static bool __init check_loader_disabled_bsp(void) - { - static const char *__dis_opt_str = "dis_ucode_ldr"; -+ u32 a, b, c, d; - - #ifdef CONFIG_X86_32 - const char *cmdline = (const char *)__pa_nodebug(boot_command_line); -@@ -85,8 +86,23 @@ static bool __init check_loader_disabled_bsp(void) - bool *res = &dis_ucode_ldr; - #endif - -- if (cmdline_find_option_bool(cmdline, option)) -- *res = true; -+ if (!have_cpuid_p()) -+ return *res; -+ -+ a = 1; -+ c = 0; -+ native_cpuid(&a, &b, &c, &d); -+ -+ /* -+ * CPUID(1).ECX[31]: reserved for hypervisor use. This is still not -+ * completely accurate as xen pv guests don't see that CPUID bit set but -+ * that's good enough as they don't land on the BSP path anyway. -+ */ -+ if (c & BIT(31)) -+ return *res; -+ -+ if (cmdline_find_option_bool(cmdline, option) <= 0) -+ *res = false; - - return *res; - } -@@ -118,9 +134,6 @@ void __init load_ucode_bsp(void) - if (check_loader_disabled_bsp()) - return; - -- if (!have_cpuid_p()) -- return; -- - vendor = x86_cpuid_vendor(); - family = x86_cpuid_family(); - -@@ -154,9 +167,6 @@ void load_ucode_ap(void) - if (check_loader_disabled_ap()) - return; - -- if (!have_cpuid_p()) -- return; -- - vendor = x86_cpuid_vendor(); - family = x86_cpuid_family(); - --- -2.7.4 - |