summaryrefslogtreecommitdiff
path: root/arch
diff options
context:
space:
mode:
authorAshok Raj <ashok.raj@intel.com>2018-02-28 13:28:42 +0300
committerThomas Gleixner <tglx@linutronix.de>2018-03-08 12:19:25 +0300
commit91df9fdf51492aec9fed6b4cbd33160886740f47 (patch)
tree940c5fe62a3610aaa1c1b954c151b41fa02de41d /arch
parentc182d2b7d0ca48e0d6ff16f7d883161238c447ed (diff)
downloadlinux-91df9fdf51492aec9fed6b4cbd33160886740f47.tar.xz
x86/microcode/intel: Writeback and invalidate caches before updating microcode
Updating microcode is less error prone when caches have been flushed and depending on what exactly the microcode is updating. For example, some of the issues around certain Broadwell parts can be addressed by doing a full cache flush. [ Borislav: Massage it and use native_wbinvd() in both cases. ] Signed-off-by: Ashok Raj <ashok.raj@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Tom Lendacky <thomas.lendacky@amd.com> Tested-by: Ashok Raj <ashok.raj@intel.com> Cc: Arjan Van De Ven <arjan.van.de.ven@intel.com> Link: http://lkml.kernel.org/r/1519352533-15992-3-git-send-email-ashok.raj@intel.com Link: https://lkml.kernel.org/r/20180228102846.13447-4-bp@alien8.de
Diffstat (limited to 'arch')
-rw-r--r--arch/x86/kernel/cpu/microcode/intel.c12
1 files changed, 12 insertions, 0 deletions
diff --git a/arch/x86/kernel/cpu/microcode/intel.c b/arch/x86/kernel/cpu/microcode/intel.c
index 87bd6dc94081..e2864bc2d575 100644
--- a/arch/x86/kernel/cpu/microcode/intel.c
+++ b/arch/x86/kernel/cpu/microcode/intel.c
@@ -600,6 +600,12 @@ static int apply_microcode_early(struct ucode_cpu_info *uci, bool early)
return UCODE_OK;
}
+ /*
+ * Writeback and invalidate caches before updating microcode to avoid
+ * internal issues depending on what the microcode is updating.
+ */
+ native_wbinvd();
+
/* write microcode via MSR 0x79 */
native_wrmsrl(MSR_IA32_UCODE_WRITE, (unsigned long)mc->bits);
@@ -816,6 +822,12 @@ static enum ucode_state apply_microcode_intel(int cpu)
return UCODE_OK;
}
+ /*
+ * Writeback and invalidate caches before updating microcode to avoid
+ * internal issues depending on what the microcode is updating.
+ */
+ native_wbinvd();
+
/* write microcode via MSR 0x79 */
wrmsrl(MSR_IA32_UCODE_WRITE, (unsigned long)mc->bits);