linux-kernel - [PATCH 3/3] x86/mce/amd: apply MC4_MISC thresholding quirk in resume path

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Date:   Thu, 10 Jan 2019 07:54:57 +0000
From:   "S, Shirish" <Shirish.S@....com>
To:     --cc=Borislav Petkov <bp@...en8.de>
CC:     Thomas Gleixner <tglx@...utronix.de>,
        Ingo Molnar <mingo@...hat.com>,
        "H . Peter Anvin" <hpa@...or.com>,
        "maintainer : X86 ARCHITECTURE" <x86@...nel.org>,
        Tony Luck <tony.luck@...el.com>,
        Vishal Verma <vishal.l.verma@...el.com>,
        "open list : X86 ARCHITECTURE" <linux-kernel@...r.kernel.org>,
        "S, Shirish" <Shirish.S@....com>
Subject: [PATCH 3/3] x86/mce/amd: apply MC4_MISC thresholding quirk in resume
 path

There are 2 code paths leading to mce_amd_feature_init() as below.
1) S5 -> S0: (boot)
secondary_startup_64 -> start_kernel -> identify_boot_cpu ->
identify_cpu ->
mcheck_cpu_init (calls  __mcheck_cpu_apply_quirks before) ->
mce_amd_feature_init

2) S3 -> S0: (resume)
syscore_resume -> mce_syscore_resume -> mce_amd_feature_init

Its clear that the quirks are not applied in S3 -> S0 path, hence apply
the same.

Signed-off-by: Shirish S <shirish.s@....com>
---
 arch/x86/kernel/cpu/mce/amd.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/arch/x86/kernel/cpu/mce/amd.c b/arch/x86/kernel/cpu/mce/amd.c
index 89298c8..ab1b12a 100644
--- a/arch/x86/kernel/cpu/mce/amd.c
+++ b/arch/x86/kernel/cpu/mce/amd.c
@@ -552,6 +552,12 @@ void mce_amd_feature_init(struct cpuinfo_x86 *c)
 	unsigned int bank, block, cpu = smp_processor_id();
 	int offset = -1;
 
+	/*
+	 * mcheck_cpu_init() is not called when called by mce_syscore_resume(),
+	 * hence re-apply quirks, to be on safer side.
+	 */
+	quirk_fam15_mc4_misc_thresholding();
+
 	for (bank = 0; bank < mca_cfg.banks; ++bank) {
 		if (mce_flags.smca)
 			smca_configure(bank, cpu);
-- 
2.7.4