From: Benjamin Berg <bberg@redhat.com>

Date: Wed, 9 Oct 2019 17:54:24 +0200

Subject: x86/mce: Lower throttling MCE messages' priority to warning

Git-commit: 9c3bafaa1fd88e4dd2dba3735a1f1abb0f2c7bb7

Patch-mainline: 5.5-rc1

References: git-fixes

On modern CPUs it is quite normal that the temperature limits are

reached and the CPU is throttled. In fact, often the thermal design is

not sufficient to cool the CPU at full load and limits can quickly be

reached when a burst in load happens. This will even happen with

technologies like RAPL limitting the long term power consumption of

the package.

Also, these limits are "softer", as Srinivas explains:

"CPU temperature doesn't have to hit max(TjMax) to get these warnings.

OEMs ha[ve] an ability to program a threshold where a thermal interrupt

can be generated. In some systems the offset is 20C+ (Read only value).

In recent systems, there is another offset on top of it which can be

programmed by OS, once some agent can adjust power limits dynamically.

By default this is set to low by the firmware, which I guess the

prime motivation of Benjamin to submit the patch."

So these messages do not usually indicate a hardware issue (e.g.

insufficient cooling). Log them as warnings to avoid confusion about

their severity.

 [ bp: Massage commit mesage. ]

Signed-off-by: Benjamin Berg <bberg@redhat.com>

Signed-off-by: Borislav Petkov <bp@suse.de>

Reviewed-by: Hans de Goede <hdegoede@redhat.com>

Tested-by: Christian Kellner <ckellner@redhat.com>

Cc: "H. Peter Anvin" <hpa@zytor.com>

Cc: Ingo Molnar <mingo@redhat.com>

Cc: linux-edac <linux-edac@vger.kernel.org>

Cc: Peter Zijlstra <peterz@infradead.org>

Cc: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>

Cc: Thomas Gleixner <tglx@linutronix.de>

Cc: Tony Luck <tony.luck@intel.com>

Cc: x86-ml <x86@kernel.org>

Link: https://lkml.kernel.org/r/20191009155424.249277-1-bberg@redhat.com

Signed-off-by: Jiri Slaby <jslaby@suse.cz>

---

 arch/x86/kernel/cpu/mcheck/therm_throt.c |    2 +-

 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/arch/x86/kernel/cpu/mcheck/therm_throt.c

+++ b/arch/x86/kernel/cpu/mcheck/therm_throt.c

@@ -185,7 +185,7 @@ static void therm_throt_process(bool new

 	/* if we just entered the thermal event */

 	if (new_event) {

 		if (event == THERMAL_THROTTLING_EVENT)

-			pr_crit("CPU%d: %s temperature above threshold, cpu clock throttled (total events = %lu)\n",

+			pr_warn("CPU%d: %s temperature above threshold, cpu clock throttled (total events = %lu)\n",

 				this_cpu,

 				level == CORE_LEVEL ? "Core" : "Package",

 				state->count);