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Patch "perf/x86/intel/uncore: Fix uncore num_counters" has been added to the 4.7-stable tree

PATCH [email protected] 1 participant 1 message Aug 18, 2016

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This is a note to let you know that I've just added the patch titled

perf/x86/intel/uncore: Fix uncore num_counters

to the 4.7-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
perf-x86-intel-uncore-fix-uncore-num_counters.patch
and it can be found in the queue-4.7 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

Quoted 1 line

From 10e9e7bd598f9a66a11a22514c68c13c41fc821b Mon Sep 17 00:00:00 2001

From: Kan Liang <[email protected]>
Date: Thu, 11 Aug 2016 07:30:20 -0700
Subject: perf/x86/intel/uncore: Fix uncore num_counters

From: Kan Liang <[email protected]>

commit 10e9e7bd598f9a66a11a22514c68c13c41fc821b upstream.

Some uncore boxes' num_counters value for Haswell server and Broadwell server are not correct (too large, off by one).

This issue was found by comparing the code with the document. Although there is no bug report from users yet, accessing non-existent counters is dangerous and the behavior is undefined: it may cause miscounting or even crashes.

This patch makes them consistent with the uncore document.

Reported-by Lukasz Odzioba <[email protected]>
Signed-off-by Kan Liang <[email protected]>
Cc Alexander Shishkin <[email protected]>
Cc Arnaldo Carvalho de Melo <[email protected]>
Cc Jiri Olsa <[email protected]>
Cc Linus Torvalds <[email protected]>
Cc Peter Zijlstra <[email protected]>
Cc Stephane Eranian <[email protected]>
Cc Thomas Gleixner <[email protected]>
Cc Vince Weaver <[email protected]>
Link http://lkml.kernel.org/r/[email protected] open here
Signed-off-by Ingo Molnar <[email protected]>
Signed-off-by Greg Kroah-Hartman <[email protected]>
---
 arch/x86/events/intel/uncore_snbep.c |   10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)
arch/x86/events/intel/uncore_snbep.c +5 -5
@@ -2546,7 +2546,7 @@ void hswep_uncore_cpu_init(void)
 
 static struct intel_uncore_type hswep_uncore_ha = {
 	.name		= "ha",
-	.num_counters   = 5,
+	.num_counters   = 4,
 	.num_boxes	= 2,
 	.perf_ctr_bits	= 48,
 	SNBEP_UNCORE_PCI_COMMON_INIT(),

@@ -2565,7 +2565,7 @@ static struct uncore_event_desc hswep_un
 
 static struct intel_uncore_type hswep_uncore_imc = {
 	.name		= "imc",
-	.num_counters   = 5,
+	.num_counters   = 4,
 	.num_boxes	= 8,
 	.perf_ctr_bits	= 48,
 	.fixed_ctr_bits	= 48,

@@ -2611,7 +2611,7 @@ static struct intel_uncore_type hswep_un
 
 static struct intel_uncore_type hswep_uncore_qpi = {
 	.name			= "qpi",
-	.num_counters		= 5,
+	.num_counters		= 4,
 	.num_boxes		= 3,
 	.perf_ctr_bits		= 48,
 	.perf_ctr		= SNBEP_PCI_PMON_CTR0,

@@ -2693,7 +2693,7 @@ static struct event_constraint hswep_unc
 
 static struct intel_uncore_type hswep_uncore_r3qpi = {
 	.name		= "r3qpi",
-	.num_counters   = 4,
+	.num_counters   = 3,
 	.num_boxes	= 3,
 	.perf_ctr_bits	= 44,
 	.constraints	= hswep_uncore_r3qpi_constraints,

@@ -2892,7 +2892,7 @@ static struct intel_uncore_type bdx_unco
 
 static struct intel_uncore_type bdx_uncore_imc = {
 	.name		= "imc",
-	.num_counters   = 5,
+	.num_counters   = 4,
 	.num_boxes	= 8,
 	.perf_ctr_bits	= 48,
 	.fixed_ctr_bits	= 48,

Patches currently in stable-queue which might be from [email protected] are

queue-4.7/perf-x86-intel-uncore-fix-uncore-num_counters.patch