[3.8.y.z extended stable] Patch "x86: fix boot on uniprocessor systems" has been added to staging queue

[Kamal Mostafa]

This is a note to let you know that I have just added a patch titled

    x86: fix boot on uniprocessor systems

to the linux-3.8.y-queue branch of the 3.8.y.z extended stable tree 
which can be found at:

 http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.8.y-queue

This patch is scheduled to be released in version 3.8.13.21.

If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 3.8.y.z tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Kamal

------

>From 089774475bad85842c71d71236c1071e1ef53d6e Mon Sep 17 00:00:00 2001
From: Artem Fetishev <artem_fetishev at epam.com>
Date: Fri, 28 Mar 2014 13:33:39 -0700
Subject: x86: fix boot on uniprocessor systems

commit 825600c0f20e595daaa7a6dd8970f84fa2a2ee57 upstream.

On x86 uniprocessor systems topology_physical_package_id() returns -1
which causes rapl_cpu_prepare() to leave rapl_pmu variable uninitialized
which leads to GPF in rapl_pmu_init().

See arch/x86/kernel/cpu/perf_event_intel_rapl.c.

It turns out that physical_package_id and core_id can actually be
retreived for uniprocessor systems too.  Enabling them also fixes
rapl_pmu code.

Signed-off-by: Artem Fetishev <artem_fetishev at epam.com>
Cc: Stephane Eranian <eranian at google.com>
Cc: Ingo Molnar <mingo at elte.hu>
Cc: "H. Peter Anvin" <hpa at zytor.com>
Cc: Thomas Gleixner <tglx at linutronix.de>
Cc: Peter Zijlstra <a.p.zijlstra at chello.nl>
Signed-off-by: Andrew Morton <akpm at linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds at linux-foundation.org>
Signed-off-by: Kamal Mostafa <kamal at canonical.com>
---
 arch/x86/include/asm/topology.h | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/arch/x86/include/asm/topology.h b/arch/x86/include/asm/topology.h
index 095b215..60bd274 100644
--- a/arch/x86/include/asm/topology.h
+++ b/arch/x86/include/asm/topology.h
@@ -119,9 +119,10 @@ static inline void setup_node_to_cpumask_map(void) { }

 extern const struct cpumask *cpu_coregroup_mask(int cpu);

-#ifdef ENABLE_TOPO_DEFINES
 #define topology_physical_package_id(cpu)	(cpu_data(cpu).phys_proc_id)
 #define topology_core_id(cpu)			(cpu_data(cpu).cpu_core_id)
+
+#ifdef ENABLE_TOPO_DEFINES
 #define topology_core_cpumask(cpu)		(per_cpu(cpu_core_map, cpu))
 #define topology_thread_cpumask(cpu)		(per_cpu(cpu_sibling_map, cpu))

--
1.8.3.2