[tip:x86/urgent] perf/x86/intel/uncore: Do not use hard coded physical package id 0

[tip-bot for Prarit Bhargava <tipbot@zytor.com>]

Commit-ID:  42433049c51e326baa1f45c834af9572fdb65b35
Gitweb:     http://git.kernel.org/tip/42433049c51e326baa1f45c834af9572fdb65b35
Author:     Prarit Bhargava <prarit@redhat.com>
AuthorDate: Tue, 3 Jan 2017 14:24:31 -0500
Committer:  Thomas Gleixner <tglx@linutronix.de>
CommitDate: Wed, 11 Jan 2017 11:29:37 +0100

perf/x86/intel/uncore: Do not use hard coded physical package id 0

hswep_uncore_cpu_init() uses a hardcoded physical package id 0 for the boot
cpu. This works as long as the boot CPU is actually on the physical package
0, which is normaly the case after power on / reboot.

But it fails with a NULL pointer dereference when a kdump kernel is started
on a secondary socket which has a different physical package id because the
locigal package translation for physical package 0 does not exist.

Use the physical package id of the boot cpu instead of hard coded 0.

[ tglx: Rewrote changelog once more ]

commit cf6d445f6897 ("perf/x86/uncore: Track packages, not per CPU data")
Signed-off-by: Prarit Bhargava <prarit@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Harish Chegondi <harish.chegondi@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/1483471471-14450-1-git-send-email-prarit@redhat.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
---
 arch/x86/events/intel/uncore_snbep.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/events/intel/uncore_snbep.c b/arch/x86/events/intel/uncore_snbep.c
index e6832be..b5fbb59 100644
--- a/arch/x86/events/intel/uncore_snbep.c
+++ b/arch/x86/events/intel/uncore_snbep.c
@@ -2686,7 +2686,7 @@ static struct intel_uncore_type *hswep_msr_uncores[] = {
 
 void hswep_uncore_cpu_init(void)
 {
-	int pkg = topology_phys_to_logical_pkg(0);
+	int pkg = topology_phys_to_logical_pkg(boot_cpu_data.phys_proc_id);
 
 	if (hswep_uncore_cbox.num_boxes > boot_cpu_data.x86_max_cores)
 		hswep_uncore_cbox.num_boxes = boot_cpu_data.x86_max_cores;