Commit-ID: fa37361e291bfe528872b9aef5c8644a3fc7ff20
Gitweb: http://git.kernel.org/tip/fa37361e291bfe528872b9aef5c8644a3fc7ff20
Author: Prarit Bhargava <[email protected]>
AuthorDate: Thu, 5 Jan 2017 10:09:25 -0500
Committer: Ingo Molnar <[email protected]>
CommitDate: Sat, 7 Jan 2017 08:54:38 +0100
perf/x86/intel/uncore: Fix hardcoded socket 0 assumption in the Haswell init
code
On multi-socket Intel v3 processor systems (aka Haswell), kdump can crash
in hswep_uncore_cpu_init():
BUG: unable to handle kernel paging request at 00000000006563a1
IP: [<ffffffff8101b582>] hswep_uncore_cpu_init+0x52/0xa0
The crash was introduced by the following commit:
9d85eb9119f4 ("x86/smpboot: Make logical package management more robust")
... which patch corrected the physical ID to logical ID mapping of the
threads if the kdumped panic occurs on any socket other than socket 0.
But hswep_uncore_cpu_init() is hard coded for physical socket 0 and if the
system is kdump'ing on any other socket the logical package value will be
incorrect - crashing the kdump kernel.
The code should not use 0 as the physical ID, and should use the boot
CPU's logical package ID in this calculation.
Signed-off-by: Prarit Bhargava <[email protected]>
Cc: Alexander Shishkin <[email protected]>
Cc: Arnaldo Carvalho de Melo <[email protected]>
Cc: Borislav Petkov <[email protected]>
Cc: H. Peter Anvin <[email protected]>
Cc: Harish Chegondi <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Kan Liang <[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]
Signed-off-by: Ingo Molnar <[email protected]>
---
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..dae2fed 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 = boot_cpu_data.logical_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;
