Minki/linux
1
0
Fork 1
mirror of https://github.com/torvalds/linux.git synced 2024-11-07 12:41:55 +00:00
Code Issues Packages Projects Releases Wiki Activity

x86, amd, mce: Avoid NULL pointer reference on CPU northbridge lookup

Browse Source 
When booting on a federated multi-server system (NumaScale), the
processor Northbridge lookup returns NULL; add guards to prevent this
causing an oops.

On those systems, the northbridge is accessed through MMIO and the
"normal" northbridge enumeration in amd_nb.c doesn't work since we're
generating the northbridge ID from the initial APIC ID and the last
is not unique on those systems. Long story short, we end up without
northbridge descriptors.

Signed-off-by: Daniel J Blueman <daniel@numascale-asia.com>
Cc: stable@vger.kernel.org # 3.6
Link: http://lkml.kernel.org/r/1349073725-14093-1-git-send-email-daniel@numascale-asia.com
[ Boris: beef up commit message ]
Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
This commit is contained in:
Daniel J Blueman 2012-10-01 14:42:05 +08:00 committed by H. Peter Anvin
parent 1bbbbe779a
commit 21c5e50e15
1 changed files with 5 additions and 5 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

10
arch/x86/kernel/cpu/mcheck/mce_amd.c
View File

@ -576,12 +576,10 @@ static __cpuinit int threshold_create_bank(unsigned int cpu, unsigned int bank)
int err = 0;
if (shared_bank[bank]) {
nb = node_to_amd_nb(amd_get_nb_id(cpu));
WARN_ON(!nb);
/* threshold descriptor already initialized on this node? */
if (nb->bank4) {
if (nb && nb->bank4) {
/* yes, use it */
b = nb->bank4;
err = kobject_add(b->kobj, &dev->kobj, name);
@ -615,8 +613,10 @@ static __cpuinit int threshold_create_bank(unsigned int cpu, unsigned int bank)
atomic_set(&b->cpus, 1);
/* nb is already initialized, see above */
WARN_ON(nb->bank4);
nb->bank4 = b;
if (nb) {
WARN_ON(nb->bank4);
nb->bank4 = b;
}
}
err = allocate_threshold_blocks(cpu, bank, 0,