path: root/arch
diff options
authorBorislav Petkov <>2016-06-16 19:13:49 +0200
committerIngo Molnar <>2016-07-01 09:35:35 +0200
commit1ead852dd88779eda12cb09cc894a03d9abfe1ec (patch)
tree54ac3a80addab9db944052d1a31f539d7eb0924a /arch
parent8d950d2fb23b696d393020486ab6a350bcb2c582 (diff)
x86/amd_nb: Fix boot crash on non-AMD systems
Fix boot crash that triggers if this driver is built into a kernel and run on non-AMD systems. AMD northbridges users call amd_cache_northbridges() and it returns a negative value to signal that we weren't able to cache/detect any northbridges on the system. At least, it should do so as all its callers expect it to do so. But it does return a negative value only when kmalloc() fails. Fix it to return -ENODEV if there are no NBs cached as otherwise, amd_nb users like amd64_edac, for example, which relies on it to know whether it should load or not, gets loaded on systems like Intel Xeons where it shouldn't. Reported-and-tested-by: Tony Battersby <> Signed-off-by: Borislav Petkov <> Cc: <> Cc: Linus Torvalds <> Cc: Peter Zijlstra <> Cc: Thomas Gleixner <> Link: Link: Signed-off-by: Ingo Molnar <>
Diffstat (limited to 'arch')
1 files changed, 2 insertions, 2 deletions
diff --git a/arch/x86/kernel/amd_nb.c b/arch/x86/kernel/amd_nb.c
index a147e67..e991d5c 100644
--- a/arch/x86/kernel/amd_nb.c
+++ b/arch/x86/kernel/amd_nb.c
@@ -71,8 +71,8 @@ int amd_cache_northbridges(void)
while ((misc = next_northbridge(misc, amd_nb_misc_ids)) != NULL)
- if (i == 0)
- return 0;
+ if (!i)
+ return -ENODEV;
nb = kzalloc(i * sizeof(struct amd_northbridge), GFP_KERNEL);
if (!nb)