Commit-ID: 1ead852dd88779eda12cb09cc894a03d9abfe1ec Gitweb: http://git.kernel.org/tip/1ead852dd88779eda12cb09cc894a03d9abfe1ec Author: Borislav Petkov <b...@suse.de> AuthorDate: Thu, 16 Jun 2016 19:13:49 +0200 Committer: Ingo Molnar <mi...@kernel.org> CommitDate: Fri, 1 Jul 2016 09:35:35 +0200
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 <to...@cybernetics.com> Signed-off-by: Borislav Petkov <b...@suse.de> Cc: <sta...@vger.kernel.org> Cc: Linus Torvalds <torva...@linux-foundation.org> Cc: Peter Zijlstra <pet...@infradead.org> Cc: Thomas Gleixner <t...@linutronix.de> Link: http://lkml.kernel.org/r/1466097230-5333-2-git-send-email...@alien8.de Link: https://lkml.kernel.org/r/5761beb0.9000...@cybernetics.com Signed-off-by: Ingo Molnar <mi...@kernel.org> --- arch/x86/kernel/amd_nb.c | 4 ++-- 1 file 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) i++; - if (i == 0) - return 0; + if (!i) + return -ENODEV; nb = kzalloc(i * sizeof(struct amd_northbridge), GFP_KERNEL); if (!nb)
