Messages in this thread | | | From | Michael Ellerman <> | Subject | Re: [linux-next][Oops] CPU toggle resulted in kernel crash | Date | Fri, 06 Oct 2017 09:53:36 +1100 |
| |
Kees Cook <keescook@chromium.org> writes:
> On Thu, Oct 5, 2017 at 10:21 AM, Abdul Haleem > <abdhalee@linux.vnet.ibm.com> wrote: >> Hi, >> >> CPU off on in a loop for single cpu results in kernel panic for >> 4.14.0-rc2-next-20170929 >> >> Machine: Power 8 PowerVM LPAR >> Kernel: 4.14.0-rc2-next-20170929 >> gcc: 5.1.1 >> config : attached >> >> Steps to recreate: >> ----------------- >> The issue is not reproducible all the time. >> >> The trace occurred when CPU toggle operation for cpu14 in a loop for 10 >> iterations. >> >> the Faulting instruction address: 0xc00000000035465c >> maps to: >> >> 0xc00000000035465c is in deactivate_slab (mm/slub.c:261). >> 256 >> 257 /* Returns the freelist pointer recorded at location ptr_addr. */ >> 258 static inline void *freelist_dereference(const struct kmem_cache *s, >> 259 void *ptr_addr) >> 260 { >> 261 return freelist_ptr(s, (void *)*(unsigned long *)(ptr_addr), >> 262 (unsigned long)ptr_addr); >> 263 } >> 264 >> 265 static inline void *get_freepointer(struct kmem_cache *s, void *object) > > This looks like slub cache corruption (a NULL pointer dereference for > the heap freelist).
Abdul, try turning on CONFIG_SLUB_DEBUG, and booting with slub_debug=FZP on the command line.
cheers
| |