Messages in this thread | | | Date | Mon, 8 May 2006 11:34:25 +0300 | From | "Pekka Enberg" <> | Subject | Re: [PATCH] fs: fcntl_setlease defies lease_init assumptions |
| |
On 5/8/06, Linus Torvalds <torvalds@osdl.org> wrote: > > Ok, I was actually really surprised that we'd ever allow a non-slab page > > to be free'd as a slab or kmalloc allocation, without screaming very > > loudly indeed. That implies a lack of some pretty fundamental sanity > > checking by default in the slab layer (I suspect slab debugging turns it > > on, but even without it, that's just nasty). > > > > Can you see if this trivial patch at least causes a honking huge > > "kernel BUG" message to be triggered quickly?
On 5/8/06, Pekka Enberg <penberg@cs.helsinki.fi> wrote: > page_get_cache and page_get_slab are too late. You would need to do > the check in __cache_free; otherwise the stack pointer goes to per-CPU > caches and can be given back by kmalloc(). Adding PageSlab debugging > to __cache_free is probably too much of a performance hit, though.
Btw, CONFIG_DEBUG_SLAB should catch this case, see kfree_debugcheck() for details.
Pekka - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| |