On Mon, 29 Jun 2009, Larry Finger wrote: > > Bug-Entry : http://bugzilla.kernel.org/show_bug.cgi?id=13319 > > Subject : Page allocation failures with b43 and p54usb > > Submitter : Larry Finger <Larry.Finger@xxxxxxxxxxxx> > > Date : 2009-04-29 21:01 (61 days old) > > References : http://marc.info/?l=linux-kernel&m=124103897101088&w=4 > > http://lkml.org/lkml/2009/6/7/136 > > Handled-By : Johannes Berg <johannes@xxxxxxxxxxxxxxxx> > > The cause of these failures has been determined. The wireless > subsystem frequently requests buffers of size 4096, but when SLUB > debugging is enabled and the debug info is added, the request becomes > of order 1 and memory becomes fragmented. > > A controversial "fix" in which SLUB debugging was disabled for > allocations where adding such debugging info would increase the order > was discussed and tried. With a quick look at the commit list for > Linus's tree, I don't see that such a patch is available, but I will > be corrected if I missed it. > I'd disagree with disabling slub debugging by default for caches where oo_order(s->min) increases as the result of using it. This particular page allocation failure is happening for, presumably, kmalloc-4096, and the system has 4K pages. Disabling debugging for that cache (and any of its aliases) implicitly will lead to errors going undiagnosed as a result. -- To unsubscribe from this list: send the line "unsubscribe kernel-testers" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
