lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
Open Source and information security mailing list archives
| ||
|
Date: Wed, 31 Oct 2007 21:46:02 +1100 From: Nick Piggin <nickpiggin@...oo.com.au> To: Peter Zijlstra <a.p.zijlstra@...llo.nl> Cc: Linus Torvalds <torvalds@...ux-foundation.org>, Andrew Morton <akpm@...ux-foundation.org>, linux-kernel@...r.kernel.org, linux-mm@...ck.org, netdev@...r.kernel.org, trond.myklebust@....uio.no Subject: Re: [PATCH 03/33] mm: slub: add knowledge of reserve pages On Wednesday 31 October 2007 21:42, Peter Zijlstra wrote: > On Wed, 2007-10-31 at 14:37 +1100, Nick Piggin wrote: > > On Wednesday 31 October 2007 03:04, Peter Zijlstra wrote: > > > Restrict objects from reserve slabs (ALLOC_NO_WATERMARKS) to allocation > > > contexts that are entitled to it. > > > > > > Care is taken to only touch the SLUB slow path. > > > > > > This is done to ensure reserve pages don't leak out and get consumed. > > > > I think this is generally a good idea (to prevent slab allocators > > from stealing reserve). However I naively think the implementation > > is a bit overengineered and thus has a few holes. > > > > Humour me, what was the problem with failing the slab allocation > > (actually, not fail but just call into the page allocator to do > > correct waiting / reclaim) in the slowpath if the process fails the > > watermark checks? > > Ah, we actually need slabs below the watermarks. Right, I'd still allow those guys to allocate slabs. Provided they have the right allocation context, right? > Its just that once I > allocated those slabs using __GFP_MEMALLOC/PF_MEMALLOC I don't want > allocation contexts that do not have rights to those pages to walk off > with objects. And I'd prevent these ones from doing so. Without keeping track of "reserve" pages, which doesn't feel too clean. - To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@...r.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Powered by blists - more mailing lists