On Fri, 7 Oct 2011 18:27:06 +0200 Arnd Bergmann arnd@arndb.de wrote:
On Thursday 06 October 2011, Marek Szyprowski wrote:
Once again I decided to post an updated version of the Contiguous Memory Allocator patches.
This version provides mainly a bugfix for a very rare issue that might have changed migration type of the CMA page blocks resulting in dropping CMA features from the affected page block and causing memory allocation to fail. Also the issue reported by Dave Hansen has been fixed.
This version also introduces basic support for x86 architecture, what allows wide testing on KVM/QEMU emulators and all common x86 boxes. I hope this will result in wider testing, comments and easier merging to mainline.
Hi Marek,
I think we need to finally get this into linux-next now, to get some broader testing. Having the x86 patch definitely helps here becauses it potentially exposes the code to many more testers.
IMHO it would be good to merge the entire series into 3.2, since the ARM portion fixes an important bug (double mapping of memory ranges with conflicting attributes) that we've lived with for far too long, but it really depends on how everyone sees the risk for regressions here. If something breaks in unfixable ways before the 3.2 release, we can always revert the patches and have another try later.
It's also not clear how we should merge it. Ideally the first bunch would go through linux-mm, and the architecture specific patches through the respective architecture trees, but there is an obvious inderdependency between these sets.
Russell, Andrew, are you both comfortable with putting the entire set into linux-mm to solve this? Do you see this as 3.2 or rather as 3.3 material?
Russell's going to hate me, but...
I do know that he had substantial objections to at least earlier versions of this, and he is a guy who knows of what he speaks.
So I would want to get a nod from rmk on this work before proceeding. If that nod isn't available then let's please identify the issues and see what we can do about them.