Messages in this thread | | | Subject | Re: 2.6.22-rc4-mm1 | From | Peter Zijlstra <> | Date | Wed, 06 Jun 2007 21:27:55 +0200 |
| |
On Wed, 2007-06-06 at 19:06 +0200, Peter Zijlstra wrote: > On Wed, 2007-06-06 at 09:35 -0700, William Lee Irwin III wrote: > > On Wed, Jun 06, 2007 at 05:26:49PM +0100, Mel Gorman wrote: > > > I do not believe this is Nick's problem. I encountered the same issue and > > > the bisect ended up here; > > > # BISECT HERE > > > mm-variable-length-argument-support.patch > > > mm-variable-length-argument-support-fix.patch > > > # BISECT BAD > > > Reverting those two patches boots ok on my standalone x86 laptop. > > > Patch authors cc'd. I have not read the patches yet to see what might > > > be the problem. > > > > I found this a while ago and peterz already has a tentative fix for it at > > http://programming.kicks-ass.net/kernel-patches/max_arg_pages/move_anon_vma.patch > > I'm sure he himself will chime in with more/better code when he returns. > > Ah, yes indeed. We were discussing wether it would be better to update > page->index (as this patch does) or not change vma->vm_pgoff. Bill > argued that the latter would be safe, it would just limit the merge > capabilities of the anon vma (and the stack rarely, if ever, merges > anyway). > > I myself an not quite sure on the effects of ->vm_pgoff of anon vmas > yet.
Ok, from what I can make of it, nobody relies on the value of vma->vm_pgoff for anon vmas as long as the following invariant is kept:
vaddr = vma->vm_start + (page->index - vma->vm_pgoff)*PAGE_SIZE
So the proper thing to do is not change vm_pgoff.
- 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/
| |