rmap: always add new vmas at the end
in [Kernel]
|
Prev: [PATCH] PCI: Default PCIe ASPM control to on and require !EMBEDDED to disable
Next: Xen-SWIOTBL v0.8.3 used for Xen PCI pass through for PV guests.
From: Andrew Morton on 22 Jun 2010 17:10 On Mon, 21 Jun 2010 16:33:49 -0400 Rik van Riel <riel(a)redhat.com> wrote: > From: Andrea Arcangeli <aarcange(a)redhat.com> > Subject: always add new vmas at the end > > Make sure to always add new VMAs at the end of the list. This > is important so rmap_walk does not miss a VMA that was created > during the rmap_walk. > > The old code got this right most of the time due to luck, but > was buggy when anon_vma_prepare reused a mergeable anon_vma. > > Signed-off-by: Andrea Arcangeli <aarcange(a)redhat.com> > Signed-off-by: Rik van Riel <riel(a)redhat.com> > --- > > diff --git a/mm/rmap.c b/mm/rmap.c > --- a/mm/rmap.c > +++ b/mm/rmap.c > @@ -149,7 +149,7 @@ int anon_vma_prepare(struct vm_area_stru > avc->anon_vma = anon_vma; > avc->vma = vma; > list_add(&avc->same_vma, &vma->anon_vma_chain); > - list_add(&avc->same_anon_vma, &anon_vma->head); > + list_add_tail(&avc->same_anon_vma, &anon_vma->head); > allocated = NULL; > avc = NULL; > } Should this go into 2.6.35? -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo(a)vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
From: Andrea Arcangeli on 22 Jun 2010 17:20
On Tue, Jun 22, 2010 at 02:08:22PM -0700, Andrew Morton wrote: > On Mon, 21 Jun 2010 16:33:49 -0400 > Rik van Riel <riel(a)redhat.com> wrote: > > > From: Andrea Arcangeli <aarcange(a)redhat.com> > > Subject: always add new vmas at the end > > > > Make sure to always add new VMAs at the end of the list. This > > is important so rmap_walk does not miss a VMA that was created > > during the rmap_walk. > > > > The old code got this right most of the time due to luck, but > > was buggy when anon_vma_prepare reused a mergeable anon_vma. > > > > Signed-off-by: Andrea Arcangeli <aarcange(a)redhat.com> > > Signed-off-by: Rik van Riel <riel(a)redhat.com> > > --- > > > > diff --git a/mm/rmap.c b/mm/rmap.c > > --- a/mm/rmap.c > > +++ b/mm/rmap.c > > @@ -149,7 +149,7 @@ int anon_vma_prepare(struct vm_area_stru > > avc->anon_vma = anon_vma; > > avc->vma = vma; > > list_add(&avc->same_vma, &vma->anon_vma_chain); > > - list_add(&avc->same_anon_vma, &anon_vma->head); > > + list_add_tail(&avc->same_anon_vma, &anon_vma->head); > > allocated = NULL; > > avc = NULL; > > } > > Should this go into 2.6.35? Well migrate got broken anyway in 2.6.34, so until the whole root-anon-vma patchqueue is merged, it's not going to provide a safe migrate anyway and it can as well wait with the rest. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo(a)vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/ |