Re: [PATCH 0/2] make VM_SOFTDIRTY a sticky VMA flag

[Cyrill Gorcunov]

On Mon, Nov 17, 2025 at 07:57:30PM +0000, Lorenzo Stoakes wrote:
...
> > I recall correctly that initially, merging vma-s with different
> > VM_SORTDIRTY bit values was not allowed. It was a bit surprising that
> > this behavior was changed by Cyrill in 34228d473efe.  Cyrill was an
> > active CRIU contributor at the time, so we can't even blame anyone for
> > breaking CRIU :).
> 
> Well I think Cyrill is in the right here :) the problem described there -
> that of hitting the max_map_count simply due to failed VM_SOFTDIRTY merges
> - is very serious and clearly highlights the issue that arises from not
> merging these - that is VMA fragmentation.

Hi guys! Happen to miss this thread due to high message traffic, thanks
for CC'ing me ;) Yeah, disability to merge VMAs due to softdirty bit has
been a serious issue, so better criu to dump more (redundant) memory
than apps got broken. As to this patch series, I think it is good, thanks
a huge Lorenzo!

Acked-by: Cyrill Gorcunov <gorcunov@xxxxxxxxx>