Re: [PATCH v2 0/4] mm: Break COW for pinned pages during fork()

From: Leon Romanovsky
Date: Tue Sep 29 2020 - 07:02:26 EST


On Sun, Sep 27, 2020 at 12:35:59PM -0700, Linus Torvalds wrote:
> On Fri, Sep 25, 2020 at 3:26 PM Peter Xu <peterx@xxxxxxxxxx> wrote:
> >
> > This series is majorly inspired by the previous discussion on the list [1],
> > starting from the report from Jason on the rdma test failure.
>
> Ok, this is now in my git tree with the changes I outlined in the other email.
>
> > I tested it myself with fork() after vfio pinning a bunch of device pages,
>
> .. but _my_ only testing was to just add a nasty hack that said that
> all pages are pinned, and made fork() much slower, but hey, it at
> least tests the preallocation paths etc. And I'm not seeing any
> obvious failures due to taking that slow-path that is supposed to be a
> special case.
>
> Let's hope this closes the rdma issues.

Hi Linus,

We tested your tree upto commit "fb0155a09b02 Merge tag 'nfs-for-5.9-3' of
git://git.linux-nfs.org/projects/trondmy/linux-nfs" and our RDMA tests passed.

Thanks

>
> Linus