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Date:   Tue, 29 Sep 2020 14:02:19 +0300
From:   Leon Romanovsky <leonro@nvidia.com>
To:     Linus Torvalds <torvalds@linux-foundation.org>
Cc:     Peter Xu <peterx@redhat.com>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Linux-MM <linux-mm@kvack.org>, Jason Gunthorpe <jgg@ziepe.ca>,
        John Hubbard <jhubbard@nvidia.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Christoph Hellwig <hch@lst.de>, Yang Shi <shy828301@gmail.com>,
        Oleg Nesterov <oleg@redhat.com>,
        Kirill Tkhai <ktkhai@virtuozzo.com>,
        Kirill Shutemov <kirill@shutemov.name>,
        Hugh Dickins <hughd@google.com>, Jann Horn <jannh@google.com>,
        Michal Hocko <mhocko@suse.com>, Jan Kara <jack@suse.cz>,
        Andrea Arcangeli <aarcange@redhat.com>
Subject: Re: [PATCH v2 0/4] mm: Break COW for pinned pages during fork()
Message-ID: <20200929110219.GF3094@unreal>
References: <20200925222600.6832-1-peterx@redhat.com>
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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@redhat.com> 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