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Date:   Sat, 25 Jun 2022 20:59:04 -0300
From:   Jason Gunthorpe <jgg@ziepe.ca>
To:     Peter Xu <peterx@redhat.com>
Cc:     kvm@vger.kernel.org, linux-kernel@vger.kernel.org,
        Paolo Bonzini <pbonzini@redhat.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        David Hildenbrand <david@redhat.com>,
        "Dr . David Alan Gilbert" <dgilbert@redhat.com>,
        Andrea Arcangeli <aarcange@redhat.com>,
        Linux MM Mailing List <linux-mm@kvack.org>,
        Sean Christopherson <seanjc@google.com>
Subject: Re: [PATCH 1/4] mm/gup: Add FOLL_INTERRUPTIBLE
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On Fri, Jun 24, 2022 at 09:23:04PM -0400, Peter Xu wrote:
> If to go back to the original question with a shorter answer: if the ioctl
> context that GUP upon a page that will never be with a uffd context, then
> it's probably not gonna help at all.. at least not before we use
> FAULT_FLAG_INTERRUPTIBLE outside uffd page fault handling.

I think I would be more interested in this if it could abort a swap
in, for instance. Doesn't this happen if it flows the interruptible
flag into the VMA's fault handler?

Jason