From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wm0-f71.google.com (mail-wm0-f71.google.com [74.125.82.71]) by kanga.kvack.org (Postfix) with ESMTP id C70126B025F for ; Tue, 8 Aug 2017 02:08:26 -0400 (EDT) Received: by mail-wm0-f71.google.com with SMTP id g71so3238620wmg.13 for ; Mon, 07 Aug 2017 23:08:26 -0700 (PDT) Received: from mx0a-001b2d01.pphosted.com (mx0b-001b2d01.pphosted.com. [148.163.158.5]) by mx.google.com with ESMTPS id r129si581144wma.40.2017.08.07.23.08.25 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 07 Aug 2017 23:08:25 -0700 (PDT) Received: from pps.filterd (m0098413.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.0.21/8.16.0.21) with SMTP id v7863phY060819 for ; Tue, 8 Aug 2017 02:08:24 -0400 Received: from e06smtp14.uk.ibm.com (e06smtp14.uk.ibm.com [195.75.94.110]) by mx0b-001b2d01.pphosted.com with ESMTP id 2c728rbf45-1 (version=TLSv1.2 cipher=AES256-SHA bits=256 verify=NOT) for ; Tue, 08 Aug 2017 02:08:23 -0400 Received: from localhost by e06smtp14.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Tue, 8 Aug 2017 07:08:22 +0100 Date: Tue, 8 Aug 2017 09:08:17 +0300 From: Mike Rapoport Subject: Re: [PATCH] userfaultfd: replace ENOSPC with ESRCH in case mm has gone during copy/zeropage References: <1502111545-32305-1-git-send-email-rppt@linux.vnet.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1502111545-32305-1-git-send-email-rppt@linux.vnet.ibm.com> Message-Id: <20170808060816.GA31648@rapoport-lnx> Sender: owner-linux-mm@kvack.org List-ID: To: Andrew Morton Cc: linux-mm , lkml , Andrea Arcangeli , "Dr. David Alan Gilbert" , Pavel Emelyanov , Mike Kravetz , Michal Hocko (adding Michal) On Mon, Aug 07, 2017 at 04:12:25PM +0300, Mike Rapoport wrote: > When the process exit races with outstanding mcopy_atomic, it would be > better to return ESRCH error. When such race occurs the process and it's mm > are going away and returning "no such process" to the uffd monitor seems > better fit than ENOSPC. > > Suggested-by: Michal Hocko > Cc: Andrea Arcangeli > Cc: "Dr. David Alan Gilbert" > Cc: Pavel Emelyanov > Cc: Mike Kravetz > Signed-off-by: Mike Rapoport > --- > The man-pages update is ready and I'll send it out once the patch is > merged. > > fs/userfaultfd.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/fs/userfaultfd.c b/fs/userfaultfd.c > index 06ea26b8c996..b0d5897bc4e6 100644 > --- a/fs/userfaultfd.c > +++ b/fs/userfaultfd.c > @@ -1600,7 +1600,7 @@ static int userfaultfd_copy(struct userfaultfd_ctx *ctx, > uffdio_copy.len); > mmput(ctx->mm); > } else { > - return -ENOSPC; > + return -ESRCH; > } > if (unlikely(put_user(ret, &user_uffdio_copy->copy))) > return -EFAULT; > @@ -1647,7 +1647,7 @@ static int userfaultfd_zeropage(struct userfaultfd_ctx *ctx, > uffdio_zeropage.range.len); > mmput(ctx->mm); > } else { > - return -ENOSPC; > + return -ESRCH; > } > if (unlikely(put_user(ret, &user_uffdio_zeropage->zeropage))) > return -EFAULT; > -- > 2.7.4 > -- Sincerely yours, Mike. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org