From: Hugh Dickins <hughd@google.com>
To: Andrea Arcangeli <aarcange@redhat.com>
Cc: linux-mm@kvack.org, Marcelo Tosatti <mtosatti@redhat.com>,
Rik van Riel <riel@redhat.com>
Subject: Re: [PATCH] fix swapin race condition
Date: Fri, 9 Jul 2010 14:19:12 -0700 [thread overview]
Message-ID: <AANLkTilUUDMp1U46M3GbGLtaMIkGaTtx0hBrnmRfSkJ4@mail.gmail.com> (raw)
In-Reply-To: <alpine.DEB.1.00.1007091242430.8201@tigran.mtv.corp.google.com>
On Fri, Jul 9, 2010 at 1:32 PM, Hugh Dickins <hughd@google.com> wrote:
>
> There's a related bug of mine lurking here, only realized in looking
> through this, which you might want to fix at the same time: I should
> have moved the PageUptodate check from after the pte_same check to
> before the ksm_might_need_to_copy, shouldn't I? As it stands, we
> might copy junk from an invalid !Uptodate page into a clean new page.
Actually, not so, forget it: though it does look worrying, if the swap
page read had failed, leaving the page !Uptodate, then it would not
have been inserted into any address space in the first place,
page->mapping would remain unset, and ksm_might_need_to_copy() would
have no reason to copy it.
Hugh
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next prev parent reply other threads:[~2010-07-09 21:19 UTC|newest]
Thread overview: 19+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-07-09 0:23 Andrea Arcangeli
2010-07-09 20:32 ` Hugh Dickins
2010-07-09 21:19 ` Hugh Dickins [this message]
2010-07-09 22:02 ` Rik van Riel
2010-07-13 1:08 ` Andrea Arcangeli
2010-07-13 21:30 ` Hugh Dickins
2010-09-03 15:39 Andrea Arcangeli
2010-09-03 20:02 ` Andrew Morton
2010-09-04 12:29 ` Andrea Arcangeli
2010-09-03 23:57 ` Rik van Riel
2010-09-06 2:35 ` Hugh Dickins
2010-09-15 23:02 ` Hugh Dickins
2010-09-15 23:42 ` Andrea Arcangeli
2010-09-16 0:10 ` Hugh Dickins
2010-09-16 21:03 ` Andrea Arcangeli
2010-09-16 21:08 ` Andrea Arcangeli
2010-09-17 2:31 ` Hugh Dickins
2010-09-18 13:19 ` Andrea Arcangeli
2010-09-20 2:35 ` Hugh Dickins
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