From: Mike Kravetz <mike.kravetz@oracle.com>
To: Dmitry Vyukov <dvyukov@google.com>
Cc: Andrew Morton <akpm@linux-foundation.org>,
Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>,
Hillf Danton <hillf.zj@alibaba-inc.com>,
David Rientjes <rientjes@google.com>,
"Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>,
Dave Hansen <dave.hansen@linux.intel.com>,
"linux-mm@kvack.org" <linux-mm@kvack.org>,
LKML <linux-kernel@vger.kernel.org>,
Hugh Dickins <hughd@google.com>, Greg Thelen <gthelen@google.com>,
syzkaller <syzkaller@googlegroups.com>,
Kostya Serebryany <kcc@google.com>,
Alexander Potapenko <glider@google.com>,
Sasha Levin <sasha.levin@oracle.com>,
Eric Dumazet <edumazet@google.com>
Subject: Re: memory leak in alloc_huge_page
Date: Tue, 1 Dec 2015 16:54:21 -0800 [thread overview]
Message-ID: <565E413D.8050608@oracle.com> (raw)
In-Reply-To: <CACT4Y+Zsw23LiBhakWUFfO88OuuHsV588g3T9UPfMKxRBLojGQ@mail.gmail.com>
On 12/01/2015 11:45 AM, Dmitry Vyukov wrote:
> On Tue, Dec 1, 2015 at 7:52 PM, Mike Kravetz <mike.kravetz@oracle.com> wrote:
>> On 12/01/2015 06:04 AM, Dmitry Vyukov wrote:
>>> There seems to be another leak if nrg is not NULL on this path, but
>>> it's not what happens in my case since the WARNING does not fire.
>>
>> If nrg is not NULL, then it was added to the resv map and 'should' be
>> free'ed when the map is free'ed. This is not optimal, but I do not
>> think it would lead to a leak. I'll take a close look at this code
>> with an emphasis on the leak you discovered.
>
>
> Hi Mike,
>
> Note that it's not just a leak report, it is an actual leak. You
> should be able to reproduce it.
>
OK, finally found the bug which is in region_del(). It does not correctly
handle a "placeholder" region descriptor that is left after an aborted
operation when the start of the region to be deleted is for the same page.
I will have a patch shortly, after some testing.
--
Mike Kravetz
--
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: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>
WARNING: multiple messages have this Message-ID (diff)
From: Mike Kravetz <mike.kravetz@oracle.com>
To: Dmitry Vyukov <dvyukov@google.com>
Cc: Andrew Morton <akpm@linux-foundation.org>,
Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>,
Hillf Danton <hillf.zj@alibaba-inc.com>,
David Rientjes <rientjes@google.com>,
"Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>,
Dave Hansen <dave.hansen@linux.intel.com>,
"linux-mm@kvack.org" <linux-mm@kvack.org>,
LKML <linux-kernel@vger.kernel.org>,
Hugh Dickins <hughd@google.com>, Greg Thelen <gthelen@google.com>,
syzkaller <syzkaller@googlegroups.com>,
Kostya Serebryany <kcc@google.com>,
Alexander Potapenko <glider@google.com>,
Sasha Levin <sasha.levin@oracle.com>,
Eric Dumazet <edumazet@google.com>
Subject: Re: memory leak in alloc_huge_page
Date: Tue, 1 Dec 2015 16:54:21 -0800 [thread overview]
Message-ID: <565E413D.8050608@oracle.com> (raw)
In-Reply-To: <CACT4Y+Zsw23LiBhakWUFfO88OuuHsV588g3T9UPfMKxRBLojGQ@mail.gmail.com>
On 12/01/2015 11:45 AM, Dmitry Vyukov wrote:
> On Tue, Dec 1, 2015 at 7:52 PM, Mike Kravetz <mike.kravetz@oracle.com> wrote:
>> On 12/01/2015 06:04 AM, Dmitry Vyukov wrote:
>>> There seems to be another leak if nrg is not NULL on this path, but
>>> it's not what happens in my case since the WARNING does not fire.
>>
>> If nrg is not NULL, then it was added to the resv map and 'should' be
>> free'ed when the map is free'ed. This is not optimal, but I do not
>> think it would lead to a leak. I'll take a close look at this code
>> with an emphasis on the leak you discovered.
>
>
> Hi Mike,
>
> Note that it's not just a leak report, it is an actual leak. You
> should be able to reproduce it.
>
OK, finally found the bug which is in region_del(). It does not correctly
handle a "placeholder" region descriptor that is left after an aborted
operation when the start of the region to be deleted is for the same page.
I will have a patch shortly, after some testing.
--
Mike Kravetz
next prev parent reply other threads:[~2015-12-02 0:54 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-12-01 14:04 memory leak in alloc_huge_page Dmitry Vyukov
2015-12-01 14:04 ` Dmitry Vyukov
2015-12-01 18:52 ` Mike Kravetz
2015-12-01 18:52 ` Mike Kravetz
2015-12-01 19:45 ` Dmitry Vyukov
2015-12-01 19:45 ` Dmitry Vyukov
2015-12-02 0:54 ` Mike Kravetz [this message]
2015-12-02 0:54 ` Mike Kravetz
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=565E413D.8050608@oracle.com \
--to=mike.kravetz@oracle.com \
--cc=akpm@linux-foundation.org \
--cc=dave.hansen@linux.intel.com \
--cc=dvyukov@google.com \
--cc=edumazet@google.com \
--cc=glider@google.com \
--cc=gthelen@google.com \
--cc=hillf.zj@alibaba-inc.com \
--cc=hughd@google.com \
--cc=kcc@google.com \
--cc=kirill.shutemov@linux.intel.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=n-horiguchi@ah.jp.nec.com \
--cc=rientjes@google.com \
--cc=sasha.levin@oracle.com \
--cc=syzkaller@googlegroups.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.