[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [PATCH 2/2] tools/migration: Fix potential overflow in send_checkpoint_dirty_pfn_list()
- To: Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
- From: Jan Beulich <jbeulich@xxxxxxxx>
- Date: Tue, 6 Jul 2021 15:56:14 +0200
- Arc-authentication-results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=suse.com; dmarc=pass action=none header.from=suse.com; dkim=pass header.d=suse.com; arc=none
- Arc-message-signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=microsoft.com; s=arcselector9901; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=TDE0HYdVWJ38/VbrQibF2AdXhlrnFsiuqMUU5P04z8U=; b=FuQL1No8fF/3QhN9P/7KXTWffoYMXaKYFLMIxcF9i4tfwhhUC/mm0pab0OwKK9Je0mFrxEV2+9RUOAagow/MiLphgT2adtlXoG12tlRM8mfgK/tpQpPvPVre2v3hquJ0K3k/Msx+m0Owkt8Gv4Yt5Hx7lpQULPQsyZPLXKMWZTQqFN1SzN0nyw8t/iPkJXNSD1JeZHeKdKQ/NkfWAgFJ7qUajyBoHlM1T3FbAKmRGQLuiGQNU2ANmoDEY05T4AUF/58fgZZL18GgyDWO11IW2MucMeBk2w9z7S9UfR1W/fbd9XPoHR290519nQI1IOaXOkFzZ18mlp8dWzBtrAbc3w==
- Arc-seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=DruKaP5G3lvayFCCEtLHGDuBjx9OV60udGNaoONZU+XegvMJ4perVyPZUBIZcHUPZdLpd70T68ed+nOAMm23Pu7B+jvsAyZaqQeehMazrPOlgY+fK6ckwHKn2yTGEVJme8nyKSXU8F8Ytqzezsyq2h2WsGCF/qVZkowe0eNEQwCXn3bJk+U7loBkJmTWt4/MzIv5SEfPyAFCG0cXDQwsh7xIIZ3YmirZGX6TGXz02I0iobpnFHBQDBYckRsli/R2ViSeA65ZUV8/SH30ciVHdbcY7uZCMxmhCkwCe8wXcxOZR3eHcFOL03FM8pqCDeEpleFtt4Npc+w8AjlAGL09YQ==
- Authentication-results: aepfle.de; dkim=none (message not signed) header.d=none;aepfle.de; dmarc=none action=none header.from=suse.com;
- Cc: Xen-devel <xen-devel@xxxxxxxxxxxxxxxxxxxx>, Ian Jackson <iwj@xxxxxxxxxxxxxx>, Wei Liu <wl@xxxxxxx>, Juergen Gross <jgross@xxxxxxxx>, Olaf Hering <olaf@xxxxxxxxx>
- Delivery-date: Tue, 06 Jul 2021 13:56:34 +0000
- List-id: Xen developer discussion <xen-devel.lists.xenproject.org>
On 06.07.2021 15:19, Andrew Cooper wrote:
> On 06/07/2021 13:58, Olaf Hering wrote:
>> Am Tue, 6 Jul 2021 12:23:32 +0100
>> schrieb Andrew Cooper <andrew.cooper3@xxxxxxxxxx>:
>>
>>> + count = stats.dirty_count;
>> Is this accurate?
>
> The live loop relies on it, and it worked correctly the last time I
> tested it.
When still merely investigating in preparation of my recent series,
i.e. without having made changes yet except to add some logging, I
did observe "Bitmap contained more entries than expected..." a
couple of times, with "written" and "entries" typically apart by
just 1 (as determined by extra logging; to be honest I don't recall
if they were farther apart at any point). So the number is _not_
accurate in any event, and cannot be used for other than reporting
purposes (as also expressed elsewhere on this thread).
This also underlines that, unlike you did say in a reply to one of
my patches, this is only a "detail" message, not an error, because
migration happily went on and succeeded.
Jan
|