Message-ID: <a4ecf9eb-509a-84a6-8a9f-a3f5ea54ecac@suse.com>
Date:   Wed, 8 Mar 2023 10:41:51 -0800
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Subject: Re: [PATCH] scsi: core: Add BLIST_NO_ASK_VPD_SIZE for some VDASD
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To:     "Martin K. Petersen" <martin.petersen@oracle.com>
Cc:     Lee Duncan <leeman.duncan@gmail.com>,
        Linux regressions mailing list <regressions@lists.linux.dev>,
        "James E.J. Bottomley" <jejb@linux.ibm.com>,
        linux-scsi@vger.kernel.org, linux-kernel@vger.kernel.org,
        Martin Wilck <mwilck@suse.com>, Hannes Reinecke <hare@suse.de>,
        Srikar Dronamraju <srikar@linux.vnet.ibm.com>
References: <20220928181350.9948-1-leeman.duncan@gmail.com>
 <88927435-ae58-c24b-e7b7-b675985de433@leemhuis.info>
 <86D685F2-D411-460B-A09B-6BE942372F0A@gmail.com>
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 <yq1edq0jg2h.fsf@ca-mkp.ca.oracle.com>
From:   Lee Duncan <lduncan@suse.com>
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On 3/7/23 15:40, Martin K. Petersen wrote:
> 
> Lee,
> 
>> My worry is that this won't always work. Looking at the code, the
>> buffer sizes used for VPD pages include 8, 32, 64, and 252 bytes. I'm
>> not sure how reading 255 bytes into an 8-byte buffer would work.
> 
> In the scsi_get_vpd_buf() case we will allocate a 255 byte buffer since
> that's what scsi_get_vpd_size() returns for a VDASD.
> 
> And in the scsi_get_vpd_page() case, where a buffer already exists, we
> clamp the INQUIRY size to the minimum of scsi_get_vpd_size() and the
> buffer length provided by the caller.
> 

Please add my Reviewed-by tag then.

-- 
Lee