linux-kernel - Re: [RFC PATCH v2 00/18] scsi: scsi_error: Introduce new error handle mechanism

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <8057d66f-4f0b-4f03-8401-51c85ac27f41@oracle.com>
Date:   Mon, 25 Sep 2023 11:52:26 -0500
From:   Mike Christie <michael.christie@...cle.com>
To:     Wenchao Hao <haowenchao2@...wei.com>,
        "James E . J . Bottomley" <jejb@...ux.ibm.com>,
        "Martin K . Petersen" <martin.petersen@...cle.com>,
        linux-scsi@...r.kernel.org
Cc:     Hannes Reinecke <hare@...e.de>, linux-kernel@...r.kernel.org,
        louhongxiang@...wei.com, lixiaokeng@...wei.com
Subject: Re: [RFC PATCH v2 00/18] scsi: scsi_error: Introduce new error handle
 mechanism

On 9/14/23 1:20 AM, Wenchao Hao wrote:
> On 2023/9/1 17:41, Wenchao Hao wrote:
>> It's unbearable for systems with large scale scsi devices share HBAs to
>> block all devices' IOs when handle error commands, we need a new error
>> handle mechanism to address this issue.
>>
>> I consulted about this issue a year ago, the discuss link can be found in
>> refenence. Hannes replied about why we have to block the SCSI host
>> then perform error recovery kindly. I think it's unnecessary to block
>> SCSI host for all drivers and can try a small level recovery(LUN based for
>> example) first to avoid block the SCSI host.
>>
>> The new error handle mechanism introduced in this patchset has been
>> developed and tested with out self developed hardware since one year
>> ago, now we want this mechanism can be used by more drivers.
>>
>> Drivers can decide if using the new error handle mechanism and how to
>> handle error commands when scsi_device are scanned,the new mechanism
>> makes SCSI error handle more flexible.
>>
>> SCSI error recovery strategy after blocking host's IO is mainly
>> following steps:
>>
>> - LUN reset
>> - Target reset
>> - Bus reset
>> - Host reset
>>
> 
> Mike gave some suggestions and I found a bug in fallback logic, I would
> address these and resend in next few days.

Please wait to resend. I'm still reviewing the patches. When I commented
last time I just did a quick look over to get an idea for the design and
what your goals were.