linux-kernel - Re: [PATCH v2 1/4] scsi: scsi_dh_alua: allow I/O in target port unavailable and standby states

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 for Android: free password hash cracker in your pocket

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

Message-Id: <224d8cd3-478c-2440-3479-0119885575cf@linux.vnet.ibm.com>
Date:   Tue, 11 Jul 2017 12:32:15 -0300
From:   Mauricio Faria de Oliveira <mauricfo@...ux.vnet.ibm.com>
To:     Hannes Reinecke <hare@...e.de>
Cc:     jejb@...ux.vnet.ibm.com, martin.petersen@...cle.com,
        bart.vanassche@...disk.com, linux-scsi@...r.kernel.org,
        linux-kernel@...r.kernel.org
Subject: Re: [PATCH v2 1/4] scsi: scsi_dh_alua: allow I/O in target port
 unavailable and standby states

On 07/11/2017 06:18 AM, Hannes Reinecke wrote:
> NACK.
> 
> The whole_point_  of having device handlers is to_avoid_  I/O errors
> during booting.
> 
> And the ALUA checker is prepared to handle this situation properly.
> The directio checker of course doesn't know about this, but then no-one
> expected the directio checker to work with ALUA.

I lacked that more holistic understanding. Thanks for explaining.

Now, for the sake of logging/debugging...

Any problem with patches 2 and 4?

Also, it seems the Unavailable/Standby states would not be logged
without a recheck from alua_check_sense(), since the only callers
of alua_rtpg_queue() are alua_activate() and alua_check[_sense]()
[the call from alua_check_vpd() is only in the initialization path].

Isn't there a point in scheduling a recheck once those conditions
are found in alua_check_sense() to get them logged? - since valid
path checkers won't go through that function.

(and it occurred to me that the state-change check of patch 3 can
be done there, simpler.)

cheers,

-- 
Mauricio Faria de Oliveira
IBM Linux Technology Center