From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <mrochs@linux.vnet.ibm.com>
Received: from e39.co.us.ibm.com (e39.co.us.ibm.com [32.97.110.160])
 (using TLSv1 with cipher CAMELLIA256-SHA (256/256 bits))
 (No client certificate requested)
 by lists.ozlabs.org (Postfix) with ESMTPS id 7DBBD1A2B5F
 for <linuxppc-dev@lists.ozlabs.org>; Wed, 30 Sep 2015 05:40:16 +1000 (AEST)
Received: from localhost
 by e39.co.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only!
 Violators will be prosecuted
 for <linuxppc-dev@lists.ozlabs.org> from <mrochs@linux.vnet.ibm.com>;
 Tue, 29 Sep 2015 13:40:14 -0600
Received: from b03cxnp07028.gho.boulder.ibm.com
 (b03cxnp07028.gho.boulder.ibm.com [9.17.130.15])
 by d03dlp03.boulder.ibm.com (Postfix) with ESMTP id 6855119D8079
 for <linuxppc-dev@lists.ozlabs.org>; Tue, 29 Sep 2015 13:31:03 -0600 (MDT)
Received: from d03av05.boulder.ibm.com (d03av05.boulder.ibm.com [9.17.195.85])
 by b03cxnp07028.gho.boulder.ibm.com (8.14.9/8.14.9/NCO v10.0) with
 ESMTP id t8TJb3rk7209428
 for <linuxppc-dev@lists.ozlabs.org>; Tue, 29 Sep 2015 12:37:03 -0700
Received: from d03av05.boulder.ibm.com (localhost [127.0.0.1])
 by d03av05.boulder.ibm.com (8.14.4/8.14.4/NCO v10.0 AVout) with ESMTP id
 t8TJe99W018989
 for <linuxppc-dev@lists.ozlabs.org>; Tue, 29 Sep 2015 13:40:10 -0600
Content-Type: text/plain; charset=windows-1252
Mime-Version: 1.0 (Mac OS X Mail 8.2 \(2102\))
Subject: Re: [PATCH v4 32/32] cxlflash: Fix to avoid potential deadlock on EEH
From: "Matthew R. Ochs" <mrochs@linux.vnet.ibm.com>
In-Reply-To: <5609D03D.6010709@linux.vnet.ibm.com>
Date: Tue, 29 Sep 2015 14:40:09 -0500
Cc: linux-scsi@vger.kernel.org,
 James Bottomley <James.Bottomley@HansenPartnership.com>,
 "Nicholas A. Bellinger" <nab@linux-iscsi.org>,
 Ian Munsie <imunsie@au1.ibm.com>, Daniel Axtens <dja@ozlabs.au.ibm.com>,
 Andrew Donnellan <andrew.donnellan@au1.ibm.com>,
 Tomas Henzl <thenzl@redhat.com>, David Laight <David.Laight@ACULAB.COM>,
 Michael Neuling <mikey@neuling.org>, linuxppc-dev@lists.ozlabs.org,
 "Manoj N. Kumar" <manoj@linux.vnet.ibm.com>
Message-Id: <D7E92099-CCEE-4D1B-AF24-1397C8DCBDAD@linux.vnet.ibm.com>
References: <1443222593-8828-1-git-send-email-mrochs@linux.vnet.ibm.com>
 <1443223197-10153-1-git-send-email-mrochs@linux.vnet.ibm.com>
 <5609D03D.6010709@linux.vnet.ibm.com>
To: Brian King <brking@linux.vnet.ibm.com>
List-Id: Linux on PowerPC Developers Mail List <linuxppc-dev.lists.ozlabs.org>
List-Unsubscribe: <https://lists.ozlabs.org/options/linuxppc-dev>,
 <mailto:linuxppc-dev-request@lists.ozlabs.org?subject=unsubscribe>
List-Archive: <http://lists.ozlabs.org/pipermail/linuxppc-dev/>
List-Post: <mailto:linuxppc-dev@lists.ozlabs.org>
List-Help: <mailto:linuxppc-dev-request@lists.ozlabs.org?subject=help>
List-Subscribe: <https://lists.ozlabs.org/listinfo/linuxppc-dev>,
 <mailto:linuxppc-dev-request@lists.ozlabs.org?subject=subscribe>

> On Sep 28, 2015, at 6:41 PM, Brian King <brking@linux.vnet.ibm.com> =
wrote:
> On 09/25/2015 06:19 PM, Matthew R. Ochs wrote:
>> static int write_same16(struct scsi_device *sdev,
>> @@ -433,9 +451,20 @@ static int write_same16(struct scsi_device =
*sdev,
>> 		put_unaligned_be32(ws_limit < left ? ws_limit : left,
>> 				   &scsi_cmd[10]);
>>=20
>> +		/* Drop the ioctl read semahpore across lengthy call */
>> +		up_read(&cfg->ioctl_rwsem);
>> 		result =3D scsi_execute(sdev, scsi_cmd, DMA_TO_DEVICE, =
cmd_buf,
>> 				      CMD_BUFSIZE, sense_buf, to, =
CMD_RETRIES,
>> 				      0, NULL);
>> +		down_read(&cfg->ioctl_rwsem);
>> +		rc =3D check_state(cfg);
>> +		if (rc) {
>> +			dev_err(dev, "%s: Failed state! =
result=3D0x08%X\n",
>> +				__func__, result);
>> +			rc =3D -ENODEV;
>=20
> Since check_state only returns 0 or -ENODEV, this is a bit redundant, =
but not worth redoing the
> patch in my mind.

Agreed. This occurred to me the other day after submitting this patch =
when I was
reviewing the state locking code. Will look at revising in a future =
patch.

Thanks again for reviewing.