From patchwork Thu Aug 1 05:42:34 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Shin'ichiro Kawasaki X-Patchwork-Id: 13749601 Received: from esa6.hgst.iphmx.com (esa6.hgst.iphmx.com [216.71.154.45]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id AEE9914C58E; Thu, 1 Aug 2024 05:42:37 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=216.71.154.45 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1722490959; cv=none; b=DyZSeASbIsuiTNz0qyJVH8IZSabQUxVVOyJvnqKsKdQt/1tlScGoUoYdwvGmaQ1gl8YQpBhpPU7jSGKEIpa7pO0DnML3k18D5M/Acvj5AjdZFbh+r8q16lhrMzt53ZkiLSnff0oSUm/dGSU+DfJ12ebLJtBgzbyhX1vps67zCOw= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1722490959; c=relaxed/simple; bh=V8Fc8yJKmYW061eVlMN3P3crU7VpmpmQ9s2+yRXA3xA=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=mv5NTVb9jAKABfLmoT4l6vcsx6UTNPqRc1zCAhsI3LTR2GV7NzKAHT9Y2IFDV4dhzjc6izebkX0dVijhDXZ07tJC+wLXD7Yqw7dneGRFNk9aqLiSLbdtSgvnR6ePy5wlvKM+ARqAommCXJprDn3bTSw4baGb95TOSQZfXTBHJhA= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=wdc.com; spf=pass smtp.mailfrom=wdc.com; dkim=pass (2048-bit key) header.d=wdc.com header.i=@wdc.com header.b=MlBbtIqe; arc=none smtp.client-ip=216.71.154.45 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=wdc.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=wdc.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=wdc.com header.i=@wdc.com header.b="MlBbtIqe" DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=wdc.com; i=@wdc.com; q=dns/txt; s=dkim.wdc.com; t=1722490957; x=1754026957; h=from:to:cc:subject:date:message-id:mime-version: content-transfer-encoding; bh=V8Fc8yJKmYW061eVlMN3P3crU7VpmpmQ9s2+yRXA3xA=; b=MlBbtIqedk8RUdRvc/QXNZzJbrJa7trykUuOFVyrbs7ELrtoZOEDIA/L nRl8cPJ07QZeKapv8b766dllVXCQQyQPwoU4owAWalTemssXKBoIq0MjI /K+b4C3UOw/XSLhKM3L5WtDO8Pa97HlSKgsiNIa4uw3i9U4ycZmgY8iwW GQPMoOZ0VBDTBMEfa3sQcHHnaKZBqkjsresrccKFqG6ajHLuQ1GbOzdlb CBGQCpjnHL1rZJ3p0jyoJ8+djr8NnEOlZZKnc/pZsx2GZcLilpvJJE+nE bu3kGGBrWJPIEXGJKyR68R995oZ273VB9r3+fLxSwRjrDPJxiqF/L8KWn w==; X-CSE-ConnectionGUID: u7IJ47SEQy2JevqLbkHPeQ== X-CSE-MsgGUID: EF5Eo5+RSjedIJkxpP68kw== X-IronPort-AV: E=Sophos;i="6.09,253,1716220800"; d="scan'208";a="23250163" Received: from uls-op-cesaip02.wdc.com (HELO uls-op-cesaep02.wdc.com) ([199.255.45.15]) by ob1.hgst.iphmx.com with ESMTP; 01 Aug 2024 13:42:36 +0800 IronPort-SDR: 66ab1259_dzX/Gz12i/mYUHg8eYPFZQVp+f5WrkQSnxXDpmTK/CqrvZe kb7T4yb1o88lB/Rg2peFbyNLxAuQwGPQN2gzBLQ== Received: from uls-op-cesaip02.wdc.com ([10.248.3.37]) by uls-op-cesaep02.wdc.com with ESMTP/TLS/ECDHE-RSA-AES128-GCM-SHA256; 31 Jul 2024 21:43:06 -0700 WDCIronportException: Internal Received: from unknown (HELO shindev.ssa.fujisawa.hgst.com) ([10.149.66.30]) by uls-op-cesaip02.wdc.com with ESMTP; 31 Jul 2024 22:42:36 -0700 From: Shin'ichiro Kawasaki To: linux-scsi@vger.kernel.org, linux-block@vger.kernel.org Cc: Christoph Hellwig , Coelho, Luciano , Saarinen, Jani , Shin'ichiro Kawasaki Subject: [PATCH] scsi: sd: Move sd_read_cpr() out of the q->limits_lock region Date: Thu, 1 Aug 2024 14:42:34 +0900 Message-ID: <20240801054234.540532-1-shinichiro.kawasaki@wdc.com> X-Mailer: git-send-email 2.45.2 Precedence: bulk X-Mailing-List: linux-block@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Commit 804e498e0496 ("sd: convert to the atomic queue limits API") introduced pairs of function calls to queue_limits_start_update() and queue_limits_commit_update(). These two functions lock and unlock q->limits_lock. In sd_revalidate_disk(), sd_read_cpr() is called after queue_limits_start_update() call and before queue_limits_commit_update() call. sd_read_cpr() locks q->sysfs_dir_lock and &q->sysfs_lock. Then new lock dependencies were created between q->limits_lock, q->sysfs_dir_lock and q->sysfs_lock, as follows: sd_revalidate_disk queue_limits_start_update mutex_lock(&q->limits_lock) sd_read_cpr disk_set_independent_access_ranges mutex_lock(&q->sysfs_dir_lock) mutex_lock(&q->sysfs_lock) mutex_unlock(&q->sysfs_lock) mutex_unlock(&q->sysfs_dir_lock) queue_limits_commit_update mutex_unlock(&q->limits_lock) However, the three locks already had reversed dependencies in other places. Then the new dependencies triggered the lockdep WARN "possible circular locking dependency detected" [1]. This WARN was observed by running the blktests test case srp/002. To avoid the WARN, move the sd_read_cpr() call in sd_revalidate_disk() after the queue_limits_commit_update() call. In other words, move the sd_read_cpr() call out of the q->limits_lock region. [1] https://lore.kernel.org/linux-scsi/vlmv53ni3ltwxplig5qnw4xsl2h6ccxijfbqzekx76vxoim5a5@dekv7q3es3tx/ Fixes: 804e498e0496 ("sd: convert to the atomic queue limits API") Signed-off-by: Shin'ichiro Kawasaki Tested-by: Luca Coelho Reviewed-by: Damien Le Moal Reviewed-by: Christoph Hellwig Reviewed-by: Bart Van Assche --- drivers/scsi/sd.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c index adeaa8ab9951..08cbe3815006 100644 --- a/drivers/scsi/sd.c +++ b/drivers/scsi/sd.c @@ -3753,7 +3753,6 @@ static int sd_revalidate_disk(struct gendisk *disk) sd_read_block_limits_ext(sdkp); sd_read_block_characteristics(sdkp, &lim); sd_zbc_read_zones(sdkp, &lim, buffer); - sd_read_cpr(sdkp); } sd_print_capacity(sdkp, old_capacity); @@ -3808,6 +3807,14 @@ static int sd_revalidate_disk(struct gendisk *disk) if (err) return err; + /* + * Query concurrent positioning ranges after + * queue_limits_commit_update() unlocked q->limits_lock to avoid + * deadlock with q->sysfs_dir_lock and q->sysfs_lock. + */ + if (sdkp->media_present && scsi_device_supports_vpd(sdp)) + sd_read_cpr(sdkp); + /* * For a zoned drive, revalidating the zones can be done only once * the gendisk capacity is set. So if this fails, set back the gendisk