From patchwork Thu Aug 1 08:22:57 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Luca Coelho X-Patchwork-Id: 13749966 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id D716AC3DA4A for ; Thu, 1 Aug 2024 08:23:10 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 8287510E35B; Thu, 1 Aug 2024 08:23:10 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; unprotected) header.d=intel.com header.i=@intel.com header.b="g7/93aiy"; dkim-atps=neutral Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.16]) by gabe.freedesktop.org (Postfix) with ESMTPS id 8D74410E35B for ; Thu, 1 Aug 2024 08:23:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1722500589; x=1754036589; h=from:to:cc:subject:date:message-id:mime-version: content-transfer-encoding; bh=KvkUICcLnnVVgActzEeCFcBHNKty6prgKrWfLQvF1qI=; b=g7/93aiyLjz0VQsxzl4P1xvRbHndeIvgTfUQsYtIaFkii9zIAfZ2d7iS 6JiszFc8t+uqpSG/DCnGWJkTA+WWUtUhCcf2DuhD/m7OPiTqt23grbG4h Jl9ivtVbunvxgcBV6IhbYchUr/7e/Q31X0cJaoHL82+Qk+qzACqR1LQAv xKCrQ8zNeSUJ/m7CMUnZ3sucww8kcSMTHebNISUpbhp35qe15KogxG3SM RrS5Y626G0nPIehbF9Ai++3LONMGcPpqBQovEpFHouLyZLJEDgiyd9zKD vvxzsenLuTkCoqKBw2ETHhwtcB4kMgqeTmaQBRFd9jujhtCr2P0k7hv3M Q==; X-CSE-ConnectionGUID: IgaaDF6KSLqrVcx1gbhLFw== X-CSE-MsgGUID: 2y6soDT+Rqqg9i2GlEqxww== X-IronPort-AV: E=McAfee;i="6700,10204,11150"; a="12824716" X-IronPort-AV: E=Sophos;i="6.09,254,1716274800"; d="scan'208";a="12824716" Received: from orviesa007.jf.intel.com ([10.64.159.147]) by fmvoesa110.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 01 Aug 2024 01:23:09 -0700 X-CSE-ConnectionGUID: cctjWcggTzmUFXiX1iq32A== X-CSE-MsgGUID: b/LEP180T9+IpV445q0lHg== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.09,254,1716274800"; d="scan'208";a="55549740" Received: from dhhellew-desk2.ger.corp.intel.com.ger.corp.intel.com (HELO lcoelho-mobl1.ger.corp.intel.com) ([10.245.244.200]) by orviesa007-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 01 Aug 2024 01:23:07 -0700 From: Luca Coelho To: intel-gfx@lists.freedesktop.org Cc: jani.saarinen@intel.com Subject: [core-for-CI PATCH] scsi: sd: Move sd_read_cpr() out of the q->limits_lock region Date: Thu, 1 Aug 2024 11:22:57 +0300 Message-Id: <20240801082257.506006-1-luciano.coelho@intel.com> X-Mailer: git-send-email 2.39.2 MIME-Version: 1.0 X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Intel graphics driver community testing & development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" From: Shin'ichiro Kawasaki 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 Signed-off-by: Luca Coelho Acked-by: Jani Nikula --- 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