From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 B009A160783; Mon, 27 May 2024 19:15:23 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1716837323; cv=none; b=Gf5mHjQv37D9GY3FxltwwpcQGA+UXcQZLH5RGrUq0QU2mTZfRmWs50E1N8NOBp2FJA4JmSVk5b+2FZ/d4Q+F1Wkvnp3Z5YHLEF7mxFrw21J/ILPQJYGAJGx2ibVGcNOpkZW4Iytpi1SApT8i4VhkPuZRyJFgdOm4B0pWD7jiWiA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1716837323; c=relaxed/simple; bh=Jo1V8WmUB5dNWmR2qabwCXi2YSIdP2On1Vw2oHqQYTs=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=OW1ET/0iKCKIi57Csc/Pgont6dVmyXBvKpbmX1G3ldj8KVBBhaixCwtFyGYhne3zd5Y2ZEi1gwZw3l3hQvE7PU1gs6ByO2yEwvu4FA+gupC+MVuP/7CK9ydaDo2jsBfLWbE7F0u6WoK0fRhtjc9HTLYPP/KcIM3PDQShn7QRkVE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=HTkG0k2e; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="HTkG0k2e" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 27AF3C2BBFC; Mon, 27 May 2024 19:15:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1716837323; bh=Jo1V8WmUB5dNWmR2qabwCXi2YSIdP2On1Vw2oHqQYTs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=HTkG0k2ebnNgcTxca3sskKwd4k3O+sOjzzhzvEe/ZZRgrxMv+uCoe1caW1Qm6PSfy i58Yf8GYvgZ4j7/RgPKoCOhakYiKaBBrrkBvULejKpd+7Yukip3xR3E5UUyQKprnPR NFbT15jXKsfkBHtKoC6HzOppwTzOnMcQaaHJaLmU= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Vishal Verma , Dan Williams , Alison Schofield , Dave Jiang , Andrew Morton , Sasha Levin Subject: [PATCH 6.9 395/427] dax/bus.c: use the right locking mode (read vs write) in size_show Date: Mon, 27 May 2024 20:57:22 +0200 Message-ID: <20240527185634.941981460@linuxfoundation.org> X-Mailer: git-send-email 2.45.1 In-Reply-To: <20240527185601.713589927@linuxfoundation.org> References: <20240527185601.713589927@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Vishal Verma [ Upstream commit 2acf04532d6d655d8c3b2ee4ddeb320107043086 ] In size_show(), the dax_dev_rwsem only needs a read lock, but was acquiring a write lock. Change it to down_read_interruptible() so it doesn't unnecessarily hold a write lock. Link: https://lkml.kernel.org/r/20240430-vv-dax_abi_fixes-v3-4-e3dcd755774c@intel.com Fixes: c05ae9d85b47 ("dax/bus.c: replace driver-core lock usage by a local rwsem") Signed-off-by: Vishal Verma Reviewed-by: Dan Williams Cc: Alison Schofield Cc: Dave Jiang Signed-off-by: Andrew Morton Signed-off-by: Sasha Levin --- drivers/dax/bus.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/dax/bus.c b/drivers/dax/bus.c index 0011a6e6a8f2a..f24b67c64d5ec 100644 --- a/drivers/dax/bus.c +++ b/drivers/dax/bus.c @@ -937,11 +937,11 @@ static ssize_t size_show(struct device *dev, unsigned long long size; int rc; - rc = down_write_killable(&dax_dev_rwsem); + rc = down_read_interruptible(&dax_dev_rwsem); if (rc) return rc; size = dev_dax_size(dev_dax); - up_write(&dax_dev_rwsem); + up_read(&dax_dev_rwsem); return sysfs_emit(buf, "%llu\n", size); } -- 2.43.0