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 164336BFCE; Wed, 13 Mar 2024 17:02:20 +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=1710349341; cv=none; b=qamypcGOMtjJ4TOmYlz2L11agUdM1dT69swTUYeqpklBSmpjy43s9EOs8GBCC10/Dur4sXprEfReJv5oQIqUXGHZ0mcEs/gkII481UZXh5MoYIphLp/aw2YqIVr4dS1Ji9lxQ34Fxb74A0f7huYjDZDipxwvsSA0YUNa415vQOU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1710349341; c=relaxed/simple; bh=1PzYjJECdyxJFAvQj2oALN2vIBxJLj4yYEea3o4T+TI=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=MGf49zIuGBXep/ilctBk+tvsyYg6p8ECloO/Dzmc0JzO+TQqPAnNZ6obyGuN7P8iul37Ozcc3LnsNmUj/RtWU/EO4CrduLb2tMyUc8WnTt141NFeYuzMw8qiW2iPm2RICeLbNd3WSgBNb6i279YzpVhgmRmJHbcfepGaA+aGLxs= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=UZqZtbMR; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="UZqZtbMR" Received: by smtp.kernel.org (Postfix) with ESMTPSA id CB0E2C43394; Wed, 13 Mar 2024 17:02:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1710349340; bh=1PzYjJECdyxJFAvQj2oALN2vIBxJLj4yYEea3o4T+TI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=UZqZtbMRDYMO/LX0YVIGcSvujNAT8uyDGnM85ZR/lfHVsq/vgmGf2+O41fiqZtcB9 IfbbkFYMzq3jsHo6q0lYMK88eWOZfhjuSrk3RoQ9jruJYCBSmxgmbddKVsYjaYhfOR AyVDS4dA1pgx5IclCcL+s760TNyiMtiFcC4mR2Q7YQpaQaUtdyTtnQIYpVy2Jw5d+3 5pgHb+dmOXWm0VGEofRHRZEI0hQaxYM7+gHxS8/J21abjBMClirbQ6GSutMWbGL5Lb L5yg/sZ8lhazOA0QkzpRD80Zbef/zNae+Rs3A1zUiU/5BggoJ0Y6LWo50k4fU60vQM nFeDdICoejoIw== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Oleksij Rempel , Jiri Pirko , "David S . Miller" , Sasha Levin Subject: [PATCH 5.4 05/51] net: lan78xx: fix runtime PM count underflow on link stop Date: Wed, 13 Mar 2024 13:01:26 -0400 Message-ID: <20240313170212.616443-6-sashal@kernel.org> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20240313170212.616443-1-sashal@kernel.org> References: <20240313170212.616443-1-sashal@kernel.org> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-KernelTest-Patch: http://kernel.org/pub/linux/kernel/v5.x/stable-review/patch-5.4.272-rc1.gz X-KernelTest-Tree: git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable-rc.git X-KernelTest-Branch: linux-5.4.y X-KernelTest-Patches: git://git.kernel.org/pub/scm/linux/kernel/git/stable/stable-queue.git X-KernelTest-Version: 5.4.272-rc1 X-KernelTest-Deadline: 2024-03-15T17:02+00:00 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit From: Oleksij Rempel [ Upstream commit 1eecc7ab82c42133b748e1895275942a054a7f67 ] Current driver has some asymmetry in the runtime PM calls. On lan78xx_open() it will call usb_autopm_get() and unconditionally usb_autopm_put(). And on lan78xx_stop() it will call only usb_autopm_put(). So far, it was working only because this driver do not activate autosuspend by default, so it was visible only by warning "Runtime PM usage count underflow!". Since, with current driver, we can't use runtime PM with active link, execute lan78xx_open()->usb_autopm_put() only in error case. Otherwise, keep ref counting high as long as interface is open. Fixes: 55d7de9de6c3 ("Microchip's LAN7800 family USB 2/3 to 10/100/1000 Ethernet device driver") Signed-off-by: Oleksij Rempel Reviewed-by: Jiri Pirko Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- drivers/net/usb/lan78xx.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/net/usb/lan78xx.c b/drivers/net/usb/lan78xx.c index 42fe7753ff76d..b0efaf56d78f3 100644 --- a/drivers/net/usb/lan78xx.c +++ b/drivers/net/usb/lan78xx.c @@ -2905,7 +2905,8 @@ static int lan78xx_open(struct net_device *net) done: mutex_unlock(&dev->dev_mutex); - usb_autopm_put_interface(dev->intf); + if (ret < 0) + usb_autopm_put_interface(dev->intf); return ret; } -- 2.43.0