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 D4F2A335BA3; Mon, 18 Aug 2025 13:48:25 +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=1755524905; cv=none; b=PlubFnpGuWvmCQEtwXiuYIXeDrJNfx/xO+lZ6iGjhpn9r6resxtbynYlqD13jL8+R/tFrKnnsEQBG4jX62hCHi19I2gn8p8+wTPpA1q5g37gl7y8GQyJi/NO4iqs4N9wTL3CcNbA28BdUVyLQlwt7xpFlVVlSFv0XHg5PRGrBkU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755524905; c=relaxed/simple; bh=7l2YmgdZzMKz9Ikult+SzNwdm/OL2tUYjcL1SagTgkI=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=bTngAH87pQkvLpl9bSWZXIEygJAEDSig/OmH2EvX3yHDka07z3OX0nxJnqTa8my4zWd5f3tsk6Rn0pBUd+BU4v8dZdz9/9GD514Lk/jkwzGdArGR0GcVNYhP93oM8mdOuhMNgwM8GFuiJEBAjrEW7WplSSx6iKrEFdpbj4Vcn5M= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=FpUnoLHP; 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="FpUnoLHP" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 4488BC4CEEB; Mon, 18 Aug 2025 13:48:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1755524905; bh=7l2YmgdZzMKz9Ikult+SzNwdm/OL2tUYjcL1SagTgkI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=FpUnoLHPm6r/aR3W8AOAnkCpMAsMrBAky9aQRN1X/3NnqiqVy32R26xiiwj03H/sM Chn7w6U+XAQ6RlaKumeC5zZsodGaOM2oNuyXo9ivX8Y2Fq8lQYKII29TP8tnK2AMO/ +f5sU5JMUQhPCDBKQq966JUiZYI5Bhuh6GLQunSo= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Jijie Shao , Simon Horman , Jakub Kicinski , Sasha Levin Subject: [PATCH 6.16 067/570] net: hibmcge: fix rtnl deadlock issue Date: Mon, 18 Aug 2025 14:40:54 +0200 Message-ID: <20250818124508.394288263@linuxfoundation.org> X-Mailer: git-send-email 2.50.1 In-Reply-To: <20250818124505.781598737@linuxfoundation.org> References: <20250818124505.781598737@linuxfoundation.org> User-Agent: quilt/0.68 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 6.16-stable review patch. If anyone has any objections, please let me know. ------------------ From: Jijie Shao [ Upstream commit c875503a9b9082928d7d3fc60b5400d16fbfae4e ] Currently, the hibmcge netdev acquires the rtnl_lock in pci_error_handlers.reset_prepare() and releases it in pci_error_handlers.reset_done(). However, in the PCI framework: pci_reset_bus - __pci_reset_slot - pci_slot_save_and_disable_locked - pci_dev_save_and_disable - err_handler->reset_prepare(dev); In pci_slot_save_and_disable_locked(): list_for_each_entry(dev, &slot->bus->devices, bus_list) { if (!dev->slot || dev->slot!= slot) continue; pci_dev_save_and_disable(dev); if (dev->subordinate) pci_bus_save_and_disable_locked(dev->subordinate); } This will iterate through all devices under the current bus and execute err_handler->reset_prepare(), causing two devices of the hibmcge driver to sequentially request the rtnl_lock, leading to a deadlock. Since the driver now executes netif_device_detach() before the reset process, it will not concurrently with other netdev APIs, so there is no need to hold the rtnl_lock now. Therefore, this patch removes the rtnl_lock during the reset process and adjusts the position of HBG_NIC_STATE_RESETTING to ensure that multiple resets are not executed concurrently. Fixes: 3f5a61f6d504f ("net: hibmcge: Add reset supported in this module") Signed-off-by: Jijie Shao Reviewed-by: Simon Horman Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- drivers/net/ethernet/hisilicon/hibmcge/hbg_err.c | 14 +++++--------- 1 file changed, 5 insertions(+), 9 deletions(-) diff --git a/drivers/net/ethernet/hisilicon/hibmcge/hbg_err.c b/drivers/net/ethernet/hisilicon/hibmcge/hbg_err.c index ff3295b60a69..dee1e8681157 100644 --- a/drivers/net/ethernet/hisilicon/hibmcge/hbg_err.c +++ b/drivers/net/ethernet/hisilicon/hibmcge/hbg_err.c @@ -53,9 +53,11 @@ static int hbg_reset_prepare(struct hbg_priv *priv, enum hbg_reset_type type) { int ret; - ASSERT_RTNL(); + if (test_and_set_bit(HBG_NIC_STATE_RESETTING, &priv->state)) + return -EBUSY; if (netif_running(priv->netdev)) { + clear_bit(HBG_NIC_STATE_RESETTING, &priv->state); dev_warn(&priv->pdev->dev, "failed to reset because port is up\n"); return -EBUSY; @@ -64,7 +66,6 @@ static int hbg_reset_prepare(struct hbg_priv *priv, enum hbg_reset_type type) netif_device_detach(priv->netdev); priv->reset_type = type; - set_bit(HBG_NIC_STATE_RESETTING, &priv->state); clear_bit(HBG_NIC_STATE_RESET_FAIL, &priv->state); ret = hbg_hw_event_notify(priv, HBG_HW_EVENT_RESET); if (ret) { @@ -83,28 +84,25 @@ static int hbg_reset_done(struct hbg_priv *priv, enum hbg_reset_type type) type != priv->reset_type) return 0; - ASSERT_RTNL(); - - clear_bit(HBG_NIC_STATE_RESETTING, &priv->state); ret = hbg_rebuild(priv); if (ret) { set_bit(HBG_NIC_STATE_RESET_FAIL, &priv->state); + clear_bit(HBG_NIC_STATE_RESETTING, &priv->state); dev_err(&priv->pdev->dev, "failed to rebuild after reset\n"); return ret; } netif_device_attach(priv->netdev); + clear_bit(HBG_NIC_STATE_RESETTING, &priv->state); dev_info(&priv->pdev->dev, "reset done\n"); return ret; } -/* must be protected by rtnl lock */ int hbg_reset(struct hbg_priv *priv) { int ret; - ASSERT_RTNL(); ret = hbg_reset_prepare(priv, HBG_RESET_TYPE_FUNCTION); if (ret) return ret; @@ -169,7 +167,6 @@ static void hbg_pci_err_reset_prepare(struct pci_dev *pdev) struct net_device *netdev = pci_get_drvdata(pdev); struct hbg_priv *priv = netdev_priv(netdev); - rtnl_lock(); hbg_reset_prepare(priv, HBG_RESET_TYPE_FLR); } @@ -179,7 +176,6 @@ static void hbg_pci_err_reset_done(struct pci_dev *pdev) struct hbg_priv *priv = netdev_priv(netdev); hbg_reset_done(priv, HBG_RESET_TYPE_FLR); - rtnl_unlock(); } static const struct pci_error_handlers hbg_pci_err_handler = { -- 2.50.1