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 C878F9446 for ; Sun, 13 Aug 2023 21:37:28 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 50EECC433C7; Sun, 13 Aug 2023 21:37:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1691962648; bh=JOEaiS4VsnMNMCPECevu7X2SMwUnUorjUgLnle49tPs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=OJkoZSP3aaxO0QjfwMk/ZnIdBQYlA2E8Gfi5l7dzCTcyzn/+Td06/xvCtzIbCAIpG ZlTuVDzZ4uSvji7ssDyRMkfc7brmYNgwnMOIOTH+4nBh9L2ihtBIKscTjlDyNgc1nY +zzaiixlT8rLVx4aExe/jI1XXABBTNtqtNq4/v6k= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Vladimir Oltean , Jakub Kicinski Subject: [PATCH 6.1 106/149] net: dsa: ocelot: call dsa_tag_8021q_unregister() under rtnl_lock() on driver remove Date: Sun, 13 Aug 2023 23:19:11 +0200 Message-ID: <20230813211721.940607230@linuxfoundation.org> X-Mailer: git-send-email 2.41.0 In-Reply-To: <20230813211718.757428827@linuxfoundation.org> References: <20230813211718.757428827@linuxfoundation.org> User-Agent: quilt/0.67 Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From: Vladimir Oltean commit a94c16a2fda010866b8858a386a8bfbeba4f72c5 upstream. When the tagging protocol in current use is "ocelot-8021q" and we unbind the driver, we see this splat: $ echo '0000:00:00.2' > /sys/bus/pci/drivers/fsl_enetc/unbind mscc_felix 0000:00:00.5 swp0: left promiscuous mode sja1105 spi2.0: Link is Down DSA: tree 1 torn down mscc_felix 0000:00:00.5 swp2: left promiscuous mode sja1105 spi2.2: Link is Down DSA: tree 3 torn down fsl_enetc 0000:00:00.2 eno2: left promiscuous mode mscc_felix 0000:00:00.5: Link is Down ------------[ cut here ]------------ RTNL: assertion failed at net/dsa/tag_8021q.c (409) WARNING: CPU: 1 PID: 329 at net/dsa/tag_8021q.c:409 dsa_tag_8021q_unregister+0x12c/0x1a0 Modules linked in: CPU: 1 PID: 329 Comm: bash Not tainted 6.5.0-rc3+ #771 pc : dsa_tag_8021q_unregister+0x12c/0x1a0 lr : dsa_tag_8021q_unregister+0x12c/0x1a0 Call trace: dsa_tag_8021q_unregister+0x12c/0x1a0 felix_tag_8021q_teardown+0x130/0x150 felix_teardown+0x3c/0xd8 dsa_tree_teardown_switches+0xbc/0xe0 dsa_unregister_switch+0x168/0x260 felix_pci_remove+0x30/0x60 pci_device_remove+0x4c/0x100 device_release_driver_internal+0x188/0x288 device_links_unbind_consumers+0xfc/0x138 device_release_driver_internal+0xe0/0x288 device_driver_detach+0x24/0x38 unbind_store+0xd8/0x108 drv_attr_store+0x30/0x50 ---[ end trace 0000000000000000 ]--- ------------[ cut here ]------------ RTNL: assertion failed at net/8021q/vlan_core.c (376) WARNING: CPU: 1 PID: 329 at net/8021q/vlan_core.c:376 vlan_vid_del+0x1b8/0x1f0 CPU: 1 PID: 329 Comm: bash Tainted: G W 6.5.0-rc3+ #771 pc : vlan_vid_del+0x1b8/0x1f0 lr : vlan_vid_del+0x1b8/0x1f0 dsa_tag_8021q_unregister+0x8c/0x1a0 felix_tag_8021q_teardown+0x130/0x150 felix_teardown+0x3c/0xd8 dsa_tree_teardown_switches+0xbc/0xe0 dsa_unregister_switch+0x168/0x260 felix_pci_remove+0x30/0x60 pci_device_remove+0x4c/0x100 device_release_driver_internal+0x188/0x288 device_links_unbind_consumers+0xfc/0x138 device_release_driver_internal+0xe0/0x288 device_driver_detach+0x24/0x38 unbind_store+0xd8/0x108 drv_attr_store+0x30/0x50 DSA: tree 0 torn down This was somewhat not so easy to spot, because "ocelot-8021q" is not the default tagging protocol, and thus, not everyone who tests the unbinding path may have switched to it beforehand. The default felix_tag_npi_teardown() does not require rtnl_lock() to be held. Fixes: 7c83a7c539ab ("net: dsa: add a second tagger for Ocelot switches based on tag_8021q") Signed-off-by: Vladimir Oltean Link: https://lore.kernel.org/r/20230803134253.2711124-1-vladimir.oltean@nxp.com Signed-off-by: Jakub Kicinski Signed-off-by: Greg Kroah-Hartman --- drivers/net/dsa/ocelot/felix.c | 2 ++ 1 file changed, 2 insertions(+) --- a/drivers/net/dsa/ocelot/felix.c +++ b/drivers/net/dsa/ocelot/felix.c @@ -1606,8 +1606,10 @@ static void felix_teardown(struct dsa_sw struct felix *felix = ocelot_to_felix(ocelot); struct dsa_port *dp; + rtnl_lock(); if (felix->tag_proto_ops) felix->tag_proto_ops->teardown(ds); + rtnl_unlock(); dsa_switch_for_each_available_port(dp, ds) ocelot_deinit_port(ocelot, dp->index);