From mboxrd@z Thu Jan 1 00:00:00 1970 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 501BFC433EF for ; Wed, 1 Dec 2021 10:57:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238038AbhLALA6 (ORCPT ); Wed, 1 Dec 2021 06:00:58 -0500 Received: from bhuna.collabora.co.uk ([46.235.227.227]:34866 "EHLO bhuna.collabora.co.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1348970AbhLALAU (ORCPT ); Wed, 1 Dec 2021 06:00:20 -0500 Received: from [IPv6:2a00:23c6:c31a:b300:ebaf:3237:6d4:4abc] (unknown [IPv6:2a00:23c6:c31a:b300:ebaf:3237:6d4:4abc]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) (Authenticated sender: martyn) by bhuna.collabora.co.uk (Postfix) with ESMTPSA id 649C01F4582C; Wed, 1 Dec 2021 10:56:58 +0000 (GMT) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=collabora.com; s=mail; t=1638356218; bh=Ih4XEBSFrmawdMqurt9cKh1iAmZVVdPtBlcieQ4EF6Q=; h=Subject:From:To:Cc:Date:In-Reply-To:References:From; b=KDTljOxqAycvZOVA5A+uVujeUJQSsL/S9nWy7syLS0oczPmHYNQXIESkKEXKnhQsB 9URKR7irowT6CAeBb+XfSjf4UtX3RABzrUdwHKrOM5OLB9SwTiMP93E3R4AcuJLTdB BbPdn2CAZWyaMY5g8Migh8QU5RoEy8IKGPHzV1cCU192GcZeiYJ1wN/R0T6uKg0FAp lMuH+A8RUtRD230/+ZFrPcm2WcP4z8Bt4xf6C12xPe2yE9TwfnUl9OJOjJ/Fc8Hgww Ty0q6NSY8zaVBEzLqes06MEOID3FnhLHP5Q5tDxkf80MDuqmD+HNZkFYN4sKVLkozR 2TyrXIUN1oZ9w== Message-ID: <4f7b5ddfbd4d51d6d676a8691db0a5d33b7c35d0.camel@collabora.com> Subject: Re: [PATCH] net: usb: Correct PHY handling of smsc95xx From: Martyn Welch To: Ferry Toth , netdev@vger.kernel.org Cc: linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org, kernel@collabora.com, Steve Glendinning , UNGLinuxDriver@microchip.com, "David S. Miller" , Jakub Kicinski , stable@kernel.org Date: Wed, 01 Dec 2021 10:56:55 +0000 In-Reply-To: <43ff7a4b-fce4-6ad1-4cea-67ef42234831@gmail.com> References: <20211122184445.1159316-1-martyn.welch@collabora.com> <5cd6fc87-0f8d-0b9b-42be-8180540a94e7@gmail.com> <6a06e3b7-df08-6ec0-6e74-95c21fa43f38@gmail.com> <93d3bb50040dd4519a65187d3412973831d2d797.camel@collabora.com> <43ff7a4b-fce4-6ad1-4cea-67ef42234831@gmail.com> Organization: Collabora Ltd. Content-Type: text/plain; charset="UTF-8" User-Agent: Evolution 3.42.1-1 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org On Tue, 2021-11-30 at 22:47 +0100, Ferry Toth wrote: > Op 30-11-2021 om 19:52 schreef Martyn Welch: > > On Mon, 2021-11-29 at 15:16 +0100, Ferry Toth wrote: > > > Hi, > > > Op 29-11-2021 om 13:08 schreef Martyn Welch: > > >   > > > > On Sat, 2021-11-27 at 18:48 +0100, Ferry Toth wrote: > > > >   > > > > > > > > > > The patch introduces a new error on each unplug: > > > > > > > > > > usb 1-1: USB disconnect, device number 2 > > > > > usb 1-1.1: USB disconnect, device number 3 > > > > > smsc95xx 1-1.1:1.0 eth0: unregister 'smsc95xx' usb-xhci- > > > > > hcd.1.auto- > > > > > 1.1, > > > > > smsc95xx USB 2.0 Ethernet > > > > > smsc95xx 1-1.1:1.0 eth0: Link is Down > > > > > smsc95xx 1-1.1:1.0 eth0: Failed to read reg index 0x00000114: - > > > > > 19 > > > > > smsc95xx 1-1.1:1.0 eth0: Error reading MII_ACCESS > > > > > smsc95xx 1-1.1:1.0 eth0: __smsc95xx_mdio_read: MII is busy > > > > > smsc95xx 1-1.1:1.0 eth0: Failed to read reg index 0x00000114: - > > > > > 19 > > > > > smsc95xx 1-1.1:1.0 eth0: Error reading MII_ACCESS > > > > > smsc95xx 1-1.1:1.0 eth0: __smsc95xx_mdio_read: MII is busy > > > > > smsc95xx 1-1.1:1.0 eth0: hardware isn't capable of remote > > > > > wakeup > > > > > > > > > Agh! Somehow missed that. I'm looking into it... > > >   That would be great! > > >   > > > > They appear as a result of phy_disconnect() being called in unbind() > > when the hardware has already been disconnected (which is kinda > > likely > > to physically be the case with USB devices...). The PHY is not going > > to > > be accessible, but such calls *are* needed for instances where we are > > unbinding without the device having been physically removed and want > > to > > put the device in a suitable state. Failing with -ENODEV (as it > > currently does) seems to be the right thing to do. > > > > I wonder whether removing some of these error messages might be an > > option? It appears that some of them are present in other drivers, > > but > > I don't know whether such messages get displayed when that hardware > > is > > unplugged too or whether I'm missing something that protects against > > that. > I just retried 5.10.63 and found it did not yet have the crash that you > fix here. But it did have the above Error reading MII_ACCESS. So > apparently this is more of an older annoyance since smsc95xx v2.00? That's an interesting observation. Trying the v4.19 stable branch I see that these errors aren't generated, however it seems that the driver at that point may not be making any attempt to stop the PHY when the driver is unbound/disconnected, which explains the lack of errors. > > > > > > > >   > > > > > Also as reported earlier, (only) on first plug the more > > > > > worrying > > > > > but > > > > > possibly unrelated crash still happens: > > > > > ------------[ cut here ]------------ > > > > > DMA-API: xhci-hcd xhci-hcd.1.auto: cacheline tracking EEXIST, > > > > > overlapping mappings aren't supported > > > > > WARNING: CPU: 0 PID: 23 at kernel/dma/debug.c:570 > > > > > add_dma_entry+0x1d9/0x270 > > > > > Modules linked in: rfcomm iptable_nat bnep usb_f_uac2 u_audio > > > > > snd_sof_nocodec usb_f_mass_storage usb_f_eem u_ether > > > > > spi_pxa2xx_platform > > > > > dw_dmac usb_f_serial u_serial libcomposite intel_mrfld_pwrbtn > > > > > snd_sof_pci_intel_tng pwm_lpss_pci intel_mrfld_adc pwm_lpss > > > > > snd_sof_pci > > > > > snd_sof_intel_ipc snd_sof_intel_atom dw_dmac_pci dw_dmac_core > > > > > snd_sof > > > > > snd_sof_xtensa_dsp snd_soc_acpi spi_pxa2xx_pci brcmfmac > > > > > brcmutil > > > > > hci_uart leds_gpio btbcm ti_ads7950 > > > > > industrialio_triggered_buffer > > > > > kfifo_buf tun ledtrig_timer ledtrig_heartbeat mmc_block > > > > > extcon_intel_mrfld sdhci_pci cqhci sdhci led_class mmc_core > > > > > intel_soc_pmic_mrfld btrfs libcrc32c xor zstd_compress > > > > > zlib_deflate > > > > > raid6_pq > > > > > CPU: 0 PID: 23 Comm: kworker/0:1 Not tainted 5.15.1-edison- > > > > > acpi- > > > > > standard #1 > > > > > Hardware name: Intel Corporation Merrifield/BODEGA BAY, BIOS > > > > > 542 > > > > > 2015.01.21:18.19.48 > > > > > Workqueue: usb_hub_wq hub_event > > > > > RIP: 0010:add_dma_entry+0x1d9/0x270 > > > > > Code: ff 0f 84 97 00 00 00 4c 8b 67 50 4d 85 e4 75 03 4c 8b > > > > > 27 e8 > > > > > 39 > > > > > ff > > > > > 52 00 48 89 c6 4c 89 e2 48 c7 c7 f0 ab e7 a7 e8 c7 5c b5 00 > > > > > <0f> 0b > > > > > 48 > > > > > 85 ed 0f 85 a4 b3 b5 00 8b 05 46 38 9f 01 85 c0 0f 85 df > > > > > RSP: 0000:ffffb047400cfac8 EFLAGS: 00010282 > > > > > RAX: 0000000000000000 RBX: 00000000ffffffff RCX: > > > > > ffff9e25fe217478 > > > > > RDX: 00000000ffffffd8 RSI: 0000000000000027 RDI: > > > > > ffff9e25fe217470 > > > > > RBP: ffff9e25c12ff780 R08: ffffffffa83359a8 R09: > > > > > 0000000000009ffb > > > > > R10: 00000000ffffe000 R11: 3fffffffffffffff R12: > > > > > ffff9e25c8a24040 > > > > > R13: 0000000000000001 R14: 0000000000000206 R15: > > > > > 00000000000f8be4 > > > > > FS:  0000000000000000(0000) GS:ffff9e25fe200000(0000) > > > > > knlGS:0000000000000000 > > > > > CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > > > > > CR2: 00007f62c6d586d8 CR3: 0000000002f3c000 CR4: > > > > > 00000000001006f0 > > > > > Call Trace: > > > > >    dma_map_page_attrs+0xfb/0x250 > > > > >    ? usb_hcd_link_urb_to_ep+0x14/0xa0 > > > > >    usb_hcd_map_urb_for_dma+0x3b1/0x4e0 > > > > >    usb_hcd_submit_urb+0x93/0xbb0 > > > > >    ? create_prof_cpu_mask+0x20/0x20 > > > > >    ? arch_stack_walk+0x73/0xf0 > > > > >    ? usb_hcd_link_urb_to_ep+0x14/0xa0 > > > > >    ? prepare_transfer+0xff/0x140 > > > > >    usb_start_wait_urb+0x60/0x160 > > > > >    usb_control_msg+0xda/0x140 > > > > >    hub_ext_port_status+0x82/0x100 > > > > >    hub_event+0x1b1/0x1830 > > > > >    ? hub_activate+0x58c/0x860 > > > > >    process_one_work+0x1d4/0x370 > > > > >    worker_thread+0x48/0x3d0 > > > > >    ? rescuer_thread+0x360/0x360 > > > > >    kthread+0x122/0x140 > > > > >    ? set_kthread_struct+0x40/0x40 > > > > >    ret_from_fork+0x22/0x30 > > > > > ---[ end trace da6ffcd9fad23a74 ]--- > > > > > DMA-API: Mapped at: > > > > >    debug_dma_map_page+0x60/0xf0 > > > > >    dma_map_page_attrs+0xfb/0x250 > > > > >    usb_hcd_map_urb_for_dma+0x3b1/0x4e0 > > > > >    usb_hcd_submit_urb+0x93/0xbb0 > > > > >    usb_start_wait_urb+0x60/0x160 > > > > > usb 1-1.1: new high-speed USB device number 3 using xhci-hcd > > > > > usb 1-1.1: New USB device found, idVendor=0424, > > > > > idProduct=ec00, > > > > > bcdDevice= 2.00 > > > > > usb 1-1.1: New USB device strings: Mfr=1, Product=2, > > > > > SerialNumber=3 > > > > > usb 1-1.1: Product: LAN9514 > > > > > usb 1-1.1: Manufacturer: SMSC > > > > > usb 1-1.1: SerialNumber: 00951d0d > > > > > > > > > > > > > > I'm not seeing that at all, but I've also been developing and > > > > testing > > > > on an ARM based device that has the LAN9500A I'm using built > > > > into it. > > > > > > > > I have also recently got a LAN9500A devkit which I've tried on > > > > my > > > > Ryzen > > > > laptop and that's not throwing that error either. > > > > > > > > Martyn > > > Yes I am using the LAN9514 Evaluation board (EVB9514). Plugging > > > the > > > board into my desktop with 5.15 Ubuntu PPA kernel I also don't > > > see this > > > crash. > > > OTOH I'm building vanilla kernel so no idea why this happens. It > > > might > > > be that I have CONFIG_DMA_API_DEBUG and Ubuntu not. > > >   > > > > I suspect this is probably unrelated (directly) to the driver then. > > Maybe not related to this driver but possibly an old bug in hub.c > which > only surfaces now due to patch "[PATCH] dma debug: report -EEXIST > errors > in add_dma_entry"? And only shows when CONFIG_DMA_API_DEBUG is set? > > Ferry > > > Martyn > > > > > >