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 X-Spam-Level: X-Spam-Status: No, score=-1.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 51F37C43381 for ; Mon, 18 Feb 2019 10:33:07 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 22388214DA for ; Mon, 18 Feb 2019 10:33:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729658AbfBRKdF (ORCPT ); Mon, 18 Feb 2019 05:33:05 -0500 Received: from icebox.esperi.org.uk ([81.187.191.129]:49550 "EHLO mail.esperi.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727004AbfBRKdF (ORCPT ); Mon, 18 Feb 2019 05:33:05 -0500 Received: from loom (nix@sidle.srvr.nix [192.168.14.8]) by mail.esperi.org.uk (8.15.2/8.15.2) with ESMTP id x1IASFBg024635; Mon, 18 Feb 2019 10:28:15 GMT From: Nix To: Johan Hovold Cc: Greg KH , linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: 4.20.7: pl2303 not working (post-4.19 regression) (limited info so far, not yet bisected) References: <87o97bu2bt.fsf@esperi.org.uk> <20190216194758.GA10756@kroah.com> <877edytehb.fsf@esperi.org.uk> <20190218075851.GA4072@localhost> Emacs: The Awakening Date: Mon, 18 Feb 2019 10:32:57 +0000 In-Reply-To: <20190218075851.GA4072@localhost> (Johan Hovold's message of "Mon, 18 Feb 2019 08:58:51 +0100") Message-ID: <87sgwls7xi.fsf@esperi.org.uk> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/26.1.50 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain X-DCC-wuwien-Metrics: loom 1290; Body=4 Fuz1=4 Fuz2=4 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 18 Feb 2019, Johan Hovold stated: > On Sun, Feb 17, 2019 at 07:13:52PM +0000, Nix wrote: >> I'm still fairly sure this is a regression -- my machines are often up >> for a lot longer than that and I've never seen this before I upgraded to >> 4.20.x -- but I don't think I'm going to identify it by mindless >> bisection. I might have to actually *think* about it. > > I doubt it's a regression in usb-serial as essentially nothing changed > with respect to pl2303 or core since 4.19. Yeah, I came to that conclusion as well. > The -ENOSPC you're seeing is returned by the host controller to > indicate: > > This request would overcommit the usb bandwidth reserved for > periodic transfers (interrupt, isochronous). Side note: probably not related to *this* -ENOSPC, which I've been seeing for a few releases now and which appears to break Chromium's U2F negotiation when the USB bus has sufficiently weird devices on it (like, uh, my wireless mouse): (I say "probably not related" because it's much older and long predates the pl2303 trouble.) > but if you're saying you can reproduce this on "every box" it may not be > related to any particular host-controller driver (or USB topology). They are all xhci, at least. The pl2303 is USB 2. One machine, a two-year-old Broadwell server, says: xhci_hcd 0000:00:14.0: xHCI Host Controller xhci_hcd 0000:00:14.0: new USB bus registered, assigned bus number 3 xhci_hcd 0000:00:14.0: hcc params 0x200077c1 hci version 0x100 quirks 0x0000000000009810 xhci_hcd 0000:00:14.0: cache line size of 32 is not supported hub 3-0:1.0: USB hub found hub 3-0:1.0: 15 ports detected xhci_hcd 0000:00:14.0: xHCI Host Controller xhci_hcd 0000:00:14.0: new USB bus registered, assigned bus number 4 xhci_hcd 0000:00:14.0: Host supports USB 3.0 SuperSpeed 00:14.0 USB controller: Intel Corporation C610/X99 series chipset USB xHCI Host Controller (rev 05) (prog-if 30 [XHCI]) The other, a 2012-era cheapish Ivy Bridge workstation: xhci_hcd 0000:03:00.0: xHCI Host Controller xhci_hcd 0000:03:00.0: new USB bus registered, assigned bus number 3 xhci_hcd 0000:03:00.0: hcc params 0x014042cb hci version 0x96 quirks 0x0000000000000004 hub 3-0:1.0: USB hub found hub 3-0:1.0: 2 ports detected xhci_hcd 0000:03:00.0: xHCI Host Controller xhci_hcd 0000:03:00.0: new USB bus registered, assigned bus number 4 xhci_hcd 0000:03:00.0: Host supports USB 3.0 SuperSpeed usb usb4: We don't know the algorithms for LPM for this host, disabling LPM. hub 4-0:1.0: USB hub found hub 4-0:1.0: 2 ports detected xhci_hcd 0000:04:00.0: xHCI Host Controller xhci_hcd 0000:04:00.0: new USB bus registered, assigned bus number 5 xhci_hcd 0000:04:00.0: hcc params 0x0200f180 hci version 0x96 quirks 0x0000000000080000 hub 5-0:1.0: USB hub found hub 5-0:1.0: 2 ports detected xhci_hcd 0000:04:00.0: xHCI Host Controller xhci_hcd 0000:04:00.0: new USB bus registered, assigned bus number 6 xhci_hcd 0000:04:00.0: Host supports USB 3.0 SuperSpeed usb usb6: We don't know the algorithms for LPM for this host, disabling LPM. 03:00.0 USB controller: NEC Corporation uPD720200 USB 3.0 Host Controller (rev 03) (prog-if 30 [XHCI]) 04:00.0 USB controller: ASMedia Technology Inc. ASM1042 SuperSpeed USB Host Controller (prog-if 30 [XHCI]) (I really don't know which of these is which. I suspect only one actually has any visible ports on the outside of the case...) So the quirks are all totally different, and the controllers are quite different as well...