From patchwork Tue Apr 28 18:24:31 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg Kroah-Hartman X-Patchwork-Id: 226845 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=-6.8 required=3.0 tests=DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED, USER_AGENT_GIT autolearn=unavailable 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 37F4FC83008 for ; Tue, 28 Apr 2020 18:46:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 12A9220575 for ; Tue, 28 Apr 2020 18:46:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1588099570; bh=c9H+qpd47HYJ1J9D3GTa+VjseQBJ8oDJHKlKlFAPWDc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=jXSNMQ5XyHUl2lH7x/3uBsyoeA/VuQkPnCx2p4bY2aV/PutVOElkIeavLOAJWBj4w MSWcJAhcnsyEuiGBtAIWOPD4nPSgs/KezzZvQCAWdwhVyPUjWcklV4qJPyAeFFDtjg ZtMUcgPjgQHwjC9Xuv/y2XuDyGtE4wZZpSDS2olY= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731226AbgD1Snc (ORCPT ); Tue, 28 Apr 2020 14:43:32 -0400 Received: from mail.kernel.org ([198.145.29.99]:35938 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730284AbgD1Snb (ORCPT ); Tue, 28 Apr 2020 14:43:31 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 29C8E20730; Tue, 28 Apr 2020 18:43:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1588099410; bh=c9H+qpd47HYJ1J9D3GTa+VjseQBJ8oDJHKlKlFAPWDc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=TmAOsZZubuC+FUTpLa3CsxpKeBPaWqrhFXP+HMD2HFDiVAQbQzu3c2eBsEfDL8L6f oNZ9mqxyEKjBe2rsgD0Zv2dEQV86ZYtxUPxLi4lfI2VaLRksvrwGsj4up70x9vPxe+ iXPx6fGJ70S1I/3nUpEr1nNtdBWzNEgMV+aTchAM= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Jann Horn Subject: [PATCH 5.4 097/168] USB: early: Handle AMDs spec-compliant identifiers, too Date: Tue, 28 Apr 2020 20:24:31 +0200 Message-Id: <20200428182244.617311979@linuxfoundation.org> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20200428182231.704304409@linuxfoundation.org> References: <20200428182231.704304409@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Jann Horn commit 7dbdb53d72a51cea9b921d9dbba54be00752212a upstream. This fixes a bug that causes the USB3 early console to freeze after printing a single line on AMD machines because it can't parse the Transfer TRB properly. The spec at https://www.intel.com/content/dam/www/public/us/en/documents/technical-specifications/extensible-host-controler-interface-usb-xhci.pdf says in section "4.5.1 Device Context Index" that the Context Index, also known as Endpoint ID according to section "1.6 Terms and Abbreviations", is normally computed as `DCI = (Endpoint Number * 2) + Direction`, which matches the current definitions of XDBC_EPID_OUT and XDBC_EPID_IN. However, the numbering in a Debug Capability Context data structure is supposed to be different: Section "7.6.3.2 Endpoint Contexts and Transfer Rings" explains that a Debug Capability Context data structure has the endpoints mapped to indices 0 and 1. Change XDBC_EPID_OUT/XDBC_EPID_IN to the spec-compliant values, add XDBC_EPID_OUT_INTEL/XDBC_EPID_IN_INTEL with Intel's incorrect values, and let xdbc_handle_tx_event() handle both. I have verified that with this patch applied, the USB3 early console works on both an Intel and an AMD machine. Fixes: aeb9dd1de98c ("usb/early: Add driver for xhci debug capability") Cc: stable@vger.kernel.org Signed-off-by: Jann Horn Link: https://lore.kernel.org/r/20200401074619.8024-1-jannh@google.com Signed-off-by: Greg Kroah-Hartman --- drivers/usb/early/xhci-dbc.c | 8 ++++---- drivers/usb/early/xhci-dbc.h | 18 ++++++++++++++++-- 2 files changed, 20 insertions(+), 6 deletions(-) --- a/drivers/usb/early/xhci-dbc.c +++ b/drivers/usb/early/xhci-dbc.c @@ -728,19 +728,19 @@ static void xdbc_handle_tx_event(struct case COMP_USB_TRANSACTION_ERROR: case COMP_STALL_ERROR: default: - if (ep_id == XDBC_EPID_OUT) + if (ep_id == XDBC_EPID_OUT || ep_id == XDBC_EPID_OUT_INTEL) xdbc.flags |= XDBC_FLAGS_OUT_STALL; - if (ep_id == XDBC_EPID_IN) + if (ep_id == XDBC_EPID_IN || ep_id == XDBC_EPID_IN_INTEL) xdbc.flags |= XDBC_FLAGS_IN_STALL; xdbc_trace("endpoint %d stalled\n", ep_id); break; } - if (ep_id == XDBC_EPID_IN) { + if (ep_id == XDBC_EPID_IN || ep_id == XDBC_EPID_IN_INTEL) { xdbc.flags &= ~XDBC_FLAGS_IN_PROCESS; xdbc_bulk_transfer(NULL, XDBC_MAX_PACKET, true); - } else if (ep_id == XDBC_EPID_OUT) { + } else if (ep_id == XDBC_EPID_OUT || ep_id == XDBC_EPID_OUT_INTEL) { xdbc.flags &= ~XDBC_FLAGS_OUT_PROCESS; } else { xdbc_trace("invalid endpoint id %d\n", ep_id); --- a/drivers/usb/early/xhci-dbc.h +++ b/drivers/usb/early/xhci-dbc.h @@ -120,8 +120,22 @@ struct xdbc_ring { u32 cycle_state; }; -#define XDBC_EPID_OUT 2 -#define XDBC_EPID_IN 3 +/* + * These are the "Endpoint ID" (also known as "Context Index") values for the + * OUT Transfer Ring and the IN Transfer Ring of a Debug Capability Context data + * structure. + * According to the "eXtensible Host Controller Interface for Universal Serial + * Bus (xHCI)" specification, section "7.6.3.2 Endpoint Contexts and Transfer + * Rings", these should be 0 and 1, and those are the values AMD machines give + * you; but Intel machines seem to use the formula from section "4.5.1 Device + * Context Index", which is supposed to be used for the Device Context only. + * Luckily the values from Intel don't overlap with those from AMD, so we can + * just test for both. + */ +#define XDBC_EPID_OUT 0 +#define XDBC_EPID_IN 1 +#define XDBC_EPID_OUT_INTEL 2 +#define XDBC_EPID_IN_INTEL 3 struct xdbc_state { u16 vendor;