From nobody Tue Sep 30 10:16:20 2025 X-Original-To: dev-commits-doc-all@mlmmj.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mlmmj.nyi.freebsd.org (Postfix) with ESMTP id 4cbYqn0cYsz68rJV for ; Tue, 30 Sep 2025 10:16:21 +0000 (UTC) (envelope-from git@FreeBSD.org) Received: from mxrelay.nyi.freebsd.org (mxrelay.nyi.freebsd.org [IPv6:2610:1c1:1:606c::19:3]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256 client-signature RSA-PSS (4096 bits) client-digest SHA256) (Client CN "mxrelay.nyi.freebsd.org", Issuer "R12" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 4cbYqn0646z3LfS; Tue, 30 Sep 2025 10:16:21 +0000 (UTC) (envelope-from git@FreeBSD.org) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1759227381; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=vQkE5TxG5WBnYMmPMzNksNyb71/Bxmo5dr3f2109uh4=; b=RnenBiZipf3dIp49Hih3wtKGuJhcJ4RN0s0lNMhxpoA4BsxEO33l36KoUCBJGVXU6/mZqW L6Rjaf6UyWdFMC8KeOtWyQNop02zNbS1/rxObjuj3Yk6jaK2kMLVloeKXyKNnzlmYhS2tj ZMzY8XRBppRS3EXWkQso2PAujPZN8kXpMM5bkmfuVe9dSgePF3l8cYOvHDqsdRSLe6L7XM 66evSgjCPbI+Cv7BYUdtUd9z0wqCJtJw/ORLi2DFPVWMLjv2LvRg0JBzJwk7ls0lk9UNj9 wokmS2n+91zRZw5GRnLZKDkBdlitK6HV51yQKlSF/vjYgJusxOz8jo81QbhcUQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1759227381; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=vQkE5TxG5WBnYMmPMzNksNyb71/Bxmo5dr3f2109uh4=; b=g5Jx4/S6cssDsgolNtuUZWG5t/uqPpyXnABlOlAJ1IfA4V03rztpMHQG2SWV3VwevCpyqv WJdRyBKo5I5sAmR1vGJkagKKXvdeUdWuMldMhubqDfmtiX194k6PJ0GF0llzG53tnT1PiD kwdVBsCL/yTB99Hxwm19vuJI0y9+kreHnai/A5/aA0eDLXv7K6oJszIQNBzCvPFC2liz1v ukpCMcqf5hnINXEu35PAQ+8qaJ6jRmj1OO78jO6fYbJeWO4B4sh806AySmkZJFeQecOpS6 r1J9eBxPLYchrTHRAAgetrO3n0QWYx6TcrSRafWB/jEAqcsWwt+WJLNfhnDUmg== ARC-Seal: i=1; s=dkim; d=freebsd.org; t=1759227381; a=rsa-sha256; cv=none; b=d318dMyyr0mR2IOkSmy7wplcBGzNIYQ2x9G3CQbV5Feyi4n3Otu54Qngd7CNyjakq4V0Hh RgFunSGCAni5JGX/Hwi5cJxjuZ4MyEYuhDbwdg5KUwl6jx32Y/WBR3MYGjMGU1HEGZHQuf VM+5NU/fSijxaq++ZubvaBNPPNDZ7pmp5WW9xG1vn569JtE6LgxERimdA0209jzaQFpEM4 Yqg/0oWozO3nJXExat+obEWwQAjd1y/7VNfE92sQ8j6hmxngzIHlQpCcjQhsFnMGlJ+iqA HmQXE8WDxJM/nkUbwHR+fab5mlG2F7dbqqYPus48hv2b92mZX1XPDWpXzvOXqw== ARC-Authentication-Results: i=1; mx1.freebsd.org; none Received: from gitrepo.freebsd.org (gitrepo.freebsd.org [IPv6:2610:1c1:1:6068::e6a:5]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (Client did not present a certificate) by mxrelay.nyi.freebsd.org (Postfix) with ESMTPS id 4cbYqm6cgczXh4; Tue, 30 Sep 2025 10:16:20 +0000 (UTC) (envelope-from git@FreeBSD.org) Received: from gitrepo.freebsd.org ([127.0.1.44]) by gitrepo.freebsd.org (8.18.1/8.18.1) with ESMTP id 58UAGK3l052655; Tue, 30 Sep 2025 10:16:20 GMT (envelope-from git@gitrepo.freebsd.org) Received: (from git@localhost) by gitrepo.freebsd.org (8.18.1/8.18.1/Submit) id 58UAGKnn052652; Tue, 30 Sep 2025 10:16:20 GMT (envelope-from git) Date: Tue, 30 Sep 2025 10:16:20 GMT Message-Id: <202509301016.58UAGKnn052652@gitrepo.freebsd.org> To: doc-committers@FreeBSD.org, dev-commits-doc-all@FreeBSD.org From: Tom Jones Subject: git: 3a3aaf464a - main - Status/2025/Q3/usb-debugging.adoc: Add status report List-Id: Commit messages for all branches of the doc repository List-Archive: https://lists.freebsd.org/archives/dev-commits-doc-all List-Help: List-Post: List-Subscribe: List-Unsubscribe: X-BeenThere: dev-commits-doc-all@freebsd.org Sender: owner-dev-commits-doc-all@FreeBSD.org MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit X-Git-Committer: thj X-Git-Repository: doc X-Git-Refname: refs/heads/main X-Git-Reftype: branch X-Git-Commit: 3a3aaf464aacc41aa00454ccbca01651127bc8ed Auto-Submitted: auto-generated The branch main has been updated by thj: URL: https://cgit.FreeBSD.org/doc/commit/?id=3a3aaf464aacc41aa00454ccbca01651127bc8ed commit 3a3aaf464aacc41aa00454ccbca01651127bc8ed Author: Tom Jones AuthorDate: 2025-09-30 10:15:37 +0000 Commit: Tom Jones CommitDate: 2025-09-30 10:15:37 +0000 Status/2025/Q3/usb-debugging.adoc: Add status report Add a status report for USB debugging interface. Reviewed by: salvadore Differential Revision: https://reviews.freebsd.org/D52571 --- .../report-2025-07-2025-09/usb-debugging.adoc | 22 ++++++++++++++++++++++ 1 file changed, 22 insertions(+) diff --git a/website/content/en/status/report-2025-07-2025-09/usb-debugging.adoc b/website/content/en/status/report-2025-07-2025-09/usb-debugging.adoc new file mode 100644 index 0000000000..92e26bd073 --- /dev/null +++ b/website/content/en/status/report-2025-07-2025-09/usb-debugging.adoc @@ -0,0 +1,22 @@ +=== USB Kernel Debugging Improvements + +Contact: Tom Jones + +XHCI USB controllers offer a mode which allows them to be used as a system debugging interface. +XHCI debug uses a special USB 3 cable with VBUS, D+ and D- disconnected. +The feature can be used to live debug the FreeBSD kernel, enabling investigation of issues which cause the system video console to lock up and there is not an alternative such as a serial console. +This can happen when debugging issues with graphics drivers. + +mailto:hrs@FreeBSD.org[Hiroki Sato] developed support for the XHCI debug interface and made it available as some in progress git branches. +This implementation enables FreeBSD to operate as both a Debug Host and a Debug Target, with support for debugging from the loader through to the kernel. + +In this quarter the Debug Host side of the XHCI debug has been committed to FreeBSD main and will be available in FreeBSD 15. +The Debug Host driver enables a FreeBSD machine to debug Linux and Windows systems acting as Debug Targets. +The Debug Host driver has been split from the patch series to enable debugging of FreeBSD 16 and onwards from FreeBSD 15. + +The Debug Target side of XHCI debug has progressed in this quarter, with an improved interface between the loader and the kernel and a lock up sending data from a Target resolved. +The remaining work for the host implementation is to enable XHCI debug as a console very early in boot and to convert some methods to use bus space allocations. + +In the coming quarter I plan to update the developers handbook section on kernel debugging. + +Sponsor: The FreeBSD Foundation