From nobody Sun Feb 8 17:33:16 2026 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (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 3EBB21C6A3; Sat, 30 Nov 2024 08:11:13 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=198.137.202.133 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1732954278; cv=none; b=rsTvu5GZcAG7frhmfI4kL9rJhQTbZYaaHpeQek4W/yRK1MJ4+92LAfLUJ8gy/swaw0XlD/LXhKRQ7TpQ7HP8GHxWPGl2V4ldw3LBx8BwURLm17m9w2GKYKSlRXVLNfAZ9jFw3b4fdbsKKksbFVZbjVC1MprVyRIktMPe+yhJ9nw= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1732954278; c=relaxed/simple; bh=EtUbSjB4gtYtVLUlsE3YgcWWNyk4Mo2DOpSuiOaiWDo=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version:Content-Type; b=kNIJFnMWAx6WSwPlGe6ZI6OlD1MzLrf81NYo+rztL1hIBV/3v0RQFyY/pNFP5+mH54zMtc7CMvTqfIZuXshM+JUCj6+gSQAWTIDI/TkHd2QzVpQTREuPvfQ6jMaeL9no5kJ7f8kVSjPYe7rnJIlIPqmqMUVOPZohT02+5VUxlPU= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org; spf=none smtp.mailfrom=infradead.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b=R3oRwHav; arc=none smtp.client-ip=198.137.202.133 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=infradead.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="R3oRwHav" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20210309; h=Content-Transfer-Encoding: Content-Type:MIME-Version:Message-ID:Date:Subject:Cc:To:From:Sender:Reply-To: Content-ID:Content-Description:In-Reply-To:References; bh=X2vAk2Jq9L5dNEBtMuEUntil+Ke6M3OyswhQsebpvUE=; b=R3oRwHavtQnGWQOOjXuLJXkKHd WfmUf8yXMLRbGXKe/+veBABRIgGniAqspkruHm9uJD1f45/5NwbRE5FT59GAwVcOj8ji4uI2HTw8I ZmmYx5lT7xHtIV7oA23Rogx7jqzj1lVtF4NIOn1SSaELwtv03mVFEb2oYdCS7BeBSFfR4Gu7EvVEz xBvWk9+nxbrbDKciq3kPPMLi0FQI8sLSQ/fCJGj7hVQ7LcJmZ+npp8zKA9msoNSicA2/xt/1La5CX 0LGyBGR+rQN0bfI7NUQE26Q6XFxft42wFhzztLFxi0Sc+G0xHb1PjmegS0J2j7oNqTxPZC+RSw4w9 L262T6UQ==; Received: from [50.53.2.24] (helo=bombadil.infradead.org) by bombadil.infradead.org with esmtpsa (Exim 4.98 #2 (Red Hat Linux)) id 1tHIZK-00000001bnv-2tkA; Sat, 30 Nov 2024 08:11:10 +0000 From: Randy Dunlap To: linux-kernel@vger.kernel.org Cc: Randy Dunlap , Sebastian Fricke , Jonathan Corbet , linux-doc@vger.kernel.org, Johannes Berg , Greg Kroah-Hartman , workflows@vger.kernel.org Subject: [PATCH] docs: debugging: add more info about devcoredump Date: Sat, 30 Nov 2024 00:11:06 -0800 Message-ID: <20241130081107.552503-1-rdunlap@infradead.org> X-Mailer: git-send-email 2.47.1 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Correct a few small things in the devcoredump synopsis and then add the devcoredump APIs to it. Fixes: a037699da0a1 ("docs: Add debugging section to process") Signed-off-by: Randy Dunlap Cc: Sebastian Fricke Cc: Jonathan Corbet Cc: linux-doc@vger.kernel.org Cc: Johannes Berg Cc: Greg Kroah-Hartman Cc: workflows@vger.kernel.org --- Documentation/process/debugging/driver_development_debugging_guide.rst | = 20 ++++++++-- 1 file changed, 16 insertions(+), 4 deletions(-) --- linux-next-20241125.orig/Documentation/process/debugging/driver_develop= ment_debugging_guide.rst +++ linux-next-20241125/Documentation/process/debugging/driver_development_= debugging_guide.rst @@ -207,17 +207,29 @@ resources, that can cause performance di device coredump --------------- =20 -Prerequisite: ``#include `` +Prerequisite: ``CONFIG_DEV_COREDUMP`` & ``#include `` =20 Provides the infrastructure for a driver to provide arbitrary data to user= land. It is most often used in conjunction with udev or similar userland applica= tion to listen for kernel uevents, which indicate that the dump is ready. Udev = has rules to copy that file somewhere for long-term storage and analysis, as by -default, the data for the dump is automatically cleaned up after 5 minutes. -That data is analyzed with driver-specific tools or GDB. +default, the data for the dump is automatically cleaned up after a default +5 minutes. That data is analyzed with driver-specific tools or GDB. + +A device coredump can be created with a vmalloc area, with read/free +methods, or as a scatter/gather list. =20 You can find an example implementation at: `drivers/media/platform/qcom/venus/core.c -`__ +`__, +in the Bluetooth HCI layer, in several wireless drivers, and in several +DRM drivers. + +devcoredump interfaces +~~~~~~~~~~~~~~~~~~~~~~ + +.. kernel-doc:: include/linux/devcoredump.h + +.. kernel-doc:: drivers/base/devcoredump.c =20 **Copyright** =C2=A92024 : Collabora