From 126437fc26be0629585f956b890e6314f56cd63b Mon Sep 17 00:00:00 2001 From: Randy Dunlap Date: Sat, 30 Nov 2024 00:11:06 -0800 Subject: docs: debugging: add more info about devcoredump 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 Signed-off-by: Jonathan Corbet Link: https://lore.kernel.org/r/20241130081107.552503-1-rdunlap@infradead.org --- .../debugging/driver_development_debugging_guide.rst | 20 ++++++++++++++++---- 1 file changed, 16 insertions(+), 4 deletions(-) diff --git a/Documentation/process/debugging/driver_development_debugging_guide.rst b/Documentation/process/debugging/driver_development_debugging_guide.rst index aef204094205..46becda8764b 100644 --- a/Documentation/process/debugging/driver_development_debugging_guide.rst +++ b/Documentation/process/debugging/driver_development_debugging_guide.rst @@ -207,17 +207,29 @@ resources, that can cause performance disruptions or even OOM kills. device coredump --------------- -Prerequisite: ``#include `` +Prerequisite: ``CONFIG_DEV_COREDUMP`` & ``#include `` Provides the infrastructure for a driver to provide arbitrary data to userland. It is most often used in conjunction with udev or similar userland application 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. 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 **Copyright** ©2024 : Collabora -- cgit v1.2.3