+ LKML ---------- Forwarded message ---------- From: Arend van Spriel <aspr...@gmail.com> Date: Tue, Jan 9, 2018 at 8:19 PM Subject: Re: [PATCH 0/2] sysfs: allow user-space request for devcoredump To: Greg Kroah-Hartman <gre...@linuxfoundation.org>
On Tue, Jan 9, 2018 at 7:46 PM, Greg Kroah-Hartman <gre...@linuxfoundation.org> wrote: > On Tue, Dec 19, 2017 at 11:03:20AM +0100, Arend van Spriel wrote: >> From: Arend van Spriel <aspr...@gmail.com> >> >> Since commit 833c95456a70 ("device coredump: add new device coredump class") >> device drivers have a unified way to provide binary data obtained from a >> failing_device to user-space. However, there may be use-cases in which the >> driver has no reason to obtain the data, but user-space wants to initiate >> it. This adds a coredump device attribute in sysfs when the driver bound to >> the device supports the newly added coredump driver callback. > > What driver is going to set this? I don't want to add new options to > the kernel that never get used, do you have a driver to use it? Hi Greg, After sending these patches I realized that was going to be your response, but decided to wait for it. Obviously there is a driver for which I would like to have an option to create a device coredump from user-space, ie. the brcm80211 drivers (maintained by my alter-ego ;-) ). I can post these patches again as RFC including the brcm80211 driver patches. Here a bit of background about this itch. A couple of other driver support their own coredump implementation, ie. not using dev_coredump class and some support user-space initiated coredump through debugfs. As that depends on a Kconfig option I looked for other solutions. At first I considered doing it in dev_coredump class itself by doing: # echo 0000:04:00.0 > /sys/class/devcoredump/trigger with 'trigger' being a new sysfs attribute for devcoredump. However, using the driver core turned out to be much simpler, but I am still open for other/better options. Regards, Arend