Re: [PATCH v2] printk: Add a short description string to kmsg_dump()

From: Jocelyn Falempe
Date: Wed Jul 17 2024 - 07:14:23 EST



On 02/07/2024 14:26, Jocelyn Falempe wrote:
kmsg_dump doesn't forward the panic reason string to the kmsg_dumper
callback.
This patch adds a new struct kmsg_dump_detail, that will hold the
reason and description, and pass it to the dump() callback.

To avoid updating all kmsg_dump() call, it adds a kmsg_dump_desc()
function and a macro for backward compatibility.

I've written this for drm_panic, but it can be useful for other
kmsg_dumper.
It allows to see the panic reason, like "sysrq triggered crash"
or "VFS: Unable to mount root fs on xxxx" on the drm panic screen.

v2:
* Use a struct kmsg_dump_detail to hold the reason and description
pointer, for more flexibility if we want to add other parameters.
(Kees Cook)
* Fix powerpc/nvram_64 build, as I didn't update the forward
declaration of oops_to_nvram()

Signed-off-by: Jocelyn Falempe <jfalempe@xxxxxxxxxx>
---
arch/powerpc/kernel/nvram_64.c | 8 ++++----
arch/powerpc/platforms/powernv/opal-kmsg.c | 4 ++--
arch/um/kernel/kmsg_dump.c | 2 +-
drivers/gpu/drm/drm_panic.c | 4 ++--
drivers/hv/hv_common.c | 4 ++--
drivers/mtd/mtdoops.c | 2 +-
fs/pstore/platform.c | 10 +++++-----
include/linux/kmsg_dump.h | 22 +++++++++++++++++++---
kernel/panic.c | 2 +-
kernel/printk/printk.c | 11 ++++++++---
10 files changed, 45 insertions(+), 24 deletions(-)


[...]

I pushed it to drm-misc-next, with the whitespace change in kmsg_dump.h

Thanks all for your reviews and comments.

Best regards,

--

Jocelyn