Messages in this thread | | | From | Borislav Petkov <> | Subject | [PATCH -v4 0/2] printk.devkmsg: Ratelimit it by default | Date | Fri, 8 Jul 2016 11:18:48 +0200 |
| |
From: Borislav Petkov <bp@suse.de>
Hi all,
sorry for spamming so quickly again and not waiting for a week before resubmitting but I believe the stuff is ready for 4.8.
So here's v4 with all the minor review comments addressed.
Changelog: ----------
v3:
here's v3 integrating Ingo's comments. The thing is called printk.devkmsg= or printk_devkmsg now, depending on cmdline option or sysctl.
v2:
here's v2 with the requested sysctl option kernel.printk_kmsg and locking of the setting when printk.kmsg= is supplied on the command line.
Patch 1 is unchanged.
Patch 2 has grown the sysctl addition.
v1:
Rostedt is busy so I took Linus' old patch and Steven's last v2 and split and extended them with the comments people had on the last thread:
https://lkml.kernel.org/r/20160425145606.598329f2@gandalf.local.home
I hope, at least.
So it is ratelimiting by default, with "on" and "off" cmdline options. I called the option somewhat a bit shorter too: "printk.kmsg"
The current use cases of this and of which I'm aware are:
* debug the kernel and thus shut up all interfering input from userspace, i.e. boot with "printk.kmsg=off"
* debug userspace (and by that I mean systemd) by booting with "printk.kmsg=on" so that the ratelimiting is disabled and the kernel log gets all the spew.
Thoughts?
Please queue, thanks.
Borislav Petkov (2): ratelimit: Extend to print suppressed messages on release printk: Add kernel parameter to control writes to /dev/kmsg
Documentation/kernel-parameters.txt | 6 +++ Documentation/sysctl/kernel.txt | 14 ++++++ include/linux/printk.h | 7 +++ include/linux/ratelimit.h | 38 +++++++++++++--- kernel/printk/printk.c | 86 +++++++++++++++++++++++++++++++++---- kernel/sysctl.c | 9 ++++ lib/ratelimit.c | 10 +++-- 7 files changed, 153 insertions(+), 17 deletions(-)
-- 2.7.3
| |