On Wed, Jun 24, 2020 at 9:37 PM Abhinav Singh
<singhabhinav0796(a)gmail.com> wrote:
I m facing some issue while doing dynamic debug with rbd kernel
steps:
1. sudo cat /boot/config-`uname -r` | grep DYNAMIC_DEBUG
CONFIG_DYNAMIC_DEBUG=y
2.sudo mount -t debugfs none /sys/kernel/debug
3.sudo echo 9 > /proc/sysrq-trigger
This step is not strictly necessary, but since you've listed it,
you need to use "sudo tee" here as well. Otherwise this command
would fail with "Permission denied" because the shell would process
the redirect to /proc/sysrq-trigger before running "sudo echo 9".
4.sudo echo 'module rbd +p' | sudo tee -a
/sys/kernel/debug/dynamic_debug/control
Use "sudo tee" instead of "sudo tee -a", i.e. don't try to append
instead of overwriting. sudo before echo is bogus for the reason
mentioned above.
To summarize, you need:
$ echo 9 | sudo tee /proc/sysrq-trigger
$ echo 'module rbd +p' | sudo tee /sys/kernel/debug/dynamic_debug/control
Thanks,
Ilya