Re: [linus:master] [eventfs] 852e46e239: BUG:unable_to_handle_page_fault_for_address

From: Steven Rostedt
Date: Mon Jan 29 2024 - 18:15:30 EST


On Mon, 29 Jan 2024 17:47:32 -0500
Steven Rostedt <rostedt@xxxxxxxxxxx> wrote:

> > And I hope there aren't any other stupid things I missed like that.
>
> Well the preliminary tests pass with this added to your patch:

Spoke too soon. The later tests started failing.

It fails on creating a kprobe, deleting it, and then recreating it. Even
though the directory is there, it can't be accessed.

# cd /sys/kernel/tracing

// Create a kprobe

# echo 'p:sched schedule' >> kprobe_events
# ls events/kprobes/
enable filter sched

// Now delete the kprobe

# echo '-:sched schedule' >> kprobe_events

// Make sure it's gone

# ls events/kprobes/
ls: cannot access 'events/kprobes/': No such file or directory

// Recreate it

# echo 'p:sched schedule' >> kprobe_events
# ls events/kprobes/
ls: cannot access 'events/kprobes/': No such file or directory
# ls events | grep kprobes
kprobes

No longer able to access it.

# ls -l events | grep kprobes
ls: cannot access 'events/kprobes': No such file or directory
d????????? ? ? ? ? ? kprobes


-- Steve