Re: [PATCH v11 04/11] tracing: wprobe: Add watchpoint probe event based on hardware breakpoint

On Wed, Aug 05, 2026 at 09:06:29PM -0400, Steven Rostedt wrote:

On Wed, 5 Aug 2026 21:39:09 +0200
Peter Zijlstra [off-list ref] wrote:

quoted

quoted

quoted

This seems limited to kernel addresses only? Should not also userspace
addresses be supported?  

Hmm, how would that work? The address is global for all tasks, so if you
add a user space address, what task would that be for? The one writing the
probe?  

Schedule the watchpoint along with the task of course. Given there is
breakpoint/perf integration this should be trivial.

I meant, what task is it attached to? Usually the way a probe works is to
create the probe and then enable it.

 # cd /sys/kernel/tracing
 # echo 'w:my_jiffies w@jiffies:8 value=+0($addr)' >> dynamic_events
 # echo 1 > events/wprobes/my_jiffies/enable

If the address is in user space, which task would that address be for?

What would the API look like? Should we add a pid to that for a specific task?

Same as uprobes?