On Sun, Dec 18, 2022 at 4:09 PM Andrei Matei <andreimatei1@...> wrote:

Hello iovisor friends,

I'm curious what my options are for running a BPF program once, immediately, in the virtual memory context of a particular (user space) process. For example, say I want to read the current value from a known virtual memory address in the process' space. I'm curious if there's an official answer or, short of that, tricks that people might have used.
What I want is similar in spirit to BPF_PROG_RUN, I think, except that I think I want my program type to be perf-event (and BPF_PROG_RUN doesn't seem to support this program type), and I want to also control specify which process I'm interested in.

I feel like one solution might be around sending a signal to the process I'm interested in and placing a uprobe somewhere on the signal handling path, but I'm not sure of a general way to do this. Any suggestion is most welcome.

Could you describe what prog is going to do?
Have you considered using a task iterator parametrized with a particular task?