RE: [PATCH v2 0/4] perf probe, tracing/uprobes: Support probing at absolute address

[åæéå / HIRAMATUïMASAMI]

> From: Wang Nan [mailto:wangnan0@xxxxxxxxxx]
> 
> The goal of these 4 patches is to allow perf probing at absolute address
> for uprobes and kprobes. During the development several small problem in
> 'perf probe -l' is found and fixed.
> 
> Patch 1 has already acked by Masami Hiramatsu.
> 
> Patch 2 fixes a problem about zero address in perf side.
> 
> Patch 3 is the main patch of these 4. It allows following command:
> 
>  # perf probe /lib/x86_64-linux-gnu/libc-2.19.so 0xeb860
> 
>  Different from v1, no extra '+' is required.

Yeah, this seems better for me. Since '+' has double meanings "positive value" and
"add something", I think it's not good for this context.

> 
> Patch 4 is a kernel side patch which fixes a small problem in uprobe_event
> that, if address is 0, uprobe_events reports '0x  (null)'. It is independent
> from the other patches.

Oops, right.

Thanks!

> 
> Wang Nan (4):
>   perf probe: Prevent segfault when reading probe point with absolute
>     address
>   perf probe: Fix list result when address is zero
>   perf probe: Support probing at absolute address
>   tracing/uprobes: Do not print '0x  (null)' when offset is 0
> 
>  kernel/trace/trace_uprobe.c    |  17 +++-
>  tools/perf/util/probe-event.c  | 210 +++++++++++++++++++++++++++++++++++++----
>  tools/perf/util/probe-event.h  |   4 +
>  tools/perf/util/probe-finder.c |  21 +----
>  4 files changed, 216 insertions(+), 36 deletions(-)
> 
> --
> 1.8.3.4