Along similar lines as commit 9326638cbe ("kprobes, x86: Use NOKPROBE_SYMBOL()
instead of __kprobes annotation"), convert __kprobes annotation to either
NOKPROBE_SYMBOL() or nokprobe_inline. The latter forces inlining, in which case
the caller needs to be added to NOKPROBE_SYMBOL().
Also:
- blacklist arch_deref_entry_point(), and
- convert a few regular inlines to nokprobe_inline in lib/sstep.c
A key benefit is the ability to detect such symbols as being
blacklisted. Before this patch:
$ cat /sys/kernel/debug/kprobes/blacklist | grep read_mem
$ perf probe read_mem
Failed to write event: Invalid argument
Error: Failed to add events.
$ dmesg | tail -1
[ 3736.112815] Could not insert probe at _text+10014968: -22
After patch:
$ cat /sys/kernel/debug/kprobes/blacklist | grep read_mem
0xc000000000072b50-0xc000000000072d20 read_mem
$ perf probe read_mem
read_mem is blacklisted function, skip it.
Added new events:
(null):(null) (on read_mem)
probe:read_mem (on read_mem)
You can now use it in all perf tools, such as:
perf record -e probe:read_mem -aR sleep 1
$ grep " read_mem" /proc/kallsyms
c000000000072b50 t read_mem
c0000000005f3b40 t read_mem
$ cat /sys/kernel/debug/kprobes/list
c0000000005f3b48 k read_mem+0x8 [DISABLED]
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
[mpe: Minor change log formatting, fix up some conflicts]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
71f6e58e5e