linux-kernel - [RFC 00/10] ftrace,bpf: Use single direct ops for bpf trampolines

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Message-ID: <20250729102813.1531457-1-jolsa@kernel.org>
Date: Tue, 29 Jul 2025 12:28:03 +0200
From: Jiri Olsa <jolsa@...nel.org>
To: Steven Rostedt <rostedt@...nel.org>,
	Florent Revest <revest@...gle.com>,
	Mark Rutland <mark.rutland@....com>
Cc: bpf@...r.kernel.org,
	linux-kernel@...r.kernel.org,
	linux-trace-kernel@...r.kernel.org,
	linux-arm-kernel@...ts.infradead.org,
	Alexei Starovoitov <ast@...nel.org>,
	Daniel Borkmann <daniel@...earbox.net>,
	Andrii Nakryiko <andrii@...nel.org>,
	Menglong Dong <menglong8.dong@...il.com>
Subject: [RFC 00/10] ftrace,bpf: Use single direct ops for bpf trampolines

hi,
while poking the multi-tracing interface I ended up with just one
ftrace_ops object to attach all trampolines.

This change allows to use less direct API calls during the attachment
changes in the future code, so in effect speeding up the attachment.

However having just single ftrace_ops object removes direct_call
field from direct_call, which is needed by arm, so I'm not sure
it's the right path forward.

Mark, Florent,
any idea how hard would it be to for arm to get rid of direct_call field?

thougts? thanks,
jirka


---
Jiri Olsa (10):
      ftrace: Make alloc_and_copy_ftrace_hash direct friendly
      ftrace: Add register_ftrace_direct_hash function
      ftrace: Add unregister_ftrace_direct_hash function
      ftrace: Add modify_ftrace_direct_hash function
      ftrace: Export some of hash related functions
      ftrace: Use direct hash interface in direct functions
      bpf: Add trampoline ip hash table
      ftrace: Factor ftrace_ops ops_func interface
      bpf: Remove ftrace_ops from bpf_trampoline object
      Revert "ftrace: Store direct called addresses in their ops"

 include/linux/bpf.h           |   8 +-
 include/linux/ftrace.h        |  51 ++++++++++---
 kernel/bpf/trampoline.c       |  94 +++++++++++++-----------
 kernel/trace/ftrace.c         | 481 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++-----------------------------------------------
 kernel/trace/trace.h          |   8 --
 kernel/trace/trace_selftest.c |   5 +-
 6 files changed, 395 insertions(+), 252 deletions(-)