linux-kernel - Re: [PATCH v2 0/2] bpf, x86/unwind/orc: Support reliable unwinding through BPF stack frames

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

Message-ID: <aTGaVw005i8-Lb3L@krava>
Date: Thu, 4 Dec 2025 15:27:35 +0100
From: Jiri Olsa <olsajiri@...il.com>
To: Josh Poimboeuf <jpoimboe@...nel.org>
Cc: x86@...nel.org, linux-kernel@...r.kernel.org,
	live-patching@...r.kernel.org, bpf@...r.kernel.org,
	Andrey Grodzovsky <andrey.grodzovsky@...wdstrike.com>,
	Petr Mladek <pmladek@...e.com>, Song Liu <song@...nel.org>,
	Raja Khan <raja.khan@...wdstrike.com>,
	Miroslav Benes <mbenes@...e.cz>,
	Alexei Starovoitov <ast@...nel.org>,
	Daniel Borkmann <daniel@...earbox.net>,
	Andrii Nakryiko <andrii@...nel.org>,
	Peter Zijlstra <peterz@...radead.org>
Subject: Re: [PATCH v2 0/2] bpf, x86/unwind/orc: Support reliable unwinding
 through BPF stack frames

On Wed, Dec 03, 2025 at 07:32:14PM -0800, Josh Poimboeuf wrote:
> Fix livepatch stalls which may be seen when a task is blocked with BPF
> JIT on its kernel stack.
> 
> Changes since v1 (https://lore.kernel.org/cover.1764699074.git.jpoimboe@kernel.org):
> - fix NULL ptr deref in __arch_prepare_bpf_trampoline()
> 
> Josh Poimboeuf (2):
>   bpf: Add bpf_has_frame_pointer()
>   x86/unwind/orc: Support reliable unwinding through BPF stack frames
> 

tried with bpftrace and it seems to go over bpf_prog properly
in this case:

        bpf_prog_2beb79c650d605dd_fentry_bpf_testmod_bpf_kfunc_common_test_1+320
        bpf_trampoline_354334973728+60
        bpf_kfunc_common_test+9
        bpf_prog_f837cdd29a0519b9_test1+25
        trace_call_bpf+345
        kprobe_perf_func+76
        aggr_pre_handler+72
        kprobe_ftrace_handler+361
        drm_core_init+202
        bpf_fentry_test1+9
        bpf_prog_test_run_tracing+357
        __sys_bpf+2263
        __x64_sys_bpf+33
        do_syscall_64+134
        entry_SYSCALL_64_after_hwframe+118

Reviewed-by: Jiri Olsa <jolsa@...nel.org>

thanks,
jirka