Re: [PATCH bpf] ftrace: Add missing ftrace_lock to update_ftrace_direct_add/del

[Alexei Starovoitov]

On Mon, Mar 2, 2026 at 12:16 AM Jiri Olsa <jolsa@xxxxxxxxxx> wrote:
>
> Ihor and Kumar reported splat from ftrace_get_addr_curr [1], which happened
> because of the missing ftrace_lock in update_ftrace_direct_add/del functions
> allowing concurrent access to ftrace internals.
>
> The ftrace_update_ops function must be guarded by ftrace_lock, adding that.
>
> Fixes: 05dc5e9c1fe1 ("ftrace: Add update_ftrace_direct_add function")
> Fixes: 8d2c1233f371 ("ftrace: Add update_ftrace_direct_del function")
> Reported-by: Ihor Solodrai <ihor.solodrai@xxxxxxxxx>
> Reported-by: Kumar Kartikeya Dwivedi <memxor@xxxxxxxxx>
> Closes: https://lore.kernel.org/bpf/1b58ffb2-92ae-433a-ba46-95294d6edea2@xxxxxxxxx/
> Tested-by: Ihor Solodrai <ihor.solodrai@xxxxxxxxx>
> Signed-off-by: Jiri Olsa <jolsa@xxxxxxxxxx>

lgtm.

Steven,
should it land through ftrace tree?