Re: [PATCH v2 tip/perf] uprobes: avoid false lockdep splat in uprobe timer callback

[Oleg Nesterov]

On 04/04, Andrii Nakryiko wrote:
>
> Also, point out in the comments more explicitly why we use seqcount
> despite our reader side being rather simple and never retrying. We favor
> well-maintained kernel primitive in favor of open-coding our own memory
> barriers.
>
> Link: https://lore.kernel.org/bpf/CAADnVQLLOHZmPO4X_dQ+cTaSDvzdWHzA0qUqQDhLFYL3D6xPxg@xxxxxxxxxxxxxx/
> Reported-by: Alexei Starovoitov <ast@xxxxxxxxxx>
> Suggested-by: Sebastian Siewior <bigeasy@xxxxxxxxxxxxx>
> Fixes: 8622e45b5da1 ("uprobes: Reuse return_instances between multiple uretprobes within task")
> Signed-off-by: Andrii Nakryiko <andrii@xxxxxxxxxx>

LGTM. FWIW,

Acked-by: Oleg Nesterov <oleg@xxxxxxxxxx>