Re: [PATCH v3] perf/core: fix mlock accounting in perf_mmap()

[Alexander Shishkin]

Song Liu <songliubraving@xxxxxx> writes:

> Eecreasing sysctl_perf_event_mlock between two consecutive perf_mmap()s of

Typo: "Decreasing".

> a perf ring buffer may lead to an integer underflow in locked memory
> accounting. This may lead to the undesired behaviors, such as failures in
> BPF map creation.
>
> Address this by adjusting the accounting logic to take into account the
> possibility that the amount of already locked memory may exceed the
> current limit.
>
> Fixes: c4b75479741c ("perf/core: Make the mlock accounting simple again")
> Signed-off-by: Song Liu <songliubraving@xxxxxx>
> Suggested-by: Alexander Shishkin <alexander.shishkin@xxxxxxxxxxxxxxx>
> Cc: Alexander Shishkin <alexander.shishkin@xxxxxxxxxxxxxxx>
> Cc: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
> Cc: Jiri Olsa <jolsa@xxxxxxxxxx>
> Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>

Other than that,

Acked-by: Alexander Shishkin <alexander.shishkin@xxxxxxxxxxxxxxx>

Thanks,
--
Alex