From mboxrd@z Thu Jan  1 00:00:00 1970
From: Peter Zijlstra <peterz@infradead.org>
Subject: Re: [PATCH net-next v4 1/2] bpf/tracing: allow user space to query
 prog array on the same tp
Date: Tue, 12 Dec 2017 10:03:31 +0100
Message-ID: <20171212090331.umlkvftrm3helfww@hirez.programming.kicks-ass.net>
References: <20171211193903.2428317-1-yhs@fb.com>
 <20171211193903.2428317-2-yhs@fb.com>
Mime-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Cc: ast@fb.com, daniel@iogearbox.net, netdev@vger.kernel.org,
        kernel-team@fb.com
To: Yonghong Song <yhs@fb.com>
Return-path: <netdev-owner@vger.kernel.org>
Received: from merlin.infradead.org ([205.233.59.134]:57510 "EHLO
        merlin.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org
        with ESMTP id S1750955AbdLLJDj (ORCPT
        <rfc822;netdev@vger.kernel.org>); Tue, 12 Dec 2017 04:03:39 -0500
Content-Disposition: inline
In-Reply-To: <20171211193903.2428317-2-yhs@fb.com>
Sender: netdev-owner@vger.kernel.org
List-ID: <netdev.vger.kernel.org>

On Mon, Dec 11, 2017 at 11:39:02AM -0800, Yonghong Song wrote:
> The usage:
>   struct perf_event_query_bpf *query = malloc(...);
>   query.ids_len = ids_len;
>   err = ioctl(pmu_efd, PERF_EVENT_IOC_QUERY_BPF, &query);

You didn't spot the fixes to your changelog ;-) The above should read
something like:

    struct perf_event_query_bpf *query =
        malloc(sizeof(*query) + sizeof(u32) * ids_len);
    query->ids_len = ids_len;
    err = ioctl(pmu_efd, PERF_EVENT_IOC_QUERY_BPF, query);