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From:   Amir Goldstein <amir73il@gmail.com>
Date:   Mon, 17 Sep 2018 13:53:48 +0300
Message-ID: <CAOQ4uxiBMD7ZRVz=iiY9bUEmvQOYSqz7wWxMQvwj7EpAd-ft1A@mail.gmail.com>
Subject: Re: [PATCH] fanotify support save thread id
To:     nixiaoming@huawei.com
Cc:     Jan Kara <jack@suse.cz>,
        linux-fsdevel <linux-fsdevel@vger.kernel.org>,
        linux-kernel <linux-kernel@vger.kernel.org>,
        Steve Grubb <sgrubb@redhat.com>
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On Mon, Sep 17, 2018 at 1:02 PM nixiaoming <nixiaoming@huawei.com> wrote:
>
> Added FAN_EVENT_INFO_TID to select the thread id of the event trigger
>

Maybe "to report the thread id of the task that caused the event".
Also in commit title, I think "reporting thread id" is more to the point
than "save thread id".


> Signed-off-by: nixiaoming <nixiaoming@huawei.com>
> ---
> --- a/include/uapi/linux/fanotify.h
> +++ b/include/uapi/linux/fanotify.h
> @@ -18,6 +18,7 @@
>
>  #define FAN_ONDIR              0x40000000      /* event occurred against dir */
>
> +#define FAN_EVENT_INFO_TID     0x02000000      /* event save thread id replace tgid */
>  #define FAN_EVENT_ON_CHILD     0x08000000      /* interested in child events */
>

nixiaoming,

You misunderstood me.

I meant that you should add support for flag FAN_EVENT_INFO_TID
for the fanotify_init() syscall, not the fanotify_mark() syscall.

See this commit from Steve Grubb for example of adding new opt-in
behavior to fanotify:
de8cd83e91bc audit: Record fanotify access control decisions

BTW, Steve, did you ever follow up with a man-pages patch?

Thanks,
Amir.