[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <20130312043526.GA4668@in.ibm.com>
Date: Tue, 12 Mar 2013 10:05:27 +0530
From: Ananth N Mavinakayanahalli <ananth@...ibm.com>
To: Masami Hiramatsu <masami.hiramatsu.pt@...achi.com>
Cc: Ingo Molnar <mingo@...hat.com>, linux-kernel@...r.kernel.org,
Timo Juhani Lindfors <timo.lindfors@....fi>,
Pavel Emelyanov <xemul@...allels.com>,
Jiri Kosina <jkosina@...e.cz>,
Nadia Yvette Chambers <nyc@...omorphy.com>,
yrl.pp-manager.tt@...achi.com,
"David S. Miller" <davem@...emloft.net>
Subject: Re: [PATCH -tip ] [BUGFIX] kprobes: Move hash_64() into
.text.kprobe section
On Mon, Mar 11, 2013 at 11:22:33PM +0900, Masami Hiramatsu wrote:
> Beacuse hash_64() is called from the get_kprobe() inside
> int3 handler, kernel causes int3 recursion and crashes if
> kprobes user puts a probe on it.
>
> Usually hash_64() is inlined into caller function, but in
> some cases, it has instances by gcc's interprocedural
> constant propagation.
>
> This patch adds __kprobes tag on the hash_64() and moves
> all those instances into .text.kprobe section so that
> kprobes can refuse probing on the instances.
>
> I've ensured that all hash_64 instances moves to the
> address between __kprobes_text_start and __kprobes_text_end
> with this patch as below.
>
> ffffffff8138bea0 T __kprobes_text_start
> ffffffff8138bec0 t hash_64.constprop.8
> ffffffff8138ef98 t hash_64.constprop.26
> ffffffff8138efae t hash_64
> ffffffff8138f066 t hash_64.constprop.43
> ffffffff8138f649 t hash_64.constprop.25
> ffffffff8139103a t hash_64.constprop.77
> ffffffff81391050 t hash_64.constprop.24
> ffffffff81391066 t hash_64.constprop.40
> ffffffff8139107c t hash_64.constprop.15
> ffffffff81391092 T __kprobes_text_end
>
> Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@...achi.com>
> Reported-by: Timo Juhani Lindfors <timo.lindfors@....fi>
> Cc: "David S. Miller" <davem@...emloft.net>
> Cc: Nadia Yvette Chambers <nyc@...omorphy.com>
> Cc: Pavel Emelyanov <xemul@...allels.com>
> Cc: Jiri Kosina <jkosina@...e.cz>
> Cc: Ananth N Mavinakayanahalli <ananth@...ibm.com>
Acked-by: Ananth N Mavinakayanahalli <ananth@...ibm.com>
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists