From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751618AbdITGrm (ORCPT ); Wed, 20 Sep 2017 02:47:42 -0400 Received: from LGEAMRELO12.lge.com ([156.147.23.52]:55043 "EHLO lgeamrelo12.lge.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751468AbdITGrl (ORCPT ); Wed, 20 Sep 2017 02:47:41 -0400 X-Original-SENDERIP: 156.147.1.125 X-Original-MAILFROM: minchan@kernel.org X-Original-SENDERIP: 10.177.220.163 X-Original-MAILFROM: minchan@kernel.org Date: Wed, 20 Sep 2017 15:47:39 +0900 From: Minchan Kim To: Sergey Senozhatsky Cc: Andrew Morton , linux-kernel@vger.kernel.org, Sergey Senozhatsky Subject: Re: [PATCH] zsmalloc: calling zs_map_object() from irq is a bug Message-ID: <20170920064739.GA11000@bbox> References: <20170920063941.14662-1-sergey.senozhatsky@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20170920063941.14662-1-sergey.senozhatsky@gmail.com> User-Agent: Mutt/1.5.24 (2015-08-30) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Sep 20, 2017 at 03:39:41PM +0900, Sergey Senozhatsky wrote: > Use BUG_ON(in_interrupt()) in zs_map_object(). Calling this > function from IRQ is a bug, because we use per-CPU mappings > and interrupt may corrupt those buffers. > > Signed-off-by: Sergey Senozhatsky IMHO, corruption the buffer would be not enough to be a BUG_ON which stop the system fully so user loses any chances to shut down smooth/hunt it down. More serious thing of our case is that it can leak other user's data by overwriting, which is more concern I am thinking now. So, Acked-by: Minchan Kim Thanks!