From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Michael S. Tsirkin" Subject: Re: [dm-devel] [PATCH v5] fault-injection: introduce kvmalloc fallback options Date: Thu, 26 Apr 2018 21:49:19 +0300 Message-ID: <20180426214011-mutt-send-email-mst__22831.608184106$1524768461$gmane$org@kernel.org> References: <1524694663.4100.21.camel@HansenPartnership.com> <20180426125817.GO17484@dhcp22.suse.cz> <1524753932.3226.5.camel@HansenPartnership.com> <1524756256.3226.7.camel@HansenPartnership.com> <20180426184845-mutt-send-email-mst@kernel.org> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: virtualization-bounces@lists.linux-foundation.org Errors-To: virtualization-bounces@lists.linux-foundation.org To: Mikulas Patocka Cc: eric.dumazet@gmail.com, netdev@vger.kernel.org, Randy Dunlap , linux-kernel@vger.kernel.org, Matthew Wilcox , Michal Hocko , James Bottomley , linux-mm@kvack.org, dm-devel@redhat.com, Vlastimil Babka , David Rientjes , Andrew Morton , virtualization@lists.linux-foundation.org, David Miller , edumazet@google.com List-Id: virtualization@lists.linuxfoundation.org On Thu, Apr 26, 2018 at 12:07:25PM -0400, Mikulas Patocka wrote: > > IIUC debug kernels mainly exist so people who experience e.g. memory > > corruption can try and debug the failure. In this case, CONFIG_DEBUG_SG > > will *already* catch a failure early. Nothing special needs to be done. > > The patch helps people debug such memory coprruptions (such as using DMA > API on the result of kvmalloc). That's my point. I don't think your patch helps debug any memory corruptions. With CONFIG_DEBUG_SG using DMA API already causes a BUG_ON, that's before any memory can get corrupted. -- MST