From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Burakov, Anatoly" Subject: Re: [PATCH v2] malloc: notify primary process about hotplug in secondary Date: Mon, 10 Dec 2018 10:49:05 +0000 Message-ID: <0f7b6cfb-e7d0-b511-b943-7f1b3b3eda2f@intel.com> References: <20181204170610.250124-1-seth.howell@intel.com> <20181207201042.372870-1-seth.howell@intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Cc: dev@dpdk.org, stable@dpdk.org, Darek Stojaczyk To: Seth Howell Return-path: In-Reply-To: <20181207201042.372870-1-seth.howell@intel.com> Content-Language: en-US List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org Sender: "dev" On 07-Dec-18 8:10 PM, Seth Howell wrote: > When secondary process hotplugs memory, it sends a request > to primary, which then performs the real mmap() and sends > sync requests to all secondary processes. Upon receiving > such sync request, each secondary process will notify the > upper layers of hotplugged memory (and will call all > locally registered event callbacks). > > In the end we'll end up with memory event callbacks fired > in all the processes except the primary, which is a bug. > > This gets critical if memory is hotplugged while a VFIO > device is attached, as the VFIO memory registration - > which is done from a memory event callback present in the > primary process only - is never called. > > After this patch, a primary process fires memory event > callbacks before secondary processes start their > synchronizations - both for hotplug and hotremove. > > Fixes: 07dcbfe0101f ("malloc: support multiprocess memory hotplug") > > Signed-off-by: Seth Howell > Signed-off-by: Darek Stojaczyk > --- Lost my review tag... Reviewed-by: Anatoly Burakov -- Thanks, Anatoly