From mboxrd@z Thu Jan 1 00:00:00 1970 From: Thomas Monjalon Subject: Re: [PATCH] examples/vm_power: fix app to respect max cpus Date: Sun, 04 Nov 2018 21:49:37 +0100 Message-ID: <3183438.eAJMS0E4RF@xps> References: <20181031115032.12010-1-david.hunt@intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7Bit Cc: dev@dpdk.org, lei.a.yao@intel.com, stable@dpdk.org To: David Hunt Return-path: In-Reply-To: <20181031115032.12010-1-david.hunt@intel.com> List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org Sender: "dev" 31/10/2018 12:50, David Hunt: > The vm_power_manager app was not respecting the POWER_MGR_MAX_CPUS > during initialisation, so if there were more CPUs than this value (64), > it would lead to buffer overruns of there were more then 64 cores in > the system. > > Added in a check during init and un-init to only initialise up to > lcore_id 63. > > This raises the question as to why not simply increase the value of > POWER_MGR_MAX_CPUS. Well, it's not that simple, as many of the APIs take > a uint64_t as a parameter for the core mask, and this will not work for > cores greater than 63. So some work needs to be done in the future to > remove this limitation. For now we'll fix the memory corruption. > > Also, the patch that this fixes says "allow greater than 64 cores" but > that's not across the entire application, it's only for the out-of-band > monitoring. I'll add a notice for an API change in the next release to > clean this up, i.e. depricate any API calls that use masks. > > Fixes: 6453b9284b64 ("examples/vm_power: allow greater than 64 cores") > > Signed-off-by: David Hunt + Cc: stable@dpdk.org Applied, thanks