From mboxrd@z Thu Jan 1 00:00:00 1970 From: julien.grall@citrix.com (Julien Grall) Date: Fri, 16 Oct 2015 16:45:55 +0100 Subject: [Xen-devel] xen,arm: enable cpu_hotplug In-Reply-To: References: <561EE3E5.2000105@citrix.com> <1444898398.1607.18.camel@citrix.com> Message-ID: <56211BB3.9020605@citrix.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On 16/10/15 16:41, Stefano Stabellini wrote: > It is possible to shut down cpu1 (psci->cpu_off, which pauses the vcpu) > but it is not possible to remove cpu1 without removing cpu2 first. > > If the user configures the target to be cpu 2-4, then shuts down cpu2, it > won't receive any interrupts any more. This is not a cpu-hotplug bug. > Maybe is a do_psci_cpu_off bug, which should be improved to handle this > case. It's neither a PSCI cpu off bug. It's a bug in our vGIC implementation. Regards, -- Julien Grall From mboxrd@z Thu Jan 1 00:00:00 1970 From: Julien Grall Subject: Re: [Xen-devel] xen,arm: enable cpu_hotplug Date: Fri, 16 Oct 2015 16:45:55 +0100 Message-ID: <56211BB3.9020605@citrix.com> References: <561EE3E5.2000105@citrix.com> <1444898398.1607.18.camel@citrix.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=m.gmane.org@lists.infradead.org To: Stefano Stabellini , Ian Campbell Cc: xen-devel@lists.xensource.com, linux-arm-kernel@lists.infradead.org List-Id: xen-devel@lists.xenproject.org On 16/10/15 16:41, Stefano Stabellini wrote: > It is possible to shut down cpu1 (psci->cpu_off, which pauses the vcpu) > but it is not possible to remove cpu1 without removing cpu2 first. > > If the user configures the target to be cpu 2-4, then shuts down cpu2, it > won't receive any interrupts any more. This is not a cpu-hotplug bug. > Maybe is a do_psci_cpu_off bug, which should be improved to handle this > case. It's neither a PSCI cpu off bug. It's a bug in our vGIC implementation. Regards, -- Julien Grall