From mboxrd@z Thu Jan 1 00:00:00 1970 From: Christian Borntraeger Subject: Re: [PATCH 1/2] KVM: provide irq_unsafe kvm_guest_{enter|exit} Date: Thu, 30 Apr 2015 14:07:38 +0200 Message-ID: <55421B0A.2060606@de.ibm.com> References: <1430394211-25209-1-git-send-email-borntraeger@de.ibm.com> <1430394211-25209-2-git-send-email-borntraeger@de.ibm.com> <554216EC.6070406@redhat.com> <554219A1.8050006@de.ibm.com> <554219F2.9020805@de.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Cc: linux-mips@linux-mips.org, KVM , kvm-ppc@vger.kernel.org, Cornelia Huck , kvmarm@lists.cs.columbia.edu To: Paolo Bonzini Return-path: In-Reply-To: <554219F2.9020805@de.ibm.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: kvmarm-bounces@lists.cs.columbia.edu Sender: kvmarm-bounces@lists.cs.columbia.edu List-Id: kvm.vger.kernel.org Am 30.04.2015 um 14:02 schrieb Christian Borntraeger: > Am 30.04.2015 um 14:01 schrieb Christian Borntraeger: >> Am 30.04.2015 um 13:50 schrieb Paolo Bonzini: >>> >>> >>> On 30/04/2015 13:43, Christian Borntraeger wrote: >>>> +/* must be called with irqs disabled */ >>>> +static inline void __kvm_guest_enter(void) >>>> { >>>> - unsigned long flags; >>>> - >>>> - BUG_ON(preemptible()); >>> >>> Please keep the BUG_ON() in kvm_guest_enter. Otherwise looks good, thanks! > > Ah, you mean have the BUG_ON in the non underscore version? Yes, makes sense. Hmmm, too quick. the BUG_ON was there to make sure that rcu_virt_note_context_switch is safe. The reworked code pulls the rcu_virt_note_context_switch within the irq_save section so we no longer need this BUG_ON, no? Christian