Re: [Xen-devel] [PATCH v2] xen/arm: implement GICD_I[S/C]ACTIVER reads

2020-03-30 Thread Julien Grall
Hi, On 27/03/2020 02:34, Stefano Stabellini wrote: It doesn't take into account the latest state of interrupts on other vCPUs. So I think your implementation is going to introduce a deadlock in the guest. Let's imagine a guest with 2 vCPUs (A and B) with the following setup: * The HW SP

Re: [Xen-devel] [PATCH v2] xen/arm: implement GICD_I[S/C]ACTIVER reads

2020-03-30 Thread Julien Grall
Hi Stefano, On 30/03/2020 17:35, Stefano Stabellini wrote: On Sat, 28 Mar 2020, Julien Grall wrote: qHi Stefano, On 27/03/2020 02:34, Stefano Stabellini wrote: This is a simple implementation of GICD_ICACTIVER / GICD_ISACTIVER reads. It doesn't take into account the latest state of interrupts

Re: [Xen-devel] [PATCH v2] xen/arm: implement GICD_I[S/C]ACTIVER reads

2020-03-30 Thread Stefano Stabellini
On Sat, 28 Mar 2020, Julien Grall wrote: > qHi Stefano, > > On 27/03/2020 02:34, Stefano Stabellini wrote: > > This is a simple implementation of GICD_ICACTIVER / GICD_ISACTIVER > > reads. It doesn't take into account the latest state of interrupts on > > other vCPUs. Only the current vCPU is up-t

Re: [Xen-devel] [PATCH v2] xen/arm: implement GICD_I[S/C]ACTIVER reads

2020-03-28 Thread Julien Grall
qHi Stefano, On 27/03/2020 02:34, Stefano Stabellini wrote: This is a simple implementation of GICD_ICACTIVER / GICD_ISACTIVER reads. It doesn't take into account the latest state of interrupts on other vCPUs. Only the current vCPU is up-to-date. A full solution is not possible because it would