Re: [RFC PATCH v2 2/2] s390x: Implement the USER_SIGP_BUSY capability

2021-11-04 Thread David Hildenbrand
>> >> Can't we call s390_cpu_reset_sigp_busy() directly from >> handle_sigp_single_dst(), >> after the handle_sigp_single_dst() call? > > Can I? Most of the orders in that routine are invoked via > "run_on_cpu(CPU(dst_cpu), ..." dispatching them to other vcpus, so I > presumed that was a stacked

Re: [RFC PATCH v2 2/2] s390x: Implement the USER_SIGP_BUSY capability

2021-11-04 Thread Eric Farman
On Thu, 2021-11-04 at 09:23 +0100, David Hildenbrand wrote: > On 02.11.21 21:11, Eric Farman wrote: > > With the USER_SIGP capability, the kernel will pass most (but not > > all) > > SIGP orders to userspace for processing. But that means that the > > kernel > > is unable to determine if/when the o

Re: [RFC PATCH v2 2/2] s390x: Implement the USER_SIGP_BUSY capability

2021-11-04 Thread David Hildenbrand
On 02.11.21 21:11, Eric Farman wrote: > With the USER_SIGP capability, the kernel will pass most (but not all) > SIGP orders to userspace for processing. But that means that the kernel > is unable to determine if/when the order has been completed by userspace, > and could potentially return an inco

[RFC PATCH v2 2/2] s390x: Implement the USER_SIGP_BUSY capability

2021-11-02 Thread Eric Farman
With the USER_SIGP capability, the kernel will pass most (but not all) SIGP orders to userspace for processing. But that means that the kernel is unable to determine if/when the order has been completed by userspace, and could potentially return an incorrect answer (CC1 with status bits versus CC2