On Mon, Jul 23, 2018 at 04:42:38PM -0700, Tadeusz Struk wrote: > On 07/23/2018 03:08 PM, Jason Gunthorpe wrote: > > On Mon, Jul 23, 2018 at 03:00:20PM -0700, Tadeusz Struk wrote: > >> On 07/23/2018 02:56 PM, Jason Gunthorpe wrote: > >>> The proposed patch doesn't clear the data_pending if the entire buffer > >>> is not consumed, so of course it is ABI breaking, that really isn't OK. > >> The data_pending will be cleared by the timeout handler if the user doesn't > >> read the response fully before the timeout expires. The is the same situation > >> if the user would not read the response at all. > > That causes write() to fail with EBUSY > > > > NAK from me on breaking the ABI like this > > What if we introduce this new behavior only for the non-blocking mode > as James suggested? Or do you have some other suggestions? I think you should do it entirely in userspace. But something sensible linked to O_NONBLOCK could be OK. Jason
