On Mon, Feb 24, 2025 at 04:30:48PM -0700, Jens Axboe wrote: > On 2/24/25 2:31 PM, Keith Busch wrote: > > From: Keith Busch <kbusch@xxxxxxxxxx> > > > > There is already a field in io_kiocb that can store a registered buffer > > index, use that instead of stashing the value into struct io_nop. > > Only reason it was done this way is that ->buf_index is initially the > buffer group ID, and then the buffer ID when a buffer is selected. But I > _think_ we always restore that and hence we don't need to do this > anymore, should be checked. Maybe you already did? The IORING_OP_NOP opdef doesn't set the buffer_select flag, so the req buf_index couldn't be used for a buffer select id.