On 02/06/2020 15:34, Pavel Begunkov wrote:
> Trying to use them with IORING_SETUP_IOPOLL:
>
> RIP: 0010:io_iopoll_getevents+0x111/0x5a0
> Call Trace:
> ? _raw_spin_unlock_irqrestore+0x24/0x40
> ? do_send_sig_info+0x64/0x90
> io_iopoll_reap_events.part.0+0x5e/0xa0
> io_ring_ctx_wait_and_kill+0x132/0x1c0
> io_uring_release+0x20/0x30
> __fput+0xcd/0x230
> ____fput+0xe/0x10
> task_work_run+0x67/0xa0
> do_exit+0x353/0xb10
> ? handle_mm_fault+0xd4/0x200
> ? syscall_trace_enter+0x18c/0x2c0
> do_group_exit+0x43/0xa0
> __x64_sys_exit_group+0x18/0x20
> do_syscall_64+0x60/0x1e0
> entry_SYSCALL_64_after_hwframe+0x44/0xa9
io_do_iopoll()
{
...
ret = kiocb->*ki_filp*->f_op->iopoll(kiocb, spin);
}
Hmm, I'll double check later that only read*/write* can be done
with IOPOLL, and send a follow-up patch if necessary.
>
> Also SQPOLL thread can't know which file table to use with
> open/close. Disallow all these cases.
>
> Signed-off-by: Pavel Begunkov <asml.silence@xxxxxxxxx>
> ---
> fs/io_uring.c | 8 ++++++++
> 1 file changed, 8 insertions(+)
>
> diff --git a/fs/io_uring.c b/fs/io_uring.c
> index 732ec73ec3c0..7208f91e9e77 100644
> --- a/fs/io_uring.c
> +++ b/fs/io_uring.c
> @@ -2990,6 +2990,8 @@ static int io_openat_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
> const char __user *fname;
> int ret;
>
> + if (unlikely(req->ctx->flags & (IORING_SETUP_IOPOLL|IORING_SETUP_SQPOLL)))
> + return -EINVAL;
> if (sqe->ioprio || sqe->buf_index)
> return -EINVAL;
> if (req->flags & REQ_F_FIXED_FILE)
> @@ -3023,6 +3025,8 @@ static int io_openat2_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
> size_t len;
> int ret;
>
> + if (unlikely(req->ctx->flags & (IORING_SETUP_IOPOLL|IORING_SETUP_SQPOLL)))
> + return -EINVAL;
> if (sqe->ioprio || sqe->buf_index)
> return -EINVAL;
> if (req->flags & REQ_F_FIXED_FILE)
> @@ -3373,6 +3377,8 @@ static int io_fadvise(struct io_kiocb *req, bool force_nonblock)
>
> static int io_statx_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
> {
> + if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
> + return -EINVAL;
> if (sqe->ioprio || sqe->buf_index)
> return -EINVAL;
> if (req->flags & REQ_F_FIXED_FILE)
> @@ -3417,6 +3423,8 @@ static int io_close_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
> */
> req->work.flags |= IO_WQ_WORK_NO_CANCEL;
>
> + if (unlikely(req->ctx->flags & (IORING_SETUP_IOPOLL|IORING_SETUP_SQPOLL)))
> + return -EINVAL;
> if (sqe->ioprio || sqe->off || sqe->addr || sqe->len ||
> sqe->rw_flags || sqe->buf_index)
> return -EINVAL;
>
--
Pavel Begunkov
