Re: [PATCH v2 2/2] io_uring/timeout: immediate timeout arg

[Pavel Begunkov <asml.silence@gmail.com>]

On 2/27/26 14:08, Stefan Metzmacher wrote:
> Hi Pavel,
> 
>>       if (unlikely(req->flags & (REQ_F_FIXED_FILE | REQ_F_BUFFER_SELECT)))
>>           return -EINVAL;
>> @@ -460,10 +461,20 @@ int io_timeout_remove_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
>>               return -EINVAL;
>>           if (tr->flags & IORING_LINK_TIMEOUT_UPDATE)
>>               tr->ltimeout = true;
>> -        if (tr->flags & ~(IORING_TIMEOUT_UPDATE_MASK|IORING_TIMEOUT_ABS))
>> +        if (tr->flags & ~(IORING_TIMEOUT_UPDATE_MASK |
>> +                  IORING_TIMEOUT_ABS |
>> +                  IORING_TIMEOUT_IMMEDIATE_ARG))
>>               return -EINVAL;
>> -        if (get_timespec64(&tr->ts, u64_to_user_ptr(READ_ONCE(sqe->addr2))))
>> +
>> +        arg = READ_ONCE(sqe->addr2);
>> +        if (tr->flags & IORING_TIMEOUT_IMMEDIATE_ARG) {
>> +            if (tr->flags & IORING_TIMEOUT_ABS)
>> +                return -EINVAL;
>> +            tr->ts = ns_to_timespec64(arg);
> 
> I'm wondering if there is enough free space in a small sqe to hold a full timespec?
> So that there is no restriction for IORING_TIMEOUT_ABS...

Well, u64 gives ~500 years in ns, it should be fine to just
allow the abs mode. We just need to make sure to zero check
the unused fields in case it'd need to be extended.

-- 
Pavel Begunkov