On 2/25/19 7:17 PM, Jan Kiszka wrote:
> On 05.02.19 12:20, Philippe Gerum via Xenomai wrote:
>> On 2/4/19 7:55 PM, Jan Kiszka wrote:
>>>> - * Release the lock while copying the data to
>>>> - * keep latency low.
>>>> + * We have to drop the lock while reading in
>>>> + * data, but we can't rollback on bad read
>>>> + * from user because some other thread might
>>>> + * have populated the memory ahead of our
>>>> + * write slot already: bluntly clear the
>>>> + * unavailable bytes on copy error.
>>>> */
>>>> cobalt_atomic_leave(s);
>>>> - ret = xnbufd_copy_to_kmem(rsk->bufmem + wroff, bufd, n);
>>>> - if (ret < 0)
>>>> - return ret;
>>>> + xret = xnbufd_copy_to_kmem(rsk->bufmem + wroff, bufd, n);
>>>> cobalt_atomic_enter(s);
>>>> - /*
>>>> - * In case we were preempted while copying the
>>>> - * message, we have to write the whole thing
>>>> - * again.
>>>> - */
>>>> - if (rsk->wrtoken != wrtoken) {
>>>> - xnbufd_reset(bufd);
>>>> - goto redo;
>>>> + if (xret < 0) {
>>>> + memset(rsk->bufmem + wroff + n - xret, 0, xret);
>>>
>>> This looks fishy, to the compiler and also to me.
>>>
>> Oh, well. Paste© blunder, the fix originates from a distinct
>> co-kernel implementation. I'll resubmit.
>>
>
> Did I get that update already? I don't think so.
>
You may want to check my local dev. tree. I generally don't send every
trivial change to a reviewed patch to the mailing list, but I'm
certainly maintaining a branch for you to pick from there:
https://lab.xenomai.org/xenomai-rpm.git/commit/?h=for-upstream/next&id=99dc7076ee757c2c82ffa6c58930388974808c09
--
Philippe.
