Re: News UBSAN warnings in aacraid

From: Meelis Roos
Date: Tue Nov 28 2017 - 08:05:50 EST


> I think this chunk would solve the problem and result in the
> same behavior as before:
>
> --- a/drivers/scsi/aacraid/commsup.c
> +++ b/drivers/scsi/aacraid/commsup.c
> @@ -2511,8 +2511,8 @@ int aac_command_thread(void *data)
> /* Synchronize our watches */
> if (((NSEC_PER_SEC - (NSEC_PER_SEC / HZ)) > now.tv_nsec)
> && (now.tv_nsec > (NSEC_PER_SEC / HZ)))
> - difference = (((NSEC_PER_SEC -
> now.tv_nsec) * HZ)
> - + NSEC_PER_SEC / 2) / NSEC_PER_SEC;
> + difference = HZ + HZ / 2 -
> + now.tv_nsec / (NSEC_PER_SEC / HZ);
> else {
> if (now.tv_nsec > NSEC_PER_SEC / 2)
> ++now.tv_sec;
>
> but I don't see why we add in half a second here. Any ideas?

I did not try to understand the details but I can confirm that this
patch makes the warnings go away.

--
Meelis Roos (mroos@xxxxxxxx)