Re: [PATCH] scsi: message: fusion: Fix a possible data race in mpt_ioc_reset()

Bart Van Assche
2023-10-24T19:03:45Z

On 10/24/23 00:27, Tuo Li wrote:
> In my opinion, this may be a harmful race, because the value of
> ioc->taskmgmt_quiesce_io can be rewritten by mpt_ioc_reset() when
> another thread is accessing it.

It is a common pattern in the Linux kernel that a variable is set from
one thread without using locking and is read by another thread that is
holding a lock. It should be sufficient here to use WRITE_ONCE(). I
don't think that acquiring and releasing the spin lock is required.

Thanks,

Bart.