2014-10-02 13:05:33

by Tanya Brokhman

Subject: Re: [PATCH 1/4] UBI: Ensure that all fastmap work is done upon WL shutdown

Hi Richard,

On 9/30/2014 1:20 AM, Richard Weinberger wrote:
> ...otherwise the deferred work might run after datastructures
> got freed and corrupt memory.
>
> Signed-off-by: Richard Weinberger <[email protected]>
> ---
> drivers/mtd/ubi/wl.c | 3 +++
> 1 file changed, 3 insertions(+)
>
> diff --git a/drivers/mtd/ubi/wl.c b/drivers/mtd/ubi/wl.c
> index 20f491713..dc01b1f 100644
> --- a/drivers/mtd/ubi/wl.c
> +++ b/drivers/mtd/ubi/wl.c
> @@ -2029,6 +2029,9 @@ static void protection_queue_destroy(struct ubi_device *ubi)
> void ubi_wl_close(struct ubi_device *ubi)
> {
> dbg_wl("close the WL sub-system");
> +#ifdef CONFIG_MTD_UBI_FASTMAP
> + flush_work(&ubi->fm_work);

flush_work returns bool. It might be useful to print that value for
debugging.

> +#endif
> cancel_pending(ubi);
> protection_queue_destroy(ubi);
> tree_destroy(&ubi->used);
>

Thanks
Tanya Brokhman
--
Employee of Qualcomm Innovation Center, Inc.
Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum,
hosted by The Linux Foundation

2014-10-02 13:18:28

by Richard Weinberger

Subject: Re: [PATCH 1/4] UBI: Ensure that all fastmap work is done upon WL shutdown

Am 02.10.2014 15:05, schrieb Tanya Brokhman:
>> +#ifdef CONFIG_MTD_UBI_FASTMAP
>> + flush_work(&ubi->fm_work);
>
> flush_work returns bool. It might be useful to print that value for debugging.

Why would this be useful?
The sole purpose of this flush is having a barrier.
If flush_work() had to wait (returns true) for a pending work, fine.
If where was no work (returns false) to wait for, also fine. :)

Thanks,
//richard