Re: [PATCH 0/2] ublk: fix race between io_uring_cmd_complete_in_task and ublk_cancel_cmd

[Jared Holzman <jholzman@nvidia.com>]

On 23/04/2025 12:24, Ming Lei wrote:
> Hello Jens,
> 
> The 2 patches try to fix race between between io_uring_cmd_complete_in_task
> and ublk_cancel_cmd, please don't apply until Jared verifies them.
> 
> Jared, please test and see if the two can fix your crash issue on v6.15-rc3.
> 
> If you can't reproduce it on v6.15-rc3, please backport them to v6.14, and I
> can help the backport if you need.
> 
> Thanks,
> Ming
> 
> Ming Lei (2):
>   ublk: call ublk_dispatch_req() for handling UBLK_U_IO_NEED_GET_DATA
>   ublk: fix race between io_uring_cmd_complete_in_task and
>     ublk_cancel_cmd
> 
>  drivers/block/ublk_drv.c | 51 ++++++++++++++++++++++++++--------------
>  1 file changed, 34 insertions(+), 17 deletions(-)
> 

Hi Ming,

It's a solid fix. I ran it through our automation and it passed 300 iterations without an issue. Previously we were getting crash after less than 20.

I also back-ported the patches to 6.14 and it works there too.

Will these fixes make it into 6.15? Or only 6.16?

Also is there a 6.14 maintenance branch that could also be fixed or is it end-of-life already?

Thanks for the help on this.

Regards,

Jared.