Re: dd hangs when reading large partitions

Bart Van Assche <bvanassche@xxxxxxx> · Sat, 19 Jan 2019 08:09:18 -0800

On 1/19/19 1:56 AM, Christoph Hellwig wrote:
On Fri, Jan 18, 2019 at 10:48:15AM -0700, Jens Axboe wrote:
It's UFS that totally buggy, if you look at its queuecommand, it does:

         if (!down_read_trylock(&hba->clk_scaling_lock))
                 return SCSI_MLQUEUE_HOST_BUSY;

UFS either needs to get fixed up, or we'll want a way to do something like
the below.

I think the right answer is to just revert the offending patch instead
of papering over it in the SCSI code.
.

Hi Christoph,

Which patch are you referring to?

Thanks,

Bart.