On 12/11/21 02:50, Greg Kroah-Hartman wrote:

On Fri, Dec 10, 2021 at 09:29:41AM -0800, Bart Van Assche wrote:

quoted

(b) No other block layer sysfs attribute follows this encoding scheme.

Then follow what they do.  Do they have multiple values in a single
file?  If so, they are broken and we should change that.

Hi Greg,

The only other block layer sysfs attribute I know of that reports 
multiple values is the queue/scheduler attribute. Here is an example of 
the output that can be produced by reading that attribute:

# cat /sys/block/sda/queue/scheduler
[mq-deadline] kyber bfq none

I don't think that changing the behavior of that attribute is an option 
because that would break existing user space software, e.g. the 
https://github.com/osandov/blktests/ test suite.

Thanks,

Bart.