Re: [PATCH 0/3] zram: Replace pr_* with dev_*

Sergey Senozhatsky
2015-08-07T00:04:46Z

On (08/07/15 00:03), Salah Triki wrote:
> This patchset replaces pr_* with dev_*. dev_* attach kernel messages to the right
> device. In addition, patchs 1 and 2 add to messages the values of variables that trigger
> errors.
>

Hi,

I'd prefer to leave the messages the way they are. Changing anything
visible to user space (api, eror codes, error messages, etc.) is a
very risky business. You change the format of error messages and it
smells like a big NO-NO.

'zram: Cannot initialise lzo compressing backend'
--> 'block zram0: Cannot initialise lzo compressing backend'

And there are even more dramatic changes:
"Cannot change max compression streams\n"
--> "Cannot change max compression streams to %d\n"

"Can't change algorithm for initialized device\n"
--> "Can't change algorithm to %s for initialized device\n"

People already can have scripts doing `grep "zram:"` on dmesg or
whatever. We cannot change this anymore.

This potentially breaks things in user space. So, I NACK the change
set. Thanks.

Minchan, any opinion?

-ss

> Salah Triki (3):
> zram: Replace pr_info with dev_info in max_comp_streams_store
> zram: Replace pr_info with dev_info in comp_algorithm_store
> zram: Replace pr_* with dev_*
>
> drivers/block/zram/zram_drv.c | 34 ++++++++++++++++++++--------------
> 1 file changed, 20 insertions(+), 14 deletions(-)
>
> --
> 1.9.1
>