[systemd-devel] [PATCH] rules: Fix by-path of mmc RPMB partitions and don't blkid them

[Kay Sievers]

On Fri, Feb 13, 2015 at 10:35 AM, Martin Pitt <martin.pitt at ubuntu.com> wrote:
> Kay Sievers [2015-02-13 10:12 +0100]:
>> This looks awful. We should not litter generic rules with exotic niche
>> use cases like this. It will end up in a mess.
>
> Fully agreed :/
>
>> First, what is the use-case for by-path for mmc devices? If there is
>> no strong one, which I suspect, please just remove these rules again.
>
> At least with the current blacklist approach, this is the important
> bit:
>
> | -ENV{DEVTYPE}=="disk", ENV{ID_PATH}=="?*", SYMLINK+="disk/by-path/$env{ID_PATH}"
> | +ENV{DEVTYPE}=="disk", ENV{ID_PATH}=="?*", KERNEL!="mmcblk[0-9]*rpmb", SYMLINK+="disk/by-path/$env{ID_PATH}"
>
> i. e. this fixes /dev/disks/by-path/mumble sometimes pointing to
> /dev/mmcblk0 (correct) and sometimes pointing to /dev/mmcblk0rpmb
> (awfully wrong)

Sure, as long as we have the blacklist and not a whitelist, we can add
the rpmb devices to the current list at the top of the file.

> | +ENV{DEVTYPE}=="disk", ENV{ID_PATH}=="?*", KERNEL=="mmcblk[0-9]*rpmb", SYMLINK+="disk/by-path/$env{ID_PATH}-rpmb"
>
> This was more or less for completeness. I honestly don't know what to
> do with these devices, I'm happy if we drop that rule again.

Let's remove it. There was never a reason for by-path/ to cover all
exotic device types. disk/by-path/ is for slots, chassis, ports where
swappable disks can be connected and disconnected without the
identifier to change. I doubt that applies to mmc devices.

Kay