Mounting Rapid Storage Technology volumes?

Q&A
1

I would ordinarily use mdadm to do this (https://www.intel.com/content/dam/www/public/us/en/documents/white-papers/rst-linux-paper.pdf), but it seems to require /dev/mem

$ sudo cat /proc/mdstat
Personalities : [raid0] [raid1] [raid10]
unused devices: <none>

$ sudo mdadm --detail-platform
mdadm: imsm capabilities not found for controller

https://git.kernel.org/pub/scm/utils/mdadm/mdadm.git/tree/probe_roms.c#n104

which isn’t available on Clear. However, if I compile and use a modified kernel with CONFIG_DEVMEM=y, it works without any problems

$ sudo cat /proc/mdstat
Personalities : [raid0] [raid1] [raid10]
md124 : active (auto-read-only) raid1 sde[1] sdf[0]

$ sudo mdadm --detail-platform
Platform : Intel(R) Rapid Storage Technology

Is there a safer way?

Thanks!

2

[edit my memory refreshed]

/dev/mem is very dangerous and only should be used for debugging purposes. It grants processes access to all sorts of restricted memory and makes any sort of exploit exponentially easier.

3

As a workaround dmraid (Index of /~heinzm/sw/dmraid/src) doesn’t use /dev/mem and is able to assemble the RST volume I have into a mountable state on the current native kernel. Not sure if this will come with its own security problems due to its outdatedness or work with less simple stuff like VROC though. I’ll try to contact the MD RAID people and make a case for not relying on /dev/mem.

4

For anyone searching there is an open package request for dmraid on GitHub:

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