Messages in this thread | | | Date | Tue, 01 Apr 2014 23:46:33 +0200 | From | Stefan Agner <> | Subject | Re: [RFC 2/2] mmc: use SD/MMC host ID for block device name ID |
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Am 2014-04-01 22:47, Stephen Warren wrote: > That's not true. There's no guarantee that a device name/ID gets > released as soon as the SD card is removed; something might still have > it mounted for example. Yes. Also when booted there are other solutions to get static block device name (e.g. /dev/disk/by-path), but the problem at hand aims for a solution for the root file system.
Also, eMMC don't get removed, and those internal eMMC devices are the reason of this thread... (see cover letter)
> The correct solution here is to use filesystem or partition UUIDs to > identify the device/partition, not to attempt to assign static device IDs. Yes, I'm aware of that solution. However, when recreating the partition table, those UUIDs do change, which in turn needs a change of the kernel arguments. Of course, one can use scripts to work around this, but its easier to just boot from the block device at a given location (say eMMC, first partition). Then, using UUID is also not as fast as using a device name directly, since all block devices get scanned. This is not optimal when trying to optimize boot speed, but might be negligible. I actually never measured that.
There are the /dev/disk/by-path/ which aim at a similar goal, but those names are generated by udev. I'm open to suggestions solve this issue in a more fashionable way...
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