Russell, On Fri, Apr 29, 2016 at 12:57 PM, Russell King - ARM Linux <linux@xxxxxxxxxxxxxxxx> wrote: >> * Presumably on a PC you've got an extra bit in the middle (like grub >> or something like that) that can help you resolve your UUIDs even if >> you get your kernel from somewhere else. > > You are over-estimating what grub does. Grub doesn't resolve UUIDs at > all. Grub just passes the kernel arguments in its configuration file > for the entry it is booting to the kernel. It's a static configuration > found in /boot/grub/grub.conf. > > It doesn't probe devices for UUIDs. OK. The point was: if folks on PCs have a workflow that works for them, wonderful. That workflow doesn't work so great for me. My workflow doesn't hurt them. Why is it bad? >> * Presumably in the non-embedded world kernel hackers have a different >> workflow. They probably don't swap between different devices with >> different configurations on an hourly basis. They're not in the habit >> of totally reimaging their system periodically. Etc. Trying to force >> the workflow of a PC kernel hacker and an embedded kernel hacker to be >> the same doesn't seem like a worthwhile goal. > > In _my_ world with the "embedded" devices I have, I mount by UUID on > platforms which have multiple MMC devices to avoid exactly the problem > you're having. This works fine. > > If I were to switch the SD card, and I wanted to avoid changing the > boot loader configuration, I'd use label instead, and I'd label all > the SD card rootfs using the same label so I could just swap the cards. OK. The point was: if you have a workflow that works for you, wonderful. That workflow doesn't work so great for me. My workflow doesn't hurt you. Why is it bad? >> * Presumably an embedded kernel hacker running with ATA / SCSI could >> _usually_ assume that "sda" is his/her root filesystem. It's unlikely >> an embedded system would have more than one "sda" disk builtin and >> it's nearly guaranteed (I think) that a builtin ATA / SCSI controller >> would probe before any USB based devices. > > You've got a funny view again. N2100 has two hard disks. The clearfog > board from SolidRun has two mini-PCIe slots, each of which can have two > SATA interfaces... If you want to use it as a server-type platform with > lots of disks... OK. The point was: if you have a workflow that works for you, wonderful. That workflow doesn't work so great for me. My workflow doesn't hurt you. Why is it bad? >> Sure, if your root >> filesystem is USB based (really?) and you've got additional USB >> storage devices then you're SOL. Sorry. > > One of my Versatile Express platforms boots from USB, and has a MMC > slot... So this argument does not stack up. OK. The point was: if you have a workflow that works for you, wonderful. That workflow doesn't work so great for me. My workflow doesn't hurt you. Why is it bad? -Doug -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html