Am 29.04.2015 um 16:46 schrieb Austin S Hemmelgarn: > On 2015-04-29 10:11, Harald Hoyer wrote: >> On 29.04.2015 16:04, Richard Weinberger wrote: >>> Am 29.04.2015 um 16:01 schrieb Harald Hoyer: >>>> On 29.04.2015 15:46, Richard Weinberger wrote: >>>>> Am 29.04.2015 um 15:38 schrieb Harald Hoyer: >>>>>> On 29.04.2015 15:33, Richard Weinberger wrote: >>>>>>> It depends how you define "beginning". To me an initramfs is a *very* >>>>>>> minimal >>>>>>> tool to prepare the rootfs and nothing more (no udev, no systemd, no >>>>>>> "mini distro"). >>>>>>> If the initramfs fails to do its job it can print to the console like >>>>>>> the kernel does if it fails >>>>>>> at a very early stage. >>>>>>> >>>>>> >>>>>> Your solution might work for your small personal needs, but not for our >>>>>> customers. >>>>> >>>>> Correct, I don't know your customers, all I know are my customers. :-) >>>>> >>>>> What feature do your customers need? >>>>> I mean, I fully agree with you that an initramfs must not fail silently >>>>> but how does dbus help there? If it fails to mount the rootfs there is not >>>>> much it can do. >>>>> >>>>> Thanks, >>>>> //richard >>>>> >>>> >>>> We don't handcraft the initramfs script for every our customers, therefore >>>> we >>>> have to generically support hotplug, persistent device names, persistent >>>> interface names, network connectivity in the initramfs, user input >>>> handling for >>>> passwords, fonts, keyboard layouts, fips, fsck, repair tools for file >>>> systems, >>>> raid assembly, LVM assembly, multipath, crypto devices, live images, iSCSI, >>>> FCoE, all kinds of filesystems with their quirks, IBM z-series support, >>>> resume >>>> from hibernation, […] >>> >>> This is correct. But which of these tools/features depend on dbus? >> >> I would love to add dbus support to all of them and use it, so I can connect >> them all more easily. No need for them to invent their own version of IPC, >> which can only be used by their own tool set. >> > Resume is built into the kernel, so no need for IPC there. Keymaps, fonts, > and fsck need no IPC either. FIPS related stuff should need no IPC. > Anything to do with the Device > Mapper and hotplug should just need uevents. While I can kind of see you > wanting to have lvmetad in the initramfs for use with LVM, I've seen all > kinds of reports of issues caused > by that. I can also kind of understand wanting some kind of unified IPC for > the netboot related stuff, DBus is still serious overkill for any of that > IMHO. As things stand > currently, the few things in that list that I know actually use IPC for > anything get by just fine (and much faster) using just UDS.
Even if dbus is really needed you can embed it into the initramfs. What you need is a good bootstrap procedure between dbus/systemd within the initramfs and the real rootfs. Thanks, //richard -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
