| 1 |
On Tue, Dec 18, 2012 at 6:07 PM, Neil Bothwick <neil@××××××××××.uk> wrote: |
| 2 |
> On Tue, 18 Dec 2012 17:55:16 -0500, Michael Mol wrote: |
| 3 |
> |
| 4 |
>> > #2 already has a solution, it's called an init*. Other solutions exist |
| 5 |
>> > but none are as elegant as a throwaway temporary filesystem in RAM. |
| 6 |
>> |
| 7 |
>> I find virtually nothing elegant about a temporary filesystem in RAM. |
| 8 |
>> It duplicates code that already exists on the system, and it |
| 9 |
>> represents and additional maintenance step in system upgrades. It |
| 10 |
>> seems almost a given that if someone is keeping multiple kernel images |
| 11 |
>> on a system, they're not updating the initr* for each when binaries |
| 12 |
>> that would be found in each are upgraded or rebuilt. |
| 13 |
> |
| 14 |
> I don't use separate initr* files, the initramfs is built into the |
| 15 |
> kernel, using the latest versions of the tools installed at the time the |
| 16 |
> kernel was compiled. That gives a single bootable file that, if it works |
| 17 |
> now, should always work. Most changes to the component packages do not |
| 18 |
> affect the simple job they have to do to get a system ready to run init. |
| 19 |
|
| 20 |
Just because it runs, doesn't mean it "works." For example, let's say |
| 21 |
your network now requires an additional protocol for the host to |
| 22 |
operate properly. Or let's say there's a security vulnerability in |
| 23 |
some network-aware component in your initramfs. Or that some piece of |
| 24 |
automounter code is vulnerable to corrupted filesystems on flash |
| 25 |
drives. |
| 26 |
|
| 27 |
> |
| 28 |
>> In Debian, Ubuntu and others, this is handled by a post-install hook |
| 29 |
>> where the initr* image is rebuilt. To me, this honestly feels like a |
| 30 |
>> hack. In something like Gentoo, I'd rather see package placement |
| 31 |
>> driven by whether or not it will be needed to get all mount points |
| 32 |
>> mounted. If that means i18n databases under something like /boot/data, |
| 33 |
>> that seems reasonable. To me, the only cases where initr* feels like |
| 34 |
>> the right solution are things like netboot or booting from read-only |
| 35 |
> |
| 36 |
> Or / on LVM, or / on an encrypted filesystem. or any other requirement |
| 37 |
> for a filesystem that cannot be used without adding code to the kernel. |
| 38 |
|
| 39 |
/ on special filesystems is a good use case, yes. I should have said |
| 40 |
"/ from an unusual source." |
| 41 |
|
| 42 |
-- |
| 43 |
:wq |
Archives