git: 2c26d77d989a - main - Remove /boot/efi from mtree, missed in 0b7472b3d8d2.

[Nathan Whitehorn]

On 3/3/21 10:38 AM, Warner Losh wrote:
>
>
> On Wed, Mar 3, 2021 at 7:13 AM Nathan Whitehorn 
> <nwhitehorn at freebsd.org <mailto:nwhitehorn at freebsd.org>> wrote:
>
>
>
>     On 3/3/21 9:05 AM, Brandon Bergren wrote:
>     > On Wed, Mar 3, 2021, at 6:53 AM, Rodney W. Grimes wrote:
>     >> What am I missing here?  One place I am being told this is run in
>     >> an environment that may not even be an EFI booted system, and in
>     >> another place it is being used as a test if something is mounted
>     >> on it, which should only be true on an EFI booted system.
>     > That the script in question is a generic script that runs as
>     part of bsdinstall on every platform and has to be universal.
>     >
>     > The actual *problem* here is that
>     usr.sbin/bsdinstall/scripts/bootconfig has a default case that is
>     >              *)          die "Unsupported arch $(uname -m) for
>     UEFI install"
>     >
>     > which then causes the main script to bail out, leaving the
>     system in a half-installed state.
>     >
>     > If that had just been an exit 0 this would have never been a
>     problem, I suppose.
>     >
>     > Before the original change that broke this, there was a check
>     that the script was not running on powerpc or mips platforms
>     before running the efi bits, but this got taken out.
>     >
>
>     Well, incidentally. The bootconfig script needs to know if there
>     is an
>     ESP it should configure, but the signalling mechanism (the
>     presence of
>     the ESP mount point) was being broken by mtree making that directory
>     unconditionally even on systems that don't use EFI. So then
>     bootconfig
>     tried to set it up, but failed later on, because there was no EFI
>     loader
>     to set up. The mtree change makes the ESP mount point only exist on
>     systems with an ESP.
>
>
> So you made a unilateral change, without discussion of the bigger 
> design, to something without even asking the original person who made 
> the change to mtree about it for what sounds like an obscure case in 
> the installer that could be solved in a different way? It's trivial 
> enough to look at the boot method sysctl and skip the EFI update if we 
> didn't boot EFI (and if by change that's not on all systems, it's easy 
> enough to add it on all systems). I have no notion about why that 
> wasn't considered, at least, before jumping in and taking people by 
> surprise.
>
> Next time, talk to people first. That's the whole point of having 
> review tools, mailing list and git blame.
>
> Warner

This method of testing was in the original review here posted on Feb. 
23: https://reviews.freebsd.org/D28897

The description of the test procedure you're objecting to was even in 
the summary! Then we had a discussion by email about the change to mtree 
on the committers list on Feb. 28 to resolve a bug affecting PowerPC in 
the patch reviewed and approved by you. I then waited several days and 
had a long thread for several days on the mailing list about the 
approach. coming up with this short patch -- again, as a bug fix to a 
reviewed approach.

We can change the logic -- that's fine! But, to paraphrase, the reason 
we have reviews is so people like you can look at the review and note 
these kinds of problems when they are reviewed, not after the commit 
goes in. There's a significant amount of whiplash when you do get 
patches reviewed, approved, and then the person who reviewed and 
approved them accuses you of "taking people by surprise".

The installer *does* mount the partition in advance, so checking whether 
there is a mounted file system is a perfectly reasonable test to do. We 
could also check fstab. I would like to understand what is actually 
wrong here first, though. Especially after this misfire -- which is 
problematic for reasons that are still not clear to me, since there are 
a number of standard directories in hier(7) not in mtree -- I want to 
make sure we actually do have consensus about what is changing and why.
-Nathan