loader.efi: devinit() just after parsing args instead

c4640126f1160 ("loader.efi: Apply command-line DHCP overrides earlier")
was really good, but moving it just one statement earlier is even
better.  polarian on Libera describes a GELI setup on a system that
doesn't advertise a serial console via ConOut.  They don't have serial
input at the point that they would get prompted for the GELI passphrase,
but if we parse args just before devinit() then he can override the
console with `efibootmgr -e`.  This gives UEFI one advantage over BIOS
loader, as /boot.config isn't available to provide that kind of override
if your impediment is GELI.

We also considered reading loader.env earlier, but we have a chicken/egg
problem in that we must have probed for the ESP to be able to open() it.
We would instead need a devinit_early() and devinit_late() scheme that
allows GELI probing to be deferred until the later pass, after reading
loader.env to pick up the console override.  That's an idea I'd still
like to discuss because it's more robust than hoping that firmware won't
wipe out our efibootmgr(8) entries.

Tested by:	polarian on Libera
Reviewed by:	imp

(cherry picked from commit 78887369c47fda5707ef72ef46a1c903df5b7cae)

1 files changed, 6 insertions, 2 deletions

diff --git a/stand/efi/loader/main.c b/stand/efi/loader/main.c
index 4ff60e770113..7411f7b7c45c 100644
--- a/stand/efi/loader/main.c
+++ b/stand/efi/loader/main.c
@@ -1268,8 +1268,6 @@ main(int argc, CHAR16 *argv[])
 		    "failures\n", i);
 	}
 
-	devinit();
-
 	/*
 	 * Detect console settings two different ways: one via the command
 	 * args (eg -h) or via the UEFI ConOut variable.
@@ -1281,6 +1279,12 @@ main(int argc, CHAR16 *argv[])
 	howto &= ~RB_PROBE;
 
 	/*
+	 * We want to initialize after giving loader args a chance to elect a
+	 * different console than what we autodetect.
+	 */
+	devinit();
+
+	/*
 	 * Read additional environment variables from the boot device's
 	 * "LoaderEnv" file. Any boot loader environment variable may be set
 	 * there, which are subtly different than loader.conf variables. Only