initrd/bin/kexec-select-boot.sh: combine fs+display markers, update legend

boot_marker() now reads both kexec_initrd_compat.txt (USB filesystem)
and kexec_fb_compat.txt (DRM/KMS display driver) and returns combined:
  [OK]   = both pass
  [!]    = either fails
  (blank) = unable to verify

build_legend() also checks fb compat file for [!] entries.
Legend: [OK]=ready (USB+display)  [!]=may fail  (blank)=unable to check

Author: tlaurion

doc/ux-patterns.md

@@ -452,21 +452,15 @@ menu to indicate whether the initramfs supports the USB filesystem:
 | Marker | Color | Meaning |
 |---|---|---|
 | `[OK]` | Green | Ready — USB filesystem and display driver both confirmed present |
-| `[!]` | Yellow | May fail — missing USB filesystem module or framebuffer driver |
-| (blank) | Default | Could not check — initrd has no loadable modules to inspect |
+| `[!]` | Yellow | May fail — missing USB filesystem module or display driver |
+| (blank) | Default | Unable to check — initrd has no loadable modules to inspect |
 
 A legend explaining these markers is shown once per session via NOTE.
-When all entries are ready, the legend is short.  When any entry has
-a `[!]` marker, the full legend explains both `[OK]` and `[!]`:
+When all entries pass both checks, the legend shows the short form.
+When any entry has a `[!]` marker, the full legend includes the warning:
 
-Legend (all ready):
 ```
-[OK]=ready  (blank)=could not check
-```
-
-Legend (issues found):
-```
-[OK]=ready  [!]=may fail after kexec  (blank)=could not check
+[OK]=ready (USB+display)  [!]=may fail  (blank)=unable to check
 ```
 NOTE: [OK]=ready (USB+display)  [!]=may fail after kexec  (blank)=could not check
 

initrd/bin/kexec-select-boot.sh

@@ -137,11 +137,13 @@ build_legend() {
 	local has_issues="n"
 	if [ -r "/tmp/kexec_initrd_compat.txt" ] && grep -qF '[!]' /tmp/kexec_initrd_compat.txt 2>/dev/null; then
 		has_issues="y"
+	elif [ -r "/tmp/kexec_fb_compat.txt" ] && grep -qF '[!]' /tmp/kexec_fb_compat.txt 2>/dev/null; then
+		has_issues="y"
 	fi
 	if [ "$has_issues" = "y" ]; then
-		printf '\033[0;32m[OK]\033[0m=ready  \033[1;33m[!]\033[0m=may fail after kexec  (blank)=could not check'
+		printf '\033[0;32m[OK]\033[0m=ready (USB+display)  \033[1;33m[!]\033[0m=may fail  (blank)=unable to check'
 	else
-		printf '\033[0;32m[OK]\033[0m=ready  (blank)=could not check'
+		printf '\033[0;32m[OK]\033[0m=ready (USB+display)  (blank)=unable to check'
 	fi
 }
 
@@ -293,30 +295,39 @@ parse_option() {
 	LOG "parse_option: name='$name' kernel='$kernel' initrd='$initrd' params='${params:0:80}...'"
 }
 
-# Return the initrd compat marker for the current entry's initrd.
-# Reads /tmp/kexec_initrd_compat.txt (written by Layer 1) for USB
-# filesystem support.  Framebuffer support is handled as a separate
-# warning before the menu — efifb/bochs are often built into the
-# kernel image and can't be reliably detected from the initrd alone.
+# Return the combined compat marker for the current entry's initrd.
+# Reads two Layer 1 compat files:
+#   /tmp/kexec_initrd_compat.txt  — USB filesystem support
+#   /tmp/kexec_fb_compat.txt     — DRM/KMS display driver (i915, etc.)
 #
-# Compat file format:
-#   initrd/relative/path [OK]
-#   other/initrd/path [!]
-#   (absent entries = zero modules, can't verify)
+# Combined result:
+#   [OK]   — BOTH filesystem AND display driver confirmed present
+#   [!]    — EITHER filesystem or display driver confirmed missing
+#   (blank) — cannot verify (no modules in initrd)
 #
-# Three states:
-#   [OK]   — USB filesystem module confirmed
-#   [!]    — initrd has modules but not the USB filesystem one
-#   (blank) — zero modules, can't verify (likely built into kernel)
+# When the fb compat file has no entry for this initrd (no modules),
+# the fs marker is returned alone.
 #
 # In CLI mode adds ANSI colors: green [OK], yellow [!].
 boot_marker() {
-	local m="" grn="" ylw="" rst=""
+	local m="" fb="" grn="" ylw="" rst=""
 	[ "$gui_menu" != "y" ] && { grn=$'\033[0;32m'; ylw=$'\033[1;33m'; rst=$'\033[0m'; }
 	if [ -n "$initrd" ] && [ -r "/tmp/kexec_initrd_compat.txt" ]; then
 		local ip=$(echo "$initrd" | sed 's|^/*||')
 		m=$(grep "^$ip " /tmp/kexec_initrd_compat.txt 2>/dev/null | head -1 | cut -d' ' -f2)
-		[ -n "$m" ] && LOG "boot_marker: initrd=$ip marker=$m" || LOG "boot_marker: initrd=$ip no compat entry"
+		[ -n "$m" ] && LOG "boot_marker: initrd=$ip fs=$m" || LOG "boot_marker: initrd=$ip no fs entry"
+		if [ -r "/tmp/kexec_fb_compat.txt" ]; then
+			fb=$(grep "^$ip " /tmp/kexec_fb_compat.txt 2>/dev/null | head -1 | cut -d' ' -f2)
+			[ -n "$fb" ] && LOG "boot_marker: initrd=$ip fb=$fb" || LOG "boot_marker: initrd=$ip no fb entry"
+			# Combine both
+			if [ "$m" = "[OK]" ] && [ "$fb" = "[OK]" ]; then
+				:  # both OK
+			elif [ "$m" = "[!]" ] || [ "$fb" = "[!]" ]; then
+				m="[!]"  # either missing
+			else
+				m=""  # can't verify
+			fi
+		fi
 		[ "$m" = "[OK]" ] && m="${grn}[OK]${rst}"
 		[ "$m" = "[!]" ] && m="${ylw}[!]${rst}"
 	fi