Add configure option to enable gfxpayload=keep dynamically

Set GRUB_GFXPAYLOAD_LINUX=keep unless it's known to be unsupported on
the current hardware.  See
https://blueprints.launchpad.net/ubuntu/+spec/packageselection-foundations-n-grub2-boot-framebuffer.

Author: Colin Watson <cjwatson@ubuntu.com>
Forwarded: no
Last-Update: 2019-05-25

Patch-Name: gfxpayload-dynamic.patch

configure.ac

@@ -1937,6 +1937,17 @@ else
 fi
 AC_SUBST([QUICK_BOOT])
 
+AC_ARG_ENABLE([gfxpayload-dynamic],
+              [AS_HELP_STRING([--enable-gfxpayload-dynamic],
+                              [use GRUB_GFXPAYLOAD_LINUX=keep unless explicitly unsupported on current hardware (default=no)])],
+              [], [enable_gfxpayload_dynamic=no])
+if test x"$enable_gfxpayload_dynamic" = xyes ; then
+  GFXPAYLOAD_DYNAMIC=1
+else
+  GFXPAYLOAD_DYNAMIC=0
+fi
+AC_SUBST([GFXPAYLOAD_DYNAMIC])
+
 LIBS=""
 
 AC_SUBST([FONT_SOURCE])

grub-core/Makefile.core.def

@@ -964,6 +964,14 @@ module = {
   common = lib/hexdump.c;
 };
 
+module = {
+  name = hwmatch;
+  i386_pc = commands/i386/pc/hwmatch.c;
+  enable = i386_pc;
+  cflags = '$(CFLAGS_POSIX) $(CFLAGS_GNULIB)';
+  cppflags = '$(CPPFLAGS_POSIX) $(CPPFLAGS_GNULIB)';
+};
+
 module = {
   name = keystatus;
   common = commands/keystatus.c;

grub-core/commands/i386/pc/hwmatch.c

@@ -0,0 +1,146 @@
+/* hwmatch.c - Match hardware against a whitelist/blacklist.  */
+/*
+ *  GRUB  --  GRand Unified Bootloader
+ *  Copyright (C) 2011  Free Software Foundation, Inc.
+ *
+ *  GRUB is free software: you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation, either version 3 of the License, or
+ *  (at your option) any later version.
+ *
+ *  GRUB is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with GRUB.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <grub/dl.h>
+#include <grub/misc.h>
+#include <grub/command.h>
+#include <grub/pci.h>
+#include <grub/normal.h>
+#include <grub/file.h>
+#include <grub/env.h>
+#include <grub/i18n.h>
+#include <regex.h>
+
+GRUB_MOD_LICENSE ("GPLv3+");
+
+/* Context for grub_cmd_hwmatch.  */
+struct hwmatch_ctx
+{
+  grub_file_t matches_file;
+  int class_match;
+  int match;
+};
+
+/* Helper for grub_cmd_hwmatch.  */
+static int
+hwmatch_iter (grub_pci_device_t dev, grub_pci_id_t pciid, void *data)
+{
+  struct hwmatch_ctx *ctx = data;
+  grub_pci_address_t addr;
+  grub_uint32_t class, baseclass, vendor, device;
+  grub_pci_id_t subpciid;
+  grub_uint32_t subvendor, subdevice, subclass;
+  char *id, *line;
+
+  addr = grub_pci_make_address (dev, GRUB_PCI_REG_CLASS);
+  class = grub_pci_read (addr);
+  baseclass = class >> 24;
+
+  if (ctx->class_match != baseclass)
+    return 0;
+
+  vendor = pciid & 0xffff;
+  device = pciid >> 16;
+
+  addr = grub_pci_make_address (dev, GRUB_PCI_REG_SUBVENDOR);
+  subpciid = grub_pci_read (addr);
+
+  subclass = (class >> 16) & 0xff;
+  subvendor = subpciid & 0xffff;
+  subdevice = subpciid >> 16;
+
+  id = grub_xasprintf ("v%04xd%04xsv%04xsd%04xbc%02xsc%02x",
+		       vendor, device, subvendor, subdevice,
+		       baseclass, subclass);
+
+  grub_file_seek (ctx->matches_file, 0);
+  while ((line = grub_file_getline (ctx->matches_file)) != NULL)
+    {
+      char *anchored_line;
+      regex_t regex;
+      int ret;
+
+      if (! *line || *line == '#')
+	{
+	  grub_free (line);
+	  continue;
+	}
+
+      anchored_line = grub_xasprintf ("^%s$", line);
+      ret = regcomp (&regex, anchored_line, REG_EXTENDED | REG_NOSUB);
+      grub_free (anchored_line);
+      if (ret)
+	{
+	  grub_free (line);
+	  continue;
+	}
+
+      ret = regexec (&regex, id, 0, NULL, 0);
+      regfree (&regex);
+      grub_free (line);
+      if (! ret)
+	{
+	  ctx->match = 1;
+	  return 1;
+	}
+    }
+
+  return 0;
+}
+
+static grub_err_t
+grub_cmd_hwmatch (grub_command_t cmd __attribute__ ((unused)),
+		  int argc, char **args)
+{
+  struct hwmatch_ctx ctx = { .match = 0 };
+  char *match_str;
+
+  if (argc < 2)
+    return grub_error (GRUB_ERR_BAD_ARGUMENT, "list file and class required");
+
+  ctx.matches_file = grub_file_open (args[0], GRUB_FILE_TYPE_HWMATCH);
+  if (! ctx.matches_file)
+    return grub_errno;
+
+  ctx.class_match = grub_strtol (args[1], 0, 10);
+
+  grub_pci_iterate (hwmatch_iter, &ctx);
+
+  match_str = grub_xasprintf ("%d", ctx.match);
+  grub_env_set ("match", match_str);
+  grub_free (match_str);
+
+  grub_file_close (ctx.matches_file);
+
+  return GRUB_ERR_NONE;
+}
+
+static grub_command_t cmd;
+
+GRUB_MOD_INIT(hwmatch)
+{
+  cmd = grub_register_command ("hwmatch", grub_cmd_hwmatch,
+			       N_("MATCHES-FILE CLASS"),
+			       N_("Match PCI devices."));
+}
+
+GRUB_MOD_FINI(hwmatch)
+{
+  grub_unregister_command (cmd);
+}

include/grub/file.h

@@ -122,6 +122,7 @@ enum grub_file_type
     GRUB_FILE_TYPE_FS_SEARCH,
     GRUB_FILE_TYPE_AUDIO,
     GRUB_FILE_TYPE_VBE_DUMP,
+    GRUB_FILE_TYPE_HWMATCH,
 
     GRUB_FILE_TYPE_LOADENV,
     GRUB_FILE_TYPE_SAVEENV,

util/grub.d/10_linux.in

@@ -23,6 +23,7 @@ datarootdir="@datarootdir@"
 ubuntu_recovery="@UBUNTU_RECOVERY@"
 quiet_boot="@QUIET_BOOT@"
 quick_boot="@QUICK_BOOT@"
+gfxpayload_dynamic="@GFXPAYLOAD_DYNAMIC@"
 
 . "$pkgdatadir/grub-mkconfig_lib"
 
@@ -145,9 +146,10 @@ linux_entry ()
       if [ "x$GRUB_GFXPAYLOAD_LINUX" != xtext ]; then
 	  echo "	load_video" | sed "s/^/$submenu_indentation/"
       fi
-      if [ "$ubuntu_recovery" = 0 ] || [ x$type != xrecovery ]; then
-	  echo "	set gfxpayload=$GRUB_GFXPAYLOAD_LINUX" | sed "s/^/$submenu_indentation/"
   fi
+  if ([ "$ubuntu_recovery" = 0 ] || [ x$type != xrecovery ]) && \
+     ([ "x$GRUB_GFXPAYLOAD_LINUX" != x ] || [ "$gfxpayload_dynamic" = 1 ]); then
+      echo "	set gfxpayload=\$linux_gfx_mode" | sed "s/^/$submenu_indentation/"
   fi
 
   echo "	insmod gzio" | sed "s/^/$submenu_indentation/"
@@ -226,6 +228,35 @@ prepare_root_cache=
 boot_device_id=
 title_correction_code=
 
+# Use ELILO's generic "efifb" when it's known to be available.
+# FIXME: We need an interface to select vesafb in case efifb can't be used.
+if [ "x$GRUB_GFXPAYLOAD_LINUX" != x ] || [ "$gfxpayload_dynamic" = 0 ]; then
+  echo "set linux_gfx_mode=$GRUB_GFXPAYLOAD_LINUX"
+else
+  cat << EOF
+if [ "\${recordfail}" != 1 ]; then
+  if [ -e \${prefix}/gfxblacklist.txt ]; then
+    if hwmatch \${prefix}/gfxblacklist.txt 3; then
+      if [ \${match} = 0 ]; then
+        set linux_gfx_mode=keep
+      else
+        set linux_gfx_mode=text
+      fi
+    else
+      set linux_gfx_mode=text
+    fi
+  else
+    set linux_gfx_mode=keep
+  fi
+else
+  set linux_gfx_mode=text
+fi
+EOF
+fi
+cat << EOF
+export linux_gfx_mode
+EOF
+
 # Extra indentation to add to menu entries in a submenu. We're not in a submenu
 # yet, so it's empty. In a submenu it will be equal to '\t' (one tab).
 submenu_indentation=""