From 1657812278bb086ca31dc4af24dd0e1627504869 Mon Sep 17 00:00:00 2001
From: Michal Suchanek <msuchanek@suse.de>
Date: Tue, 31 Oct 2017 14:28:54 +0100
Subject: [PATCH 052/272] grub-install: remove useless check PReP partition is
 empty.

References: bsc#1065738

The grub-install rewrite in commit cd46aa6cefab checks that the PPeP
partition does not install an ELF binary before writing grub to it. This
causes regression in installer scripts that expect to be able to
reinstall bootloaders without first witping the partition by hand.

Fixes: cd46aa6cefab ("Rewrite grub-install, grub-mkrescue,
    grub-mkstandalone and grub-mknetdir ")
---
 util/grub-install.c | 43 +++----------------------------------------
 1 file changed, 3 insertions(+), 40 deletions(-)

diff --git a/util/grub-install.c b/util/grub-install.c
index 1d2bf4dd3..036a66dc6 100644
--- a/util/grub-install.c
+++ b/util/grub-install.c
@@ -746,34 +746,6 @@ is_prep_partition (grub_device_t dev)
   return 0;
 }
 
-static int
-is_prep_empty (grub_device_t dev)
-{
-  grub_disk_addr_t dsize, addr;
-  grub_uint32_t buffer[32768];
-
-  dsize = grub_disk_native_sectors (dev->disk);
-  for (addr = 0; addr < dsize;
-       addr += sizeof (buffer) / GRUB_DISK_SECTOR_SIZE)
-    {
-      grub_size_t sz = sizeof (buffer);
-      grub_uint32_t *ptr;
-
-      if (sizeof (buffer) / GRUB_DISK_SECTOR_SIZE > dsize - addr)
-	sz = (dsize - addr) * GRUB_DISK_SECTOR_SIZE;
-      grub_disk_read (dev->disk, addr, 0, sz, buffer);
-
-      if (addr == 0 && grub_memcmp (buffer, ELFMAG, SELFMAG) == 0)
-	return 1;
-
-      for (ptr = buffer; ptr < buffer + sz / sizeof (*buffer); ptr++)
-	if (*ptr)
-	  return 0;
-    }
-
-  return 1;
-}
-
 static void
 bless (grub_device_t dev, const char *path, int x86)
 {
@@ -1942,18 +1914,9 @@ main (int argc, char *argv[])
 	    {
 	      grub_util_error ("%s", _("the chosen partition is not a PReP partition"));
 	    }
-	  if (is_prep_empty (ins_dev))
-	    {
-	      if (write_to_disk (ins_dev, imgfile))
-		grub_util_error ("%s", _("failed to copy Grub to the PReP partition"));
-	      grub_set_install_backup_ponr ();
-	    }
-	  else
-	    {
-	      char *s = xasprintf ("dd if=/dev/zero of=%s", install_device);
-	      grub_util_error (_("the PReP partition is not empty. If you are sure you want to use it, run dd to clear it: `%s'"),
-			       s);
-	    }
+	  if (write_to_disk (ins_dev, imgfile))
+	    grub_util_error ("%s", _("failed to copy Grub to the PReP partition"));
+	  grub_set_install_backup_ponr ();
 	  grub_device_close (ins_dev);
 	  if (update_nvram)
 	    grub_install_register_ieee1275 (1, grub_util_get_os_disk (install_device),
-- 
2.41.0