This fix, at least in its current form, has a potential to break grub for
users having more than one drive, unless they are careful enough to check and
fix their device.map after upgrade.
Old mkdevicemaps assigned grub device numbers in the sort order of kernel
device names, which was right more often than not. On the other hand, the sort
order of (pretty much random) stable names, used by new version, is extremely
unlikely to have any correlation to grub device order.
Included is a rough patch which preserves the kernel-name order for grub
devices when generating device.map.
--
Vadim Solomin
--- grub2-1.98+20100706/util/deviceiter.c 2010-07-06 20:57:30.000000000 +0400
+++ grub2-1.98+20100706-new/util/deviceiter.c 2010-07-09 07:33:16.135823063 +0400
@@ -467,14 +467,21 @@
}
#ifdef __linux__
+struct device
+{
+ char *stable;
+ char *kernel;
+};
+
/* Like strcmp, but doesn't require a cast for use as a qsort comparator. */
static int
compare_file_names (const void *a, const void *b)
{
- const char *left = *(const char **) a;
- const char *right = *(const char **) b;
+ const char *left = ((const struct device *) a) -> kernel;
+ const char *right = ((const struct device *) b) -> kernel;
return strcmp (left, right);
}
+
#endif /* __linux__ */
void
@@ -507,10 +514,11 @@
if (dir)
{
struct dirent *entry;
- char **names;
- size_t names_len = 0, names_max = 1024, i;
+ struct device *devs;
+ size_t devs_len = 0, devs_max = 1024, i;
+ char *path = 0;
- names = xmalloc (names_max * sizeof (*names));
+ devs = xmalloc (devs_max * sizeof (*devs));
/* Dump all the directory entries into names, resizing if
necessary. */
@@ -526,35 +534,39 @@
/* Skip RAID entries; they are handled by upper layers. */
if (strncmp (entry->d_name, "md-", sizeof ("md-") - 1) == 0)
continue;
- if (names_len >= names_max)
+ if (devs_len >= devs_max)
{
- names_max *= 2;
- names = xrealloc (names, names_max * sizeof (*names));
+ devs_max *= 2;
+ devs = xrealloc (devs, devs_max * sizeof (*devs));
}
- names[names_len++] = xasprintf (entry->d_name);
+ devs[devs_len].stable = xasprintf (entry->d_name);
+ path = xasprintf("/dev/disk/by-id/%s", entry->d_name);
+ devs[devs_len++].kernel = canonicalize_file_name(path);
+ free(path);
}
/* /dev/disk/by-id/ usually has a few alternative identifications of
devices (e.g. ATA vs. SATA). check_device_readable_unique will
ensure that we only get one for any given disk, but sort the list
so that the choice of which one we get is stable. */
- qsort (names, names_len, sizeof (*names), &compare_file_names);
+ qsort (devs, devs_len, sizeof (*devs), &compare_file_names);
closedir (dir);
/* Now add all the devices in sorted order. */
- for (i = 0; i < names_len; ++i)
+ for (i = 0; i < devs_len; ++i)
{
- char *path = xasprintf ("/dev/disk/by-id/%s", names[i]);
+ char *path = xasprintf ("/dev/disk/by-id/%s", devs[i].stable);
if (check_device_readable_unique (path))
{
if (hook (path, 0))
goto out;
}
free (path);
- free (names[i]);
+ free (devs[i].stable);
+ free (devs[i].kernel);
}
- free (names);
+ free (devs);
}
}
