mke2fs: do not zero out first kilobyte. Closes 3247

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
diff --git a/util-linux/mkfs_ext2.c b/util-linux/mkfs_ext2.c
index f6ccc9c..6cbbe0e 100644
--- a/util-linux/mkfs_ext2.c
+++ b/util-linux/mkfs_ext2.c
@@ -615,7 +615,11 @@
 
 	// zero boot sectors
 	memset(buf, 0, blocksize);
-	PUT(0, buf, 1024); // N.B. 1024 <= blocksize, so buf[0..1023] contains zeros
+	// Disabled: standard mke2fs doesn't do this, and
+	// on SPARC this destroys Sun disklabel.
+	// Users who need/want zeroing can easily do it with dd.
+	//PUT(0, buf, 1024); // N.B. 1024 <= blocksize, so buf[0..1023] contains zeros
+
 	// zero inode tables
 	for (i = 0; i < ngroups; ++i)
 		for (n = 0; n < inode_table_blocks; ++n)