Re: Bug: 2.6.11.8 msdos.c

[Bill Davidsen <davidsen@tmr.com>]

James Dingwall wrote:
>>* James Dingwall (james.dingwall@cramer.com) wrote:
>>
>>>Using vanilla 2.6.11.8 I get a "Cannot open initial 
>>
>>console" on boot,
>>
>>>2.6.11.7 was fine.  I have removed the patches to 
>>
>>fs/partitions/msdos.c and
>>
>>>this has fixed my problem.  I've read the discussion on 
>>
>>this patch but it
>>
>>>doesn't indicate that this problem may occur so there is no 
>>
>>suggested
>>
>>>solution.  I have attached my .config and my partition 
>>
>>layout is below, I
>>
>>>can provide any other information that might be useful.  
>>
>>I'm not on the list
>>
>>>so plase Cc, I will follow the thread in the archives too.
>>
>>Thanks for the report James.  To be clear, you simply backed out the
>>following: (I ask partly because this got merged in as part of the i2c
>>sysfs ChangeSet, odd)
>>
>>===== fs/partitions/msdos.c 1.26 vs 1.27 =====
>>--- 1.26/fs/partitions/msdos.c	2004-11-09 12:43:17 -08:00
>>+++ 1.27/fs/partitions/msdos.c	2005-03-07 20:41:42 -08:00
>>@@ -114,6 +114,9 @@ parse_extended(struct parsed_partitions 
>> 		 */
>> 		for (i=0; i<4; i++, p++) {
>> 			u32 offs, size, next;
>>+
>>+			if (SYS_IND(p) == 0)
>>+				continue;
>> 			if (!NR_SECTS(p) || is_extended_partition(p))
>> 				continue;
>> 
>>@@ -430,6 +433,8 @@ int msdos_partition(struct parsed_partit
>> 	for (slot = 1 ; slot <= 4 ; slot++, p++) {
>> 		u32 start = START_SECT(p)*sector_size;
>> 		u32 size = NR_SECTS(p)*sector_size;
>>+		if (SYS_IND(p) == 0)
>>+			continue;
>> 		if (!size)
>> 			continue;
>> 		if (is_extended_partition(p)) {
> 
> 
> Yes, this is the patch that I backed out.
> 
> 
>>>Disk /dev/hda: 30.0 GB, 30020272128 bytes
>>>255 heads, 63 sectors/track, 3649 cylinders
>>>Units = cylinders of 16065 * 512 = 8225280 bytes
>>>
>>>   Device Boot      Start         End      Blocks   Id  System
>>>/dev/hda1   *           1        1797    14434371   83  Linux
>>>/dev/hda2            1798        3649    14876190    5  Extended
>>>/dev/hda5            1798        1860      506016    0  Empty
>>>/dev/hda6            1861        1892      257008+  83  Linux
>>>/dev/hda7            1893        1924      257008+  83  Linux
>>>/dev/hda8            1925        2049     1004031   82  
>>
>>Linux swap / Solaris
>>
>>>/dev/hda9            2050        2112      506016    0  Empty
>>>/dev/hda10           2113        2611     4008186   83  Linux
>>>/dev/hda11           2612        2861     2008093+  83  Linux
> 
> 
> Andries' hint about changing the partition types to !0 is a fix for the
> problem.

What is the reason for the patch in the first place? Obviously it's 
intended to do something, or not do something bad, but what's wrong with 
a reserved partition?

I looked at the rest of msdos.c and it wasn't blindingly clear what the 
original intent was. A partition type of zero is unusual, but it's not 
illegal, is it? (as in violates some standard)

-- 
    -bill davidsen (davidsen@tmr.com)
"The secret to procrastination is to put things off until the
  last possible moment - but no longer"  -me