ACPI: RSDP - ERROR: Invalid checksum

ACPI: RSDP - ERROR: Invalid checksum

[Klaus Muth]

Hi!
I've got here a brand new IBM xServer 236 and try to install debian sarge with 
kernel 2.6 and I'm now at the end of my knowledge. *sigh*. 

When I had a test machine, all went fine, both SMT Processors were detected 
and the system was stable with 4 Processors. Now, that I have the production 
machine (newer BIOS), the thing drives me crazy...

Kernel 2.6.11-mm4 dmesg:

Linux version 2.6.11-mm4-ibm1 (root@alderaan) (gcc-Version 3.3.5 (Debian 
1:3.3.5-12)) #1 SMP PREEMPT Fri Jun 3 10:29:57 CEST 2005
BIOS-provided physical RAM map:
 BIOS-e820: 0000000000000000 - 000000000009c000 (usable)
 BIOS-e820: 000000000009c000 - 00000000000a0000 (reserved)
 BIOS-e820: 00000000000e0000 - 0000000000100000 (reserved)
 BIOS-e820: 0000000000100000 - 00000000bffcae80 (usable)
 BIOS-e820: 00000000bffcae80 - 00000000bffcf800 (ACPI data)
 BIOS-e820: 00000000bffcf800 - 00000000c0000000 (reserved)
 BIOS-e820: 00000000fec00000 - 0000000100000000 (reserved)
2175MB HIGHMEM available.
896MB LOWMEM available.
found SMP MP-table at 0009c140
On node 0 totalpages: 786378
  DMA zone: 4096 pages, LIFO batch:1
  Normal zone: 225280 pages, LIFO batch:16
  HighMem zone: 557002 pages, LIFO batch:16
DMI 2.3 present.
ACPI: RSDP (v002 IBM                                   ) @ 0x000fdfb0
  >>> ERROR: Invalid checksum
Intel MultiProcessor Specification v1.4
    Virtual Wire compatibility mode.
OEM ID: IBM ENSW Product ID: REDWOOD SMP  APIC at: 0xFEE00000
Processor #0 15:4 APIC version 20
....

2.6.11 kernel with Zhenyu Z Wang's brute force searching for sane rsdp patch:

Linux version 2.6.11-ibm6 (root@alderaan) (gcc-Version 3.3.5 (Debian 
1:3.3.5-12)
) #1 SMP Tue Jun 7 15:08:26 CEST 2005
BIOS-provided physical RAM map:
 BIOS-e820: 0000000000000000 - 000000000009c000 (usable)
 BIOS-e820: 000000000009c000 - 00000000000a0000 (reserved)
 BIOS-e820: 00000000000e0000 - 0000000000100000 (reserved)
 BIOS-e820: 0000000000100000 - 00000000bffcae80 (usable)
 BIOS-e820: 00000000bffcae80 - 00000000bffcf800 (ACPI data)
 BIOS-e820: 00000000bffcf800 - 00000000c0000000 (reserved)
 BIOS-e820: 00000000fec00000 - 0000000100000000 (reserved)
2175MB HIGHMEM available.
896MB LOWMEM available.
found SMP MP-table at 0009c140
On node 0 totalpages: 786378
  DMA zone: 4096 pages, LIFO batch:1
  Normal zone: 225280 pages, LIFO batch:16
  HighMem zone: 557002 pages, LIFO batch:16
DMI 2.3 present.
Wrong RSDP!! 0xbffcf780
ACPI: Unable to locate RSDP
Intel MultiProcessor Specification v1.4
    Virtual Wire compatibility mode.
... yadda, yadda...

The RSDP found by acpidmp:
RSDP "IBM" @ 0x000fdfb0
  0000: 52 53 44 20 50 54 52 20 75 49 42 4d 20 20 20 02  RSD PTR uIBM   .
  0010: 80 f7 fc bf                                      ....

Problems: No SMT, PCI devices complaining in dmesg about invalid IRQ, probably 
buggy MP table, sometimes losing timer ticks on boot and kernel panic.

I also tried to correct the DSDT (sorry, I didn't know better), but the iasl 
did not find any errors, so what...

The intresting fact is, that the Redhat Enterprise Linux 3 Kernel (2.4.21 with 
380 patches/1,6x10^6 lines of patch) has no problems with the RSDP. I could 
not identify the patch, which made the RSDP work....

Please help me! Make my 236 work with a minimum of patches...
-- 
Klaus Muth
HAGOS eG                      Industriestr. 62      fon: (+49) 711 78805-86
EDV-Programmierung            70565  Stuttgart      fax: (+49) 711 78805-35
http://www.hagos.de               Germany              mailto:muth-5lHx5lHeYlQ@public.gmane.org


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Re: ACPI: RSDP - ERROR: Invalid checksum

[Klaus Muth]

Hi!

Ok, I do the Ingrid.

Am Dienstag, 7. Juni 2005 15:46 schrieb Klaus Muth:
> ACPI: RSDP (v002 IBM                                   ) @ 0x000fdfb0
>
>   >>> ERROR: Invalid checksum
[...]
> The RSDP found by acpidmp:
> RSDP "IBM" @ 0x000fdfb0
>   0000: 52 53 44 20 50 54 52 20 75 49 42 4d 20 20 20 02  RSD PTR uIBM   .
>   0010: 80 f7 fc bf                                      ....

Yeah, this is the problem. I downgraded the BIOS, now the kernel uses ACPI:

ACPI: RSDP (v000 IBM                                   ) @ 0x000fdfc0
ACPI: RSDT (v001 IBM    SERONYXP 0x00001000 IBM  0x45444f43) @ 0xbffcf780
ACPI: FADT (v001 IBM    SERONYXP 0x00001000 IBM  0x45444f43) @ 0xbffcf700
ACPI: MADT (v001 IBM    SERONYXP 0x00001000 IBM  0x45444f43) @ 0xbffcf640
ACPI: MCFG (v001 IBM    SERONYXP 0x00001000 IBM  0x45444f43) @ 0xbffcf600
ACPI: DSDT (v001 IBM    SERGEODE 0x00001000 MSFT 0x0100000b) @ 0x00000000
ACPI: PM-Timer IO Port: 0x588
ACPI: Local APIC address 0xfee00000
ACPI: LAPIC (acpi_id[0x00] lapic_id[0x00] enabled)
[and so on]

and acpidmp:

RSDP "IBM" @ 0x000fdfc0
  0000: 52 53 44 20 50 54 52 20 77 49 42 4d 20 20 20 00  RSD PTR wIBM   .
  0010: 80 f7 fc bf 

Is it possible, that IBM did update the version without updating the checksum?
Now, that I downgraded the BIOS, the x236 runs like a charm with 4 processors 
and all PCI interrupts routed correctly ;). I strongly suspect now, that the 
linux acpi code is correct with saying "Checksum error" ;).
-- 
Klaus Muth
HAGOS eG                      Industriestr. 62      fon: (+49) 711 78805-86
EDV-Programmierung            70565  Stuttgart      fax: (+49) 711 78805-35
http://www.hagos.de               Germany              mailto:muth-5lHx5lHeYlQ@public.gmane.org


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Re: ACPI: RSDP - ERROR: Invalid checksum

[Klaus Muth]

Am Mittwoch, 8. Juni 2005 15:29 schrieb Klaus Muth:
> Hi!
>
> Ok, I do the Ingrid.
AAARGH. Another Ingrid. Seems, that the acpi_find_rsdp() is rather optimistic 
about finding the RSDP [arch/i386/kernel/acpi/boot.c, acpi_scan_rsdp]:
 /*
  * Scan all 16-byte boundaries of the physical memory region for the
  * RSDP signature.
  */
 for (offset = 0; offset < length; offset += 16) {
  if (strncmp((char *) (start + offset), "RSD PTR ", sig_len))
   continue;
  return (start + offset);
 }

It seems to happen, that the IBM BIOS contains just the string "RSD PTR " 
exactly at a 16-Byte-Boundary before the real RSDP block, so the wrnog 
address is returned and acpi_table_init() in drivers/acpi/tables.c fails to 
checksum this block of course.

The patched up RedHat Kernel uses 
static struct acpi_table_rsdp * __init
acpi_find_root_pointer(void)
{
 struct acpi_table_rsdp * rsdp;

 /*
  * Physical address is given
  */
 /*
  * Region 1) Search EBDA (low memory) paragraphs
  */
 rsdp = acpi_tb_scan_memory_for_rsdp(__va(LO_RSDP_WINDOW_BASE),
      LO_RSDP_WINDOW_SIZE);

 if (rsdp)
  return rsdp;

 /*
  * Region 2) Search upper memory: 16-byte boundaries in E0000h-F0000h
  */
 rsdp = acpi_tb_scan_memory_for_rsdp(__va(HI_RSDP_WINDOW_BASE),
            HI_RSDP_WINDOW_SIZE);

 
          
 if (rsdp)
  return rsdp;

 printk(KERN_ERR "ACPI: System description tables not found\n");
 return NULL;
}

to find the RSDP and seems to find it in Region 2. GRRRR.

Is there any patch to do the same with a vanilla 2.6 Kernel?
-- 
Klaus Muth
HAGOS eG                      Industriestr. 62      fon: (+49) 711 78805-86
EDV-Programmierung            70565  Stuttgart      fax: (+49) 711 78805-35
http://www.hagos.de               Germany              mailto:muth-5lHx5lHeYlQ@public.gmane.org


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This SF.Net email is sponsored by: NEC IT Guy Games.  How far can you shotput
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Re: ACPI: RSDP - ERROR: Invalid checksum

[Klaus Muth]

Am Donnerstag, 9. Juni 2005 11:13 schrieb Klaus Muth:

> It seems to happen, that the IBM BIOS contains just the string "RSD PTR "
> exactly at a 16-Byte-Boundary before the real RSDP block, so the wrnog
> address is returned and acpi_table_init() in drivers/acpi/tables.c fails to
> checksum this block of course.
[... 2.4 kernel finding the real RSDP ...]
> Is there any patch to do the same with a vanilla 2.6 Kernel?

Ahem. Did I hit a FAQ? If so: I could not find the answer. Could just someone 
be so kind to point me in the right direction?

TIA
-- 
Klaus Muth
HAGOS eG                      Industriestr. 62      fon: (+49) 711 78805-86
EDV-Programmierung            70565  Stuttgart      fax: (+49) 711 78805-35
http://www.hagos.de               Germany              mailto:muth-5lHx5lHeYlQ@public.gmane.org


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RE: ACPI: RSDP - ERROR: Invalid checksum

[Moore, Robert]

Does this work under windows?
Please post a memory dump of the area in question, I would be very
interested to see it.
Bob


> -----Original Message-----
> From: acpi-devel-admin-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org [mailto:acpi-devel-
> admin-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org] On Behalf Of Klaus Muth
> Sent: Tuesday, June 28, 2005 12:25 AM
> To: acpi-devel-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org
> Subject: Re: [ACPI] ACPI: RSDP - ERROR: Invalid checksum
> 
> Am Donnerstag, 9. Juni 2005 11:13 schrieb Klaus Muth:
> 
> > It seems to happen, that the IBM BIOS contains just the string "RSD
PTR
> "
> > exactly at a 16-Byte-Boundary before the real RSDP block, so the
wrnog
> > address is returned and acpi_table_init() in drivers/acpi/tables.c
fails
> to
> > checksum this block of course.
> [... 2.4 kernel finding the real RSDP ...]
> > Is there any patch to do the same with a vanilla 2.6 Kernel?
> 
> Ahem. Did I hit a FAQ? If so: I could not find the answer. Could just
> someone
> be so kind to point me in the right direction?
> 
> TIA
> --
> Klaus Muth
> HAGOS eG                      Industriestr. 62      fon: (+49) 711
78805-
> 86
> EDV-Programmierung            70565  Stuttgart      fax: (+49) 711
78805-
> 35
> http://www.hagos.de               Germany
> mailto:muth-5lHx5lHeYlQ@public.gmane.org
> 
> 
> -------------------------------------------------------
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> _______________________________________________
> Acpi-devel mailing list
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Re: ACPI: RSDP - ERROR: Invalid checksum

[Klaus Muth]

Am Dienstag, 28. Juni 2005 17:19 schrieb Moore, Robert:
> Does this work under windows?
I plainly don't know. This is a server and I won't install windows on it (I 
don't even have any windows license).

> Please post a memory dump of the area in question, I would be very
> interested to see it.

Hups. How do I retreive that? I've got no idea :(.

klaus
-- 
Klaus Muth
HAGOS eG                      Industriestr. 62      fon: (+49) 711 78805-86
EDV-Programmierung            70565  Stuttgart      fax: (+49) 711 78805-35
http://www.hagos.de               Germany              mailto:muth-5lHx5lHeYlQ@public.gmane.org


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Re: ACPI: RSDP - ERROR: Invalid checksum

[Klaus Muth]

Am Mittwoch, 29. Juni 2005 09:30 schrieb Klaus Muth:

> Hups. How do I retreive that? I've got no idea :(.
Argh! Little bit of googling helps around "no idea"s...

For every one else facing my problem: 
  dd if=/dev/mem of=~/mem bs=1k count=1k
  xxd mem > dump
The dd part has to be as root, the xxd (or every other hexdump program) part 
should be as unprivileged user.  

[...IBM 1.04 BIOS...]
009c340: 0000 0000 0000 0000 0000 0000 0000 0000  ................
009c350: 0000 0000 0000 0000 0000 0000 0000 0000  ................
009c360: 0000 0000 0000 0000 0000 0000 0000 0000  ................
009c370: 0000 0000 0000 0000 0000 0000 0000 0000  ................
009c380: 0000 0000 0000 0000 0000 0000 0000 0000  ................
009c390: 0000 0000 0000 0000 0000 0000 0000 0000  ................
009c3a0: 0000 0000 0000 0000 0300 0000 0005 0000  ................
009c3b0: 2200 26c3 0000 0000 0000 0000 0000 0000  ".&.............
009c3c0: 0000 0010 0010 0000 0000 0000 0000 0010  ................
009c3d0: 0010 0000 0000 0000 0000 0000 0000 0000  ................
009c3e0: 0000 0000 0400 0400 0000 0000 0000 0000  ................
009c3f0: 0400 0400 0000 0000 0000 0000 0000 0000  ................
009c400: 0000 0000 0000 0000 0000 0000 0000 0000  ................
009c410: 0000 0000 0000 0000 0000 0000 0000 0000  ................
009c420: 0000 0014 1400 0000 0014 1400 0000 0000  ................
009c430: 0000 0041 0f41 0f00 0000 0000 0000 0041  ...A.A.........A
009c440: 0f41 0f00 0000 0000 0000 0000 0000 0000  .A..............
009c450: 0000 0080 0c80 0c00 0000 0000 0000 0080  ................
009c460: 0c80 0c00 0000 0000 0000 0000 0000 0000  ................
009c470: 0000 0000 0000 0000 0000 0000 0000 0000  ................
009c480: 0000 0000 0000 0000 0000 002f 0000 0000  .........../....
009c490: 0004 8007 0000 00c7 0000 0000 0000 0000  ................
009c4a0: 0000 0000 0000 0000 0000 0000 0000 0000  ................
009c4b0: 5253 4420 5054 5220 6f4d 2020 2049 4200  RSD PTR oM   IB.
009c4c0: 80f7 fcc7 0000 0000 0000 0000 0000 0000  ................
009c4d0: 0000 0000 0000 0000 0000 0000 0000 0000  ................
009c4e0: 0000 0000 0000 0000 0000 0000 0000 0000  ................
009c4f0: 0000 0000 0000 0000 0000 0000 0000 0000  ................
009c500: 0000 0000 0000 0000 0000 0000 0000 0000  ................
009c510: 0000 0000 0000 0000 0000 0000 0000 0000  ................
009c520: 0000 0000 0000 0000 0000 0000 0000 0000  ................
009c530: 0000 0000 0000 0000 0000 0000 0000 0000  ................
009c540: 0000 0000 0000 0000 0000 0000 0000 0000  ................
009c550: 0000 0000 0000 0000 0000 0000 0000 0000  ................
009c560: 0000 0000 0000 0000 0000 0000 0000 0000  ................
009c570: 0000 0000 0000 0000 0000 0000 0000 0000  ................
[...]
00fdf70: d486 87d5 0000 0000 0000 0000 0000 0000  ................
00fdf80: 2450 6e50 1021 0000 c000 0000 007a 7300  $PnP.!.......zs.
00fdf90: f07f 7300 000f 0000 0000 0000 f000 000f  ..s.............
00fdfa0: 0000 0000 0000 0000 0000 0000 0000 0000  ................
00fdfb0: 5253 4420 5054 5220 6d49 424d 2020 2002  RSD PTR mIBM   .
00fdfc0: 80f7 fcc7 2400 0000 0000 0000 0000 0000  ....$...........
00fdfd0: c700 0000 0000 0000 0000 0000 0000 0000  ................
00fdfe0: 5f53 4d5f 931f 0203 eb00 0000 0000 0000  _SM_............
00fdff0: 5f44 4d49 5fd0 0c09 9785 0f00 3500 2300  _DMI_.......5.#.
00fe000: ffff ffff ffff ffff 434f 5052 2e20 4942  ........COPR. IB
00fe010: 4d20 3139 3831 2c20 3139 3834 0000 0000  M 1981, 1984....
00fe020: 0000 0000 0000 0000 0000 0000 0000 0000  ................
00fe030: 0000 0000 0000 0000 0000 0000 0000 0000  ................
00fe040: 0000 0000 0000 0000 0000 0000 0000 0000  ................

acpi_scan_rsdp() finds of course the signature at 009c4b0, which is in fact no 
RSDP block, the RSDP block is at 00fdfb0. The working 1.02 BIOS is filled up 
with zeroes around 009c4b0, this is why the older BIOS is working. If you 
need more dump, just mail me.

Thank you very much ;)

klaus
-- 
Gruß, Klaus Muth
Zentrale / EDV

Fon:  0711/78805 - 86
Fax:  0711/78805 - 35


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RE: ACPI: RSDP - ERROR: Invalid checksum

[Moore, Robert]

Thanks for the memory dump.  I will look at this against the ACPI spec
and get back to you.

I think that we may need to change the memory scan code (in tbxfroot.c)
to search for the first "RSD PTR" string with an associated table that
has a valid checksum. I also think that this has been requested before.

Bob

> -----Original Message-----
> From: Klaus Muth [mailto:muth-5lHx5lHeYlQ@public.gmane.org]
> Sent: Wednesday, June 29, 2005 1:42 AM
> To: acpi-devel-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org
> Cc: Moore, Robert
> Subject: Re: [ACPI] ACPI: RSDP - ERROR: Invalid checksum
> 
> Am Mittwoch, 29. Juni 2005 09:30 schrieb Klaus Muth:
> 
> > Hups. How do I retreive that? I've got no idea :(.
> Argh! Little bit of googling helps around "no idea"s...
> 
> For every one else facing my problem:
>   dd if=/dev/mem of=~/mem bs=1k count=1k
>   xxd mem > dump


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RE: ACPI: RSDP - ERROR: Invalid checksum

[Moore, Robert]

The actual ACPI CA core will continue until it finds a valid "RSD PTR "
string with a valid table checksum, since at least 11/2004:

19 November 2004.  Summary of changes for version 20041119:

Modified the RSDP memory scan mechanism to support the extended
checksum for ACPI 2.0 (and above) RSDPs. Note that the search
continues until a valid RSDP signature is found with a valid
checksum.



Unfortunately, I believe that Linux still has two versions of the RSDP
memory scan code, and the "other" version (not within the ACPI CA core)
continues to be down-revved and incorrect.

We really need to get rid of the "other" version so that there is only
one version of this important code.

Bob


> -----Original Message-----
> From: acpi-devel-admin-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org [mailto:acpi-devel-
> admin-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org] On Behalf Of Moore, Robert
> Sent: Tuesday, June 28, 2005 8:20 AM
> To: Klaus Muth; acpi-devel-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org
> Subject: RE: [ACPI] ACPI: RSDP - ERROR: Invalid checksum
> 
> Does this work under windows?
> Please post a memory dump of the area in question, I would be very
> interested to see it.
> Bob
> 
> 
> > -----Original Message-----
> > From: acpi-devel-admin-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org [mailto:acpi-devel-
> > admin-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org] On Behalf Of Klaus Muth
> > Sent: Tuesday, June 28, 2005 12:25 AM
> > To: acpi-devel-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org
> > Subject: Re: [ACPI] ACPI: RSDP - ERROR: Invalid checksum
> >
> > Am Donnerstag, 9. Juni 2005 11:13 schrieb Klaus Muth:
> >
> > > It seems to happen, that the IBM BIOS contains just the string
"RSD
> PTR
> > "
> > > exactly at a 16-Byte-Boundary before the real RSDP block, so the
> wrnog
> > > address is returned and acpi_table_init() in drivers/acpi/tables.c
> fails
> > to
> > > checksum this block of course.
> > [... 2.4 kernel finding the real RSDP ...]
> > > Is there any patch to do the same with a vanilla 2.6 Kernel?
> >
> > Ahem. Did I hit a FAQ? If so: I could not find the answer. Could
just
> > someone
> > be so kind to point me in the right direction?
> >
> > TIA
> > --
> > Klaus Muth
> > HAGOS eG                      Industriestr. 62      fon: (+49) 711
> 78805-
> > 86
> > EDV-Programmierung            70565  Stuttgart      fax: (+49) 711
> 78805-
> > 35
> > http://www.hagos.de               Germany
> > mailto:muth-5lHx5lHeYlQ@public.gmane.org
> >
> >
> > -------------------------------------------------------
> > SF.Net email is sponsored by: Discover Easy Linux Migration
Strategies
> > from IBM. Find simple to follow Roadmaps, straightforward articles,
> > informative Webcasts and more! Get everything you need to get up to
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> > _______________________________________________
> > Acpi-devel mailing list
> > Acpi-devel-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org
> > https://lists.sourceforge.net/lists/listinfo/acpi-devel
> 
> 
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RE: ACPI: RSDP - ERROR: Invalid checksum

[Perry Hutchison]

> The actual ACPI CA core will continue until it finds a valid
> "RSD PTR " string with a valid table checksum, since at least
> 11/2004:
>
> + 19 November 2004.  Summary of changes for version 20041119:
>
> + Modified the RSDP memory scan mechanism to support the extended
> + checksum for ACPI 2.0 (and above) RSDPs. Note that the search
> + continues until a valid RSDP signature is found with a valid
> + checksum.
>
> Unfortunately, I believe that Linux still has two versions of
> the RSDP memory scan code, and the "other" version (not within
> the ACPI CA core) continues to be down-revved and incorrect.

At least as recently as 20050513, acpica-unix included common/a16find.c,
which contains (in AfFindRsdp()):

  /* Scan low memory */
  do
  {
    if (strncmp (Rove.ptr, RSDP_SIG, (size_t) 8) == 0)
    {
      /* TBD: Checksum check is invalid for X descriptor */
/*    if (AcpiTbChecksum (Rove.ptr, sizeof(RSDP_DESCRIPTOR)) != 0)
      {
 */
      AcpiOsPrintf ("RSDP found at %p (Lo block)\n", Rove.ptr);

IOW the checksum check is bypassed (and it is omitted entirely --
not even "present but commented out" -- in the second search loop).
If one of the Linux versions is derived from this file, and if
someone is keeping track of heritage, maybe an update to a16find.c
would be noticed as needing to be merged into the derived code.


BTW, while tracking this down -- I remembered the code, but not
its location -- I happened across a comment which could likely
use an update.  tables/tbinstal.c has

* 4) Table checksum must be valid (with the exception of the FACS
*    which has no checksum for some odd reason)

while tbutils.c has the more informative

* 4) Table checksum must be valid (with the exception of the FACS
*     which has no checksum because it contains variable fields)


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