Issue #617 has been updated by gaspar ilom.

Maximilian Brune wrote in #note-1:
> Does this patch detect your issue? 
> https://review.coreboot.org/c/coreboot/+/73470

Unfortunately no, it seems that this does not cause an error, as ifdtool does 
not find the regions in FMAP. Why is that?

https://app.circleci.com/pipelines/github/gaspar-ilom/heads/37/workflows/a2223530-f5e9-4f28-be72-38f2f3e72e84/jobs/2705

```
Nov 15 18:25:27 printf "    IFDTOOL    validate IFD against FMAP\n"
Nov 15 18:25:27     IFDTOOL    validate IFD against FMAP
Nov 15 18:25:27 EOL_w541-maximized/util/ifdtool/ifdtool \
Nov 15 18:25:27          \
Nov 15 18:25:27         -t EOL_w541-maximized/coreboot.pre
Nov 15 18:25:27 Warning: No platform specified. Output may be incomplete
Nov 15 18:25:27 Warning: Not a single IFD region found in FMAP
Nov 15 18:25:27 File EOL_w541-maximized/coreboot.pre is 12582912 bytes
```

----------------------------------------
Bug #617: Missing safeguard: CBFS_SIZE greater than BIOS region in the IFD
https://ticket.coreboot.org/issues/617#change-2180

* Author: gaspar ilom
* Status: New
* Priority: Normal
* Target version: none
* Start date: 2025-11-14
* Affected versions: main
* Affected hardware: haswell
----------------------------------------
There are no effective safeguards to enforce that the `CONFIG_CBFS_SIZE` does 
not exceed the bios region as declared in the IFD.

### Impact

- Downstream under Heads with a maximized bios region for the Haswell boards 
(T440p and W541) we could verify that this bug leads to an overflow when 
training the memory cache that makes it not work. This happens both with MRC 
blob and NRI and causes very slow boot times (20s) and S3 suspend/resume does 
not work.
- Effects on other boards have not been observed but are possible.

### Expected behavior

Coreboot should not build successfully if the `CBFS_SIZE` exceeds the bios 
region in the IFD and error out reporting the problem that caused this.

## Analysis

Full details are under the PR in Heads and in particular this comment by 
@tlaurion https://github.com/linuxboot/heads/pull/2025/#issuecomment-3524672338

Ifttool reports a bios region of 0xBDEFFF (BDEFFF).
However, the coreboot config contained: 

```
CONFIG_CBFS_SIZE=0xBE4FFF
```


```
./build/x86/coreboot-25.09/util/ifdtool/ifdtool --platform ifd2 --layout 
w541_layout blobs/w541/ifd.bin && cat w541_layout 
File blobs/w541/ifd.bin is 4096 bytes
Wrote layout to w541_layout
00000000:00000fff fd
00021000:00bfffff bios
00003000:00020fff me
00001000:00002fff gbe
```

After fixing the `CONFIG_CBFS_SIZE` the issues were fixed and fast boot with 
trained memory cache and S3 suspen/resume work again with NRI: 
https://github.com/linuxboot/heads/pull/2025/commits/9b8b9cacdcea4f67c95dcec10b3153fc8c016940



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