Windows 8 build 8112 (fbl_core1_soc)
| Build of Windows 8 | |
 | |
| OS family | Windows NT |
|---|---|
| Version number | 6.2 |
| Build number | 8112 |
| Build revision | 0 |
| Architecture | ARM32 (ARMv7) |
| Build lab | fbl_core1_soc |
| Compiled on | 2011-09-12 2011-09-16 |
| SKUs | |
| Preinstallation Environment | |
| About dialog | |
Windows 8 build 8112 (fbl_core1_soc) is a build of Windows 8. A WIM image containing the ARMv7 compile of this build's Preinstallation Environment was uploaded onto the Internet Archive on 19 September 2023.[1]
Changes[edit | edit source]
Boot environment[edit | edit source]
The EFI firmware parameters substructure of the boot library (passed to the entry point of a boot application) has been changed; attempting to load older boot applications starting from this build (or vice versa) will result in a crash due to differing element offsets.
The option to enable safe mode under an ARMv7 environment has been removed from the Windows boot loader.
Bugs and quirks[edit | edit source]
Secure Digital bus driver read/write protection[edit | edit source]
MultiMediaCard-based storage mediums (such as Secure Digital (SD) cards and eMMCs) are mounted by the operating system as read-only/write-protected file systems,[a] preventing the build from booting if deployed onto eMMC storage; the build must instead be booted from a non-MMC medium such as a RAM disk, an external USB mass storage device, or via a Hyper-V virtual hard disk (VHD) image. To mount the eMMC as a read/write filesystem, the sdbus.sys function SdhcIsWriteProtected must be patched to return 0 (and the PE checksum fixed); patch file offsets 0x138 and 0x8cc4 to 7c 07 02 and 00 20 70 47, respectively.
Private builds of core components[edit | edit source]
The available copy is specific in that the kernel (ntoskrnl.exe) and OS loaders (winload.efi, winresume.efi) were replaced with privately built variants, compiled by Microsoft employee Adam Glass on 16 September 2011 (per the TimeDateStamp values in the executables' PE headers).[b] The only discernible changes that appear to be present in the private components are against Windows kernel function KeRestoreProcessorState, which now includes a conditional check for whether bit 1 of a debug register is set prior to calling runtime library function RtlRestoreContext; other binaries pertaining to the boot environment itself now utilize instruction synchronization barriers in place of data synchronization barriers in two unnamed functions.
The original kernel and boot loaders are still present within the image's side-by-side component store. A privately built boot manager (bootarm.efi) was also included as part of the upload, albeit with a single-bit patch to point the location to load the boot configuration data to \EFI\Microsoft\Boot\BCE, rather than \EFI\Microsoft\Boot\BCD.
The privately built components bear a build tag for build 6.2.8112.0 (fbl_core1_soc(adamg).110621-0330).[b]
Compatibility[edit | edit source]
This build contains ARM Cortex-A9 timer hardware abstraction layer extensions for the NVIDIA Tegra 2/3 systems-on-a-chip and the Texas Instruments OMAP4 SoC line, as well as timer extensions for the Qualcomm Snapdragon S3 (MSM8660) processor which were later added to the image. A HAL extension for the ARM SP804 dual timer is also included.
USB 2.0 kernel debugger extensions for the Tegra, Qualcomm and OMAP4 SoCs are also available out-of-box.
Gallery[edit | edit source]
Command Prompt with Test Mode watermark
Registry Information
Notes[edit | edit source]
- ↑ Only observed on Surface RT hardware as of writing; other hardware untested.
- ↑ 2.0 2.1 Microsoft employees did not occasionally run the time build script in their personal compiles and often forward- and reverse-integrated code to/from newer build labs while retaining an older compile date.