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Hi all!

The intermediate (bugfix+) release Bochs 2.6.8 has been released on May 3rd, 2015. Most of the files are now available for download, the online documentation is up-to-date and the website update will be updated soon.

Brief summary of changes:

- Bugfixes for CPU emulation correctness (critical bugfix for x86-64 emulation).
- Memory type calculation support for Bochs debugger and instrumentation.
- Added Pentium (P54C) and Broadwell ULT CPU models.
- Full save/restore support for enhanced gui debugger settings.
- Added Oracle(tm) VM VirtualBox image support (VDI version 1.1).
- SB16: Ported OPL3 emulation from DOSBox.
- Major rewrite of the lowlevel sound code (mixer thread, more detailed configuration, WAV file output).
- Bugfixes in the floppy, lowlevel cdrom, rombios, slirp and win32 gui code.

For memory type information in Bochs debugger configure with --enable-memtype and watch memory type values in the memory trace output.
Any suggestions about future extensions and bugfixes are welcome!

Stanislav

Wow, I didn't know about memory tracing before. This is a great feature for debugging. Thanks for all the improvements!

What bug was it? Critical sounds like many people here will hit it.

The bug was introduced in 2.6.7 and it resulted that any 64-bit RMW instruction with FS and GS base had its segment base added twice.
For example:

INC FS:[RAX] accessed FS_BASE+FS_BASE+RAX instead of FS_BASE+RAX

It was probably not noticed too early because not so many people using read-modify-write instructions with FS or GS base in 64-bit mode.

Stanislav