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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!

- Bugfixes for CPU emulation correctness (critical bugfix for x86-64 emulation).

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

Candy wrote:

- Bugfixes for CPU emulation correctness (critical bugfix for x86-64 emulation).

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