Compatibility Report

• Name of the game with compatibility issues: Mafia: The Old Country
• Steam AppID of the game: 1941540

System Information

• GPU: AMD Radeon RX 6800 XT
• Video driver version: [USER TO FILL - e.g., Mesa 24.1.1 or AMDVLK 2024.Q2.1]
• Kernel version: 6.8.0-71-generic
• Link to full system information report as Gist https://gist.github.com/OrigamiPaperCrane/d88a35db08f75a1c873d96c1fc4191e9
• Proton version: Proton 9.0-4 or Proton Experimental

I confirm:

• [x] that I haven't found an existing compatibility report for this game.
• [x] that I have checked whether there are updates for my system available.

-- no logs were recorded using logging launch options

Symptoms

The game causes a complete system freeze and crash when running on Linux. This is caused by the game attempting to execute privileged CPU instructions
(SMSW, SGDT) which are intercepted by the kernel's User Mode Instruction Prevention (UMIP) feature. The emulation of these instructions is extremely
resource-intensive, leading to a CPU spike of over 80% and subsequent system crash. This is a software issue within the game itself.

The kernel log (dmesg) shows the following errors repeatedly before the crash:

1 umip: MafiaTheOldCoun[9440] ip:15caf8ef0 sp:c9fe10: SMSW instruction cannot be used by applications.
2 umip: MafiaTheOldCoun[9440] ip:15caf8ef0 sp:c9fe10: For now, expensive software emulation returns the result.
3 umip: MafiaTheOldCoun[9440] ip:155594c35 sp:c986e8: SGDT instruction cannot be used by applications.
4 umip: MafiaTheOldCoun[9440] ip:155594c35 sp:c986e8: For now, expensive software emulation returns the result.

Reproduction

1. Launch "Mafia: The Old Country" on a Linux system with a UMIP-enabled kernel (standard in modern kernels) using Steam/Proton.
2. Play the game for a short period of time.
3. The system will reliably freeze and crash, requiring a hard reboot.

iostat_crash.log
dmesg_crash.log