Memmove causing program crashes, giving SIGTRAP in GDB(?)

[Eliot Moss]

On 2/26/2026 9:04 PM, KENNON J CONRAD wrote:
> Perhaps something like this?  Maybe I need to try a BIOS update?

Yes, something *like* these flaws.  The thing is to find out if your specific
processor has a flaw that needs an update, etc.

> Intel Haswell (and related architectures) processors may experience stability issues, including machine check errors (MCEs), due to a microcode bug related to REP MOVS (specifically REP MOVSB or REP MOVSQ) handling. These issues often cause system crashes or lockups, leading to microcode, BIOS/UEFI updates to resolve them.
> Debian Wiki
>   +4
> Issue: A high-rate of interrupts or specific memory operations can cause REP MOVS instructions to trigger Machine Check Errors (MCE) or internal errors (IERR) on older processors.
> Affected Processors: The bug primarily impacts older Intel processors, including Haswell and Broadwell architectures.
> Fix/Mitigation: The primary solution is to apply the latest motherboard BIOS/UEFI update, which contains the corrected microcode update (often labelled 20180108 or later).
> Background: This is linked to Intel’s efforts to fix security vulnerabilities (like Spectre), where early patches for Haswell/Broadwell caused unexpected instability, requiring further refinements.
> Debian Wiki
>   +4
> 
> -Kennon

EM