# DF-2087 — acpi_mapbase list mutated without lock

## Verdict
REPRODUCED (source-only confirmation). Bug confirmed by source tracing.

## Mechanism
Module-global singly-linked list acpi_mapbase (OsdMemory.c:59) is read and mutated by AcpiOsMapMemory (104-116) and AcpiOsUnmapMemory (133-187) with NO lock. Concurrent map/unmap corrupts the list -> UAF or list corruption.

## Fix
Add a static struct lock acpi_map_lock (initialized via SYSINIT) and wrap all list operations with lockmgr.

## Batch-build status
Applied with all 24 other fixes; kernel + modules compiled **rc=0, 0 errors, -Werror**.