macOS 26.2: MEMORYSTATUS_CMD_CONVERT_MEMLIMIT_MB returns EINVAL on M4 Max 128GB - Apps Crash

Anyone having this issue? I reported to apple and trying to get community support if others are having a issue.

FEEDBACK ID: *****

PLATFORM: macOS

AREA: Kernel

VERSION: macOS 26.2 (25C56)

SUMMARY:

Applications crash randomly on MacBook Pro M4 Max with 128GB RAM running macOS 26.2 Tahoe. The root cause is a kernel bug where the MEMORYSTATUS_CMD_CONVERT_MEMLIMIT_MB syscall returns EINVAL (error 22), causing runningboardd to incorrectly invalidate app assertions and terminate processes.

HARDWARE:

- MacBook Pro (Mac16,5)

- Apple M4 Max

- 128GB Unified Memory

- macOS 26.2 (Build 25C56)

THE BUG:

The kernel parameter kern.max_task_pmem is incorrectly set to 0 on 128GB systems:

$ sysctl kern.max_task_pmem kern.entitled_max_task_pmem hw.memsize

kern.max_task_pmem: 0

kern.entitled_max_task_pmem: 0

hw.memsize: *********

This causes MEMORYSTATUS_CMD_CONVERT_MEMLIMIT_MB to return EINVAL:

runningboardd: [com.apple.runningboard:jetsam] memorystatus_control error:

MEMORYSTATUS_CMD_CONVERT_MEMLIMIT_MB(-1) returned -1 22 (Invalid argument)

runningboardd: [com.apple.runningboard:jetsam] memorystatus_control error:

MEMORYSTATUS_CMD_CONVERT_MEMLIMIT_MB(0) returned -1 22 (Invalid argument)

SYMPTOMS:

- Applications suddenly quit without warning (Brave, Chrome, PhpStorm, GoLand, VS Code, Slack)

- Occurs when running 2-3 apps simultaneously

- System has 90%+ free memory when crashes occur

- No crash reports generated (apps killed by system, not crashing)

- No "Application Memory" warning displayed

STEPS TO REPRODUCE:

1. Boot MacBook Pro M4 Max with 128GB RAM running macOS 26.2

2. Verify in Terminal: sysctl kern.max_task_pmem (returns 0)

3. Open any IDE (PhpStorm, VS Code, Xcode)

4. Open any Chromium browser (Brave, Chrome)

5. Use both applications for 1-5 minutes

6. RESULT: One or more apps will suddenly quit

CRASH SEQUENCE CAPTURED IN LOGS:

1. T+0.000s - PhpStorm + Brave running normally

2. T+0.200s - runningboardd calls MEMORYSTATUS_CMD_CONVERT_MEMLIMIT_MB

3. T+0.201s - Kernel returns EINVAL (error 22)

4. T+0.300s - runningboardd invalidates PhpStorm assertions

5. T+0.400s - PhpStorm process terminated

6. T+0.500s - Connected services cascade disconnect

ATTEMPTED FIXES (NONE WORKED):

- Reinstalled macOS 26.2 (clean install)

- Reset NVRAM

- Rebuilt Launch Services database

- Cleared system caches

- Disabled Spotlight

- Safe Mode boot

- Apple Hardware Diagnostics - PASSED

ADDITIONAL OBSERVATION:

System logs show thousands of NI0 NO_ACCESS kernel errors per hour:

kernel: Ignored NI0 NI0 niGeneral 1 NO_ACCESS error (0x00000010)

Hardware diagnostics passed, suggesting firmware issue.

HYPOTHESIS:

The kernel's memory limit calculation in memorystatus_control() may have an overflow or incorrect calculation when hw.memsize is 128GB (137438953472 bytes), causing kern.max_task_pmem to be set to 0.

Possible code location: bsd/kern/kern_memorystatus.c in XNU kernel

REQUESTED FIX:

1. Investigate why kern.max_task_pmem is 0 on M4 Max 128GB systems

2. Fix MEMORYSTATUS_CMD_CONVERT_MEMLIMIT_MB to handle 128GB correctly

3. Release patch in macOS 26.2.1 or 26.3

ATTACHMENTS:

- sysdiagnose archive

- KEY_ERRORS.log - exact kernel error messages

- memory_events_sanitized.log - full jetsam/memory logs

- runningboard_sanitized.log - process management logs

- SYSTEM_INFO.txt - hardware configuration

- ni0_errors_sample.log - hardware interconnect errors

[Edited by Moderator]