mm: Add CONFIG_MM_NODE_PENDING configuration

[W-M-R]

Summary

After it is enabled, the preceding member of the next node will no longer belong to the valid area of the previous alloc node.
Due to the existence of the preceding member, the memory block size of the node can only be aligned with sizeof(mmsize_t).
This configuration will be applied in the following scenarios:
ARM64 MTE hardware tag KASan, which requires the tag's memory address to be 16-byte aligned and the memory size must also be 16-byte aligned

Impact

The new feature arm64 MTE is added, "#15461" requires that the allocated block address must be 16-byte aligned and the size must also be 16-byte aligned. Our current memory management does not meet the requirements.

Testing

CI

[nuttxpr]

[Experimental Bot, please feedback here]

This PR does not fully meet the NuttX requirements yet. While it provides a basic description of the change, it lacks crucial details in the Impact and Testing sections.

Here's a breakdown of what's missing:

• Summary: While it describes what is changed, it's missing why. What problem does aligning memory blocks to MM_ALIGN solve? Is this a performance optimization, a bug fix, or something else? It needs more context. Mention any related issues.

• Impact: This section is essentially empty. It needs to be filled out completely. Consider the following:

  • Is this a new feature? If so, explicitly state that.
  • User Impact: Will users need to change any configuration options? Will existing applications break?
  • Build Impact: Will users need to change anything in their build system?
  • Hardware Impact: Does this change affect specific architectures or boards?
  • Documentation Impact: Does the documentation need to be updated to reflect this change? If so, has the documentation been updated in this PR or another?
  • Security Impact: Are there any potential security implications of this change? Even if the answer is no, explicitly state that.
  • Compatibility Impact: Does this change break backwards compatibility?

• Testing: This section is also largely empty. It needs concrete details:

  • Build Host: Specify the operating system, CPU architecture, and compiler version used. (e.g., "Linux x86_64, GCC 12.1")
  • Target: Specify the architecture and board/configuration tested. (e.g., "sim:qemu-arm")
  • Logs: Provide actual logs from before and after the change. These logs should demonstrate that the change has the intended effect. Show how memory allocation behaves differently now. Don't just leave the placeholder text.

In short, the PR needs to be significantly more detailed before it can be properly reviewed. Filling in the missing information in the Impact and Testing sections is crucial. The Summary section could also benefit from more context.

[yamt]

what are you trying to fix with this?

[W-M-R]

what are you trying to fix with this?

The new feature arm64 MTE is added, "#15461" requires that the allocated block address must be 16-byte aligned and the size must also be 16-byte aligned. Our current memory management does not meet the requirements.Adding this alignment can solve this problem