[PATCH][RESEND] x86/mm: Harden copy_from_kernel_nofault_allowed() to prevent false MCEs'

[Seiji Nishikawa]

Hello,

I’m following up on the patch I submitted on February 5th:
 https://lore.kernel.org/lkml/20250205065336.440890-1-snishika@xxxxxxxxxx

It’s been over 8 weeks, and I haven’t received any feedback. Just wanted to check whether this was overlooked, or if any comments or suggestions are pending.

The patch not only covers addresses within the VSYSCALL_ADDR + PAGE_SIZE range as before, but also includes misaligned addresses from the 4 pages below it, to catch misaligned or speculative accesses that might otherwise bypass the existing check.

If this approach seems inappropriate or there’s a preferred alternative, I’d really appreciate your guidance.

Thanks in advance for your time and feedback.

Best regards,  
Seiji Nishikawa