Re: [PATCH v5] powerpc/uprobes: Validation for prefixed instruction

[Michael Ellerman]

On Thu, 11 Mar 2021 14:45:38 +0530, Ravi Bangoria wrote:
> As per ISA 3.1, prefixed instruction should not cross 64-byte
> boundary. So don't allow Uprobe on such prefixed instruction.
> 
> There are two ways probed instruction is changed in mapped pages.
> First, when Uprobe is activated, it searches for all the relevant
> pages and replace instruction in them. In this case, if that probe
> is on the 64-byte unaligned prefixed instruction, error out
> directly. Second, when Uprobe is already active and user maps a
> relevant page via mmap(), instruction is replaced via mmap() code
> path. But because Uprobe is invalid, entire mmap() operation can
> not be stopped. In this case just print an error and continue.

Applied to powerpc/next.

[1/1] powerpc/uprobes: Validation for prefixed instruction
      https://git.kernel.org/powerpc/c/d943bc742a6aabc578b6b62a713ceedf8bf16623

cheers