Re: [PATCH bpf v3] powerpc/bpf: enforce full ordering for ATOMIC operations with BPF_FETCH

Michael Ellerman
2024-06-03T02:45:54Z

On Mon, 13 May 2024 10:02:48 +0000, Puranjay Mohan wrote:
> The Linux Kernel Memory Model [1][2] requires RMW operations that have a
> return value to be fully ordered.
>
> BPF atomic operations with BPF_FETCH (including BPF_XCHG and
> BPF_CMPXCHG) return a value back so they need to be JITed to fully
> ordered operations. POWERPC currently emits relaxed operations for
> these.
>
> [...]

Applied to powerpc/fixes.

[1/1] powerpc/bpf: enforce full ordering for ATOMIC operations with BPF_FETCH
https://git.kernel.org/powerpc/c/b1e7cee96127468c2483cf10c2899c9b5cf79bf8

cheers