Re: [PATCH v1 3/3] arch/powerpc/net/bpf: Basic EBPF support

["Naveen N. Rao" <naveen.n.rao@linux.vnet.ibm.com>]

> arch/powerpc/net/bpf: Basic EBPF support

Perhaps:
powerpc/bpf: Set JIT memory read-only

On 2017/08/01 09:25PM, Balbir Singh wrote:
> Signed-off-by: Balbir Singh <bsingharora@gmail.com>
> ---
>  arch/powerpc/net/bpf_jit_comp64.c | 13 +------------
>  1 file changed, 1 insertion(+), 12 deletions(-)
> 
> diff --git a/arch/powerpc/net/bpf_jit_comp64.c b/arch/powerpc/net/bpf_jit_comp64.c
> index 861c5af..d81110e 100644
> --- a/arch/powerpc/net/bpf_jit_comp64.c
> +++ b/arch/powerpc/net/bpf_jit_comp64.c
> @@ -1054,6 +1054,7 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *fp)
>  	fp->jited = 1;
>  	fp->jited_len = alloclen;
> 
> +	bpf_jit_binary_lock_ro(bpf_hdr);
>  	bpf_flush_icache(bpf_hdr, (u8 *)bpf_hdr + (bpf_hdr->pages * PAGE_SIZE));

Should we call bpf_flush_icache() _before_ locking the memory?

Thanks,
Naveen

> 
>  out:
> @@ -1064,15 +1065,3 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *fp)
> 
>  	return fp;
>  }
> -
> -/* Overriding bpf_jit_free() as we don't set images read-only. */
> -void bpf_jit_free(struct bpf_prog *fp)
> -{
> -	unsigned long addr = (unsigned long)fp->bpf_func & PAGE_MASK;
> -	struct bpf_binary_header *bpf_hdr = (void *)addr;
> -
> -	if (fp->jited)
> -		bpf_jit_binary_free(bpf_hdr);
> -
> -	bpf_prog_unlock_free(fp);
> -}
> -- 
> 2.9.4
>