From: Christophe Leroy <christophe.leroy@csgroup.eu>
To: "Naveen N. Rao" <naveen.n.rao@linux.vnet.ibm.com>,
bpf@vger.kernel.org, linuxppc-dev@lists.ozlabs.org
Cc: Brendan Jackman <jackmanb@google.com>,
Jiri Olsa <jolsa@redhat.com>,
Alexei Starovoitov <alexei.starovoitov@gmail.com>,
Daniel Borkmann <daniel@iogearbox.net>
Subject: Re: [PATCH 2/2] powerpc/bpf: Reject atomic ops in ppc32 JIT
Date: Thu, 1 Jul 2021 18:36:11 +0200 [thread overview]
Message-ID: <f05821f6-816f-c9bf-faa9-015e11f25a46@csgroup.eu> (raw)
In-Reply-To: <426699046d89fe50f66ecf74bd31c01eda976ba5.1625145429.git.naveen.n.rao@linux.vnet.ibm.com>
Le 01/07/2021 à 17:08, Naveen N. Rao a écrit :
> Commit 91c960b0056672 ("bpf: Rename BPF_XADD and prepare to encode other
> atomics in .imm") converted BPF_XADD to BPF_ATOMIC and updated all JIT
> implementations to reject JIT'ing instructions with an immediate value
> different from BPF_ADD. However, ppc32 BPF JIT was implemented around
> the same time and didn't include the same change. Update the ppc32 JIT
> accordingly.
>
> Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Shouldn't it also include a Fixes tag and stable Cc as PPC32 eBPF was added in 5.13 ?
Fixes: 51c66ad849a7 ("powerpc/bpf: Implement extended BPF on PPC32")
Cc: stable@vger.kernel.org
> ---
> arch/powerpc/net/bpf_jit_comp32.c | 14 +++++++++++---
> 1 file changed, 11 insertions(+), 3 deletions(-)
>
> diff --git a/arch/powerpc/net/bpf_jit_comp32.c b/arch/powerpc/net/bpf_jit_comp32.c
> index cbe5b399ed869d..91c990335a16c9 100644
> --- a/arch/powerpc/net/bpf_jit_comp32.c
> +++ b/arch/powerpc/net/bpf_jit_comp32.c
> @@ -773,9 +773,17 @@ int bpf_jit_build_body(struct bpf_prog *fp, u32 *image, struct codegen_context *
> break;
>
> /*
> - * BPF_STX XADD (atomic_add)
> + * BPF_STX ATOMIC (atomic ops)
> */
> - case BPF_STX | BPF_XADD | BPF_W: /* *(u32 *)(dst + off) += src */
> + case BPF_STX | BPF_ATOMIC | BPF_W:
> + if (imm != BPF_ADD) {
> + pr_err_ratelimited(
> + "eBPF filter atomic op code %02x (@%d) unsupported\n", code, i);
> + return -ENOTSUPP;
> + }
> +
> + /* *(u32 *)(dst + off) += src */
> +
> bpf_set_seen_register(ctx, tmp_reg);
> /* Get offset into TMP_REG */
> EMIT(PPC_RAW_LI(tmp_reg, off));
> @@ -789,7 +797,7 @@ int bpf_jit_build_body(struct bpf_prog *fp, u32 *image, struct codegen_context *
> PPC_BCC_SHORT(COND_NE, (ctx->idx - 3) * 4);
> break;
>
> - case BPF_STX | BPF_XADD | BPF_DW: /* *(u64 *)(dst + off) += src */
> + case BPF_STX | BPF_ATOMIC | BPF_DW: /* *(u64 *)(dst + off) += src */
> return -EOPNOTSUPP;
>
> /*
>
next prev parent reply other threads:[~2021-07-01 16:36 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-07-01 15:08 [PATCH 0/2] powerpc/bpf: Fix issue with atomic ops Naveen N. Rao
2021-07-01 15:08 ` [PATCH 1/2] powerpc/bpf: Fix detecting BPF atomic instructions Naveen N. Rao
2021-07-01 16:03 ` Alexei Starovoitov
2021-07-01 19:32 ` Naveen N. Rao
2021-07-01 19:33 ` Alexei Starovoitov
2021-07-02 10:26 ` Jiri Olsa
2021-07-01 15:08 ` [PATCH 2/2] powerpc/bpf: Reject atomic ops in ppc32 JIT Naveen N. Rao
2021-07-01 16:36 ` Christophe Leroy [this message]
2021-07-01 19:36 ` Naveen N. Rao
2021-07-06 10:52 ` [PATCH 0/2] powerpc/bpf: Fix issue with atomic ops Michael Ellerman
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=f05821f6-816f-c9bf-faa9-015e11f25a46@csgroup.eu \
--to=christophe.leroy@csgroup.eu \
--cc=alexei.starovoitov@gmail.com \
--cc=bpf@vger.kernel.org \
--cc=daniel@iogearbox.net \
--cc=jackmanb@google.com \
--cc=jolsa@redhat.com \
--cc=linuxppc-dev@lists.ozlabs.org \
--cc=naveen.n.rao@linux.vnet.ibm.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).