Linux-RISC-V Archive on lore.kernel.org
 help / color / mirror / Atom feed
From: Siddharth Chintamaneni <sidchintamaneni@gmail.com>
To: bpf@vger.kernel.org
Cc: Siddharth Chintamaneni <sidchintamaneni@gmail.com>,
	Jeremy Jean <jeremy.jean@oss.cyber.gouv.fr>,
	Alexei Starovoitov <ast@kernel.org>,
	Daniel Borkmann <daniel@iogearbox.net>,
	John Fastabend <john.fastabend@gmail.com>,
	Andrii Nakryiko <andrii@kernel.org>,
	Eduard Zingerman <eddyz87@gmail.com>,
	Kumar Kartikeya Dwivedi <memxor@gmail.com>,
	Martin KaFai Lau <martin.lau@linux.dev>,
	Song Liu <song@kernel.org>,
	Yonghong Song <yonghong.song@linux.dev>,
	Jiri Olsa <jolsa@kernel.org>,
	Emil Tsalapatis <emil@etsalapatis.com>,
	Ihor Solodrai <ihor.solodrai@linux.dev>,
	Anton Protopopov <a.s.protopopov@gmail.com>,
	Puranjay Mohan <puranjay@kernel.org>,
	linuxppc-dev@lists.ozlabs.org, linux-s390@vger.kernel.org,
	linux-riscv@lists.infradead.org, rlmenge@gmail.com,
	hargar@linux.microsoft.com, apais@microsoft.com
Subject: [PATCH bpf-next v1 4/7] bpf, powerpc64: Use resolved pointer for timed may_goto
Date: Fri,  4 Sep 2026 19:51:29 +0000	[thread overview]
Message-ID: <20260904195132.141068-5-sidchintamaneni@gmail.com> (raw)
In-Reply-To: <20260904195132.141068-1-sidchintamaneni@gmail.com>

The timed may_goto fixup now passes the resolved counter pointer through
BPF_REG_AX instead of a stack offset.

Copy the pointer directly into the first argument register rather than
adding it to the BPF frame pointer again.

Fixes: b55b6b9ad76c ("powerpc64/bpf: Add powerpc64 JIT support for timed may_goto")
Reported-by: Jeremy Jean <jeremy.jean@oss.cyber.gouv.fr>
Link: https://lore.kernel.org/all/20260824213158.3755932-2-Jeremy.Jean@oss.cyber.gouv.fr/
Assisted-by: Copilot:gpt-5.6-sol
Signed-off-by: Siddharth Chintamaneni <sidchintamaneni@gmail.com>
---
 arch/powerpc/net/bpf_timed_may_goto.S | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/arch/powerpc/net/bpf_timed_may_goto.S b/arch/powerpc/net/bpf_timed_may_goto.S
index 84ecf6fa7f5d..d88825dd34fe 100644
--- a/arch/powerpc/net/bpf_timed_may_goto.S
+++ b/arch/powerpc/net/bpf_timed_may_goto.S
@@ -8,7 +8,7 @@
  * arch_bpf_timed_may_goto() trampoline for powerpc64
  *
  * Custom BPF convention (verifier/JIT):
- *	- input:  stack offset in BPF_REG_AX (r12)
+ *	- input:  count and timestamp pointer in BPF_REG_AX (r12)
  *	- output: updated count in BPF_REG_AX (r12)
  *
  * Call bpf_check_timed_may_goto(ptr) with normal powerpc64 ABI:
@@ -32,10 +32,10 @@ SYM_FUNC_START(arch_bpf_timed_may_goto)
 	std     r8, 72(r1)
 
 	/*
-	 * r3 = BPF_REG_FP + BPF_REG_AX
-	 * BPF_REG_FP is r31; BPF_REG_AX is r12 (stack offset in bytes).
+	 * BPF_REG_AX (r12) contains the count and timestamp pointer; pass it as
+	 * the first argument in r3.
 	 */
-	add     r3, r31, r12
+	mr      r3, r12
 	bl      CFUNC(bpf_check_timed_may_goto)
 
 	/* Put return value back into AX */
-- 
2.43.0

_______________________________________________
linux-riscv mailing list
linux-riscv@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-riscv

  parent reply	other threads:[~2026-09-04 19:51 UTC|newest]

Thread overview: 11+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-09-04 19:51 [PATCH bpf-next v1 0/7] Fix timed may_goto with private stacks Siddharth Chintamaneni
2026-09-04 19:51 ` [PATCH bpf-next v1 1/7] bpf: Fix timed may_goto stack pointer for " Siddharth Chintamaneni
2026-09-04 19:51 ` [PATCH bpf-next v1 2/7] bpf, x86: Use resolved pointer for timed may_goto Siddharth Chintamaneni
2026-09-04 20:33   ` bot+bpf-ci
2026-09-04 19:51 ` [PATCH bpf-next v1 3/7] bpf, arm64: " Siddharth Chintamaneni
2026-09-04 19:51 ` Siddharth Chintamaneni [this message]
2026-09-04 19:51 ` [PATCH bpf-next v1 5/7] bpf, riscv: " Siddharth Chintamaneni
2026-09-04 20:33   ` bot+bpf-ci
2026-09-04 19:51 ` [PATCH bpf-next v1 6/7] bpf, s390: " Siddharth Chintamaneni
2026-09-04 20:33   ` bot+bpf-ci
2026-09-04 19:51 ` [PATCH bpf-next v1 7/7] selftests/bpf: Test timed may_goto with private stacks Siddharth Chintamaneni

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=20260904195132.141068-5-sidchintamaneni@gmail.com \
    --to=sidchintamaneni@gmail.com \
    --cc=a.s.protopopov@gmail.com \
    --cc=andrii@kernel.org \
    --cc=apais@microsoft.com \
    --cc=ast@kernel.org \
    --cc=bpf@vger.kernel.org \
    --cc=daniel@iogearbox.net \
    --cc=eddyz87@gmail.com \
    --cc=emil@etsalapatis.com \
    --cc=hargar@linux.microsoft.com \
    --cc=ihor.solodrai@linux.dev \
    --cc=jeremy.jean@oss.cyber.gouv.fr \
    --cc=john.fastabend@gmail.com \
    --cc=jolsa@kernel.org \
    --cc=linux-riscv@lists.infradead.org \
    --cc=linux-s390@vger.kernel.org \
    --cc=linuxppc-dev@lists.ozlabs.org \
    --cc=martin.lau@linux.dev \
    --cc=memxor@gmail.com \
    --cc=puranjay@kernel.org \
    --cc=rlmenge@gmail.com \
    --cc=song@kernel.org \
    --cc=yonghong.song@linux.dev \
    /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