From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 87AEF242D9B; Wed, 25 Feb 2026 01:28:54 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1771982934; cv=none; b=EttuCBKANlLpArICF7Z0+OgOI6rOyjclV4z0Fthl7WFedBeFDS36TVLly7KMWYHyohFoeZSXyb87cWYjgGs3ldgxgLItp8ZMsgVUDLLa5CEXca7aA3n0nHbN3gk29ChSPXdHwD9Io2+vc4crYIfbB4xOagKPcpuW5t6St/peOAI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1771982934; c=relaxed/simple; bh=1RSpnshWRazYQOZWQjDe7ggH6pWBXphy8N1KjdhNSjc=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=FT+aL8MhMZHEEcl+aSUwBD4wsdIzlHM185OcCI+zGjyF3AsMqrmfPzZRKA+l1WGZsxvNyK+HnGn8/vzxeVAFJlBDFCg4iv5M5kYE/inPCO+enzrNTdVnUtiQW66kk9DCedvr/eaeg70TNGShVH7ltJpYQsVQY72q2awZCAkIDkc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=g9MLnpeR; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="g9MLnpeR" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 4C01DC116D0; Wed, 25 Feb 2026 01:28:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1771982934; bh=1RSpnshWRazYQOZWQjDe7ggH6pWBXphy8N1KjdhNSjc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=g9MLnpeR4zQ1UU7DTDPK9tR2CRvH3JS186cems+jKayPzRhviev2hpaEBmvpba9Dv hH+/16S1DX8DNQ5HzGSnkPMUAa0hMSFGnpXh7SoQHKrhhq6QZnvh92iUn37L6p1jhu BHQwuXGzthb/Nowi+D+kwnbYlGaVgARnSSDVw9KA= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Jiri Olsa , Andrii Nakryiko , "Steven Rostedt (Google)" , Sasha Levin Subject: [PATCH 6.19 111/781] x86/fgraph: Fix return_to_handler regs.rsp value Date: Tue, 24 Feb 2026 17:13:40 -0800 Message-ID: <20260225012402.402093716@linuxfoundation.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260225012359.695468795@linuxfoundation.org> References: <20260225012359.695468795@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.19-stable review patch. If anyone has any objections, please let me know. ------------------ From: Jiri Olsa [ Upstream commit 8bc11700e0d23d4fdb7d8d5a73b2e95de427cabc ] The previous change (Fixes commit) messed up the rsp register value, which is wrong because it's already adjusted with FRAME_SIZE, we need the original rsp value. This change does not affect fprobe current kernel unwind, the !perf_hw_regs path perf_callchain_kernel: if (perf_hw_regs(regs)) { if (perf_callchain_store(entry, regs->ip)) return; unwind_start(&state, current, regs, NULL); } else { unwind_start(&state, current, NULL, (void *)regs->sp); } which uses pt_regs.sp as first_frame boundary (FRAME_SIZE shift makes no difference, unwind stil stops at the right frame). This change fixes the other path when we want to unwind directly from pt_regs sp/fp/ip state, which is coming in following change. Fixes: 20a0bc10272f ("x86/fgraph,bpf: Fix stack ORC unwind from kprobe_multi return probe") Signed-off-by: Jiri Olsa Signed-off-by: Andrii Nakryiko Reviewed-by: Steven Rostedt (Google) Link: https://lore.kernel.org/bpf/20260126211837.472802-2-jolsa@kernel.org Signed-off-by: Sasha Levin --- arch/x86/kernel/ftrace_64.S | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/arch/x86/kernel/ftrace_64.S b/arch/x86/kernel/ftrace_64.S index a132608265f6c..62c1c93aa1c6a 100644 --- a/arch/x86/kernel/ftrace_64.S +++ b/arch/x86/kernel/ftrace_64.S @@ -364,6 +364,9 @@ SYM_CODE_START(return_to_handler) UNWIND_HINT_UNDEFINED ANNOTATE_NOENDBR + /* Store original rsp for pt_regs.sp value. */ + movq %rsp, %rdi + /* Restore return_to_handler value that got eaten by previous ret instruction. */ subq $8, %rsp UNWIND_HINT_FUNC @@ -374,7 +377,7 @@ SYM_CODE_START(return_to_handler) movq %rax, RAX(%rsp) movq %rdx, RDX(%rsp) movq %rbp, RBP(%rsp) - movq %rsp, RSP(%rsp) + movq %rdi, RSP(%rsp) movq %rsp, %rdi call ftrace_return_to_handler -- 2.51.0