From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pg1-f202.google.com (mail-pg1-f202.google.com [209.85.215.202]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 035A7396B6D for ; Mon, 6 Apr 2026 18:50:25 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.215.202 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1775501427; cv=none; b=n7iXig1pgBRJwvOLui4wANov6go0qDkeu53CvrR3g9sYUfdWO2h6KeA+gMpiVbRJHEEwAUHMWcBk182waVOdxLoD3j3P2ZAR8nnIuS9mLIH0qy/3wyvhqd9E+BWAHaMFOGFRyihq32r367UxZLSsOToG/4hqRKl6QeQn+c3FvsY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1775501427; c=relaxed/simple; bh=932M4EHTQvdCDGtwUM/Vrh9msTuo3oJ8/i3ljoodip0=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=T3PvJTGQBsg/ska/RzAvGbdiJeHye0kxq6Lgax9qThry/I++YGeP7ZDvEi3l3gos5Htg2nuIEzcFN2Ib7OXwMVdSiy1hXaCQJrZIF0nTdhfWHcHE0tMtGd0qwggPxba96s2hFzMaHe6obyd/sVUC5UwjpcZRXOTMd2bM3Lv+g70= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--dylanbhatch.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=Zs/7F3qF; arc=none smtp.client-ip=209.85.215.202 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--dylanbhatch.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="Zs/7F3qF" Received: by mail-pg1-f202.google.com with SMTP id 41be03b00d2f7-c7424d91b2dso2099808a12.1 for ; Mon, 06 Apr 2026 11:50:25 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20251104; t=1775501425; x=1776106225; darn=vger.kernel.org; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=MdqPVoHRwnHco6kAfBJ1zgi0YfCPZYijdJUSHSI46+Y=; b=Zs/7F3qFENa1CeApZhnBxldxz+NPDMjEOdU0C5DNbQ9UrThdKrHmL1UFXUba1/Pjvv THegru/w7KvZP4JLCX+R504SRbcnVsx5l9ZGBosgRbpp5Ks0UcdxwYEHO7hMZrZo2ESg HXFxX4H3PRH4KzJhN4Bs1DK0ApXOvkhBDMCBEcXDn/HNYFq2RO0vjD+h3MGD+RBo/GF6 p2t07Bc4dNB1XT62mv+FGOxwB3P3zHdLWxyCN6BSwr0Tm0UWPOV3fBSREvn/RxfLkzJr SZ2I7RAQRxmFdH84JXeiro5beG7Qe7G+HdrgI8noHahg84P25AXYmJaKDULQo2joSwM0 32Nw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1775501425; x=1776106225; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=MdqPVoHRwnHco6kAfBJ1zgi0YfCPZYijdJUSHSI46+Y=; b=MbPIXV3jf2qnhr+s/JBt7tLOQv0ur/Wr8z8m9KX40oMuWEiR6no+uL+PwNDpXi+HKM 2tlZv3lAbJs3sEBqnvL5YehPgVa9EUZ5CbQuhwJaahtbsLp57BjRsMkmXI/e/0WTyBj3 cUrLsZn+DEGStru0VniFmuiOaQSxjuw3eCXiCP55Gv2FG9JR1oDrLH1ieDacwgCGyFT1 dcvv92Y8KxTG9SAXPaqRNwkGzWsn4tyEllJW4fZxAyugxx0syj/qe0Wj11sPKFdrZzh3 sT8dncqfIVwZYDtIuLRf4UsbqQ4GWwhFCDv/XoDB82b8a1VYpa17nwgQXy+vERbGeS37 WDTg== X-Forwarded-Encrypted: i=1; AJvYcCXX9x8gzomM8xaoRvS5+Qx62rjc5VRd4KJe2iHUxfxp204Fx1RRTUmZTrBvrnkS+og2+DqH+GDE1yk0A0kE@vger.kernel.org X-Gm-Message-State: AOJu0YzqXgb5nwjo5sRx0fxbhx9XYcyk7CGP1o8zqqTgGxJdH8apMF98 2KWSvS0aYpqlyXmY9kI+CIM5bQUllcxK+5cY3pafWots2KW2NbKul5R84KZw6ZTFw+zpRPoZxxR jEG0ND1LNIMgORoqCjtL56YnTIw== X-Received: from pfo22.prod.google.com ([2002:a05:6a00:2f6:b0:829:a228:6330]) (user=dylanbhatch job=prod-delivery.src-stubby-dispatcher) by 2002:a05:6a00:a0f:b0:829:8a84:b9fc with SMTP id d2e1a72fcca58-82d0da33e8fmr12546186b3a.8.1775501425116; Mon, 06 Apr 2026 11:50:25 -0700 (PDT) Date: Mon, 6 Apr 2026 18:49:56 +0000 In-Reply-To: <20260406185000.1378082-1-dylanbhatch@google.com> Precedence: bulk X-Mailing-List: live-patching@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20260406185000.1378082-1-dylanbhatch@google.com> X-Mailer: git-send-email 2.53.0.1213.gd9a14994de-goog Message-ID: <20260406185000.1378082-5-dylanbhatch@google.com> Subject: [PATCH v3 4/8] sframe: Provide PC lookup for vmlinux .sframe section. From: Dylan Hatch To: Roman Gushchin , Weinan Liu , Will Deacon , Josh Poimboeuf , Indu Bhagat , Peter Zijlstra , Steven Rostedt , Catalin Marinas , Jiri Kosina Cc: Dylan Hatch , Mark Rutland , Prasanna Kumar T S M , Puranjay Mohan , Song Liu , joe.lawrence@redhat.com, linux-toolchains@vger.kernel.org, linux-kernel@vger.kernel.org, live-patching@vger.kernel.org, Jens Remus , linux-arm-kernel@lists.infradead.org Content-Type: text/plain; charset="UTF-8" With SFRAME_UNWINDER, read in the .sframe section at boot. This provides unwind data as an alternative/supplement to frame pointer-based unwinding. Signed-off-by: Dylan Hatch --- arch/arm64/kernel/setup.c | 2 ++ include/linux/sframe.h | 14 ++++++++++++++ kernel/unwind/sframe.c | 39 +++++++++++++++++++++++++++++++++++++++ 3 files changed, 55 insertions(+) diff --git a/arch/arm64/kernel/setup.c b/arch/arm64/kernel/setup.c index 23c05dc7a8f2..4a633bc7aefb 100644 --- a/arch/arm64/kernel/setup.c +++ b/arch/arm64/kernel/setup.c @@ -32,6 +32,7 @@ #include #include #include +#include #include #include @@ -375,6 +376,7 @@ void __init __no_sanitize_address setup_arch(char **cmdline_p) "This indicates a broken bootloader or old kernel\n", boot_args[1], boot_args[2], boot_args[3]); } + init_sframe_table(); } static inline bool cpu_can_disable(unsigned int cpu) diff --git a/include/linux/sframe.h b/include/linux/sframe.h index 673b9edfc921..905775c3fde2 100644 --- a/include/linux/sframe.h +++ b/include/linux/sframe.h @@ -109,4 +109,18 @@ static inline int sframe_find_user(unsigned long ip, struct unwind_frame *frame) #endif /* CONFIG_HAVE_UNWIND_USER_SFRAME */ +#ifdef CONFIG_SFRAME_UNWINDER + +void __init init_sframe_table(void); +void sframe_module_init(struct module *mod, void *sframe, size_t sframe_size, + void *text, size_t text_size); + +extern int sframe_find_kernel(unsigned long ip, struct unwind_frame *frame); + +#else + +static inline void __init init_sframe_table(void) {} + +#endif /* CONFIG_SFRAME_UNWINDER */ + #endif /* _LINUX_SFRAME_H */ diff --git a/kernel/unwind/sframe.c b/kernel/unwind/sframe.c index cad4384dfb4f..321d0615aec7 100644 --- a/kernel/unwind/sframe.c +++ b/kernel/unwind/sframe.c @@ -13,10 +13,23 @@ #include #include #include +#ifdef CONFIG_SFRAME_UNWINDER +#include +#endif #include "sframe.h" #include "sframe_debug.h" +#ifdef CONFIG_SFRAME_UNWINDER + +extern char __start_sframe_header[]; +extern char __stop_sframe_header[]; + +static bool sframe_init __ro_after_init; +static struct sframe_section kernel_sfsec __ro_after_init; + +#endif /* CONFIG_SFRAME_UNWINDER */ + struct sframe_fde_internal { unsigned long func_addr; u32 func_size; @@ -930,3 +943,29 @@ void sframe_free_mm(struct mm_struct *mm) } #endif /* CONFIG_HAVE_UNWIND_USER_SFRAME */ + +#ifdef CONFIG_SFRAME_UNWINDER + +int sframe_find_kernel(unsigned long ip, struct unwind_frame *frame) +{ + if (!frame || !sframe_init) + return -EINVAL; + + return __sframe_find(&kernel_sfsec, ip, frame); +} + +void __init init_sframe_table(void) +{ + kernel_sfsec.sec_type = SFRAME_KERNEL; + kernel_sfsec.sframe_start = (unsigned long)__start_sframe_header; + kernel_sfsec.sframe_end = (unsigned long)__stop_sframe_header; + kernel_sfsec.text_start = (unsigned long)_stext; + kernel_sfsec.text_end = (unsigned long)_etext; + + if (WARN_ON(sframe_read_header(&kernel_sfsec))) + return; + + sframe_init = true; +} + +#endif /* CONFIG_SFRAME_UNWINDER */ -- 2.53.0.1213.gd9a14994de-goog