From nobody Mon Feb 9 12:24:44 2026 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 67C1027A445 for ; Thu, 1 May 2025 22:55:29 +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=1746140131; cv=none; b=g+xb+BTwwr53h/UJuUZG+jicvfEuWfGRU/3Czn7z0oEmbEjelk36Nh6gRq2Aerjz6QkjXoHDQxn8xuHrRL32kXxcDfwaYbuKLD+wkWAkkSm0zW9/1TbwdLUZCDEi3c+nkH7aeFlrWOWXGpbsXgbJQRmF50jFLzcqMPVgCivQLW4= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1746140131; c=relaxed/simple; bh=Np7xEzYoeKxcCCUuRKxqAowl8VIBt9eHtB6TF/VGX4g=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=WVGQjzpKNoxK5jj4OLyZiUbA3EKLOHLlTSsJQp9IaUBTqwL4cN0nwH5LHQUBfIV5DweVVKIsAlbNQ17TmD1sQ+vXDgQjQgU6Wq10H/Q9W8pPdkFzOXA0wqYAo+qFwQ6bZtuZU5zMT67tM2n8BvccJtsJERcejC9G6yyFNIvHTGA= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--changyuanl.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=xF3A5IsQ; 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--changyuanl.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="xF3A5IsQ" Received: by mail-pg1-f202.google.com with SMTP id 41be03b00d2f7-b1b2fa98c39so1464078a12.2 for ; Thu, 01 May 2025 15:55:29 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1746140129; x=1746744929; 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=GwWO2FOvlius8r+9F7qsaJRBJWjTTO3gcmkaNJYk24k=; b=xF3A5IsQnhzquuZyODSLHlrX9bkNxwGgdbdWyg1x+S55Z9XDUsYivugGGgOAxd+1qP Qm6LINc794jLoIrH3rcJVB7k5ZNYssYUvCJDONkZILxIoR0NLqwI7dOQ8Xz8ypJvk0y6 8g8Vzn+yTdPlVD3XhUMh3Lj3luImUIO4viIEulq07AZIL+e/bjp6YGkjNm98PNWBeG20 48/Np7jl9rDwELFp69b4aOSPVk+ajnOEUPsmX1YwDyu5Yvhi+E6VNx9Y9EV/ebOFCkq2 qrw3kcvNwuGivBylMqPG8taR1XDeNmwxKw9Dw9FMIiNM27vkliusTIG+kgoo0E5b9A2w wE4Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1746140129; x=1746744929; 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=GwWO2FOvlius8r+9F7qsaJRBJWjTTO3gcmkaNJYk24k=; b=fWAGl9Ego5CWlUI8B9apfuJ/zLPn+VbXTps1n4yHSjNlM1+4CnaGgBPKwQJAZEnu55 6X429/dvzbWZRMY/5FxGrymZgr1AbUmD5iFH+SrsE8xzK15QIzV06Zwh47o6X1EO47wL D7o4G7yjkwN9dNiveiX2Lv6b3ympPeMXiLCzdpvi0HkUnAAhKD54sXBzIfMfpzS1o616 1fyleCa/Wiwr9uSTHk7j2eCHkNMW/oKj60GrVbxyDu46O5xvcbpxij3X0zhiTZM+8J5+ Xv5RpzyMumIOzUIrusk7ZqLwDoF6iGxpU8THLcPNXHFL7bzeVRlO1XSyGXFe9jNsjhMy Knlw== X-Gm-Message-State: AOJu0YwuC2VOasGAWnxAkKc5ABPyKd7Dcvautkvf2eqr69fJ/Jrf0I9Z xynNiDkquvHe/+rDJBKk04eCT7XMAdWBWbHP1naN6sDDkz5YTjuqxgDG1QieTcoxZNpC3UnlPCn Mo2iZ4yD2awA91I0AwBebBUTvfsU+kiYmZ/VSzIth3yyc8wLzMuMsL5/8cHlJKu4NslUWiqtot1 XEyo91djJMe2zlktUGHPOnEtrYXpKbbVvpioRBHmcdG/cVhX5yX1d4eIiNC9m89A== X-Google-Smtp-Source: AGHT+IHGGHQFeww3ZBllpvF8B0U8eo8S2iJ4Fy1b4zOCDt+eKf19vVsihtqaMITfWT4NmEQ5ICMAL73coQmW9XO3 X-Received: from pjee15.prod.google.com ([2002:a17:90b:578f:b0:308:65f7:9f24]) (user=changyuanl job=prod-delivery.src-stubby-dispatcher) by 2002:a17:90b:394d:b0:2fe:ba82:ca5 with SMTP id 98e67ed59e1d1-30a4e5a6761mr1350824a91.11.1746140128741; Thu, 01 May 2025 15:55:28 -0700 (PDT) Date: Thu, 1 May 2025 15:54:17 -0700 In-Reply-To: <20250501225425.635167-1-changyuanl@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20250501225425.635167-1-changyuanl@google.com> X-Mailer: git-send-email 2.49.0.906.g1f30a19c02-goog Message-ID: <20250501225425.635167-11-changyuanl@google.com> Subject: [PATCH v7 10/18] arm64: add KHO support From: Changyuan Lyu To: linux-kernel@vger.kernel.org Cc: changyuanl@google.com, akpm@linux-foundation.org, anthony.yznaga@oracle.com, arnd@arndb.de, ashish.kalra@amd.com, benh@kernel.crashing.org, bp@alien8.de, catalin.marinas@arm.com, corbet@lwn.net, dave.hansen@linux.intel.com, devicetree@vger.kernel.org, dwmw2@infradead.org, ebiederm@xmission.com, graf@amazon.com, hpa@zytor.com, jgowans@amazon.com, kexec@lists.infradead.org, krzk@kernel.org, linux-arm-kernel@lists.infradead.org, linux-doc@vger.kernel.org, linux-mm@kvack.org, luto@kernel.org, mark.rutland@arm.com, mingo@redhat.com, pasha.tatashin@soleen.com, pbonzini@redhat.com, peterz@infradead.org, ptyadav@amazon.de, robh@kernel.org, rostedt@goodmis.org, rppt@kernel.org, saravanak@google.com, skinsburskii@linux.microsoft.com, tglx@linutronix.de, thomas.lendacky@amd.com, will@kernel.org, x86@kernel.org Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" From: Alexander Graf We now have all bits in place to support KHO kexecs. Add awareness of KHO in the kexec file as well as boot path for arm64 and adds the respective kconfig option to the architecture so that it can use KHO successfully. Changes to the "chosen" node have been sent to https://github.com/devicetree-org/dt-schema/pull/158. Signed-off-by: Alexander Graf Co-developed-by: Mike Rapoport (Microsoft) Signed-off-by: Mike Rapoport (Microsoft) Co-developed-by: Changyuan Lyu Signed-off-by: Changyuan Lyu --- arch/arm64/Kconfig | 3 +++ drivers/of/fdt.c | 34 ++++++++++++++++++++++++++++++++++ drivers/of/kexec.c | 42 ++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 79 insertions(+) diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index a182295e6f08b..34c79f4fee3f9 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -1602,6 +1602,9 @@ config ARCH_SUPPORTS_KEXEC_IMAGE_VERIFY_SIG config ARCH_DEFAULT_KEXEC_IMAGE_VERIFY_SIG def_bool y =20 +config ARCH_SUPPORTS_KEXEC_HANDOVER + def_bool y + config ARCH_SUPPORTS_CRASH_DUMP def_bool y =20 diff --git a/drivers/of/fdt.c b/drivers/of/fdt.c index aedd0e2dcd890..0edd639898a63 100644 --- a/drivers/of/fdt.c +++ b/drivers/of/fdt.c @@ -25,6 +25,7 @@ #include #include #include +#include =20 #include /* for COMMAND_LINE_SIZE */ #include @@ -875,6 +876,36 @@ void __init early_init_dt_check_for_usable_mem_range(v= oid) memblock_add(rgn[i].base, rgn[i].size); } =20 +/** + * early_init_dt_check_kho - Decode info required for kexec handover from = DT + */ +static void __init early_init_dt_check_kho(void) +{ + unsigned long node =3D chosen_node_offset; + u64 fdt_start, fdt_size, scratch_start, scratch_size; + const __be32 *p; + int l; + + if (!IS_ENABLED(CONFIG_KEXEC_HANDOVER) || (long)node < 0) + return; + + p =3D of_get_flat_dt_prop(node, "linux,kho-fdt", &l); + if (l !=3D (dt_root_addr_cells + dt_root_size_cells) * sizeof(__be32)) + return; + + fdt_start =3D dt_mem_next_cell(dt_root_addr_cells, &p); + fdt_size =3D dt_mem_next_cell(dt_root_addr_cells, &p); + + p =3D of_get_flat_dt_prop(node, "linux,kho-scratch", &l); + if (l !=3D (dt_root_addr_cells + dt_root_size_cells) * sizeof(__be32)) + return; + + scratch_start =3D dt_mem_next_cell(dt_root_addr_cells, &p); + scratch_size =3D dt_mem_next_cell(dt_root_addr_cells, &p); + + kho_populate(fdt_start, fdt_size, scratch_start, scratch_size); +} + #ifdef CONFIG_SERIAL_EARLYCON =20 int __init early_init_dt_scan_chosen_stdout(void) @@ -1169,6 +1200,9 @@ void __init early_init_dt_scan_nodes(void) =20 /* Handle linux,usable-memory-range property */ early_init_dt_check_for_usable_mem_range(); + + /* Handle kexec handover */ + early_init_dt_check_kho(); } =20 bool __init early_init_dt_scan(void *dt_virt, phys_addr_t dt_phys) diff --git a/drivers/of/kexec.c b/drivers/of/kexec.c index 5b924597a4deb..1ee2d31816aeb 100644 --- a/drivers/of/kexec.c +++ b/drivers/of/kexec.c @@ -264,6 +264,43 @@ static inline int setup_ima_buffer(const struct kimage= *image, void *fdt, } #endif /* CONFIG_IMA_KEXEC */ =20 +static int kho_add_chosen(const struct kimage *image, void *fdt, int chose= n_node) +{ + int ret =3D 0; +#ifdef CONFIG_KEXEC_HANDOVER + phys_addr_t fdt_mem =3D 0; + phys_addr_t fdt_len =3D 0; + phys_addr_t scratch_mem =3D 0; + phys_addr_t scratch_len =3D 0; + + ret =3D fdt_delprop(fdt, chosen_node, "linux,kho-fdt"); + if (ret && ret !=3D -FDT_ERR_NOTFOUND) + return ret; + ret =3D fdt_delprop(fdt, chosen_node, "linux,kho-scratch"); + if (ret && ret !=3D -FDT_ERR_NOTFOUND) + return ret; + + if (!image->kho.fdt || !image->kho.scratch) + return 0; + + fdt_mem =3D image->kho.fdt; + fdt_len =3D PAGE_SIZE; + scratch_mem =3D image->kho.scratch->mem; + scratch_len =3D image->kho.scratch->bufsz; + + pr_debug("Adding kho metadata to DT"); + + ret =3D fdt_appendprop_addrrange(fdt, 0, chosen_node, "linux,kho-fdt", + fdt_mem, fdt_len); + if (ret) + return ret; + ret =3D fdt_appendprop_addrrange(fdt, 0, chosen_node, "linux,kho-scratch", + scratch_mem, scratch_len); + +#endif /* CONFIG_KEXEC_HANDOVER */ + return ret; +} + /* * of_kexec_alloc_and_setup_fdt - Alloc and setup a new Flattened Device T= ree * @@ -414,6 +451,11 @@ void *of_kexec_alloc_and_setup_fdt(const struct kimage= *image, #endif } =20 + /* Add kho metadata if this is a KHO image */ + ret =3D kho_add_chosen(image, fdt, chosen_node); + if (ret) + goto out; + /* add bootargs */ if (cmdline) { ret =3D fdt_setprop_string(fdt, chosen_node, "bootargs", cmdline); --=20 2.49.0.906.g1f30a19c02-goog