From patchwork Thu Jan 23 01:47:30 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Nuno Das Neves X-Patchwork-Id: 13947842 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 3D443C02181 for ; Thu, 23 Jan 2025 01:51:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:References:In-Reply-To: Message-Id:Date:Subject:Cc:To:From:Reply-To:MIME-Version:Content-Type: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=6NfCLWYjzohmjwKMnEJxLhyvdS+DcJjcJ204KGwB6cM=; b=goC+x/vI6fRDJasUs1w4v80ca6 1dG/ZOkDWhVqE4JFNLBuIu/3prZuM9ygd4a37djcGWyhreN+7PiqXafQCVVlAZEYA1rjOCGd0qjE7 9ASHK/pdVudQS9FH2f8mE7g1NkAWWmgzbGWjIn2sCZB3P7y0HytPXV1UuB9tySOCmN2pNva5J7twZ fs/voCoyCu1r8ta2QnBNdOWbyxtYd4R83H2UU1WQ03ROB4TibnFZofOuylDYAIK1cw3iBBpUiG92z zC5a/D+ng63gDxaop7Jw9WsFy0l0aHjnp2k1ObB+4frYwunPMorBX8tgEdu1Bge4dNFgp5VqPu/C0 4IvZ+KUQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98 #2 (Red Hat Linux)) id 1tamNb-0000000BY1N-2l05; Thu, 23 Jan 2025 01:51:35 +0000 Received: from linux.microsoft.com ([13.77.154.182]) by bombadil.infradead.org with esmtp (Exim 4.98 #2 (Red Hat Linux)) id 1tamJm-0000000BX4h-3wyS for linux-arm-kernel@lists.infradead.org; Thu, 23 Jan 2025 01:47:40 +0000 Received: from linuxonhyperv3.guj3yctzbm1etfxqx2vob5hsef.xx.internal.cloudapp.net (linux.microsoft.com [13.77.154.182]) by linux.microsoft.com (Postfix) with ESMTPSA id BBB51204608E; Wed, 22 Jan 2025 17:47:37 -0800 (PST) DKIM-Filter: OpenDKIM Filter v2.11.0 linux.microsoft.com BBB51204608E DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.microsoft.com; s=default; t=1737596857; bh=6NfCLWYjzohmjwKMnEJxLhyvdS+DcJjcJ204KGwB6cM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=JxC0+PgQbFLyu5BN4cHStsTyVZgdXYCKoz+x4NJDXbrf/07eOHZ4FaTeqgPOJkLSN wP1yP7WVhbnjB2JCapFBmbjrrwAagiyH1BwSLg4kBoCubZj1XCRmdqZD8FT+/TYykm bNlYZ56H3KVOk6KVOZkek3MPc9LJGN+2yDCPXKUc= From: Nuno Das Neves To: linux-hyperv@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org, wei.liu@kernel.org, mhklinux@outlook.com Cc: kys@microsoft.com, haiyangz@microsoft.com, decui@microsoft.com, catalin.marinas@arm.com, will@kernel.org, tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, x86@kernel.org, hpa@zytor.com, arnd@arndb.de, jinankjain@linux.microsoft.com, muminulrussell@gmail.com, skinsburskii@linux.microsoft.com, mukeshrathor@microsoft.com Subject: [PATCH v2 1/2] hyperv: Move hv_current_partition_id to arch-generic code Date: Wed, 22 Jan 2025 17:47:30 -0800 Message-Id: <1737596851-29555-2-git-send-email-nunodasneves@linux.microsoft.com> X-Mailer: git-send-email 1.8.3.1 In-Reply-To: <1737596851-29555-1-git-send-email-nunodasneves@linux.microsoft.com> References: <1737596851-29555-1-git-send-email-nunodasneves@linux.microsoft.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250122_174739_031673_15D94765 X-CRM114-Status: GOOD ( 18.33 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org From: Nuno Das Neves Move hv_current_partition_id and hv_get_partition_id() to hv_common.c. These aren't specific to x86_64 and will be needed by common code. Set hv_current_partition_id to HV_PARTITION_ID_SELF by default. Use a stack variable for the output of the hypercall. This allows moving the call of hv_get_partition_id() to hv_common_init() before the percpu pages are initialized. Remove the BUG()s. Failing to get the id need not crash the machine. Signed-off-by: Nuno Das Neves --- arch/x86/hyperv/hv_init.c | 26 -------------------------- arch/x86/include/asm/mshyperv.h | 2 -- drivers/hv/hv_common.c | 23 +++++++++++++++++++++++ include/asm-generic/mshyperv.h | 1 + 4 files changed, 24 insertions(+), 28 deletions(-) diff --git a/arch/x86/hyperv/hv_init.c b/arch/x86/hyperv/hv_init.c index 173005e6a95d..6b9f6f9f704d 100644 --- a/arch/x86/hyperv/hv_init.c +++ b/arch/x86/hyperv/hv_init.c @@ -34,9 +34,6 @@ #include #include -u64 hv_current_partition_id = ~0ull; -EXPORT_SYMBOL_GPL(hv_current_partition_id); - void *hv_hypercall_pg; EXPORT_SYMBOL_GPL(hv_hypercall_pg); @@ -393,24 +390,6 @@ static void __init hv_stimer_setup_percpu_clockev(void) old_setup_percpu_clockev(); } -static void __init hv_get_partition_id(void) -{ - struct hv_get_partition_id *output_page; - u64 status; - unsigned long flags; - - local_irq_save(flags); - output_page = *this_cpu_ptr(hyperv_pcpu_output_arg); - status = hv_do_hypercall(HVCALL_GET_PARTITION_ID, NULL, output_page); - if (!hv_result_success(status)) { - /* No point in proceeding if this failed */ - pr_err("Failed to get partition ID: %lld\n", status); - BUG(); - } - hv_current_partition_id = output_page->partition_id; - local_irq_restore(flags); -} - #if IS_ENABLED(CONFIG_HYPERV_VTL_MODE) static u8 __init get_vtl(void) { @@ -605,11 +584,6 @@ void __init hyperv_init(void) register_syscore_ops(&hv_syscore_ops); - if (cpuid_ebx(HYPERV_CPUID_FEATURES) & HV_ACCESS_PARTITION_ID) - hv_get_partition_id(); - - BUG_ON(hv_root_partition && hv_current_partition_id == ~0ull); - #ifdef CONFIG_PCI_MSI /* * If we're running as root, we want to create our own PCI MSI domain. diff --git a/arch/x86/include/asm/mshyperv.h b/arch/x86/include/asm/mshyperv.h index f91ab1e75f9f..8d3ada3e8d0d 100644 --- a/arch/x86/include/asm/mshyperv.h +++ b/arch/x86/include/asm/mshyperv.h @@ -43,8 +43,6 @@ extern bool hyperv_paravisor_present; extern void *hv_hypercall_pg; -extern u64 hv_current_partition_id; - extern union hv_ghcb * __percpu *hv_ghcb_pg; bool hv_isolation_type_snp(void); diff --git a/drivers/hv/hv_common.c b/drivers/hv/hv_common.c index af5d1dc451f6..1da19b64ef16 100644 --- a/drivers/hv/hv_common.c +++ b/drivers/hv/hv_common.c @@ -31,6 +31,9 @@ #include #include +u64 hv_current_partition_id = HV_PARTITION_ID_SELF; +EXPORT_SYMBOL_GPL(hv_current_partition_id); + /* * hv_root_partition, ms_hyperv and hv_nested are defined here with other * Hyper-V specific globals so they are shared across all architectures and are @@ -283,6 +286,23 @@ static inline bool hv_output_page_exists(void) return hv_root_partition || IS_ENABLED(CONFIG_HYPERV_VTL_MODE); } +static void __init hv_get_partition_id(void) +{ + /* + * Note in this case the output can be on the stack because it is just + * a single u64 and hence won't cross a page boundary. + */ + struct hv_get_partition_id output; + u64 status; + + status = hv_do_hypercall(HVCALL_GET_PARTITION_ID, NULL, &output); + if (!hv_result_success(status)) { + pr_err("Hyper-V: failed to get partition ID: %#lx\n", status); + return; + } + hv_current_partition_id = output.partition_id; +} + int __init hv_common_init(void) { int i; @@ -298,6 +318,9 @@ int __init hv_common_init(void) if (hv_is_isolation_supported()) sysctl_record_panic_msg = 0; + if (ms_hyperv.priv_high & HV_ACCESS_PARTITION_ID) + hv_get_partition_id(); + /* * Hyper-V expects to get crash register data or kmsg when * crash enlightment is available and system crashes. Set diff --git a/include/asm-generic/mshyperv.h b/include/asm-generic/mshyperv.h index a7bbe504e4f3..98100466e0b2 100644 --- a/include/asm-generic/mshyperv.h +++ b/include/asm-generic/mshyperv.h @@ -58,6 +58,7 @@ struct ms_hyperv_info { }; extern struct ms_hyperv_info ms_hyperv; extern bool hv_nested; +extern u64 hv_current_partition_id; extern void * __percpu *hyperv_pcpu_input_arg; extern void * __percpu *hyperv_pcpu_output_arg;