From patchwork Thu Apr 20 03:07:26 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: longli@linuxonhyperv.com X-Patchwork-Id: 85701 Return-Path: Delivered-To: ouuuleilei@gmail.com Received: by 2002:a59:b0ea:0:b0:3b6:4342:cba0 with SMTP id b10csp39479vqo; Wed, 19 Apr 2023 20:18:10 -0700 (PDT) X-Google-Smtp-Source: AKy350ZzdOAAqvYKkqyMLepyJSw4syfZnUbczpmla4W6ycV9WDyKRyfmuaxw4NF5tk89X1y5wLWz X-Received: by 2002:a05:6808:5d6:b0:38e:2155:bb90 with SMTP id d22-20020a05680805d600b0038e2155bb90mr160006oij.1.1681960690092; Wed, 19 Apr 2023 20:18:10 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1681960690; cv=none; d=google.com; s=arc-20160816; b=L7PH7Zgvb4tU0s+H0mY3lOtkkmEJn7F8zy/5MxX4FitcM0apVa3j/A2nupPPjLFaQg jEn/pbCk1Uojce5hgO250+H/KAGK8uR5uHTXOiHuHGf/bShgmrAkKw0veNpJwXtywU92 z3OdXjhSijWkp5Tnr0qJBAqYnJKM0S6ZTgOofgJ+QOul+H4yMH0QfwU6W/c0OKzuwYfj VBdXeoYYIcPegHca5oGJ62XMYkWusHy+XHB/pTyk1plCn+/WwyRdUrzFY0boFArVNmpG eb2OPPbGgLIKCWgowk0DSyl+erXFcvj7LiG/XWqnvabsI7VvB78lx0CeDYgOz0PHhDmc Pkrg== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:message-id:date:subject:cc:to:from :dkim-signature:dkim-filter; bh=stGMvVGCEz5A4DZbHdNjZe8mF41EgHKHd1yDX0aBU4U=; b=PPkzvGf+ma3ezW1qpgP0+4XkZAtGYVZQhmAKRvjVaFoiqCjl4VmIt3ZybG9WXx++4/ VWtp4DfFjeIeQfkgieMyCNX3ew40hFhTBMZyRGm6qOGwDgK14Y9/v8bBDUeAIDtviwfD O5sQUGdy1H5Iqe2VeQButcQE3v4GikDmAVZnwQCjEzNjo59/G/SLrCBuPrz0tE2WzenJ OAb07xJf5KWDKVFt04fuCiJqXo4dMhIWj/bF81jd7/kIsdIYV10ffyIJdXCNI8Kt8C9b uyGpuLfDfbmeNHWFOWNAODlsUW3CzuWsp3wpGI5iDP14hWQq67G61j/GYp+CjXD18xsd DeSQ== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@linuxonhyperv.com header.s=default header.b=GJAMk5Xn; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=linuxonhyperv.com Received: from out1.vger.email (out1.vger.email. [2620:137:e000::1:20]) by mx.google.com with ESMTP id bg40-20020a05680817a800b0038e4ca6ecf8si615210oib.47.2023.04.19.20.17.56; Wed, 19 Apr 2023 20:18:10 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20; Authentication-Results: mx.google.com; dkim=pass header.i=@linuxonhyperv.com header.s=default header.b=GJAMk5Xn; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=linuxonhyperv.com Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232730AbjDTDIL (ORCPT + 99 others); Wed, 19 Apr 2023 23:08:11 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56440 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233788AbjDTDHe (ORCPT ); Wed, 19 Apr 2023 23:07:34 -0400 Received: from linux.microsoft.com (linux.microsoft.com [13.77.154.182]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 9465C4C20; Wed, 19 Apr 2023 20:07:31 -0700 (PDT) Received: by linux.microsoft.com (Postfix, from userid 1004) id 2073F21C205D; Wed, 19 Apr 2023 20:07:31 -0700 (PDT) DKIM-Filter: OpenDKIM Filter v2.11.0 linux.microsoft.com 2073F21C205D DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxonhyperv.com; s=default; t=1681960051; bh=stGMvVGCEz5A4DZbHdNjZe8mF41EgHKHd1yDX0aBU4U=; h=From:To:Cc:Subject:Date:From; b=GJAMk5XnQsRcFXD+rXxWNAzq91dTVtLOqEAXOnB8/iFBvry+7zpV4i+FfvXSDoPw1 owakasHPYt1HKMYk08PENS4Pwxm8mpcIU+Ke4EFsECDsNlHUooFlDvNC1IqT4nbx5z PEjthae31Opfp/jTNUkfoKfI1nNFYzUtVsgBv3LI= From: longli@linuxonhyperv.com To: "K. Y. Srinivasan" , Haiyang Zhang , Wei Liu , Dexuan Cui , Arnd Bergmann Cc: linux-hyperv@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org, Long Li Subject: [PATCH v3] Drivers: hv: move panic report code from vmbus to hv early init code Date: Wed, 19 Apr 2023 20:07:26 -0700 Message-Id: <1681960046-9502-1-git-send-email-longli@linuxonhyperv.com> X-Mailer: git-send-email 1.8.3.1 X-Spam-Status: No, score=-11.6 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, RCVD_IN_DNSWL_MED,SPF_HELO_PASS,SPF_PASS,T_SCC_BODY_TEXT_LINE, USER_IN_DEF_SPF_WL autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org X-getmail-retrieved-from-mailbox: =?utf-8?q?INBOX?= X-GMAIL-THRID: =?utf-8?q?1763663612126206947?= X-GMAIL-MSGID: =?utf-8?q?1763663612126206947?= From: Long Li The panic reporting code was added in commit 81b18bce48af ("Drivers: HV: Send one page worth of kmsg dump over Hyper-V during panic") It was added to the vmbus driver. The panic reporting has no dependence on vmbus, and can be enabled at an earlier boot time when Hyper-V is initialized. This patch moves the panic reporting code out of vmbus. There is no functionality changes. During moving, also refactored some cleanup functions into hv_kmsg_dump_unregister(). Signed-off-by: Long Li Reviewed-by: Michael Kelley --- Change log v3: 1. Rebase to latest upstream code Change log v2: 1. Check on hv_is_isolation_supported() before reporting crash dump 2. Remove hyperv_report_reg(), inline the check condition instead 3. Remove the test NULL on hv_panic_page when freeing it drivers/hv/hv.c | 36 ------- drivers/hv/hv_common.c | 231 +++++++++++++++++++++++++++++++++++++++++ drivers/hv/vmbus_drv.c | 190 --------------------------------- 3 files changed, 231 insertions(+), 226 deletions(-) diff --git a/drivers/hv/hv.c b/drivers/hv/hv.c index 4e1407d59ba0..de6708dbe0df 100644 --- a/drivers/hv/hv.c +++ b/drivers/hv/hv.c @@ -38,42 +38,6 @@ int hv_init(void) return 0; } -/* - * Functions for allocating and freeing memory with size and - * alignment HV_HYP_PAGE_SIZE. These functions are needed because - * the guest page size may not be the same as the Hyper-V page - * size. We depend upon kmalloc() aligning power-of-two size - * allocations to the allocation size boundary, so that the - * allocated memory appears to Hyper-V as a page of the size - * it expects. - */ - -void *hv_alloc_hyperv_page(void) -{ - BUILD_BUG_ON(PAGE_SIZE < HV_HYP_PAGE_SIZE); - - if (PAGE_SIZE == HV_HYP_PAGE_SIZE) - return (void *)__get_free_page(GFP_KERNEL); - else - return kmalloc(HV_HYP_PAGE_SIZE, GFP_KERNEL); -} - -void *hv_alloc_hyperv_zeroed_page(void) -{ - if (PAGE_SIZE == HV_HYP_PAGE_SIZE) - return (void *)__get_free_page(GFP_KERNEL | __GFP_ZERO); - else - return kzalloc(HV_HYP_PAGE_SIZE, GFP_KERNEL); -} - -void hv_free_hyperv_page(unsigned long addr) -{ - if (PAGE_SIZE == HV_HYP_PAGE_SIZE) - free_page(addr); - else - kfree((void *)addr); -} - /* * hv_post_message - Post a message using the hypervisor message IPC. * diff --git a/drivers/hv/hv_common.c b/drivers/hv/hv_common.c index 6d40b6c7b23b..64f9ceca887b 100644 --- a/drivers/hv/hv_common.c +++ b/drivers/hv/hv_common.c @@ -17,8 +17,11 @@ #include #include #include +#include #include #include +#include +#include #include #include #include @@ -54,6 +57,10 @@ EXPORT_SYMBOL_GPL(hyperv_pcpu_input_arg); void * __percpu *hyperv_pcpu_output_arg; EXPORT_SYMBOL_GPL(hyperv_pcpu_output_arg); +static void hv_kmsg_dump_unregister(void); + +static struct ctl_table_header *hv_ctl_table_hdr; + /* * Hyper-V specific initialization and shutdown code that is * common across all architectures. Called from architecture @@ -62,6 +69,12 @@ EXPORT_SYMBOL_GPL(hyperv_pcpu_output_arg); void __init hv_common_free(void) { + unregister_sysctl_table(hv_ctl_table_hdr); + hv_ctl_table_hdr = NULL; + + if (ms_hyperv.misc_features & HV_FEATURE_GUEST_CRASH_MSR_AVAILABLE) + hv_kmsg_dump_unregister(); + kfree(hv_vp_index); hv_vp_index = NULL; @@ -72,10 +85,203 @@ void __init hv_common_free(void) hyperv_pcpu_input_arg = NULL; } +/* + * Functions for allocating and freeing memory with size and + * alignment HV_HYP_PAGE_SIZE. These functions are needed because + * the guest page size may not be the same as the Hyper-V page + * size. We depend upon kmalloc() aligning power-of-two size + * allocations to the allocation size boundary, so that the + * allocated memory appears to Hyper-V as a page of the size + * it expects. + */ + +void *hv_alloc_hyperv_page(void) +{ + BUILD_BUG_ON(PAGE_SIZE < HV_HYP_PAGE_SIZE); + + if (PAGE_SIZE == HV_HYP_PAGE_SIZE) + return (void *)__get_free_page(GFP_KERNEL); + else + return kmalloc(HV_HYP_PAGE_SIZE, GFP_KERNEL); +} +EXPORT_SYMBOL_GPL(hv_alloc_hyperv_page); + +void *hv_alloc_hyperv_zeroed_page(void) +{ + if (PAGE_SIZE == HV_HYP_PAGE_SIZE) + return (void *)__get_free_page(GFP_KERNEL | __GFP_ZERO); + else + return kzalloc(HV_HYP_PAGE_SIZE, GFP_KERNEL); +} +EXPORT_SYMBOL_GPL(hv_alloc_hyperv_zeroed_page); + +void hv_free_hyperv_page(unsigned long addr) +{ + if (PAGE_SIZE == HV_HYP_PAGE_SIZE) + free_page(addr); + else + kfree((void *)addr); +} +EXPORT_SYMBOL_GPL(hv_free_hyperv_page); + +static void *hv_panic_page; + +/* + * Boolean to control whether to report panic messages over Hyper-V. + * + * It can be set via /proc/sys/kernel/hyperv_record_panic_msg + */ +static int sysctl_record_panic_msg = 1; + +/* + * sysctl option to allow the user to control whether kmsg data should be + * reported to Hyper-V on panic. + */ +static struct ctl_table hv_ctl_table[] = { + { + .procname = "hyperv_record_panic_msg", + .data = &sysctl_record_panic_msg, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = proc_dointvec_minmax, + .extra1 = SYSCTL_ZERO, + .extra2 = SYSCTL_ONE + }, + {} +}; + +static int hv_die_panic_notify_crash(struct notifier_block *self, + unsigned long val, void *args); + +static struct notifier_block hyperv_die_report_block = { + .notifier_call = hv_die_panic_notify_crash, +}; + +static struct notifier_block hyperv_panic_report_block = { + .notifier_call = hv_die_panic_notify_crash, +}; + +/* + * The following callback works both as die and panic notifier; its + * goal is to provide panic information to the hypervisor unless the + * kmsg dumper is used [see hv_kmsg_dump()], which provides more + * information but isn't always available. + * + * Notice that both the panic/die report notifiers are registered only + * if we have the capability HV_FEATURE_GUEST_CRASH_MSR_AVAILABLE set. + */ +static int hv_die_panic_notify_crash(struct notifier_block *self, + unsigned long val, void *args) +{ + struct pt_regs *regs; + bool is_die; + + /* Don't notify Hyper-V unless we have a die oops event or panic. */ + if (self == &hyperv_panic_report_block) { + is_die = false; + regs = current_pt_regs(); + } else { /* die event */ + if (val != DIE_OOPS) + return NOTIFY_DONE; + + is_die = true; + regs = ((struct die_args *)args)->regs; + } + + /* + * Hyper-V should be notified only once about a panic/die. If we will + * be calling hv_kmsg_dump() later with kmsg data, don't do the + * notification here. + */ + if (!sysctl_record_panic_msg || !hv_panic_page) + hyperv_report_panic(regs, val, is_die); + + return NOTIFY_DONE; +} + +/* + * Callback from kmsg_dump. Grab as much as possible from the end of the kmsg + * buffer and call into Hyper-V to transfer the data. + */ +static void hv_kmsg_dump(struct kmsg_dumper *dumper, + enum kmsg_dump_reason reason) +{ + struct kmsg_dump_iter iter; + size_t bytes_written; + + /* We are only interested in panics. */ + if (reason != KMSG_DUMP_PANIC || !sysctl_record_panic_msg) + return; + + /* + * Write dump contents to the page. No need to synchronize; panic should + * be single-threaded. + */ + kmsg_dump_rewind(&iter); + kmsg_dump_get_buffer(&iter, false, hv_panic_page, HV_HYP_PAGE_SIZE, + &bytes_written); + if (!bytes_written) + return; + /* + * P3 to contain the physical address of the panic page & P4 to + * contain the size of the panic data in that page. Rest of the + * registers are no-op when the NOTIFY_MSG flag is set. + */ + hv_set_register(HV_REGISTER_CRASH_P0, 0); + hv_set_register(HV_REGISTER_CRASH_P1, 0); + hv_set_register(HV_REGISTER_CRASH_P2, 0); + hv_set_register(HV_REGISTER_CRASH_P3, virt_to_phys(hv_panic_page)); + hv_set_register(HV_REGISTER_CRASH_P4, bytes_written); + + /* + * Let Hyper-V know there is crash data available along with + * the panic message. + */ + hv_set_register(HV_REGISTER_CRASH_CTL, + (HV_CRASH_CTL_CRASH_NOTIFY | + HV_CRASH_CTL_CRASH_NOTIFY_MSG)); +} + +static struct kmsg_dumper hv_kmsg_dumper = { + .dump = hv_kmsg_dump, +}; + +static void hv_kmsg_dump_unregister(void) +{ + kmsg_dump_unregister(&hv_kmsg_dumper); + unregister_die_notifier(&hyperv_die_report_block); + atomic_notifier_chain_unregister(&panic_notifier_list, + &hyperv_panic_report_block); + + hv_free_hyperv_page((unsigned long)hv_panic_page); + hv_panic_page = NULL; +} + +static void hv_kmsg_dump_register(void) +{ + int ret; + + hv_panic_page = hv_alloc_hyperv_zeroed_page(); + if (!hv_panic_page) { + pr_err("Hyper-V: panic message page memory allocation failed\n"); + return; + } + + ret = kmsg_dump_register(&hv_kmsg_dumper); + if (ret) { + pr_err("Hyper-V: kmsg dump register error 0x%x\n", ret); + hv_free_hyperv_page((unsigned long)hv_panic_page); + hv_panic_page = NULL; + } +} + int __init hv_common_init(void) { int i; + if (hv_is_isolation_supported()) + sysctl_record_panic_msg = 0; + /* * Hyper-V expects to get crash register data or kmsg when * crash enlightment is available and system crashes. Set @@ -84,8 +290,33 @@ int __init hv_common_init(void) * kernel. */ if (ms_hyperv.misc_features & HV_FEATURE_GUEST_CRASH_MSR_AVAILABLE) { + u64 hyperv_crash_ctl; + crash_kexec_post_notifiers = true; pr_info("Hyper-V: enabling crash_kexec_post_notifiers\n"); + + /* + * Panic message recording (sysctl_record_panic_msg) + * is enabled by default in non-isolated guests and + * disabled by default in isolated guests; the panic + * message recording won't be available in isolated + * guests should the following registration fail. + */ + hv_ctl_table_hdr = register_sysctl("kernel", hv_ctl_table); + if (!hv_ctl_table_hdr) + pr_err("Hyper-V: sysctl table register error"); + + /* + * Register for panic kmsg callback only if the right + * capability is supported by the hypervisor. + */ + hyperv_crash_ctl = hv_get_register(HV_REGISTER_CRASH_CTL); + if (hyperv_crash_ctl & HV_CRASH_CTL_CRASH_NOTIFY_MSG) + hv_kmsg_dump_register(); + + register_die_notifier(&hyperv_die_report_block); + atomic_notifier_chain_register(&panic_notifier_list, + &hyperv_panic_report_block); } /* diff --git a/drivers/hv/vmbus_drv.c b/drivers/hv/vmbus_drv.c index 9a63a0d9f596..1c65a6dfb9fa 100644 --- a/drivers/hv/vmbus_drv.c +++ b/drivers/hv/vmbus_drv.c @@ -30,7 +30,6 @@ #include #include #include -#include #include #include #include @@ -50,26 +49,12 @@ static struct device *hv_dev; static int hyperv_cpuhp_online; -static void *hv_panic_page; - static long __percpu *vmbus_evt; /* Values parsed from ACPI DSDT */ int vmbus_irq; int vmbus_interrupt; -/* - * Boolean to control whether to report panic messages over Hyper-V. - * - * It can be set via /proc/sys/kernel/hyperv_record_panic_msg - */ -static int sysctl_record_panic_msg = 1; - -static int hyperv_report_reg(void) -{ - return !sysctl_record_panic_msg || !hv_panic_page; -} - /* * The panic notifier below is responsible solely for unloading the * vmbus connection, which is necessary in a panic event. @@ -90,54 +75,6 @@ static struct notifier_block hyperv_panic_vmbus_unload_block = { .priority = INT_MIN + 1, /* almost the latest one to execute */ }; -static int hv_die_panic_notify_crash(struct notifier_block *self, - unsigned long val, void *args); - -static struct notifier_block hyperv_die_report_block = { - .notifier_call = hv_die_panic_notify_crash, -}; -static struct notifier_block hyperv_panic_report_block = { - .notifier_call = hv_die_panic_notify_crash, -}; - -/* - * The following callback works both as die and panic notifier; its - * goal is to provide panic information to the hypervisor unless the - * kmsg dumper is used [see hv_kmsg_dump()], which provides more - * information but isn't always available. - * - * Notice that both the panic/die report notifiers are registered only - * if we have the capability HV_FEATURE_GUEST_CRASH_MSR_AVAILABLE set. - */ -static int hv_die_panic_notify_crash(struct notifier_block *self, - unsigned long val, void *args) -{ - struct pt_regs *regs; - bool is_die; - - /* Don't notify Hyper-V unless we have a die oops event or panic. */ - if (self == &hyperv_panic_report_block) { - is_die = false; - regs = current_pt_regs(); - } else { /* die event */ - if (val != DIE_OOPS) - return NOTIFY_DONE; - - is_die = true; - regs = ((struct die_args *)args)->regs; - } - - /* - * Hyper-V should be notified only once about a panic/die. If we will - * be calling hv_kmsg_dump() later with kmsg data, don't do the - * notification here. - */ - if (hyperv_report_reg()) - hyperv_report_panic(regs, val, is_die); - - return NOTIFY_DONE; -} - static const char *fb_mmio_name = "fb_range"; static struct resource *fb_mmio; static struct resource *hyperv_mmio; @@ -1379,89 +1316,6 @@ static irqreturn_t vmbus_percpu_isr(int irq, void *dev_id) return IRQ_HANDLED; } -/* - * Callback from kmsg_dump. Grab as much as possible from the end of the kmsg - * buffer and call into Hyper-V to transfer the data. - */ -static void hv_kmsg_dump(struct kmsg_dumper *dumper, - enum kmsg_dump_reason reason) -{ - struct kmsg_dump_iter iter; - size_t bytes_written; - - /* We are only interested in panics. */ - if ((reason != KMSG_DUMP_PANIC) || (!sysctl_record_panic_msg)) - return; - - /* - * Write dump contents to the page. No need to synchronize; panic should - * be single-threaded. - */ - kmsg_dump_rewind(&iter); - kmsg_dump_get_buffer(&iter, false, hv_panic_page, HV_HYP_PAGE_SIZE, - &bytes_written); - if (!bytes_written) - return; - /* - * P3 to contain the physical address of the panic page & P4 to - * contain the size of the panic data in that page. Rest of the - * registers are no-op when the NOTIFY_MSG flag is set. - */ - hv_set_register(HV_REGISTER_CRASH_P0, 0); - hv_set_register(HV_REGISTER_CRASH_P1, 0); - hv_set_register(HV_REGISTER_CRASH_P2, 0); - hv_set_register(HV_REGISTER_CRASH_P3, virt_to_phys(hv_panic_page)); - hv_set_register(HV_REGISTER_CRASH_P4, bytes_written); - - /* - * Let Hyper-V know there is crash data available along with - * the panic message. - */ - hv_set_register(HV_REGISTER_CRASH_CTL, - (HV_CRASH_CTL_CRASH_NOTIFY | HV_CRASH_CTL_CRASH_NOTIFY_MSG)); -} - -static struct kmsg_dumper hv_kmsg_dumper = { - .dump = hv_kmsg_dump, -}; - -static void hv_kmsg_dump_register(void) -{ - int ret; - - hv_panic_page = hv_alloc_hyperv_zeroed_page(); - if (!hv_panic_page) { - pr_err("Hyper-V: panic message page memory allocation failed\n"); - return; - } - - ret = kmsg_dump_register(&hv_kmsg_dumper); - if (ret) { - pr_err("Hyper-V: kmsg dump register error 0x%x\n", ret); - hv_free_hyperv_page((unsigned long)hv_panic_page); - hv_panic_page = NULL; - } -} - -static struct ctl_table_header *hv_ctl_table_hdr; - -/* - * sysctl option to allow the user to control whether kmsg data should be - * reported to Hyper-V on panic. - */ -static struct ctl_table hv_ctl_table[] = { - { - .procname = "hyperv_record_panic_msg", - .data = &sysctl_record_panic_msg, - .maxlen = sizeof(int), - .mode = 0644, - .proc_handler = proc_dointvec_minmax, - .extra1 = SYSCTL_ZERO, - .extra2 = SYSCTL_ONE - }, - {} -}; - /* * vmbus_bus_init -Main vmbus driver initialization routine. * @@ -1525,38 +1379,6 @@ static int vmbus_bus_init(void) if (ret) goto err_connect; - if (hv_is_isolation_supported()) - sysctl_record_panic_msg = 0; - - /* - * Only register if the crash MSRs are available - */ - if (ms_hyperv.misc_features & HV_FEATURE_GUEST_CRASH_MSR_AVAILABLE) { - u64 hyperv_crash_ctl; - /* - * Panic message recording (sysctl_record_panic_msg) - * is enabled by default in non-isolated guests and - * disabled by default in isolated guests; the panic - * message recording won't be available in isolated - * guests should the following registration fail. - */ - hv_ctl_table_hdr = register_sysctl("kernel", hv_ctl_table); - if (!hv_ctl_table_hdr) - pr_err("Hyper-V: sysctl table register error"); - - /* - * Register for panic kmsg callback only if the right - * capability is supported by the hypervisor. - */ - hyperv_crash_ctl = hv_get_register(HV_REGISTER_CRASH_CTL); - if (hyperv_crash_ctl & HV_CRASH_CTL_CRASH_NOTIFY_MSG) - hv_kmsg_dump_register(); - - register_die_notifier(&hyperv_die_report_block); - atomic_notifier_chain_register(&panic_notifier_list, - &hyperv_panic_report_block); - } - /* * Always register the vmbus unload panic notifier because we * need to shut the VMbus channel connection on panic. @@ -1581,8 +1403,6 @@ static int vmbus_bus_init(void) } err_setup: bus_unregister(&hv_bus); - unregister_sysctl_table(hv_ctl_table_hdr); - hv_ctl_table_hdr = NULL; return ret; } @@ -2878,13 +2698,6 @@ static void __exit vmbus_exit(void) vmbus_free_channels(); kfree(vmbus_connection.channels); - if (ms_hyperv.misc_features & HV_FEATURE_GUEST_CRASH_MSR_AVAILABLE) { - kmsg_dump_unregister(&hv_kmsg_dumper); - unregister_die_notifier(&hyperv_die_report_block); - atomic_notifier_chain_unregister(&panic_notifier_list, - &hyperv_panic_report_block); - } - /* * The vmbus panic notifier is always registered, hence we should * also unconditionally unregister it here as well. @@ -2892,9 +2705,6 @@ static void __exit vmbus_exit(void) atomic_notifier_chain_unregister(&panic_notifier_list, &hyperv_panic_vmbus_unload_block); - free_page((unsigned long)hv_panic_page); - unregister_sysctl_table(hv_ctl_table_hdr); - hv_ctl_table_hdr = NULL; bus_unregister(&hv_bus); cpuhp_remove_state(hyperv_cpuhp_online);