From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932138AbbDMK42 (ORCPT ); Mon, 13 Apr 2015 06:56:28 -0400 Received: from mx1.redhat.com ([209.132.183.28]:59930 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753978AbbDMK4T (ORCPT ); Mon, 13 Apr 2015 06:56:19 -0400 From: Vitaly Kuznetsov To: "K. Y. Srinivasan" Cc: Haiyang Zhang , devel@linuxdriverproject.org, linux-kernel@vger.kernel.org, Dexuan Cui , Jake Oshins , Nick Meier Subject: [PATCH 2/2] Drivers: hv: vmbus: unregister panic notifier on module unload Date: Mon, 13 Apr 2015 12:56:07 +0200 Message-Id: <1428922567-11225-3-git-send-email-vkuznets@redhat.com> In-Reply-To: <1428922567-11225-1-git-send-email-vkuznets@redhat.com> References: <1428922567-11225-1-git-send-email-vkuznets@redhat.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit 96c1d0581d00f7abe033350edb021a9d947d8d81 ("Drivers: hv: vmbus: Add support for VMBus panic notifier handler") introduced atomic_notifier_chain_register() call on module load. We also need to call atomic_notifier_chain_unregister() on module unload as otherwise the following crash is observed when we bring hv_vmbus back: [ 39.788877] BUG: unable to handle kernel paging request at ffffffffa00078a8 [ 39.788877] IP: [] notifier_call_chain+0x3f/0x80 ... [ 39.788877] Call Trace: [ 39.788877] [] __atomic_notifier_call_chain+0x5d/0x90 ... [ 39.788877] [] ? atomic_notifier_chain_register+0x38/0x70 [ 39.788877] [] ? atomic_notifier_chain_register+0x17/0x70 [ 39.788877] [] hv_acpi_init+0x14f/0x1000 [hv_vmbus] [ 39.788877] [] do_one_initcall+0xd4/0x210 ... [ 39.788877] RIP [] notifier_call_chain+0x3f/0x80 Signed-off-by: Vitaly Kuznetsov --- drivers/hv/vmbus_drv.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/hv/vmbus_drv.c b/drivers/hv/vmbus_drv.c index 0d8d1d7..7870a90 100644 --- a/drivers/hv/vmbus_drv.c +++ b/drivers/hv/vmbus_drv.c @@ -1108,6 +1108,10 @@ static void __exit vmbus_exit(void) hv_synic_clockevents_cleanup(); hv_remove_vmbus_irq(); vmbus_free_channels(); + if (ms_hyperv.features & HV_FEATURE_GUEST_CRASH_MSR_AVAILABLE) { + atomic_notifier_chain_unregister(&panic_notifier_list, + &hyperv_panic_block); + } bus_unregister(&hv_bus); hv_cleanup(); for_each_online_cpu(cpu) -- 1.9.3