From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757476AbbA0K5d (ORCPT ); Tue, 27 Jan 2015 05:57:33 -0500 Received: from 8bytes.org ([81.169.241.247]:54377 "EHLO theia.8bytes.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752091AbbA0K53 (ORCPT ); Tue, 27 Jan 2015 05:57:29 -0500 From: Joerg Roedel To: Gleb Natapov , Paolo Bonzini Cc: kvm@vger.kernel.org, linux-kernel@vger.kernel.org, joro@8bytes.org, jroedel@suse.de Subject: [PATCH v2] kvm: iommu: Add cond_resched to legacy device assignment code Date: Tue, 27 Jan 2015 11:57:19 +0100 Message-Id: <1422356239-18203-1-git-send-email-joro@8bytes.org> X-Mailer: git-send-email 1.9.1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Joerg Roedel When assigning devices to large memory guests (>=128GB guest memory in the failure case) the functions to create the IOMMU page-tables for the whole guest might run for a very long time. On non-preemptible kernels this might cause Soft-Lockup warnings. Fix these by adding a cond_resched() to the mapping and unmapping loops. Signed-off-by: Joerg Roedel --- arch/x86/kvm/iommu.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/arch/x86/kvm/iommu.c b/arch/x86/kvm/iommu.c index 17b73ee..7dbced3 100644 --- a/arch/x86/kvm/iommu.c +++ b/arch/x86/kvm/iommu.c @@ -138,7 +138,7 @@ int kvm_iommu_map_pages(struct kvm *kvm, struct kvm_memory_slot *slot) gfn += page_size >> PAGE_SHIFT; - + cond_resched(); } return 0; @@ -306,6 +306,8 @@ static void kvm_iommu_put_pages(struct kvm *kvm, kvm_unpin_pages(kvm, pfn, unmap_pages); gfn += unmap_pages; + + cond_resched(); } } -- 1.9.1