From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752433AbaHNFDf (ORCPT ); Thu, 14 Aug 2014 01:03:35 -0400 Received: from e23smtp07.au.ibm.com ([202.81.31.140]:49580 "EHLO e23smtp07.au.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752045AbaHNFDc (ORCPT ); Thu, 14 Aug 2014 01:03:32 -0400 From: Alexey Kardashevskiy To: linuxppc-dev@lists.ozlabs.org Cc: Alexey Kardashevskiy , Benjamin Herrenschmidt , Paul Mackerras , Alexander Graf , Gleb Natapov , Paolo Bonzini , Michael Ellerman , kvm-ppc@vger.kernel.org, kvm@vger.kernel.org, linux-kernel@vger.kernel.org, "Aneesh Kumar K.V" , Joonsoo Kim Subject: [PATCH v2] PC, KVM, CMA: Fix regression caused by wrong get_order() use Date: Thu, 14 Aug 2014 15:03:07 +1000 Message-Id: <1407992587-9164-1-git-send-email-aik@ozlabs.ru> X-Mailer: git-send-email 2.0.0 X-TM-AS-MML: disable X-Content-Scanned: Fidelis XPS MAILER x-cbid: 14081405-0260-0000-0000-000000126AAF Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org fc95ca7284bc54953165cba76c3228bd2cdb9591 claims that there is no functional change but this is not true as it calls get_order() (which takes bytes) where it should have called ilog2() and the kernel stops on VM_BUG_ON(). This replaces get_order() with order_base_2() (round-up version of ilog2). Suggested-by: Paul Mackerras Cc: Alexander Graf Cc: Aneesh Kumar K.V Cc: Joonsoo Kim Cc: Benjamin Herrenschmidt Signed-off-by: Alexey Kardashevskiy --- Changes: v2: * s/ilog2/order_base_2/ * removed cc: as I got wrong impression that v3.16 is broken --- arch/powerpc/kvm/book3s_hv_builtin.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/arch/powerpc/kvm/book3s_hv_builtin.c b/arch/powerpc/kvm/book3s_hv_builtin.c index 329d7fd..b9615ba 100644 --- a/arch/powerpc/kvm/book3s_hv_builtin.c +++ b/arch/powerpc/kvm/book3s_hv_builtin.c @@ -101,7 +101,7 @@ struct kvm_rma_info *kvm_alloc_rma() ri = kmalloc(sizeof(struct kvm_rma_info), GFP_KERNEL); if (!ri) return NULL; - page = cma_alloc(kvm_cma, kvm_rma_pages, get_order(kvm_rma_pages)); + page = cma_alloc(kvm_cma, kvm_rma_pages, order_base_2(kvm_rma_pages)); if (!page) goto err_out; atomic_set(&ri->use_count, 1); @@ -135,12 +135,12 @@ struct page *kvm_alloc_hpt(unsigned long nr_pages) { unsigned long align_pages = HPT_ALIGN_PAGES; - VM_BUG_ON(get_order(nr_pages) < KVM_CMA_CHUNK_ORDER - PAGE_SHIFT); + VM_BUG_ON(order_base_2(nr_pages) < KVM_CMA_CHUNK_ORDER - PAGE_SHIFT); /* Old CPUs require HPT aligned on a multiple of its size */ if (!cpu_has_feature(CPU_FTR_ARCH_206)) align_pages = nr_pages; - return cma_alloc(kvm_cma, nr_pages, get_order(align_pages)); + return cma_alloc(kvm_cma, nr_pages, order_base_2(align_pages)); } EXPORT_SYMBOL_GPL(kvm_alloc_hpt); -- 2.0.0