From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751630AbbJLGAs (ORCPT ); Mon, 12 Oct 2015 02:00:48 -0400 Received: from mail-pa0-f41.google.com ([209.85.220.41]:32995 "EHLO mail-pa0-f41.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751178AbbJLGAq (ORCPT ); Mon, 12 Oct 2015 02:00:46 -0400 Content-Type: text/plain; charset=us-ascii Mime-Version: 1.0 (Mac OS X Mail 9.0 \(3094\)) Subject: Re: [PATCH] ARM:mm: fix kmap_atomic_to_page From: yalin wang In-Reply-To: <1444129773-12632-1-git-send-email-chanho.min@lge.com> Date: Mon, 12 Oct 2015 14:00:38 +0800 Cc: Russell King , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Jongsung Kim , Gunho Lee Content-Transfer-Encoding: 7bit Message-Id: <3B252F19-0EE2-4CE3-81B5-E8BED7212A2D@gmail.com> References: <1444129773-12632-1-git-send-email-chanho.min@lge.com> To: Chanho Min X-Mailer: Apple Mail (2.3094) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > On Oct 6, 2015, at 19:09, Chanho Min wrote: > > Since kmap_atomic returns the pkmap address without a new mapping to > fixmap for the page that is already mapped by kmap, It should be > considered for the pkmap address in kmap_atomic_to_page. > > Signed-off-by: Chanho Min > --- > arch/arm/mm/highmem.c | 11 ++++++++--- > 1 file changed, 8 insertions(+), 3 deletions(-) > > diff --git a/arch/arm/mm/highmem.c b/arch/arm/mm/highmem.c > index 45aeaac..3e973b7 100644- > --- a/arch/arm/mm/highmem.c > +++ b/arch/arm/mm/highmem.c > @@ -145,8 +145,13 @@ struct page *kmap_atomic_to_page(const void *ptr) > { > unsigned long vaddr = (unsigned long)ptr; > > - if (vaddr < FIXADDR_START) > - return virt_to_page(ptr); > + if (vaddr >= PKMAP_ADDR(0) && vaddr < PKMAP_ADDR(LAST_PKMAP)) { > + int i = PKMAP_NR(vaddr); > + return pte_page(pkmap_page_table[i]); > + } > + > + if (vaddr >= FIXADDR_START) > + return pte_page(get_fixmap_pte(vaddr)); > > - return pte_page(get_fixmap_pte(vaddr)); > + return virt_to_page(ptr); > } > -- > 1.7.9.5 > why not change like this, more simple : diff --git a/arch/arm/mm/highmem.c b/arch/arm/mm/highmem.c index 9df5f09..4eeed3d 100644 --- a/arch/arm/mm/highmem.c +++ b/arch/arm/mm/highmem.c @@ -152,8 +152,7 @@ struct page *kmap_atomic_to_page(const void *ptr) { unsigned long vaddr = (unsigned long)ptr; - if (vaddr < FIXADDR_START) - return virt_to_page(ptr); - - return pte_page(get_fixmap_pte(vaddr)); + if (vaddr >= FIXADDR_START && vaddr <= FIXADDR_TOP) + return pte_page(get_fixmap_pte(vaddr)); + return kmap_to_page(ptr); } Thanks