From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753417Ab0IBCmR (ORCPT ); Wed, 1 Sep 2010 22:42:17 -0400 Received: from fgwmail7.fujitsu.co.jp ([192.51.44.37]:50499 "EHLO fgwmail7.fujitsu.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752297Ab0IBCmP (ORCPT ); Wed, 1 Sep 2010 22:42:15 -0400 X-SecurityPolicyCheck: OK by SHieldMailChecker v1.5.1 Message-ID: <4C7F0F2D.3060204@np.css.fujitsu.com> Date: Thu, 02 Sep 2010 11:42:53 +0900 From: Jin Dongming User-Agent: Mozilla/5.0 (Windows; U; Windows NT 6.1; ja; rv:1.9.2.7) Gecko/20100713 Thunderbird/3.1.1 MIME-Version: 1.0 To: APEI-lenb CC: Huang Ying , Andi Kleen , ACPI , LKLM , Randy Dunlap , Stephen Rothwell , Hidetoshi Seto Subject: Re: [PATCH 1/2] [Patch-next -v2] ACPI, APEI Fix the return value(==NULL) of acpi_pre_map(). References: <4C7F0C79.3060506@np.css.fujitsu.com> In-Reply-To: <4C7F0C79.3060506@np.css.fujitsu.com> Content-Type: text/plain; charset=ISO-2022-JP Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, All, I am very sorry for my miss. Please cancel these two patches. I will send the new patches. Best Regards, Jin Dongming. (2010/09/02 11:31), Jin Dongming wrote: > acpi_pre_map() is used for remapping the physical address of I/O, so > it should be return NULL or remapped virtual address. The problem is > that when (paddr - pg_off) equals 0, no matter whether I/O remapping is > successful or not, the function returns NULL. > > In acpi_pre_map(), after the physical address is remapped sucessfully, > it will check whether the physical address has been added into acpi_iomaps > list again. > - If the physical address has beed added into acpi_iomaps, the virtual > address will be saved in vaddr. > - Otherwise, NULL be saved in vaddr. > > So if the physical address is the first time to be remapped, vaddr will be > NULL always. > > In many cases, (paddr - pg_off) may not equal 0. So the function could work > well. In our machine, (paddr - pg_off) equals 0, so the return value of > acpi_pre_map() is NULL. > > This patch fixed it and I confirmed it on x86_64 next-tree. > > Signed-off-by: Jin Dongming > --- > drivers/acpi/atomicio.c | 4 ++-- > 1 files changed, 2 insertions(+), 2 deletions(-) > > diff --git a/drivers/acpi/atomicio.c b/drivers/acpi/atomicio.c > index 8f8bd73..1bc2614 100644 > --- a/drivers/acpi/atomicio.c > +++ b/drivers/acpi/atomicio.c > @@ -133,7 +133,7 @@ static void __iomem *acpi_pre_map(phys_addr_t paddr, > > spin_lock_irqsave(&acpi_iomaps_lock, flags); > vaddr = __acpi_try_ioremap(paddr, size); > - if (vaddr) { > + if (unlikely(vaddr)) { > spin_unlock_irqrestore(&acpi_iomaps_lock, flags); > iounmap(map->vaddr); > kfree(map); > @@ -142,7 +142,7 @@ static void __iomem *acpi_pre_map(phys_addr_t paddr, > list_add_tail_rcu(&map->list, &acpi_iomaps); > spin_unlock_irqrestore(&acpi_iomaps_lock, flags); > > - return vaddr + (paddr - pg_off); > + return map->vaddr + (paddr - pg_off); > err_unmap: > iounmap(vaddr); > return NULL; > -- 1.7.1.1 > > -- > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > Please read the FAQ at http://www.tux.org/lkml/ > >