Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
Subject: Re: [PATCH v2] dma-mapping: use vmalloc_to_page for vmalloc addresses
To:     Roman Skakun <rm.skakun@gmail.com>,
        Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc:     Juergen Gross <jgross@suse.com>,
        Stefano Stabellini <sstabellini@kernel.org>,
        xen-devel@lists.xenproject.org, iommu@lists.linux-foundation.org,
        linux-kernel@vger.kernel.org,
        Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com>,
        Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>,
        Volodymyr Babchuk <volodymyr_babchuk@epam.com>,
        Roman Skakun <roman_skakun@epam.com>,
        Andrii Anisov <andrii_anisov@epam.com>,
        Christoph Hellwig <hch@lst.de>
References: <20210616154436.GA7619@lst.de>
 <20210622133414.132754-1-rm.skakun@gmail.com> <YO4si0to/XYximwM@fedora>
 <CADu_u-OMx6Pj4DQDoOsdh6aNAzYys-+R=o+OzHYtLm=nECgkyQ@mail.gmail.com>
From:   Boris Ostrovsky <boris.ostrovsky@oracle.com>
Message-ID: <fb262a14-a69c-030b-1f39-d924553ddbd2@oracle.com>
Date:   Thu, 15 Jul 2021 12:58:53 -0400
User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:78.0)
 Gecko/20100101 Thunderbird/78.11.0
In-Reply-To: <CADu_u-OMx6Pj4DQDoOsdh6aNAzYys-+R=o+OzHYtLm=nECgkyQ@mail.gmail.com>
Content-Type: text/plain; charset=utf-8
Content-Transfer-Encoding: 8bit
Content-Language: en-US
MIME-Version: 1.0
X-MS-Exchange-MessageSentRepresentingType: 1
Received: from [10.74.100.129] (138.3.201.1) by SN4PR0501CA0033.namprd05.prod.outlook.com (2603:10b6:803:40::46) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.4352.9 via Frontend Transport; Thu, 15 Jul 2021 16:58:56 +0000
X-MS-PublicTrafficType: Email
X-MS-Office365-Filtering-Correlation-Id: e0c6d445-d103-424f-cd70-08d947b1d6cd
X-MS-TrafficTypeDiagnostic: MN2PR10MB4029:
X-MS-Exchange-Transport-Forked: True
X-Microsoft-Antispam-PRVS: <MN2PR10MB402910554450C444A6F24A6B8A129@MN2PR10MB4029.namprd10.prod.outlook.com>
X-MS-Oob-TLC-OOBClassifiers: OLM:854;
X-MS-Exchange-SenderADCheck: 1
X-MS-Exchange-AntiSpam-Relay: 0
X-Microsoft-Antispam: BCL:0;
X-Microsoft-Antispam-Message-Info: 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
X-Forefront-Antispam-Report: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:BLAPR10MB5009.namprd10.prod.outlook.com;PTR:;CAT:NONE;SFS:(346002)(376002)(396003)(39860400002)(136003)(366004)(86362001)(83380400001)(31696002)(4326008)(26005)(53546011)(66556008)(66476007)(478600001)(186003)(5660300002)(110136005)(54906003)(66946007)(31686004)(16576012)(2616005)(956004)(8676002)(316002)(44832011)(38100700002)(7416002)(6636002)(36756003)(2906002)(6666004)(6486002)(8936002)(43740500002)(45980500001);DIR:OUT;SFP:1101;
X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1
X-MS-Exchange-AntiSpam-MessageData-0: =?utf-8?B?WWg1eVBBQ0g0K1BRclgzMHg4UWxpa3Fzc3VoTHYvTGljWWU1bVhPNGxMeVd0?=
 =?utf-8?B?Wmt6OGZDckM3MXZOdzJuNHp4ZGpHTENVdEpJQzhBRDR5a3BzZUFiU000czdH?=
 =?utf-8?B?V3B5NzlEaHlUVmcwUWZvSHhXd2IyOCsvZjBwT25OaEFKYUYvRFZMY0laNHdU?=
 =?utf-8?B?SDV1ZndJcGpTU3ZkWlhJQzJJalJQTWFSMXNyT0tXbEhGbHpGaDUzb1ZtdUVs?=
 =?utf-8?B?SjNqV3drZXdwRGxTZ2M2NlNhRkJpanM0VUNIeURzb1diM3lCS2tkU1l0cXI5?=
 =?utf-8?B?UDFzUmdtb29pT2o3RytpalllVEd0OGVKVDF4L01ZUXNqL2V5WUg0bDhEU0pr?=
 =?utf-8?B?bXIxZGM4ZGh2Zkt1bHNaTEJyUkh1Ky9QTlR2VTE3RDhXNytraWZuRnBMU01O?=
 =?utf-8?B?a2hRS3hlazArTjNvYTljMXZWMmFYMG1PVi9RWjA4Q3NUVEMxb2JnbXRidFVZ?=
 =?utf-8?B?eXNseUxHaXJhanl3Wk5MNkJpbzBLQ3hsRGdLbldOOE9TbktvVGJaZE55VEZD?=
 =?utf-8?B?a1VYSTlmbGtyWnRjeFVNb1Q2dSthYjFmMmZMeGVqSkhUZHh0T0Z3dDdKVC9D?=
 =?utf-8?B?NlN5d3NsaTlnV3JmNWhBRy9xQytnY3JoUGVGandqNDlraE1WNWFESmxWYXJW?=
 =?utf-8?B?RjJLVXlJcVdVcGZzRFpIN1pWVFhwdjhwU09MVEQvKzlKSzNiZWFMcmtlZTIw?=
 =?utf-8?B?L3d6WTFkU0ZTc2F6NzQwY3M4RGFVRGhpc3JSZC9uc29jWVMxNXlFNzZJMkYr?=
 =?utf-8?B?VDlpNHk2TGI2L096N0NNZ29qcy8vVVZQUU5sNmVpbmN4WHQwMUpZRHdaeEd2?=
 =?utf-8?B?ZnBwbGd4VDhZamJ4d3RIQW4zMEgwUkFPQU96cEpZR0RsWVVNMlBBTVpVbm9t?=
 =?utf-8?B?ZVJrT0NNZjJxTk55MlI3QnU5N3hmRDRwVC9kdVZFLzBJbG1sb1U3eDNlZ0tL?=
 =?utf-8?B?bnZMUVhpdCs0dkllYjhiZTM4Vk5uTURkV3VmZzZ4SFptUDlSVlJUS1haSkFi?=
 =?utf-8?B?NDZ5WlF6ajg5b3MrUU9STVVRbmRaT25od1ZKQjBROTV4cndsZm13TnVxdlZN?=
 =?utf-8?B?a2FDWDM5VldYeUtaV3FLMVE5SkZkd1FxTXl3VXJ4bVpZTm53RmhWVGJUd3Fw?=
 =?utf-8?B?N2dOalI1WjZwaElpTEVnUVFGeTk1NlhVS0hVdldwMWtCUmhzTFphU29ITnNT?=
 =?utf-8?B?YnBGTTh1REpwU2VkTXJ4RVh6c2piMGJldWpKZlpMdldiUlNqOGl0b0U0a2xv?=
 =?utf-8?B?RzlEUi9KMk9taG0wZzZXMFR5dU9CWThsWkhscE1kYy9qeXQ3QWwvREhiSDdO?=
 =?utf-8?B?bmJLSjZCYjI1TEc3bkE4NlA2SjJBbktSMHk3bXNRdmQvNU9PUGcrdDEySnhn?=
 =?utf-8?B?eEt4bmwrRGJiZDRZUDMzNlI4d3o5RWtENXFEMjFxKzY5bm5QWnRuSU56QzVC?=
 =?utf-8?B?dTh5djBGQTBsMEZWb0pTSGhTSVduRTZmRi9qUnJvR1JIaFJJT01sT3BnTVVi?=
 =?utf-8?B?aHhEZ1JDclNKY1ZhVENrK29Ma3orbS9wcklSdmRCbG45ZmJEQ1czZVVGaHow?=
 =?utf-8?B?RWt5Y1lpZjJmb3J4aGlzTHFXMFRLdmZibUFRTkgxMjRGbFRYbldOVkQ4OURZ?=
 =?utf-8?B?NEhLcDlmNkk4N3lZUmJFTHIvTDZJZmNVbm5FVkFmQ2h2VXNEZUdvdE9EY1ZL?=
 =?utf-8?B?T1FHK0hkK2JwK2dtV3JHaDJZbG4wMW1tclR1S09LL1ZXN3g3UXFyVDJUQXEv?=
 =?utf-8?Q?JsWBKspGTSZPzFgUJ/XDdB9Y4YypmU4chCYu3mf?=
X-OriginatorOrg: oracle.com
X-MS-Exchange-CrossTenant-Network-Message-Id: e0c6d445-d103-424f-cd70-08d947b1d6cd
X-MS-Exchange-CrossTenant-AuthSource: BLAPR10MB5009.namprd10.prod.outlook.com
X-MS-Exchange-CrossTenant-AuthAs: Internal
X-MS-Exchange-CrossTenant-OriginalArrivalTime: 15 Jul 2021 16:58:59.0082
 (UTC)
X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted
X-MS-Exchange-CrossTenant-Id: 4e2c6054-71cb-48f1-bd6c-3a9705aca71b
X-MS-Exchange-CrossTenant-MailboxType: HOSTED
X-MS-Exchange-CrossTenant-UserPrincipalName: n+/aIE9t+mfQQfHCoaVaQeITm4FACotAsQJkjFakxWUzmLcIEtlQgvY90vf8YXZiX4SxAJDNcY6cW27XtG912DTd8g9h798M01j2fqRQdxE=
X-MS-Exchange-Transport-CrossTenantHeadersStamped: MN2PR10MB4029
X-Proofpoint-Virus-Version: vendor=nai engine=6200 definitions=10046 signatures=668682
X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 phishscore=0 bulkscore=0 malwarescore=0
 spamscore=0 suspectscore=0 adultscore=0 mlxlogscore=999 mlxscore=0
 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2104190000
 definitions=main-2107150116
X-Proofpoint-GUID: bdsWZfvxQy0DFOdpS8eLfimtmJJWt2xt
X-Proofpoint-ORIG-GUID: bdsWZfvxQy0DFOdpS8eLfimtmJJWt2xt
Precedence: bulk
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org


On 7/15/21 3:39 AM, Roman Skakun wrote:
>> This looks like it wasn't picked up? Should it go in rc1?
> Hi, Konrad!
>
> This looks like an unambiguous bug, and should be in rc1.


Looks like you didn't copy Christoph which could be part of the problem. Adding him.


-boris


>
> Cheers!
>
> ср, 14 июл. 2021 г. в 03:15, Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>:
>> On Tue, Jun 22, 2021 at 04:34:14PM +0300, Roman Skakun wrote:
>>> This commit is dedicated to fix incorrect conversion from
>>> cpu_addr to page address in cases when we get virtual
>>> address which allocated in the vmalloc range.
>>> As the result, virt_to_page() cannot convert this address
>>> properly and return incorrect page address.
>>>
>>> Need to detect such cases and obtains the page address using
>>> vmalloc_to_page() instead.
>>>
>>> Signed-off-by: Roman Skakun <roman_skakun@epam.com>
>>> Reviewed-by: Andrii Anisov <andrii_anisov@epam.com>
>>> ---
>>> Hey!
>>> Thanks for suggestions, Christoph!
>>> I updated the patch according to your advice.
>>> But, I'm so surprised because nobody catches this problem
>>> in the common code before. It looks a bit strange as for me.
>> This looks like it wasn't picked up? Should it go in rc1?
>>>
>>>  kernel/dma/ops_helpers.c | 12 ++++++++++--
>>>  1 file changed, 10 insertions(+), 2 deletions(-)
>>>
>>> diff --git a/kernel/dma/ops_helpers.c b/kernel/dma/ops_helpers.c
>>> index 910ae69cae77..782728d8a393 100644
>>> --- a/kernel/dma/ops_helpers.c
>>> +++ b/kernel/dma/ops_helpers.c
>>> @@ -5,6 +5,14 @@
>>>   */
>>>  #include <linux/dma-map-ops.h>
>>>
>>> +static struct page *cpu_addr_to_page(void *cpu_addr)
>>> +{
>>> +     if (is_vmalloc_addr(cpu_addr))
>>> +             return vmalloc_to_page(cpu_addr);
>>> +     else
>>> +             return virt_to_page(cpu_addr);
>>> +}
>>> +
>>>  /*
>>>   * Create scatter-list for the already allocated DMA buffer.
>>>   */
>>> @@ -12,7 +20,7 @@ int dma_common_get_sgtable(struct device *dev, struct sg_table *sgt,
>>>                void *cpu_addr, dma_addr_t dma_addr, size_t size,
>>>                unsigned long attrs)
>>>  {
>>> -     struct page *page = virt_to_page(cpu_addr);
>>> +     struct page *page = cpu_addr_to_page(cpu_addr);
>>>       int ret;
>>>
>>>       ret = sg_alloc_table(sgt, 1, GFP_KERNEL);
>>> @@ -43,7 +51,7 @@ int dma_common_mmap(struct device *dev, struct vm_area_struct *vma,
>>>               return -ENXIO;
>>>
>>>       return remap_pfn_range(vma, vma->vm_start,
>>> -                     page_to_pfn(virt_to_page(cpu_addr)) + vma->vm_pgoff,
>>> +                     page_to_pfn(cpu_addr_to_page(cpu_addr)) + vma->vm_pgoff,
>>>                       user_count << PAGE_SHIFT, vma->vm_page_prot);
>>>  #else
>>>       return -ENXIO;
>>> --
>>> 2.25.1
>>>
>
>