From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wm0-f52.google.com (mail-wm0-f52.google.com [74.125.82.52]) by dpdk.org (Postfix) with ESMTP id BB7FF2BAC for ; Fri, 1 Jul 2016 14:47:30 +0200 (CEST) Received: by mail-wm0-f52.google.com with SMTP id f126so25263331wma.1 for ; Fri, 01 Jul 2016 05:47:30 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=6wind-com.20150623.gappssmtp.com; s=20150623; h=from:to:cc:subject:date:message-id:user-agent:in-reply-to :references:mime-version:content-transfer-encoding; bh=rZSIK6TBYc8ZaZhDC78VFMfKHSPl+bmy4V+aOR4ZbkY=; b=dfNgMDEcFwNyZApAxqdXVtQy6l2WKZ8UXFoOqvqrfzBr1mfA7Pe9RnhvVvEgZkYQfH W6u7/PTFXLuVFp9zrK1xHDMuAqZlU4lU7pryDoUFOKnh7pPXvqnI9LDYxUGgAdAj835W brxpjpxnbr+KM9jYUuOIp9Ru7H+nQC21diAoK3ognl0Q9PiBxVMOm/byghtdXbzjiijR abxC+MHhQv827rhrIMtI84ErE/YZ4/Wto8+/QnmfL7PqzpQCWrlU+LagQfBTwckq7vQn qwLT4eKsrvGTAcFrUOt1qonJuSrzkxTnrMeu/zB57R4GJUTd+u/t310xMalbgwl71ZJf iSMA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:from:to:cc:subject:date:message-id:user-agent :in-reply-to:references:mime-version:content-transfer-encoding; bh=rZSIK6TBYc8ZaZhDC78VFMfKHSPl+bmy4V+aOR4ZbkY=; b=EqSKAqaEBeFmXvI9KlTfNK0T2VZtfFXg+7f39lNCeaCN1+poMTBG3ZVerELsG+McD9 lcsCyV+kND9Rsic1zGFulj9DZg3hS5z3+okYVhdC9PT+/1ml4T2wTS+BHXH0fKdHdbO+ Xx86UUiocG5W90zxBqAF5tibIw68oKZMJxrj9P6EVb09Np5efUvviBjpbIwXMBOp3EBc eNGNUZMU8RHtMQFe8hWn8TwBmmsOWRdowEPOE6U7v1b2GvES5y/5FiAzus/CW9ZiNJm0 0OtUk5sc8t9oigMJCKQCzGKb+nVeTIf5XtuO+91JaQB04VTF8UH6IBJeuIZUg60AMDGU aXmA== X-Gm-Message-State: ALyK8tJs6Q0Gg39h/8WtQlWzUr/GFuSAXt2vF83fuYCWyuynTarYyS21oIak4zHo+p+gWC1H X-Received: by 10.28.18.199 with SMTP id 190mr20562481wms.66.1467377250511; Fri, 01 Jul 2016 05:47:30 -0700 (PDT) Received: from xps13.localnet (184.203.134.77.rev.sfr.net. [77.134.203.184]) by smtp.gmail.com with ESMTPSA id wo9sm2764463wjb.8.2016.07.01.05.47.29 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Fri, 01 Jul 2016 05:47:29 -0700 (PDT) From: Thomas Monjalon To: Ferruh Yigit Cc: dev@dpdk.org, Stephen Hemminger Date: Fri, 01 Jul 2016 14:47:28 +0200 Message-ID: <4689144.y76TPTqy0y@xps13> User-Agent: KMail/4.14.10 (Linux/4.5.4-1-ARCH; KDE/4.14.11; x86_64; ; ) In-Reply-To: <1467372912-31113-1-git-send-email-ferruh.yigit@intel.com> References: <57764BA3.5030903@intel.com> <1467372912-31113-1-git-send-email-ferruh.yigit@intel.com> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" Subject: Re: [dpdk-dev] [PATCH] igb_uio: fix mmap failure X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: patches and discussions about DPDK List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 01 Jul 2016 12:47:30 -0000 Thank you Ferruh for taking care of igb_uio. 2016-07-01 12:35, Ferruh Yigit: > With kernels enabled CONFIG_IO_STRICT_DEVMEM option mmap the iomem area > to userspace fails: Maybe some words are missing. Please check punctuation of the whole commit message to make it easier to understand. > EAL: pci_map_resource(): > cannot mmap(39, 0x7f1c51800000, 0x100000, 0x0): > Invalid argument (0xffffffffffffffff) > > As a workaround igb_uio can stop reserving PCI memory resources, from > kernel point of view io-memory region looks like idle and mmap works > again. > > With this update device io-memory range is not protected against any > other kernel driver claim ownership on those resources, which shouldn't > be a problem for dpdk usage module. Why it should not be a problem? Please could you give an example of what could happen? This patch fixes a problem with recent kernels (not mentioned above) which offer the uio_pci_generic alternative. That's why I think we should fix it only if there is absolutely no regression for older kernels.