From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id E33FEEB64D8 for ; Wed, 14 Jun 2023 13:22:32 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 5796A10E455; Wed, 14 Jun 2023 13:22:32 +0000 (UTC) Received: from mga05.intel.com (mga05.intel.com [192.55.52.43]) by gabe.freedesktop.org (Postfix) with ESMTPS id 4F85610E455; Wed, 14 Jun 2023 13:22:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1686748950; x=1718284950; h=message-id:date:mime-version:subject:to:cc:references: from:in-reply-to:content-transfer-encoding; bh=krZlgUF812lZ1Msg1luNdv0RZ6yxrI7AK5Nw8giEATI=; b=UDMs43fsWXq0FQ965v2WXm403z8zZhfMfZ/4iOO4qNlQ9oW5K77TcfBj VikN3Scej99lDxoKk3wnYp8/2W3sRfU7GztTF+cVtsYGQIxLDnaWrA3TO 4oVwLDS7ZbCGaGmclrIlbk4S0VE5kQh6c3rDT8ebglzHjyfUHgt1dnwSN VZ6RYqLRYVoT/8bZAhJKsqo8W/er4ccJDlwPfSF4LnWuG8hyq5syS747/ ElAoSO95Ss1/Eu4RzvT3imBPUfys8O8msngQfmZIFUw2Sj3O8GxYoHRes 7cOxXHMIM22i8EX7xwtKtXfIKwz7/FQeh+IjBtzL3XWvrXYvThltwWcDL A==; X-IronPort-AV: E=McAfee;i="6600,9927,10741"; a="444977889" X-IronPort-AV: E=Sophos;i="6.00,242,1681196400"; d="scan'208";a="444977889" Received: from fmsmga003.fm.intel.com ([10.253.24.29]) by fmsmga105.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 14 Jun 2023 06:22:29 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10741"; a="801899074" X-IronPort-AV: E=Sophos;i="6.00,242,1681196400"; d="scan'208";a="801899074" Received: from sobyrne-mobl1.ger.corp.intel.com (HELO [10.213.224.182]) ([10.213.224.182]) by fmsmga003-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 14 Jun 2023 06:22:25 -0700 Message-ID: Date: Wed, 14 Jun 2023 14:22:23 +0100 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.11.0 Content-Language: en-US To: Sumitra Sharma , Jani Nikula , Joonas Lahtinen , Rodrigo Vivi , David Airlie , Daniel Vetter , intel-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org References: <20230614123556.GA381200@sumitra.com> From: Tvrtko Ursulin Organization: Intel Corporation UK Plc In-Reply-To: <20230614123556.GA381200@sumitra.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Subject: Re: [Intel-gfx] [PATCH] drm/i915: Call page_address() on page acquired with GFP_KERNEL flag X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Intel graphics driver community testing & development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Deepak R Varma , Fabio , Thomas Hellstrom , Ira Weiny , Matthew Auld Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" On 14/06/2023 13:35, Sumitra Sharma wrote: > Pages allocated with GFP_KERNEL cannot come from Highmem. > That is why there is no need to call kmap() on them. Are you sure it is GFP_KERNEL backed and not tmpfs? I am not sure myself so let me copy Matt and Thomas if they happen to know off hand. Regards, Tvrtko > Therefore, don't call kmap() on the page coming from > vma_res->bi.pages using for_each_sgt_page() in > i915_vma_coredump_create(). > > Use a plain page_address() to get the kernel address instead. > > Signed-off-by: Sumitra Sharma > --- > drivers/gpu/drm/i915/i915_gpu_error.c | 3 +-- > 1 file changed, 1 insertion(+), 2 deletions(-) > > diff --git a/drivers/gpu/drm/i915/i915_gpu_error.c b/drivers/gpu/drm/i915/i915_gpu_error.c > index f020c0086fbc..6f51cb4fc55c 100644 > --- a/drivers/gpu/drm/i915/i915_gpu_error.c > +++ b/drivers/gpu/drm/i915/i915_gpu_error.c > @@ -1164,9 +1164,8 @@ i915_vma_coredump_create(const struct intel_gt *gt, > > drm_clflush_pages(&page, 1); > > - s = kmap(page); > + s = page_address(page); > ret = compress_page(compress, s, dst, false); > - kunmap(page); > > drm_clflush_pages(&page, 1); >