From nobody Tue Apr 7 12:47:35 2026 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 03049C433FE for ; Mon, 17 Oct 2022 09:32:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229788AbiJQJcg (ORCPT ); Mon, 17 Oct 2022 05:32:36 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42718 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231225AbiJQJc2 (ORCPT ); Mon, 17 Oct 2022 05:32:28 -0400 Received: from mga14.intel.com (mga14.intel.com [192.55.52.115]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id ADDC941D03 for ; Mon, 17 Oct 2022 02:32:27 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1665999147; x=1697535147; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=tiW6Fpm0hVgB6aQj9aJLze7KS0YilKpmQTotRlfBNY0=; b=byAIm+CZyqpTzAvFjOrdoEfFq1gPFEXGD2l04JB16wzJKzd0NHZoP/GN JiUy9STG+cSEMWAIJa1qAluPP11aa6hqBQTno6G2aAehNqhctoEVWV19u qj1o3pfk55vYhaVKVaC3pAgCkvuYbXHGIKfcbozNTASnLYv/YH8TGvEhD k0bIGc7W/69qubuimCi8e8Xbv4zRAPUUJz0U2tPUXhLXi5XMEm23gfj5+ 8DJCziH9HnNuMAeNGdQ9FhA40uGmMuEK/uyBuBMVAjBW9yo5wq8uw+xaJ lJviY/ZAJB8m8PKkT5Uro5P8aytCrtwG9ybytQdwMrvzSwWuvEaawTTUh w==; X-IronPort-AV: E=McAfee;i="6500,9779,10502"; a="305741556" X-IronPort-AV: E=Sophos;i="5.95,191,1661842800"; d="scan'208";a="305741556" Received: from fmsmga003.fm.intel.com ([10.253.24.29]) by fmsmga103.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 17 Oct 2022 02:32:27 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6500,9779,10502"; a="717431213" X-IronPort-AV: E=Sophos;i="5.95,191,1661842800"; d="scan'208";a="717431213" Received: from liuzhao-optiplex-7080.sh.intel.com ([10.239.160.132]) by FMSMGA003.fm.intel.com with ESMTP; 17 Oct 2022 02:32:23 -0700 From: Zhao Liu To: Jani Nikula , Joonas Lahtinen , Rodrigo Vivi , Tvrtko Ursulin , David Airlie , Daniel Vetter , Matthew Auld , =?UTF-8?q?Thomas=20Hellstr=C3=B6m?= , Nirmoy Das , Maarten Lankhorst , Chris Wilson , =?UTF-8?q?Christian=20K=C3=B6nig?= , intel-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org Cc: Ira Weiny , "Fabio M . De Francesco" , Zhenyu Wang , Zhao Liu , Dave Hansen Subject: [PATCH 1/9] drm/i915: Use kmap_local_page() in gem/i915_gem_object.c Date: Mon, 17 Oct 2022 17:37:17 +0800 Message-Id: <20221017093726.2070674-2-zhao1.liu@linux.intel.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20221017093726.2070674-1-zhao1.liu@linux.intel.com> References: <20221017093726.2070674-1-zhao1.liu@linux.intel.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" From: Zhao Liu The use of kmap_atomic() is being deprecated in favor of kmap_local_page()[1]. The main difference between atomic and local mappings is that local mappings doesn't disable page faults or preemption. There're 2 reasons why i915_gem_object_read_from_page_kmap() doesn't need to disable pagefaults and preemption for mapping: 1. The flush operation is safe for CPU hotplug when preemption is not disabled. In drm/i915/gem/i915_gem_object.c, the function i915_gem_object_read_from_page_kmap() calls drm_clflush_virt_range() to use CLFLUSHOPT or WBINVD to flush. Since CLFLUSHOPT is global on x86 and WBINVD is called on each cpu in drm_clflush_virt_range(), the flush operation is global and any issue with cpu's being added or removed can be handled safely. 2. Any context switch caused by preemption or sleep (pagefault may cause sleep) doesn't affect the validity of local mapping. Therefore, i915_gem_object_read_from_page_kmap() is a function where the use of kmap_local_page() in place of kmap_atomic() is correctly suited. Convert the calls of kmap_atomic() / kunmap_atomic() to kmap_local_page() / kunmap_local(). And remove the redundant variable that stores the address of the mapped page since kunmap_local() can accept any pointer within the page. [1]: https://lore.kernel.org/all/20220813220034.806698-1-ira.weiny@intel.com Suggested-by: Dave Hansen Suggested-by: Ira Weiny Suggested-by: Fabio M. De Francesco Signed-off-by: Zhao Liu --- Suggested by credits: Dave: Referred to his explanation about cache flush. Ira: Referred to his task document, review comments and explanation about cache flush. Fabio: Referred to his boiler plate commit message. --- drivers/gpu/drm/i915/gem/i915_gem_object.c | 8 +++----- 1 file changed, 3 insertions(+), 5 deletions(-) diff --git a/drivers/gpu/drm/i915/gem/i915_gem_object.c b/drivers/gpu/drm/i= 915/gem/i915_gem_object.c index 369006c5317f..a0072abed75e 100644 --- a/drivers/gpu/drm/i915/gem/i915_gem_object.c +++ b/drivers/gpu/drm/i915/gem/i915_gem_object.c @@ -413,17 +413,15 @@ void __i915_gem_object_invalidate_frontbuffer(struct = drm_i915_gem_object *obj, static void i915_gem_object_read_from_page_kmap(struct drm_i915_gem_object *obj, u64 o= ffset, void *dst, int size) { - void *src_map; void *src_ptr; =20 - src_map =3D kmap_atomic(i915_gem_object_get_page(obj, offset >> PAGE_SHIF= T)); - - src_ptr =3D src_map + offset_in_page(offset); + src_ptr =3D kmap_local_page(i915_gem_object_get_page(obj, offset >> PAGE_= SHIFT)) + + offset_in_page(offset); if (!(obj->cache_coherent & I915_BO_CACHE_COHERENT_FOR_READ)) drm_clflush_virt_range(src_ptr, size); memcpy(dst, src_ptr, size); =20 - kunmap_atomic(src_map); + kunmap_local(src_ptr); } =20 static void --=20 2.34.1 From nobody Tue Apr 7 12:47:35 2026 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id F3D1FC4332F for ; Mon, 17 Oct 2022 09:32:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230101AbiJQJcq (ORCPT ); Mon, 17 Oct 2022 05:32:46 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42784 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230249AbiJQJcc (ORCPT ); Mon, 17 Oct 2022 05:32:32 -0400 Received: from mga14.intel.com (mga14.intel.com [192.55.52.115]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id BF8484DB1B for ; Mon, 17 Oct 2022 02:32:31 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1665999151; x=1697535151; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=L0klkS76Kt8Hk/6E4tsClEGhD8s9Fs2w8vteQwCBE8U=; b=F3/6TfLJzL35a+a164pxBFAFgFAIRQKvmyBY5u6X8V5b2WfUFO+IqwNd t6nUkcRPMPdqLmUWJcKz3/MGF0yug1+MCybH0YMKFUkDh/riaa6/DY7sd FMhf5dj9cYbFIAXe3Ov7aDrlxxcI69egrFhP9Xz2KinFzujraqsf2WyEg 2NrnWjnIv3UTIAkc4dyLsGKNGEFTkwWt/DCjgfRVYlibKxH1obKRHBKHz YK7B42adFL7E8sP673f3qV4aVqkrO8o4wdu/cCc3CvgMqNjbu1YujM1iP WNcNn4Lvbpty/VS2HDOLQi18lxKkZJHXGpdQmjH5uQonTAIHxFDtur3lY w==; X-IronPort-AV: E=McAfee;i="6500,9779,10502"; a="305741570" X-IronPort-AV: E=Sophos;i="5.95,191,1661842800"; d="scan'208";a="305741570" Received: from fmsmga003.fm.intel.com ([10.253.24.29]) by fmsmga103.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 17 Oct 2022 02:32:31 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6500,9779,10502"; a="717431229" X-IronPort-AV: E=Sophos;i="5.95,191,1661842800"; d="scan'208";a="717431229" Received: from liuzhao-optiplex-7080.sh.intel.com ([10.239.160.132]) by FMSMGA003.fm.intel.com with ESMTP; 17 Oct 2022 02:32:27 -0700 From: Zhao Liu To: Jani Nikula , Joonas Lahtinen , Rodrigo Vivi , Tvrtko Ursulin , David Airlie , Daniel Vetter , Matthew Auld , =?UTF-8?q?Thomas=20Hellstr=C3=B6m?= , Nirmoy Das , Maarten Lankhorst , Chris Wilson , =?UTF-8?q?Christian=20K=C3=B6nig?= , intel-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org Cc: Ira Weiny , "Fabio M . De Francesco" , Zhenyu Wang , Zhao Liu , Dave Hansen Subject: [PATCH 2/9] drm/i915: Use kmap_local_page() in gem/i915_gem_pyhs.c Date: Mon, 17 Oct 2022 17:37:18 +0800 Message-Id: <20221017093726.2070674-3-zhao1.liu@linux.intel.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20221017093726.2070674-1-zhao1.liu@linux.intel.com> References: <20221017093726.2070674-1-zhao1.liu@linux.intel.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" From: Zhao Liu The use of kmap_atomic() is being deprecated in favor of kmap_local_page()[1]. The main difference between atomic and local mappings is that local mappings doesn't disable page faults or preemption. In drm/i915/gem/i915_gem_phys.c, the functions i915_gem_object_get_pages_phys() and i915_gem_object_put_pages_phys() don't need to disable pagefaults and preemption for mapping because of these 2 reasons: 1. The flush operation is safe for CPU hotplug when preemption is not disabled. In drm/i915/gem/i915_gem_object.c, the functions i915_gem_object_get_pages_phys() and i915_gem_object_put_pages_phys() calls drm_clflush_virt_range() to use CLFLUSHOPT or WBINVD to flush. Since CLFLUSHOPT is global on x86 and WBINVD is called on each cpu in drm_clflush_virt_range(), the flush operation is global and any issue with cpu's being added or removed can be handled safely. 2. Any context switch caused by preemption or sleep (pagefault may cause sleep) doesn't affect the validity of local mapping. Therefore, i915_gem_object_get_pages_phys() and i915_gem_object_put_pages_phys() are two functions where the use of kmap_local_page() in place of kmap_atomic() is correctly suited. Convert the calls of kmap_atomic() / kunmap_atomic() to kmap_local_page() / kunmap_local(). [1]: https://lore.kernel.org/all/20220813220034.806698-1-ira.weiny@intel.com Suggested-by: Dave Hansen Suggested-by: Ira Weiny Suggested-by: Fabio M. De Francesco Signed-off-by: Zhao Liu --- Suggested by credits: Dave: Referred to his explanation about cache flush. Ira: Referred to his task document, review comments and explanation about cache flush. Fabio: Referred to his boiler plate commit message. --- drivers/gpu/drm/i915/gem/i915_gem_phys.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/drivers/gpu/drm/i915/gem/i915_gem_phys.c b/drivers/gpu/drm/i91= 5/gem/i915_gem_phys.c index 0d0e46dae559..d602ba19ecb2 100644 --- a/drivers/gpu/drm/i915/gem/i915_gem_phys.c +++ b/drivers/gpu/drm/i915/gem/i915_gem_phys.c @@ -66,10 +66,10 @@ static int i915_gem_object_get_pages_phys(struct drm_i9= 15_gem_object *obj) if (IS_ERR(page)) goto err_st; =20 - src =3D kmap_atomic(page); + src =3D kmap_local_page(page); memcpy(dst, src, PAGE_SIZE); drm_clflush_virt_range(dst, PAGE_SIZE); - kunmap_atomic(src); + kunmap_local(src); =20 put_page(page); dst +=3D PAGE_SIZE; @@ -114,10 +114,10 @@ i915_gem_object_put_pages_phys(struct drm_i915_gem_ob= ject *obj, if (IS_ERR(page)) continue; =20 - dst =3D kmap_atomic(page); + dst =3D kmap_local_page(page); drm_clflush_virt_range(src, PAGE_SIZE); memcpy(dst, src, PAGE_SIZE); - kunmap_atomic(dst); + kunmap_local(dst); =20 set_page_dirty(page); if (obj->mm.madv =3D=3D I915_MADV_WILLNEED) --=20 2.34.1 From nobody Tue Apr 7 12:47:35 2026 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 24A9BC433FE for ; Mon, 17 Oct 2022 09:32:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230102AbiJQJct (ORCPT ); Mon, 17 Oct 2022 05:32:49 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42772 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231191AbiJQJcm (ORCPT ); Mon, 17 Oct 2022 05:32:42 -0400 Received: from mga14.intel.com (mga14.intel.com [192.55.52.115]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8D86752802 for ; Mon, 17 Oct 2022 02:32:35 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1665999155; x=1697535155; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=h0hmpKyvdxb2sKw8lROgYrffCQobTfXddN7YtzQHU7M=; b=Ul4mgQ2PEWvaEHTyCXo+CpuOqncgpmy7bqoqyJLIaDvc0LS0uGxTBa7q xGSfbEPWNDAcbn1EEklVi0+OMzGQrUCwC0UJsMs2Y3UJXHXkmcmWjbf+3 q4h6zIyS//A0GM0phFQyG5AK8OTNT+c2epftNrFUT3LZX7miEC78ZOl8P kEIDverLDm6dOPMNvmufC2NmtxTFfT+m8RjLr0K2qUO+960SQ2KpFAfc3 KFJMkB8dudpBdwUaa/MAiNouKZvB0bJAT3yCKYL03HjtWraAlISk/hzER tRzANd8yFzjNhkAu2ReA1klGptaBniNjOwGSElWB7WE4V+sg34MFboUHz Q==; X-IronPort-AV: E=McAfee;i="6500,9779,10502"; a="305741585" X-IronPort-AV: E=Sophos;i="5.95,191,1661842800"; d="scan'208";a="305741585" Received: from fmsmga003.fm.intel.com ([10.253.24.29]) by fmsmga103.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 17 Oct 2022 02:32:35 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6500,9779,10502"; a="717431242" X-IronPort-AV: E=Sophos;i="5.95,191,1661842800"; d="scan'208";a="717431242" Received: from liuzhao-optiplex-7080.sh.intel.com ([10.239.160.132]) by FMSMGA003.fm.intel.com with ESMTP; 17 Oct 2022 02:32:31 -0700 From: Zhao Liu To: Jani Nikula , Joonas Lahtinen , Rodrigo Vivi , Tvrtko Ursulin , David Airlie , Daniel Vetter , Matthew Auld , =?UTF-8?q?Thomas=20Hellstr=C3=B6m?= , Nirmoy Das , Maarten Lankhorst , Chris Wilson , =?UTF-8?q?Christian=20K=C3=B6nig?= , intel-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org Cc: Ira Weiny , "Fabio M . De Francesco" , Zhenyu Wang , Zhao Liu Subject: [PATCH 3/9] drm/i915: Use kmap_local_page() in gem/i915_gem_shmem.c Date: Mon, 17 Oct 2022 17:37:19 +0800 Message-Id: <20221017093726.2070674-4-zhao1.liu@linux.intel.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20221017093726.2070674-1-zhao1.liu@linux.intel.com> References: <20221017093726.2070674-1-zhao1.liu@linux.intel.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" From: Zhao Liu The use of kmap_atomic() is being deprecated in favor of kmap_local_page()[1]. The main difference between atomic and local mappings is that local mappings doesn't disable page faults or preemption. In drm/i915/gem/i915_gem_shmem.c, the function shmem_pwrite() need to disable pagefault to eliminate the potential recursion fault[2]. But here __copy_from_user_inatomic() doesn't need to disable preemption and local mapping is valid for sched in/out. So it can use kmap_local_page() / kunmap_local() with pagefault_disable() / pagefault_enable() to replace atomic mapping. [1]: https://lore.kernel.org/all/20220813220034.806698-1-ira.weiny@intel.com [2]: https://patchwork.freedesktop.org/patch/295840/ Suggested-by: Ira Weiny Signed-off-by: Zhao Liu Reviewed-by: Fabio M. De Francesco Reviewed-by: Ira Weiny --- Suggested by credits: Ira: Referred to his suggestions about keeping pagefault_disable(). --- drivers/gpu/drm/i915/gem/i915_gem_shmem.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/i915/gem/i915_gem_shmem.c b/drivers/gpu/drm/i9= 15/gem/i915_gem_shmem.c index f42ca1179f37..e279a3e30c02 100644 --- a/drivers/gpu/drm/i915/gem/i915_gem_shmem.c +++ b/drivers/gpu/drm/i915/gem/i915_gem_shmem.c @@ -472,11 +472,13 @@ shmem_pwrite(struct drm_i915_gem_object *obj, if (err < 0) return err; =20 - vaddr =3D kmap_atomic(page); + vaddr =3D kmap_local_page(page); + pagefault_disable(); unwritten =3D __copy_from_user_inatomic(vaddr + pg, user_data, len); - kunmap_atomic(vaddr); + pagefault_enable(); + kunmap_local(vaddr); =20 err =3D aops->write_end(obj->base.filp, mapping, offset, len, len - unwritten, page, data); --=20 2.34.1 From nobody Tue Apr 7 12:47:35 2026 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 989FAC43217 for ; Mon, 17 Oct 2022 09:32:54 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231313AbiJQJcx (ORCPT ); Mon, 17 Oct 2022 05:32:53 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42782 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231317AbiJQJcn (ORCPT ); Mon, 17 Oct 2022 05:32:43 -0400 Received: from mga14.intel.com (mga14.intel.com [192.55.52.115]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0C95B58DD6 for ; Mon, 17 Oct 2022 02:32:39 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1665999160; x=1697535160; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=ZXOTrqnB1S2hiIrW6AdSeUKTfgzUpr1fFCYC+QaCffw=; b=ZBVwtOMGjrVr/Cz2gSBb3HB2GjVyFD7+JWmQLxCVebjsKl9DAgl7YpPt 3aMUVr4eAKuZFIVzGNxsy0Gv2mOr3nF+hcrazTVmdiQkVmHlyFCyeZet+ go+nOOlgUjQeGjbp5ioISj6r1FrAgAlN+HEGEeun8O+AiAQXNkLA99cv4 VpzaMc6Nzwe/WCTlyS3XBXIG0yKjaNK6oIcbPoFmckcs/K/5vZOC0PS8U BRHsMo5Ze2MQdZMksRnSJ6eIn9f5whqe1nWMeujyJiwxCiA+6o+FiKhsF QHXSG6ED1SuY2J62KZg3FwJc4Murj2fNefBEsek8n94BYaYkigU3EXRnB Q==; X-IronPort-AV: E=McAfee;i="6500,9779,10502"; a="305741593" X-IronPort-AV: E=Sophos;i="5.95,191,1661842800"; d="scan'208";a="305741593" Received: from fmsmga003.fm.intel.com ([10.253.24.29]) by fmsmga103.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 17 Oct 2022 02:32:39 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6500,9779,10502"; a="717431262" X-IronPort-AV: E=Sophos;i="5.95,191,1661842800"; d="scan'208";a="717431262" Received: from liuzhao-optiplex-7080.sh.intel.com ([10.239.160.132]) by FMSMGA003.fm.intel.com with ESMTP; 17 Oct 2022 02:32:35 -0700 From: Zhao Liu To: Jani Nikula , Joonas Lahtinen , Rodrigo Vivi , Tvrtko Ursulin , David Airlie , Daniel Vetter , Matthew Auld , =?UTF-8?q?Thomas=20Hellstr=C3=B6m?= , Nirmoy Das , Maarten Lankhorst , Chris Wilson , =?UTF-8?q?Christian=20K=C3=B6nig?= , intel-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org Cc: Ira Weiny , "Fabio M . De Francesco" , Zhenyu Wang , Zhao Liu , Dave Hansen Subject: [PATCH 4/9] drm/i915: Use kmap_local_page() in gem/selftests/huge_pages.c Date: Mon, 17 Oct 2022 17:37:20 +0800 Message-Id: <20221017093726.2070674-5-zhao1.liu@linux.intel.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20221017093726.2070674-1-zhao1.liu@linux.intel.com> References: <20221017093726.2070674-1-zhao1.liu@linux.intel.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" From: Zhao Liu The use of kmap_atomic() is being deprecated in favor of kmap_local_page()[1]. The main difference between atomic and local mappings is that local mappings doesn't disable page faults or preemption. In drm/i915/gem/selftests/huge_pages.c, function __cpu_check_shmem() mainly uses mapping to flush cache and check the value. There're 2 reasons why __cpu_check_shmem() doesn't need to disable pagefaults and preemption for mapping: 1. The flush operation is safe for CPU hotplug when preemption is not disabled. Function __cpu_check_shmem() calls drm_clflush_virt_range() to use CLFLUSHOPT or WBINVD to flush. Since CLFLUSHOPT is global on x86 and WBINVD is called on each cpu in drm_clflush_virt_range(), the flush operation is global and any issue with cpu's being added or removed can be handled safely. 2. Any context switch caused by preemption or sleep (pagefault may cause sleep) doesn't affect the validity of local mapping. Therefore, __cpu_check_shmem() is a function where the use of kmap_local_page() in place of kmap_atomic() is correctly suited. Convert the calls of kmap_atomic() / kunmap_atomic() to kmap_local_page() / kunmap_local(). [1]: https://lore.kernel.org/all/20220813220034.806698-1-ira.weiny@intel.com Suggested-by: Dave Hansen Suggested-by: Ira Weiny Suggested-by: Fabio M. De Francesco Signed-off-by: Zhao Liu --- Suggested by credits: Dave: Referred to his explanation about cache flush. Ira: Referred to his task document, review comments and explanation about cache flush. Fabio: Referred to his boiler plate commit message. --- drivers/gpu/drm/i915/gem/selftests/huge_pages.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/i915/gem/selftests/huge_pages.c b/drivers/gpu/= drm/i915/gem/selftests/huge_pages.c index c570cf780079..6f4efe905105 100644 --- a/drivers/gpu/drm/i915/gem/selftests/huge_pages.c +++ b/drivers/gpu/drm/i915/gem/selftests/huge_pages.c @@ -1022,7 +1022,7 @@ __cpu_check_shmem(struct drm_i915_gem_object *obj, u3= 2 dword, u32 val) goto err_unlock; =20 for (n =3D 0; n < obj->base.size >> PAGE_SHIFT; ++n) { - u32 *ptr =3D kmap_atomic(i915_gem_object_get_page(obj, n)); + u32 *ptr =3D kmap_local_page(i915_gem_object_get_page(obj, n)); =20 if (needs_flush & CLFLUSH_BEFORE) drm_clflush_virt_range(ptr, PAGE_SIZE); @@ -1030,12 +1030,12 @@ __cpu_check_shmem(struct drm_i915_gem_object *obj, = u32 dword, u32 val) if (ptr[dword] !=3D val) { pr_err("n=3D%lu ptr[%u]=3D%u, val=3D%u\n", n, dword, ptr[dword], val); - kunmap_atomic(ptr); + kunmap_local(ptr); err =3D -EINVAL; break; } =20 - kunmap_atomic(ptr); + kunmap_local(ptr); } =20 i915_gem_object_finish_access(obj); --=20 2.34.1 From nobody Tue Apr 7 12:47:35 2026 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 65C8EC4332F for ; Mon, 17 Oct 2022 09:32:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230087AbiJQJc4 (ORCPT ); Mon, 17 Oct 2022 05:32:56 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42784 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231298AbiJQJcp (ORCPT ); Mon, 17 Oct 2022 05:32:45 -0400 Received: from mga14.intel.com (mga14.intel.com [192.55.52.115]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 28B9446632 for ; Mon, 17 Oct 2022 02:32:44 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1665999164; x=1697535164; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=Qa17WTfuPuByL/pGxqJjZfPv2fBRDy/8RHd7BwsgD1E=; b=AoE485pcIrMn+qUcfTmyZ55ZUcGRRjDdAIMlg6nPbId6mCkR1PMayGiX yA/4Y5zJ/4Ko50nVGRf6C0M3SKP3bauloEu1bOOZGxc4JbytLDEHqPg+p gBMQOP9+3Oi8N+UHAqoF1GgZyHnpHGS0vY6ySVHZHKUr27xmHJK4cmMoP 3ByHnNk6/fCOW45oruW1uDTra2wTji9BxhkKWv57iDKYou7imQtZPBcno eIHiF2sg4otnbT8Y5UsUF1+hORorSWENHr1fzK/VvLzl3qUwRIJXvG8ys VsVwPgP21LGHWIx9a2oA3DW4gG9xJSylEUucX6MsDd2Tlb2eZJu8TiUsx Q==; X-IronPort-AV: E=McAfee;i="6500,9779,10502"; a="305741608" X-IronPort-AV: E=Sophos;i="5.95,191,1661842800"; d="scan'208";a="305741608" Received: from fmsmga003.fm.intel.com ([10.253.24.29]) by fmsmga103.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 17 Oct 2022 02:32:43 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6500,9779,10502"; a="717431281" X-IronPort-AV: E=Sophos;i="5.95,191,1661842800"; d="scan'208";a="717431281" Received: from liuzhao-optiplex-7080.sh.intel.com ([10.239.160.132]) by FMSMGA003.fm.intel.com with ESMTP; 17 Oct 2022 02:32:39 -0700 From: Zhao Liu To: Jani Nikula , Joonas Lahtinen , Rodrigo Vivi , Tvrtko Ursulin , David Airlie , Daniel Vetter , Matthew Auld , =?UTF-8?q?Thomas=20Hellstr=C3=B6m?= , Nirmoy Das , Maarten Lankhorst , Chris Wilson , =?UTF-8?q?Christian=20K=C3=B6nig?= , intel-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org Cc: Ira Weiny , "Fabio M . De Francesco" , Zhenyu Wang , Zhao Liu , Dave Hansen Subject: [PATCH 5/9] drm/i915: Use kmap_local_page() in gem/selftests/i915_gem_coherency.c Date: Mon, 17 Oct 2022 17:37:21 +0800 Message-Id: <20221017093726.2070674-6-zhao1.liu@linux.intel.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20221017093726.2070674-1-zhao1.liu@linux.intel.com> References: <20221017093726.2070674-1-zhao1.liu@linux.intel.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" From: Zhao Liu The use of kmap_atomic() is being deprecated in favor of kmap_local_page()[1]. The main difference between atomic and local mappings is that local mappings doesn't disable page faults or preemption. In drm/i915/gem/selftests/i915_gem_coherency.c, functions cpu_set() and cpu_get() mainly uses mapping to flush cache and assign the value. There're 2 reasons why cpu_set() and cpu_get() don't need to disable pagefaults and preemption for mapping: 1. The flush operation is safe for CPU hotplug when preemption is not disabled. cpu_set() and cpu_get() call drm_clflush_virt_range() to use CLFLUSHOPT or WBINVD to flush. Since CLFLUSHOPT is global on x86 and WBINVD is called on each cpu in drm_clflush_virt_range(), the flush operation is global and any issue with cpu's being added or removed can be handled safely. 2. Any context switch caused by preemption or sleep (pagefault may cause sleep) doesn't affect the validity of local mapping. Therefore, cpu_set() and cpu_get() are functions where the use of kmap_local_page() in place of kmap_atomic() is correctly suited. Convert the calls of kmap_atomic() / kunmap_atomic() to kmap_local_page() / kunmap_local(). [1]: https://lore.kernel.org/all/20220813220034.806698-1-ira.weiny@intel.com Suggested-by: Dave Hansen Suggested-by: Ira Weiny Suggested-by: Fabio M. De Francesco Signed-off-by: Zhao Liu --- Suggested by credits: Dave: Referred to his explanation about cache flush. Ira: Referred to his task document, review comments and explanation about cache flush. Fabio: Referred to his boiler plate commit message. --- .../gpu/drm/i915/gem/selftests/i915_gem_coherency.c | 12 ++++-------- 1 file changed, 4 insertions(+), 8 deletions(-) diff --git a/drivers/gpu/drm/i915/gem/selftests/i915_gem_coherency.c b/driv= ers/gpu/drm/i915/gem/selftests/i915_gem_coherency.c index a666d7e610f5..b12402c74424 100644 --- a/drivers/gpu/drm/i915/gem/selftests/i915_gem_coherency.c +++ b/drivers/gpu/drm/i915/gem/selftests/i915_gem_coherency.c @@ -24,7 +24,6 @@ static int cpu_set(struct context *ctx, unsigned long off= set, u32 v) { unsigned int needs_clflush; struct page *page; - void *map; u32 *cpu; int err; =20 @@ -34,8 +33,7 @@ static int cpu_set(struct context *ctx, unsigned long off= set, u32 v) goto out; =20 page =3D i915_gem_object_get_page(ctx->obj, offset >> PAGE_SHIFT); - map =3D kmap_atomic(page); - cpu =3D map + offset_in_page(offset); + cpu =3D kmap_local_page(page) + offset_in_page(offset); =20 if (needs_clflush & CLFLUSH_BEFORE) drm_clflush_virt_range(cpu, sizeof(*cpu)); @@ -45,7 +43,7 @@ static int cpu_set(struct context *ctx, unsigned long off= set, u32 v) if (needs_clflush & CLFLUSH_AFTER) drm_clflush_virt_range(cpu, sizeof(*cpu)); =20 - kunmap_atomic(map); + kunmap_local(cpu); i915_gem_object_finish_access(ctx->obj); =20 out: @@ -57,7 +55,6 @@ static int cpu_get(struct context *ctx, unsigned long off= set, u32 *v) { unsigned int needs_clflush; struct page *page; - void *map; u32 *cpu; int err; =20 @@ -67,15 +64,14 @@ static int cpu_get(struct context *ctx, unsigned long o= ffset, u32 *v) goto out; =20 page =3D i915_gem_object_get_page(ctx->obj, offset >> PAGE_SHIFT); - map =3D kmap_atomic(page); - cpu =3D map + offset_in_page(offset); + cpu =3D kmap_local_page(page) + offset_in_page(offset); =20 if (needs_clflush & CLFLUSH_BEFORE) drm_clflush_virt_range(cpu, sizeof(*cpu)); =20 *v =3D *cpu; =20 - kunmap_atomic(map); + kunmap_local(cpu); i915_gem_object_finish_access(ctx->obj); =20 out: --=20 2.34.1 From nobody Tue Apr 7 12:47:35 2026 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6E7F8C4332F for ; Mon, 17 Oct 2022 09:33:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231343AbiJQJdF (ORCPT ); Mon, 17 Oct 2022 05:33:05 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43136 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231304AbiJQJcu (ORCPT ); Mon, 17 Oct 2022 05:32:50 -0400 Received: from mga14.intel.com (mga14.intel.com [192.55.52.115]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B9E0A53D14 for ; Mon, 17 Oct 2022 02:32:48 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1665999168; x=1697535168; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=KW/vA0zXivrgHf+ZcWE46VMbBD0S6IoDScJkHoJEmxA=; b=BaZt/XIxFWbxluyydED/EOzxWFV1nuSHg3lFe+2xXBrvc0X6Y2MPZTZn b9ISGTSFA+yWOrmEf60LUA2PV0EdH1BfP88jUYYgz58mG307aSswsvQ9+ 06O19IXRnHQUFU5KqGtXCNA3ujoKMtSUD9bTcmK/jjuDA6t3J9rQxobLd fbjQjvmmGFu+UDnO8xkatMHIBuBsZ2xWgKFZIlh7E9DuLZVJnzG58Jd07 AfYSWh01H10ToNdJ3Glm0c6dGvARQ9+VviuhsJwFzAO2BKyN1Xku6dFga zjSAasr2HyEN9hyoEyUPubzHk8r3OawnAUqvyeW6jF3k+ecJZipVrx/MS g==; X-IronPort-AV: E=McAfee;i="6500,9779,10502"; a="305741620" X-IronPort-AV: E=Sophos;i="5.95,191,1661842800"; d="scan'208";a="305741620" Received: from fmsmga003.fm.intel.com ([10.253.24.29]) by fmsmga103.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 17 Oct 2022 02:32:48 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6500,9779,10502"; a="717431302" X-IronPort-AV: E=Sophos;i="5.95,191,1661842800"; d="scan'208";a="717431302" Received: from liuzhao-optiplex-7080.sh.intel.com ([10.239.160.132]) by FMSMGA003.fm.intel.com with ESMTP; 17 Oct 2022 02:32:44 -0700 From: Zhao Liu To: Jani Nikula , Joonas Lahtinen , Rodrigo Vivi , Tvrtko Ursulin , David Airlie , Daniel Vetter , Matthew Auld , =?UTF-8?q?Thomas=20Hellstr=C3=B6m?= , Nirmoy Das , Maarten Lankhorst , Chris Wilson , =?UTF-8?q?Christian=20K=C3=B6nig?= , intel-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org Cc: Ira Weiny , "Fabio M . De Francesco" , Zhenyu Wang , Zhao Liu , Dave Hansen Subject: [PATCH 6/9] drm/i915: Use kmap_local_page() in gem/selftests/i915_gem_context.c Date: Mon, 17 Oct 2022 17:37:22 +0800 Message-Id: <20221017093726.2070674-7-zhao1.liu@linux.intel.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20221017093726.2070674-1-zhao1.liu@linux.intel.com> References: <20221017093726.2070674-1-zhao1.liu@linux.intel.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" From: Zhao Liu The use of kmap_atomic() is being deprecated in favor of kmap_local_page()[1]. The main difference between atomic and local mappings is that local mappings doesn't disable page faults or preemption. In drm/i915/gem/selftests/i915_gem_context.c, functions cpu_fill() and cpu_check() mainly uses mapping to flush cache and check/assign the value. There're 2 reasons why cpu_fill() and cpu_check() don't need to disable pagefaults and preemption for mapping: 1. The flush operation is safe for CPU hotplug when preemption is not disabled. cpu_fill() and cpu_check() call drm_clflush_virt_range() to use CLFLUSHOPT or WBINVD to flush. Since CLFLUSHOPT is global on x86 and WBINVD is called on each cpu in drm_clflush_virt_range(), the flush operation is global and any issue with cpu's being added or removed can be handled safely. 2. Any context switch caused by preemption or sleep (pagefault may cause sleep) doesn't affect the validity of local mapping. Therefore, cpu_fill() and cpu_check() are functions where the use of kmap_local_page() in place of kmap_atomic() is correctly suited. Convert the calls of kmap_atomic() / kunmap_atomic() to kmap_local_page() / kunmap_local(). [1]: https://lore.kernel.org/all/20220813220034.806698-1-ira.weiny@intel.com Suggested-by: Dave Hansen Suggested-by: Ira Weiny Suggested-by: Fabio M. De Francesco Signed-off-by: Zhao Liu --- Suggested by credits: Dave: Referred to his explanation about cache flush. Ira: Referred to his task document, review comments and explanation about cache flush. Fabio: Referred to his boiler plate commit message. --- drivers/gpu/drm/i915/gem/selftests/i915_gem_context.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/drivers/gpu/drm/i915/gem/selftests/i915_gem_context.c b/driver= s/gpu/drm/i915/gem/selftests/i915_gem_context.c index c6ad67b90e8a..736337f23f78 100644 --- a/drivers/gpu/drm/i915/gem/selftests/i915_gem_context.c +++ b/drivers/gpu/drm/i915/gem/selftests/i915_gem_context.c @@ -466,12 +466,12 @@ static int cpu_fill(struct drm_i915_gem_object *obj, = u32 value) for (n =3D 0; n < real_page_count(obj); n++) { u32 *map; =20 - map =3D kmap_atomic(i915_gem_object_get_page(obj, n)); + map =3D kmap_local_page(i915_gem_object_get_page(obj, n)); for (m =3D 0; m < DW_PER_PAGE; m++) map[m] =3D value; if (!has_llc) drm_clflush_virt_range(map, PAGE_SIZE); - kunmap_atomic(map); + kunmap_local(map); } =20 i915_gem_object_finish_access(obj); @@ -496,7 +496,7 @@ static noinline int cpu_check(struct drm_i915_gem_objec= t *obj, for (n =3D 0; n < real_page_count(obj); n++) { u32 *map; =20 - map =3D kmap_atomic(i915_gem_object_get_page(obj, n)); + map =3D kmap_local_page(i915_gem_object_get_page(obj, n)); if (needs_flush & CLFLUSH_BEFORE) drm_clflush_virt_range(map, PAGE_SIZE); =20 @@ -522,7 +522,7 @@ static noinline int cpu_check(struct drm_i915_gem_objec= t *obj, } =20 out_unmap: - kunmap_atomic(map); + kunmap_local(map); if (err) break; } --=20 2.34.1 From nobody Tue Apr 7 12:47:35 2026 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 35C09C4332F for ; Mon, 17 Oct 2022 09:33:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231396AbiJQJdW (ORCPT ); Mon, 17 Oct 2022 05:33:22 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43672 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231346AbiJQJdH (ORCPT ); Mon, 17 Oct 2022 05:33:07 -0400 Received: from mga14.intel.com (mga14.intel.com [192.55.52.115]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A5ABA58DDA for ; Mon, 17 Oct 2022 02:32:52 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1665999172; x=1697535172; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=w7/TXOlwKuSkPVUCwoST/WEVHFeOcyRbxSbjIiLRy7U=; b=PrqjAqatzmj+SDSe7Zmp0LLH3c6tgxjGuGgJSJEmAO7DoyDCCAB2rSIU rjM1mm1xQ0xNTH1weArVIFuy8hads1OPRXplQ/LDEpcKh6wt/VRvUNKFl Aw0da7Mz1NaXYQLfGriz90/MwEtO3FbOTqwBFEQgiUrhT34L4wijhs89V 0K4+rATJZUQFeYNnkWIqW74OttLC+WHYOXrqNFc4aU1z/maCjsowI+cLE pGOIdfULdGhP8jAfkn0+ijPC6RHbWsZQxKW6vs0HfnTfUGtXuf29iBxdi Ef3dg1064iC07Zzi4qvLVSSs7DQrd3/dJasu34ZPN+91blw+NBgh//9Ue g==; X-IronPort-AV: E=McAfee;i="6500,9779,10502"; a="305741632" X-IronPort-AV: E=Sophos;i="5.95,191,1661842800"; d="scan'208";a="305741632" Received: from fmsmga003.fm.intel.com ([10.253.24.29]) by fmsmga103.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 17 Oct 2022 02:32:52 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6500,9779,10502"; a="717431321" X-IronPort-AV: E=Sophos;i="5.95,191,1661842800"; d="scan'208";a="717431321" Received: from liuzhao-optiplex-7080.sh.intel.com ([10.239.160.132]) by FMSMGA003.fm.intel.com with ESMTP; 17 Oct 2022 02:32:48 -0700 From: Zhao Liu To: Jani Nikula , Joonas Lahtinen , Rodrigo Vivi , Tvrtko Ursulin , David Airlie , Daniel Vetter , Matthew Auld , =?UTF-8?q?Thomas=20Hellstr=C3=B6m?= , Nirmoy Das , Maarten Lankhorst , Chris Wilson , =?UTF-8?q?Christian=20K=C3=B6nig?= , intel-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org Cc: Ira Weiny , "Fabio M . De Francesco" , Zhenyu Wang , Zhao Liu Subject: [PATCH 7/9] drm/i915: Use memcpy_from_page() in gt/uc/intel_uc_fw.c Date: Mon, 17 Oct 2022 17:37:23 +0800 Message-Id: <20221017093726.2070674-8-zhao1.liu@linux.intel.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20221017093726.2070674-1-zhao1.liu@linux.intel.com> References: <20221017093726.2070674-1-zhao1.liu@linux.intel.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" From: Zhao Liu The use of kmap_atomic() is being deprecated in favor of kmap_local_page()[1]. The main difference between atomic and local mappings is that local mappings doesn't disable page faults or preemption. In drm/i915/gt/uc/intel_us_fw.c, the function intel_uc_fw_copy_rsa() just use the mapping to do memory copy so it doesn't need to disable pagefaults and preemption for mapping. Thus the local mapping without atomic context (not disable pagefaults / preemption) is enough. Therefore, intel_uc_fw_copy_rsa() is a function where the use of memcpy_from_page() with kmap_local_page() in place of memcpy() with kmap_atomic() is correctly suited. Convert the calls of memcpy() with kmap_atomic() / kunmap_atomic() to memcpy_from_page() which uses local mapping to copy. [1]: https://lore.kernel.org/all/20220813220034.806698-1-ira.weiny@intel.co= m/T/#u Suggested-by: Ira Weiny Suggested-by: Fabio M. De Francesco Signed-off-by: Zhao Liu Reviewed-by: Ira Weiny --- Suggested by credits: Ira: Referred to his task document and suggestions about using memcpy_from_page() directly. Fabio: Referred to his boiler plate commit message. --- drivers/gpu/drm/i915/gt/uc/intel_uc_fw.c | 5 +---- 1 file changed, 1 insertion(+), 4 deletions(-) diff --git a/drivers/gpu/drm/i915/gt/uc/intel_uc_fw.c b/drivers/gpu/drm/i91= 5/gt/uc/intel_uc_fw.c index b91ad4aede1f..64d56f175d32 100644 --- a/drivers/gpu/drm/i915/gt/uc/intel_uc_fw.c +++ b/drivers/gpu/drm/i915/gt/uc/intel_uc_fw.c @@ -962,16 +962,13 @@ size_t intel_uc_fw_copy_rsa(struct intel_uc_fw *uc_fw= , void *dst, u32 max_len) =20 for_each_sgt_page(page, iter, uc_fw->obj->mm.pages) { u32 len =3D min_t(u32, size, PAGE_SIZE - offset); - void *vaddr; =20 if (idx > 0) { idx--; continue; } =20 - vaddr =3D kmap_atomic(page); - memcpy(dst, vaddr + offset, len); - kunmap_atomic(vaddr); + memcpy_from_page(dst, page, offset, len); =20 offset =3D 0; dst +=3D len; --=20 2.34.1 From nobody Tue Apr 7 12:47:35 2026 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id EDD74C4332F for ; Mon, 17 Oct 2022 09:33:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231373AbiJQJdZ (ORCPT ); Mon, 17 Oct 2022 05:33:25 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43454 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231354AbiJQJdR (ORCPT ); Mon, 17 Oct 2022 05:33:17 -0400 Received: from mga14.intel.com (mga14.intel.com [192.55.52.115]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 86D905A808 for ; Mon, 17 Oct 2022 02:32:56 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1665999176; x=1697535176; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=0Ch/gzI1CiEltsWtZiZ1vnI7GDsumr0SEFm747ErScU=; b=jgCItgeC1R/Zp94KyKUhQnOWheZ9NvWIOckwNkWRHkjNznPwLqAZsUb6 MEZtEmJhJNDS2ooI4yuMy3552pwR2w0zCOKFAGQF3Tgba+HmIP943UcIp pRsLLJsbPNNuwFAlO4blrePUBbUS4WaVAG4gCs2BiIL3Ks44SMPMXVxoO An5oaMC49vxjX+zh3Kk1BQPdJn+WJvOeoxG/y5elWau+SnSCGBJTy/6vn Dv3jZTT3ENkzf62GaMbrZAC9qbQkD1fla//f6X7HfJ9CRNtilZw/dduyz gAyQSxCLx7Fkf9IxoW7wi2hpRBK8KgYDXKpNdNBQsi/2hjEnQWwpXRS6r w==; X-IronPort-AV: E=McAfee;i="6500,9779,10502"; a="305741641" X-IronPort-AV: E=Sophos;i="5.95,191,1661842800"; d="scan'208";a="305741641" Received: from fmsmga003.fm.intel.com ([10.253.24.29]) by fmsmga103.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 17 Oct 2022 02:32:56 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6500,9779,10502"; a="717431333" X-IronPort-AV: E=Sophos;i="5.95,191,1661842800"; d="scan'208";a="717431333" Received: from liuzhao-optiplex-7080.sh.intel.com ([10.239.160.132]) by FMSMGA003.fm.intel.com with ESMTP; 17 Oct 2022 02:32:52 -0700 From: Zhao Liu To: Jani Nikula , Joonas Lahtinen , Rodrigo Vivi , Tvrtko Ursulin , David Airlie , Daniel Vetter , Matthew Auld , =?UTF-8?q?Thomas=20Hellstr=C3=B6m?= , Nirmoy Das , Maarten Lankhorst , Chris Wilson , =?UTF-8?q?Christian=20K=C3=B6nig?= , intel-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org Cc: Ira Weiny , "Fabio M . De Francesco" , Zhenyu Wang , Zhao Liu , Dave Hansen Subject: [PATCH 8/9] drm/i915: Use kmap_local_page() in i915_cmd_parser.c Date: Mon, 17 Oct 2022 17:37:24 +0800 Message-Id: <20221017093726.2070674-9-zhao1.liu@linux.intel.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20221017093726.2070674-1-zhao1.liu@linux.intel.com> References: <20221017093726.2070674-1-zhao1.liu@linux.intel.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" From: Zhao Liu The use of kmap_atomic() is being deprecated in favor of kmap_local_page()[1]. The main difference between atomic and local mappings is that local mappings doesn't disable page faults or preemption. There're 2 reasons why function copy_batch() doesn't need to disable pagefaults and preemption for mapping: 1. The flush operation is safe for CPU hotplug when preemption is not disabled. In i915_cmd_parser.c, the function copy_batch() calls drm_clflush_virt_range() to use CLFLUSHOPT or WBINVD to flush. Since CLFLUSHOPT is global on x86 and WBINVD is called on each cpu in drm_clflush_virt_range(), the flush operation is global and any issue with cpu's being added or removed can be handled safely. 2. Any context switch caused by preemption or sleep (pagefault may cause sleep) doesn't affect the validity of local mapping. Therefore, copy_batch() is a function where the use of kmap_local_page() in place of kmap_atomic() is correctly suited. Convert the calls of kmap_atomic() / kunmap_atomic() to kmap_local_page() / kunmap_local(). [1]: https://lore.kernel.org/all/20220813220034.806698-1-ira.weiny@intel.com Suggested-by: Dave Hansen Suggested-by: Ira Weiny Suggested-by: Fabio M. De Francesco Signed-off-by: Zhao Liu --- Suggested by credits: Dave: Referred to his explanation about cache flush. Ira: Referred to his task document, review comments and explanation about cache flush. Fabio: Referred to his boiler plate commit message. --- drivers/gpu/drm/i915/i915_cmd_parser.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/i915/i915_cmd_parser.c b/drivers/gpu/drm/i915/= i915_cmd_parser.c index f93e6122f247..1a56000d7476 100644 --- a/drivers/gpu/drm/i915/i915_cmd_parser.c +++ b/drivers/gpu/drm/i915/i915_cmd_parser.c @@ -1211,11 +1211,11 @@ static u32 *copy_batch(struct drm_i915_gem_object *= dst_obj, for (n =3D offset >> PAGE_SHIFT; remain; n++) { int len =3D min(remain, PAGE_SIZE - x); =20 - src =3D kmap_atomic(i915_gem_object_get_page(src_obj, n)); + src =3D kmap_local_page(i915_gem_object_get_page(src_obj, n)); if (src_needs_clflush) drm_clflush_virt_range(src + x, len); memcpy(ptr, src + x, len); - kunmap_atomic(src); + kunmap_local(src); =20 ptr +=3D len; remain -=3D len; --=20 2.34.1 From nobody Tue Apr 7 12:47:35 2026 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 503CCC433FE for ; Mon, 17 Oct 2022 09:33:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230021AbiJQJdz (ORCPT ); Mon, 17 Oct 2022 05:33:55 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44184 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231301AbiJQJdV (ORCPT ); Mon, 17 Oct 2022 05:33:21 -0400 Received: from mga14.intel.com (mga14.intel.com [192.55.52.115]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C108F5AA16 for ; Mon, 17 Oct 2022 02:33:00 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1665999180; x=1697535180; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=JEcLb6X6ZbdiyJg/wD23ZbxE1Ia5HJhKof7dQaZ62+0=; b=lT5vhBu0RWIm+b3ZiSz3PqoK3NAJ9LbXO07/zGGeOyfITp6qXxlVMqHT tfjx7pqEZTLLq4oZpwVvuR5vmQbH2UwL1ETqCACeuZY2/QIqYBtzFEMc1 Ac0TIbMbd9580A8rq4O1LP7dOkaOGSq0Hlh8dY4wxTCG/Q632TyxbNWBq rgx0tOfr/BMK9KjxX8CSZyn258clRIB37iaJzjORXNDsgoKzYPI60jX3r cu44bFr5sE81JMgi8VUu7S3ULEPzP6Qpi2QFqwgGWO1SjhsdY91bqZrF6 Lxu6QfKmuaNtvtJehdmLrhIGldBeZ2i/YFxDt+d55spof+UaINeqXbTKb g==; X-IronPort-AV: E=McAfee;i="6500,9779,10502"; a="305741659" X-IronPort-AV: E=Sophos;i="5.95,191,1661842800"; d="scan'208";a="305741659" Received: from fmsmga003.fm.intel.com ([10.253.24.29]) by fmsmga103.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 17 Oct 2022 02:33:00 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6500,9779,10502"; a="717431340" X-IronPort-AV: E=Sophos;i="5.95,191,1661842800"; d="scan'208";a="717431340" Received: from liuzhao-optiplex-7080.sh.intel.com ([10.239.160.132]) by FMSMGA003.fm.intel.com with ESMTP; 17 Oct 2022 02:32:56 -0700 From: Zhao Liu To: Jani Nikula , Joonas Lahtinen , Rodrigo Vivi , Tvrtko Ursulin , David Airlie , Daniel Vetter , Matthew Auld , =?UTF-8?q?Thomas=20Hellstr=C3=B6m?= , Nirmoy Das , Maarten Lankhorst , Chris Wilson , =?UTF-8?q?Christian=20K=C3=B6nig?= , intel-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org Cc: Ira Weiny , "Fabio M . De Francesco" , Zhenyu Wang , Zhao Liu Subject: [PATCH 9/9] drm/i915: Use kmap_local_page() in gem/i915_gem_execbuffer.c Date: Mon, 17 Oct 2022 17:37:25 +0800 Message-Id: <20221017093726.2070674-10-zhao1.liu@linux.intel.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20221017093726.2070674-1-zhao1.liu@linux.intel.com> References: <20221017093726.2070674-1-zhao1.liu@linux.intel.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" From: Zhao Liu The use of kmap_atomic() is being deprecated in favor of kmap_local_page()[1]. The main difference between atomic and local mappings is that local mappings doesn't disable page faults or preemption. In i915_gem_execbuffer.c, eb->reloc_cache.vaddr is mapped by kmap_atomic() in eb_relocate_entry(), and is unmapped by kunmap_atomic() in reloc_cache_reset(). And this mapping/unmapping occurs in two places: one is in eb_relocate_vma(), and another is in eb_relocate_vma_slow(). The function eb_relocate_vma() or eb_relocate_vma_slow() doesn't need to disable pagefaults and preemption during the above mapping/ unmapping. So it can simply use kmap_local_page() / kunmap_local() that can instead do the mapping / unmapping regardless of the context. Convert the calls of kmap_atomic() / kunmap_atomic() to kmap_local_page() / kunmap_local(). [1]: https://lore.kernel.org/all/20220813220034.806698-1-ira.weiny@intel.com Suggested-by: Ira Weiny Signed-off-by: Zhao Liu --- drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff --git a/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c b/drivers/gpu/d= rm/i915/gem/i915_gem_execbuffer.c index 845023c14eb3..8263d4e6620a 100644 --- a/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c +++ b/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c @@ -1110,7 +1110,7 @@ static void reloc_cache_unmap(struct reloc_cache *cac= he) =20 vaddr =3D unmask_page(cache->vaddr); if (cache->vaddr & KMAP) - kunmap_atomic(vaddr); + kunmap_local(vaddr); else io_mapping_unmap_atomic((void __iomem *)vaddr); } @@ -1126,7 +1126,7 @@ static void reloc_cache_remap(struct reloc_cache *cac= he, if (cache->vaddr & KMAP) { struct page *page =3D i915_gem_object_get_page(obj, cache->page); =20 - vaddr =3D kmap_atomic(page); + vaddr =3D kmap_local_page(page); cache->vaddr =3D unmask_flags(cache->vaddr) | (unsigned long)vaddr; } else { @@ -1156,7 +1156,7 @@ static void reloc_cache_reset(struct reloc_cache *cac= he, struct i915_execbuffer if (cache->vaddr & CLFLUSH_AFTER) mb(); =20 - kunmap_atomic(vaddr); + kunmap_local(vaddr); i915_gem_object_finish_access(obj); } else { struct i915_ggtt *ggtt =3D cache_to_ggtt(cache); @@ -1188,7 +1188,7 @@ static void *reloc_kmap(struct drm_i915_gem_object *o= bj, struct page *page; =20 if (cache->vaddr) { - kunmap_atomic(unmask_page(cache->vaddr)); + kunmap_local(unmask_page(cache->vaddr)); } else { unsigned int flushes; int err; @@ -1210,7 +1210,7 @@ static void *reloc_kmap(struct drm_i915_gem_object *o= bj, if (!obj->mm.dirty) set_page_dirty(page); =20 - vaddr =3D kmap_atomic(page); + vaddr =3D kmap_local_page(page); cache->vaddr =3D unmask_flags(cache->vaddr) | (unsigned long)vaddr; cache->page =3D pageno; =20 --=20 2.34.1 From nobody Tue Apr 7 12:47:35 2026 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2F6D1C4332F for ; Mon, 17 Oct 2022 09:34:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230380AbiJQJd6 (ORCPT ); Mon, 17 Oct 2022 05:33:58 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43452 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231394AbiJQJdV (ORCPT ); Mon, 17 Oct 2022 05:33:21 -0400 Received: from mga14.intel.com (mga14.intel.com [192.55.52.115]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 04FBB5AA1C for ; Mon, 17 Oct 2022 02:33:04 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1665999184; x=1697535184; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=7DWIlBvRBPlI7C3mshKcaEtH4mYWv0nITpy5+EZ8lew=; b=AFAu9yFKR+W+9Ub/PyHTDF3LQvZxFE451L5OmLOUmEIaRlsXl5IOb1T0 e+aLuZ/InWvpWHAaRqbwwkDJXoIzPICHdfYs+Qw0zI6yhiBXVX3aTq4F+ kNqvWzkqtxxuesIjr2VGzPDjJrFaLEUnZ2RgkcCrDxiPahz5cNUSpEDoP ZReu8PubTpojKbW4wI5C9BdDVsa37BPmXAPgverJo41z0lnLZSw0PRmc9 B36sIo2Rj92vpm/D/fxxBAcU9F13Dwq0RrZRoBgEkzxMivQNcM+ufvlJT oJXiGIxLwAcFlTxkulnxUt34afzqI36YriKvlcROs8oDnk30kPfW0TSsc w==; X-IronPort-AV: E=McAfee;i="6500,9779,10502"; a="305741669" X-IronPort-AV: E=Sophos;i="5.95,191,1661842800"; d="scan'208";a="305741669" Received: from fmsmga003.fm.intel.com ([10.253.24.29]) by fmsmga103.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 17 Oct 2022 02:33:04 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6500,9779,10502"; a="717431351" X-IronPort-AV: E=Sophos;i="5.95,191,1661842800"; d="scan'208";a="717431351" Received: from liuzhao-optiplex-7080.sh.intel.com ([10.239.160.132]) by FMSMGA003.fm.intel.com with ESMTP; 17 Oct 2022 02:33:00 -0700 From: Zhao Liu To: Jani Nikula , Joonas Lahtinen , Rodrigo Vivi , Tvrtko Ursulin , David Airlie , Daniel Vetter , Matthew Auld , =?UTF-8?q?Thomas=20Hellstr=C3=B6m?= , Nirmoy Das , Maarten Lankhorst , Chris Wilson , =?UTF-8?q?Christian=20K=C3=B6nig?= , intel-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org Cc: Ira Weiny , "Fabio M . De Francesco" , Zhenyu Wang , Zhao Liu Subject: [PATCH v3] x86/hyperv: Replace kmap() with kmap_local_page() Date: Mon, 17 Oct 2022 17:37:26 +0800 Message-Id: <20221017093726.2070674-11-zhao1.liu@linux.intel.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20221017093726.2070674-1-zhao1.liu@linux.intel.com> References: <20221017093726.2070674-1-zhao1.liu@linux.intel.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" From: Zhao Liu kmap() is being deprecated in favor of kmap_local_page()[1]. There are two main problems with kmap(): (1) It comes with an overhead as m= apping space is restricted and protected by a global lock for synchronizati= on and (2) it also requires global TLB invalidation when the kmap's pool wr= aps and it might block when the mapping space is fully utilized until a slo= t becomes available. With kmap_local_page() the mappings are per thread, CPU local, can take pag= e faults, and can be called from any context (including interrupts). It is faster than kmap() in kernels with HIGHMEM enabled. Furthermore, the = tasks can be preempted and, when they are scheduled to run again, the kerne= l virtual addresses are restored and are still valid. Since its use in hyperv/hv_init.c is safe, it should be preferred. Therefore, replace kmap() with kmap_local_page() in hyperv/hv_init.c. [1]: https://lore.kernel.org/all/20220813220034.806698-1-ira.weiny@intel.com Suggested-by: Ira Weiny Suggested-by: Fabio M. De Francesco Signed-off-by: Zhao Liu --- Suggested by credits. Ira: Referred to his task documentation and review comments. Fabio: Stole some of his boiler plate commit message. --- Changelog: v2: - Fix wrong incoming parameters in kunmap_local(); - Add Fabio as suggester since I quoted his commit message. --- arch/x86/hyperv/hv_init.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/x86/hyperv/hv_init.c b/arch/x86/hyperv/hv_init.c index 3de6d8b53367..72fe46eb183f 100644 --- a/arch/x86/hyperv/hv_init.c +++ b/arch/x86/hyperv/hv_init.c @@ -459,13 +459,13 @@ void __init hyperv_init(void) wrmsrl(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64); pg =3D vmalloc_to_page(hv_hypercall_pg); - dst =3D kmap(pg); + dst =3D kmap_local_page(pg); src =3D memremap(hypercall_msr.guest_physical_address << PA= GE_SHIFT, PAGE_SIZE, MEMREMAP_WB); BUG_ON(!(src && dst)); memcpy(dst, src, HV_HYP_PAGE_SIZE); memunmap(src); - kunmap(pg); + kunmap_local(dst); } else { hypercall_msr.guest_physical_address =3D vmalloc_to_pfn(hv_= hypercall_pg); wrmsrl(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64); -- 2.34.1