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 X-Spam-Level: X-Spam-Status: No, score=-14.4 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,HK_RANDOM_FROM,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 31F8BC432BE for ; Thu, 29 Jul 2021 12:21:42 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id E0D4260C3F for ; Thu, 29 Jul 2021 12:21:41 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org E0D4260C3F Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.intel.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 49CDB6ED91; Thu, 29 Jul 2021 12:21:41 +0000 (UTC) Received: from mga09.intel.com (mga09.intel.com [134.134.136.24]) by gabe.freedesktop.org (Postfix) with ESMTPS id 8C7536ECDA; Thu, 29 Jul 2021 12:21:39 +0000 (UTC) X-IronPort-AV: E=McAfee;i="6200,9189,10059"; a="212860361" X-IronPort-AV: E=Sophos;i="5.84,278,1620716400"; d="scan'208";a="212860361" Received: from fmsmga002.fm.intel.com ([10.253.24.26]) by orsmga102.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 29 Jul 2021 05:21:38 -0700 X-IronPort-AV: E=Sophos;i="5.84,278,1620716400"; d="scan'208";a="518175752" Received: from eoghanru-mobl.ger.corp.intel.com (HELO [10.213.215.170]) ([10.213.215.170]) by fmsmga002-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 29 Jul 2021 05:21:36 -0700 Subject: Re: [PATCH 2/2] drm/i915: Use Transparent Hugepages when IOMMU is enabled To: Daniel Vetter References: <20210729111848.729888-1-tvrtko.ursulin@linux.intel.com> <20210729111848.729888-2-tvrtko.ursulin@linux.intel.com> From: Tvrtko Ursulin Organization: Intel Corporation UK Plc Message-ID: Date: Thu, 29 Jul 2021 13:21:34 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.11.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Tvrtko Ursulin , intel-gfx , dri-devel , Chris Wilson , Matthew Auld , Rodrigo Vivi , Eero Tamminen Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" On 29/07/2021 13:07, Daniel Vetter wrote: > On Thu, Jul 29, 2021 at 1:19 PM Tvrtko Ursulin > wrote: >> >> From: Tvrtko Ursulin >> >> Usage of Transparent Hugepages was disabled in 9987da4b5dcf >> ("drm/i915: Disable THP until we have a GPU read BW W/A"), but since it >> appears majority of performance regressions reported with an enabled IOMMU >> can be almost eliminated by turning them on, lets do that by adding a >> couple of Kconfig options. >> >> To err on the side of safety we keep the current default in cases where >> IOMMU is not active, and only when it is default to the "huge=within_size" >> mode. Although there probably would be wins to enable them throughout, >> more extensive testing across benchmarks and platforms would need to be >> done. >> >> With the patch and IOMMU enabled my local testing on a small Skylake part >> shows OglVSTangent regression being reduced from ~14% to ~2%. > > I guess the 14% regression is iommu disabled vs iommu enabled? Would > be good to clarify that. Should be clear from the first paragraph above - "...majority of performance regressions reported with an _enabled_ IOMMU can be almost eliminated...". > >> v2: >> * Add Kconfig dependency to transparent hugepages and some help text. > > Uh I'm really not a huge fan of Kconfig for everything, especially for > tuning stuff. Maybe if there's a need a module param for debugging, > but otherwise can't we just pick the right default? Kconfig is picking the right default so I do not see a problem by allowing override from a deep enough menu. But I also do not feel so strongly about bikeshedding this to no kconfig, or a module param, or whatever - there are votes for all three options already, as usual. Main problem I have is actually.. > And it very much sounds like the right default here is "enable it > unconditionally if we have iommu support". .. about this - who knows? I will remind you of a certain VLK-20150 which I thought was very important for going forward but was falling on deaf ears for years. As such I am waiting for Eero to come back and improvise some unofficial testing. It's extra bewildering to me given how we had the facility and then shut it down just like that. Regards, Tvrtko > -Daniel > >> * Move to helper for easier handling of kernel build options. >> >> References: b901bb89324a ("drm/i915/gemfs: enable THP") >> References: 9987da4b5dcf ("drm/i915: Disable THP until we have a GPU read BW W/A") >> References: https://gitlab.freedesktop.org/drm/intel/-/issues/430 >> Co-developed-by: Chris Wilson >> Signed-off-by: Chris Wilson >> Cc: Joonas Lahtinen >> Cc: Matthew Auld >> Cc: Eero Tamminen >> Cc: Tvrtko Ursulin >> Cc: Rodrigo Vivi >> Signed-off-by: Tvrtko Ursulin >> Reviewed-by: Rodrigo Vivi # v1 >> --- >> drivers/gpu/drm/i915/Kconfig.profile | 73 +++++++++++++++++++++++++++ >> drivers/gpu/drm/i915/gem/i915_gemfs.c | 27 ++++++++-- >> 2 files changed, 97 insertions(+), 3 deletions(-) >> >> diff --git a/drivers/gpu/drm/i915/Kconfig.profile b/drivers/gpu/drm/i915/Kconfig.profile >> index 39328567c200..d49ee794732f 100644 >> --- a/drivers/gpu/drm/i915/Kconfig.profile >> +++ b/drivers/gpu/drm/i915/Kconfig.profile >> @@ -119,3 +119,76 @@ config DRM_I915_TIMESLICE_DURATION >> /sys/class/drm/card?/engine/*/timeslice_duration_ms >> >> May be 0 to disable timeslicing. >> + >> +choice >> + prompt "Transparent Hugepage Support (native)" >> + default DRM_I915_THP_NATIVE_NEVER >> + depends on TRANSPARENT_HUGEPAGE >> + help >> + Select the preferred method for allocating from Transparent Hugepages >> + when IOMMU is not enabled. >> + >> + config DRM_I915_THP_NATIVE_NEVER >> + bool "Never" >> + help >> + Disable using THP for system memory allocations, individually >> + allocating each 4K chunk as a separate page. It is unlikely that such >> + individual allocations will return contiguous memory. >> + >> + config DRM_I915_THP_NATIVE_WITHIN >> + bool "Within size" >> + help >> + Allocate whole 2M superpages while those chunks do not exceed the >> + object size. The remainder of the object will be allocated from 4K >> + pages. No overallocation. >> + >> + config DRM_I915_THP_NATIVE_ALWAYS >> + bool "Always" >> + help >> + Allocate the whole object using 2M superpages, even if the object does >> + not require an exact number of superpages. >> + >> +endchoice >> + >> +config DRM_I915_THP_NATIVE >> + string >> + default "always" if DRM_I915_THP_NATIVE_ALWAYS >> + default "within_size" if DRM_I915_THP_NATIVE_WITHIN >> + default "never" if DRM_I915_THP_NATIVE_NEVER >> + >> +choice >> + prompt "Transparent Hugepage Support (IOMMU)" >> + default DRM_I915_THP_IOMMU_WITHIN if TRANSPARENT_HUGEPAGE=y >> + default DRM_I915_THP_IOMMU_NEVER if TRANSPARENT_HUGEPAGE=n >> + depends on TRANSPARENT_HUGEPAGE >> + help >> + Select the preferred method for allocating from Transparent Hugepages >> + with IOMMU active. >> + >> + config DRM_I915_THP_IOMMU_NEVER >> + bool "Never" >> + help >> + Disable using THP for system memory allocations, individually >> + allocating each 4K chunk as a separate page. It is unlikely that such >> + individual allocations will return contiguous memory. >> + >> + config DRM_I915_THP_IOMMU_WITHIN >> + bool "Within size" >> + help >> + Allocate whole 2M superpages while those chunks do not exceed the >> + object size. The remainder of the object will be allocated from 4K >> + pages. No overallocation. >> + >> + config DRM_I915_THP_IOMMU_ALWAYS >> + bool "Always" >> + help >> + Allocate the whole object using 2M superpages, even if the object does >> + not require an exact number of superpages. >> + >> +endchoice >> + >> +config DRM_I915_THP_IOMMU >> + string >> + default "always" if DRM_I915_THP_IOMMU_ALWAYS >> + default "within_size" if DRM_I915_THP_IOMMU_WITHIN >> + default "never" if DRM_I915_THP_IOMMU_NEVER >> diff --git a/drivers/gpu/drm/i915/gem/i915_gemfs.c b/drivers/gpu/drm/i915/gem/i915_gemfs.c >> index 5e6e8c91ab38..871cbfb02fdf 100644 >> --- a/drivers/gpu/drm/i915/gem/i915_gemfs.c >> +++ b/drivers/gpu/drm/i915/gem/i915_gemfs.c >> @@ -11,6 +11,26 @@ >> #include "i915_drv.h" >> #include "i915_gemfs.h" >> >> +#if defined(CONFIG_DRM_I915_THP_NATIVE) && defined(CONFIG_DRM_I915_THP_IOMMU) >> +static char *gemfd_mount_opts(struct drm_i915_private *i915) >> +{ >> + static char thp_native[] = "huge=" CONFIG_DRM_I915_THP_NATIVE; >> + static char thp_iommu[] = "huge=" CONFIG_DRM_I915_THP_IOMMU; >> + char *opts; >> + >> + opts = intel_vtd_active() ? thp_iommu : thp_native; >> + drm_info(&i915->drm, "Transparent Hugepage mode '%s'", opts); >> + >> + return opts; >> +} >> +#else >> +static char *gemfd_mount_opts(struct drm_i915_private *i915) >> +{ >> + return NULL; >> +} >> +#endif >> + >> + >> int i915_gemfs_init(struct drm_i915_private *i915) >> { >> struct file_system_type *type; >> @@ -26,10 +46,11 @@ int i915_gemfs_init(struct drm_i915_private *i915) >> * >> * One example, although it is probably better with a per-file >> * control, is selecting huge page allocations ("huge=within_size"). >> - * Currently unused due to bandwidth issues (slow reads) on Broadwell+. >> + * However, we only do so to offset the overhead of iommu lookups >> + * due to bandwidth issues (slow reads) on Broadwell+. >> */ >> - >> - gemfs = kern_mount(type); >> + gemfs = vfs_kern_mount(type, SB_KERNMOUNT, type->name, >> + gemfd_mount_opts(i915)); >> if (IS_ERR(gemfs)) >> return PTR_ERR(gemfs); >> >> -- >> 2.30.2 >> > > 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 X-Spam-Level: X-Spam-Status: No, score=-14.4 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,HK_RANDOM_FROM,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id BCA89C4338F for ; Thu, 29 Jul 2021 12:21:40 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id 7762B60C3F for ; Thu, 29 Jul 2021 12:21:40 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 7762B60C3F Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.intel.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 21AEF6ECDA; Thu, 29 Jul 2021 12:21:40 +0000 (UTC) Received: from mga09.intel.com (mga09.intel.com [134.134.136.24]) by gabe.freedesktop.org (Postfix) with ESMTPS id 8C7536ECDA; Thu, 29 Jul 2021 12:21:39 +0000 (UTC) X-IronPort-AV: E=McAfee;i="6200,9189,10059"; a="212860361" X-IronPort-AV: E=Sophos;i="5.84,278,1620716400"; d="scan'208";a="212860361" Received: from fmsmga002.fm.intel.com ([10.253.24.26]) by orsmga102.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 29 Jul 2021 05:21:38 -0700 X-IronPort-AV: E=Sophos;i="5.84,278,1620716400"; d="scan'208";a="518175752" Received: from eoghanru-mobl.ger.corp.intel.com (HELO [10.213.215.170]) ([10.213.215.170]) by fmsmga002-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 29 Jul 2021 05:21:36 -0700 To: Daniel Vetter References: <20210729111848.729888-1-tvrtko.ursulin@linux.intel.com> <20210729111848.729888-2-tvrtko.ursulin@linux.intel.com> From: Tvrtko Ursulin Organization: Intel Corporation UK Plc Message-ID: Date: Thu, 29 Jul 2021 13:21:34 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.11.0 MIME-Version: 1.0 In-Reply-To: Content-Language: en-US Subject: Re: [Intel-gfx] [PATCH 2/2] drm/i915: Use Transparent Hugepages when IOMMU is enabled 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: intel-gfx , dri-devel , Chris Wilson , Matthew Auld , Eero Tamminen Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="us-ascii"; Format="flowed" Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" On 29/07/2021 13:07, Daniel Vetter wrote: > On Thu, Jul 29, 2021 at 1:19 PM Tvrtko Ursulin > wrote: >> >> From: Tvrtko Ursulin >> >> Usage of Transparent Hugepages was disabled in 9987da4b5dcf >> ("drm/i915: Disable THP until we have a GPU read BW W/A"), but since it >> appears majority of performance regressions reported with an enabled IOMMU >> can be almost eliminated by turning them on, lets do that by adding a >> couple of Kconfig options. >> >> To err on the side of safety we keep the current default in cases where >> IOMMU is not active, and only when it is default to the "huge=within_size" >> mode. Although there probably would be wins to enable them throughout, >> more extensive testing across benchmarks and platforms would need to be >> done. >> >> With the patch and IOMMU enabled my local testing on a small Skylake part >> shows OglVSTangent regression being reduced from ~14% to ~2%. > > I guess the 14% regression is iommu disabled vs iommu enabled? Would > be good to clarify that. Should be clear from the first paragraph above - "...majority of performance regressions reported with an _enabled_ IOMMU can be almost eliminated...". > >> v2: >> * Add Kconfig dependency to transparent hugepages and some help text. > > Uh I'm really not a huge fan of Kconfig for everything, especially for > tuning stuff. Maybe if there's a need a module param for debugging, > but otherwise can't we just pick the right default? Kconfig is picking the right default so I do not see a problem by allowing override from a deep enough menu. But I also do not feel so strongly about bikeshedding this to no kconfig, or a module param, or whatever - there are votes for all three options already, as usual. Main problem I have is actually.. > And it very much sounds like the right default here is "enable it > unconditionally if we have iommu support". .. about this - who knows? I will remind you of a certain VLK-20150 which I thought was very important for going forward but was falling on deaf ears for years. As such I am waiting for Eero to come back and improvise some unofficial testing. It's extra bewildering to me given how we had the facility and then shut it down just like that. Regards, Tvrtko > -Daniel > >> * Move to helper for easier handling of kernel build options. >> >> References: b901bb89324a ("drm/i915/gemfs: enable THP") >> References: 9987da4b5dcf ("drm/i915: Disable THP until we have a GPU read BW W/A") >> References: https://gitlab.freedesktop.org/drm/intel/-/issues/430 >> Co-developed-by: Chris Wilson >> Signed-off-by: Chris Wilson >> Cc: Joonas Lahtinen >> Cc: Matthew Auld >> Cc: Eero Tamminen >> Cc: Tvrtko Ursulin >> Cc: Rodrigo Vivi >> Signed-off-by: Tvrtko Ursulin >> Reviewed-by: Rodrigo Vivi # v1 >> --- >> drivers/gpu/drm/i915/Kconfig.profile | 73 +++++++++++++++++++++++++++ >> drivers/gpu/drm/i915/gem/i915_gemfs.c | 27 ++++++++-- >> 2 files changed, 97 insertions(+), 3 deletions(-) >> >> diff --git a/drivers/gpu/drm/i915/Kconfig.profile b/drivers/gpu/drm/i915/Kconfig.profile >> index 39328567c200..d49ee794732f 100644 >> --- a/drivers/gpu/drm/i915/Kconfig.profile >> +++ b/drivers/gpu/drm/i915/Kconfig.profile >> @@ -119,3 +119,76 @@ config DRM_I915_TIMESLICE_DURATION >> /sys/class/drm/card?/engine/*/timeslice_duration_ms >> >> May be 0 to disable timeslicing. >> + >> +choice >> + prompt "Transparent Hugepage Support (native)" >> + default DRM_I915_THP_NATIVE_NEVER >> + depends on TRANSPARENT_HUGEPAGE >> + help >> + Select the preferred method for allocating from Transparent Hugepages >> + when IOMMU is not enabled. >> + >> + config DRM_I915_THP_NATIVE_NEVER >> + bool "Never" >> + help >> + Disable using THP for system memory allocations, individually >> + allocating each 4K chunk as a separate page. It is unlikely that such >> + individual allocations will return contiguous memory. >> + >> + config DRM_I915_THP_NATIVE_WITHIN >> + bool "Within size" >> + help >> + Allocate whole 2M superpages while those chunks do not exceed the >> + object size. The remainder of the object will be allocated from 4K >> + pages. No overallocation. >> + >> + config DRM_I915_THP_NATIVE_ALWAYS >> + bool "Always" >> + help >> + Allocate the whole object using 2M superpages, even if the object does >> + not require an exact number of superpages. >> + >> +endchoice >> + >> +config DRM_I915_THP_NATIVE >> + string >> + default "always" if DRM_I915_THP_NATIVE_ALWAYS >> + default "within_size" if DRM_I915_THP_NATIVE_WITHIN >> + default "never" if DRM_I915_THP_NATIVE_NEVER >> + >> +choice >> + prompt "Transparent Hugepage Support (IOMMU)" >> + default DRM_I915_THP_IOMMU_WITHIN if TRANSPARENT_HUGEPAGE=y >> + default DRM_I915_THP_IOMMU_NEVER if TRANSPARENT_HUGEPAGE=n >> + depends on TRANSPARENT_HUGEPAGE >> + help >> + Select the preferred method for allocating from Transparent Hugepages >> + with IOMMU active. >> + >> + config DRM_I915_THP_IOMMU_NEVER >> + bool "Never" >> + help >> + Disable using THP for system memory allocations, individually >> + allocating each 4K chunk as a separate page. It is unlikely that such >> + individual allocations will return contiguous memory. >> + >> + config DRM_I915_THP_IOMMU_WITHIN >> + bool "Within size" >> + help >> + Allocate whole 2M superpages while those chunks do not exceed the >> + object size. The remainder of the object will be allocated from 4K >> + pages. No overallocation. >> + >> + config DRM_I915_THP_IOMMU_ALWAYS >> + bool "Always" >> + help >> + Allocate the whole object using 2M superpages, even if the object does >> + not require an exact number of superpages. >> + >> +endchoice >> + >> +config DRM_I915_THP_IOMMU >> + string >> + default "always" if DRM_I915_THP_IOMMU_ALWAYS >> + default "within_size" if DRM_I915_THP_IOMMU_WITHIN >> + default "never" if DRM_I915_THP_IOMMU_NEVER >> diff --git a/drivers/gpu/drm/i915/gem/i915_gemfs.c b/drivers/gpu/drm/i915/gem/i915_gemfs.c >> index 5e6e8c91ab38..871cbfb02fdf 100644 >> --- a/drivers/gpu/drm/i915/gem/i915_gemfs.c >> +++ b/drivers/gpu/drm/i915/gem/i915_gemfs.c >> @@ -11,6 +11,26 @@ >> #include "i915_drv.h" >> #include "i915_gemfs.h" >> >> +#if defined(CONFIG_DRM_I915_THP_NATIVE) && defined(CONFIG_DRM_I915_THP_IOMMU) >> +static char *gemfd_mount_opts(struct drm_i915_private *i915) >> +{ >> + static char thp_native[] = "huge=" CONFIG_DRM_I915_THP_NATIVE; >> + static char thp_iommu[] = "huge=" CONFIG_DRM_I915_THP_IOMMU; >> + char *opts; >> + >> + opts = intel_vtd_active() ? thp_iommu : thp_native; >> + drm_info(&i915->drm, "Transparent Hugepage mode '%s'", opts); >> + >> + return opts; >> +} >> +#else >> +static char *gemfd_mount_opts(struct drm_i915_private *i915) >> +{ >> + return NULL; >> +} >> +#endif >> + >> + >> int i915_gemfs_init(struct drm_i915_private *i915) >> { >> struct file_system_type *type; >> @@ -26,10 +46,11 @@ int i915_gemfs_init(struct drm_i915_private *i915) >> * >> * One example, although it is probably better with a per-file >> * control, is selecting huge page allocations ("huge=within_size"). >> - * Currently unused due to bandwidth issues (slow reads) on Broadwell+. >> + * However, we only do so to offset the overhead of iommu lookups >> + * due to bandwidth issues (slow reads) on Broadwell+. >> */ >> - >> - gemfs = kern_mount(type); >> + gemfs = vfs_kern_mount(type, SB_KERNMOUNT, type->name, >> + gemfd_mount_opts(i915)); >> if (IS_ERR(gemfs)) >> return PTR_ERR(gemfs); >> >> -- >> 2.30.2 >> > > _______________________________________________ Intel-gfx mailing list Intel-gfx@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/intel-gfx