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=-8.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 04F20C433E0 for ; Wed, 20 Jan 2021 09:05:16 +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 91BA222CE3 for ; Wed, 20 Jan 2021 09:05:15 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 91BA222CE3 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=ffwll.ch Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=amd-gfx-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 2EA25899BC; Wed, 20 Jan 2021 09:05:15 +0000 (UTC) Received: from mail-wm1-x333.google.com (mail-wm1-x333.google.com [IPv6:2a00:1450:4864:20::333]) by gabe.freedesktop.org (Postfix) with ESMTPS id D7DBA89823 for ; Wed, 20 Jan 2021 09:05:04 +0000 (UTC) Received: by mail-wm1-x333.google.com with SMTP id j18so2120196wmi.3 for ; Wed, 20 Jan 2021 01:05:04 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ffwll.ch; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=i4nqYNmBtc+ZihQZqVRLoQMrxMqI2N0HIeOSWshZ7jc=; b=U/ppbP6Nu6vLLKyyFl+NzyzWY7RFIHWDpf4tH5fP6rKIXH5IuYUKKTXb0NbEQYbeDR sCexJmPX8usTA1XxyVIArUqlwsdHlhOtm/oqHpSOG9HhI/kJhzc0DGHLTpnlNhDTxHHN X2OFXYnuC95OyjXTQrpU4sUmd3t/mIoIfhqro= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=i4nqYNmBtc+ZihQZqVRLoQMrxMqI2N0HIeOSWshZ7jc=; b=tawLtTXaKpkwJvaq4kMNuD+rCKWJQl+k2tSaB4Id71ZbVsjricGGMEbRpZpcgnO296 CtWPe0Vq6LulZTt6VKfLMLVVPYEk/bGXCcDExVt+clG3JJlujcZNsSSD9BWA7a+Ps2/D 0uLHO5+y3Yc+8e3nUfoJfunmsjBDB+ryE28OT3FpegSMC2O10PoW13UQEMdoNMXuHAuf jRb8I2oAbKR46gQWPHvJrW7AJuHInUpPKsK4ORONHgOxtknBQCxTalj/kFtqZqQq7xFc AnUJ+LD4payqgVQTVzqLRiELtCL0PnX6/EWFegn3zHlAYawbp4VckylWtFkkac5QoTf/ +8AQ== X-Gm-Message-State: AOAM533uSyU1F9peBdcGRGPuyeJn4XlNCHcydt1InsmtOzFe0kO2nO8u 5w0z83foIkcU3NNO1A/5UymnkA== X-Google-Smtp-Source: ABdhPJzaoAIDcoN9osllhZVE9DZkeWRMi/QvJrh/Np3HvHw9pC3hjBkgYkl1A5tTR8/i5lND5RkBCw== X-Received: by 2002:a7b:c319:: with SMTP id k25mr3376185wmj.142.1611133503519; Wed, 20 Jan 2021 01:05:03 -0800 (PST) Received: from phenom.ffwll.local ([2a02:168:57f4:0:efd0:b9e5:5ae6:c2fa]) by smtp.gmail.com with ESMTPSA id r10sm2688648wmd.15.2021.01.20.01.05.02 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 20 Jan 2021 01:05:02 -0800 (PST) Date: Wed, 20 Jan 2021 10:05:00 +0100 From: Daniel Vetter To: Andrey Grodzovsky Subject: Re: [PATCH v4 00/14] RFC Support hot device unplug in amdgpu Message-ID: References: <1611003683-3534-1-git-send-email-andrey.grodzovsky@amd.com> <755e7c8a-5bd7-6414-8141-249a1ba5a865@amd.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <755e7c8a-5bd7-6414-8141-249a1ba5a865@amd.com> X-Operating-System: Linux phenom 5.7.0-1-amd64 X-BeenThere: amd-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Discussion list for AMD gfx List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Rob Herring , Christian =?iso-8859-1?Q?K=F6nig?= , dri-devel , "Anholt, Eric" , Pekka Paalanen , amd-gfx list , Daniel Vetter , Greg KH , Alex Deucher , Qiang Yu , "Wentland, Harry" , Lucas Stach Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: amd-gfx-bounces@lists.freedesktop.org Sender: "amd-gfx" On Tue, Jan 19, 2021 at 01:18:15PM -0500, Andrey Grodzovsky wrote: > > On 1/19/21 1:08 PM, Daniel Vetter wrote: > > On Tue, Jan 19, 2021 at 6:31 PM Andrey Grodzovsky > > wrote: > > > > > > On 1/19/21 9:16 AM, Daniel Vetter wrote: > > > > On Mon, Jan 18, 2021 at 04:01:09PM -0500, Andrey Grodzovsky wrote: > > > > > Until now extracting a card either by physical extraction (e.g. eGPU with > > > > > thunderbolt connection or by emulation through syfs -> /sys/bus/pci/devices/device_id/remove) > > > > > would cause random crashes in user apps. The random crashes in apps were > > > > > mostly due to the app having mapped a device backed BO into its address > > > > > space was still trying to access the BO while the backing device was gone. > > > > > To answer this first problem Christian suggested to fix the handling of mapped > > > > > memory in the clients when the device goes away by forcibly unmap all buffers the > > > > > user processes has by clearing their respective VMAs mapping the device BOs. > > > > > Then when the VMAs try to fill in the page tables again we check in the fault > > > > > handlerif the device is removed and if so, return an error. This will generate a > > > > > SIGBUS to the application which can then cleanly terminate.This indeed was done > > > > > but this in turn created a problem of kernel OOPs were the OOPSes were due to the > > > > > fact that while the app was terminating because of the SIGBUSit would trigger use > > > > > after free in the driver by calling to accesses device structures that were already > > > > > released from the pci remove sequence.This was handled by introducing a 'flush' > > > > > sequence during device removal were we wait for drm file reference to drop to 0 > > > > > meaning all user clients directly using this device terminated. > > > > > > > > > > v2: > > > > > Based on discussions in the mailing list with Daniel and Pekka [1] and based on the document > > > > > produced by Pekka from those discussions [2] the whole approach with returning SIGBUS and > > > > > waiting for all user clients having CPU mapping of device BOs to die was dropped. > > > > > Instead as per the document suggestion the device structures are kept alive until > > > > > the last reference to the device is dropped by user client and in the meanwhile all existing and new CPU mappings of the BOs > > > > > belonging to the device directly or by dma-buf import are rerouted to per user > > > > > process dummy rw page.Also, I skipped the 'Requirements for KMS UAPI' section of [2] > > > > > since i am trying to get the minimal set of requirements that still give useful solution > > > > > to work and this is the'Requirements for Render and Cross-Device UAPI' section and so my > > > > > test case is removing a secondary device, which is render only and is not involved > > > > > in KMS. > > > > > > > > > > v3: > > > > > More updates following comments from v2 such as removing loop to find DRM file when rerouting > > > > > page faults to dummy page,getting rid of unnecessary sysfs handling refactoring and moving > > > > > prevention of GPU recovery post device unplug from amdgpu to scheduler layer. > > > > > On top of that added unplug support for the IOMMU enabled system. > > > > > > > > > > v4: > > > > > Drop last sysfs hack and use sysfs default attribute. > > > > > Guard against write accesses after device removal to avoid modifying released memory. > > > > > Update dummy pages handling to on demand allocation and release through drm managed framework. > > > > > Add return value to scheduler job TO handler (by Luben Tuikov) and use this in amdgpu for prevention > > > > > of GPU recovery post device unplug > > > > > Also rebase on top of drm-misc-mext instead of amd-staging-drm-next > > > > > > > > > > With these patches I am able to gracefully remove the secondary card using sysfs remove hook while glxgears > > > > > is running off of secondary card (DRI_PRIME=1) without kernel oopses or hangs and keep working > > > > > with the primary card or soft reset the device without hangs or oopses > > > > > > > > > > TODOs for followup work: > > > > > Convert AMDGPU code to use devm (for hw stuff) and drmm (for sw stuff and allocations) (Daniel) > > > > > Support plugging the secondary device back after unplug - currently still experiencing HW error on plugging back. > > > > > Add support for 'Requirements for KMS UAPI' section of [2] - unplugging primary, display connected card. > > > > > > > > > > [1] - Discussions during v3 of the patchset https://nam11.safelinks.protection.outlook.com/?url=https%3A%2F%2Fwww.spinics.net%2Flists%2Famd-gfx%2Fmsg55576.html&data=04%7C01%7CAndrey.Grodzovsky%40amd.com%7C9055ea164ca14a0cbce108d8bca53d37%7C3dd8961fe4884e608e11a82d994e183d%7C0%7C0%7C637466765176719365%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C1000&sdata=AqqeqmhF%2BZ1%2BRwMgtpmfoW1gtEnLGxiy3U5OMm%2BBqk8%3D&reserved=0 > > > > > [2] - drm/doc: device hot-unplug for userspace https://nam11.safelinks.protection.outlook.com/?url=https%3A%2F%2Fwww.spinics.net%2Flists%2Fdri-devel%2Fmsg259755.html&data=04%7C01%7CAndrey.Grodzovsky%40amd.com%7C9055ea164ca14a0cbce108d8bca53d37%7C3dd8961fe4884e608e11a82d994e183d%7C0%7C0%7C637466765176719365%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C1000&sdata=oHHyRtTMTNQAnkzptG0B8%2FeeniU1z2DSca8L4yCYJcE%3D&reserved=0 > > > > > [3] - Related gitlab ticket https://nam11.safelinks.protection.outlook.com/?url=https%3A%2F%2Fgitlab.freedesktop.org%2Fdrm%2Famd%2F-%2Fissues%2F1081&data=04%7C01%7CAndrey.Grodzovsky%40amd.com%7C9055ea164ca14a0cbce108d8bca53d37%7C3dd8961fe4884e608e11a82d994e183d%7C0%7C0%7C637466765176719365%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C1000&sdata=inKlV%2F5QIPw%2BhHvLM46X27%2Fcjr%2FXyhxmrC0xYXBhHuE%3D&reserved=0 > > > > btw have you tried this out with some of the igts we have? core_hotunplug > > > > is the one I'm thinking of. Might be worth to extend this for amdgpu > > > > specific stuff (like run some batches on it while hotunplugging). > > > No, I mostly used just running glxgears while testing which covers already > > > exported/imported dma-buf case and a few manually hacked tests in libdrm amdgpu > > > test suite > > > > > > > > > > Since there's so many corner cases we need to test here (shared dma-buf, > > > > shared dma_fence) I think it would make sense to have a shared testcase > > > > across drivers. > > > > > > Not familiar with IGT too much, is there an easy way to setup shared dma bufs > > > and fences > > > use cases there or you mean I need to add them now ? > > We do have test infrastructure for all of that, but the hotunplug test > > doesn't have that yet I think. > > > > > > Only specific thing would be some hooks to keep the gpu > > > > busy in some fashion while we yank the driver. > > > > > > Do you mean like staring X and some active rendering on top (like glxgears) > > > automatically from within IGT ? > > Nope, igt is meant to be bare metal testing so you don't have to drag > > the entire winsys around (which in a wayland world, is not really good > > for driver testing anyway, since everything is different). We use this > > for our pre-merge ci for drm/i915. > > > So i keep it busy by X/glxgers which is manual operation. What you suggest > then is some client within IGT which opens the device and starts submitting jobs > (which is much like what libdrm amdgpu tests already do) ? And this > part is the amdgou specific code I just need to port from libdrm to here ? Yup. For i915 tests we have an entire library already for small workloads, including some that just spin forever (useful for reset testing and could also come handy for unload testing). -Daniel > > Andrey > > > > > > > > But just to get it started > > > > you can throw in entirely amdgpu specific subtests and just share some of > > > > the test code. > > > > -Daniel > > > > > > Im general, I wasn't aware of this test suite and looks like it does what i test > > > among other stuff. > > > I will definitely try to run with it although the rescan part will not work as > > > plugging > > > the device back is in my TODO list and not part of the scope for this patchset > > > and so I will > > > probably comment the re-scan section out while testing. > > amd gem has been using libdrm-amd thus far iirc, but for things like > > this I think it'd be worth to at least consider switching. Display > > team has already started to use some of the test and contribute stuff > > (I think the VRR testcase is from amd). > > -Daniel > > > > > Andrey > > > > > > > > > > > Andrey Grodzovsky (13): > > > > > drm/ttm: Remap all page faults to per process dummy page. > > > > > drm: Unamp the entire device address space on device unplug > > > > > drm/ttm: Expose ttm_tt_unpopulate for driver use > > > > > drm/sched: Cancel and flush all oustatdning jobs before finish. > > > > > drm/amdgpu: Split amdgpu_device_fini into early and late > > > > > drm/amdgpu: Add early fini callback > > > > > drm/amdgpu: Register IOMMU topology notifier per device. > > > > > drm/amdgpu: Fix a bunch of sdma code crash post device unplug > > > > > drm/amdgpu: Remap all page faults to per process dummy page. > > > > > dmr/amdgpu: Move some sysfs attrs creation to default_attr > > > > > drm/amdgpu: Guard against write accesses after device removal > > > > > drm/sched: Make timeout timer rearm conditional. > > > > > drm/amdgpu: Prevent any job recoveries after device is unplugged. > > > > > > > > > > Luben Tuikov (1): > > > > > drm/scheduler: Job timeout handler returns status > > > > > > > > > > drivers/gpu/drm/amd/amdgpu/amdgpu.h | 11 +- > > > > > drivers/gpu/drm/amd/amdgpu/amdgpu_atombios.c | 17 +-- > > > > > drivers/gpu/drm/amd/amdgpu/amdgpu_device.c | 149 ++++++++++++++++++++-- > > > > > drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c | 20 ++- > > > > > drivers/gpu/drm/amd/amdgpu/amdgpu_fence.c | 15 ++- > > > > > drivers/gpu/drm/amd/amdgpu/amdgpu_gart.c | 2 +- > > > > > drivers/gpu/drm/amd/amdgpu/amdgpu_gart.h | 1 + > > > > > drivers/gpu/drm/amd/amdgpu/amdgpu_gmc.c | 9 ++ > > > > > drivers/gpu/drm/amd/amdgpu/amdgpu_gtt_mgr.c | 25 ++-- > > > > > drivers/gpu/drm/amd/amdgpu/amdgpu_irq.c | 26 ++-- > > > > > drivers/gpu/drm/amd/amdgpu/amdgpu_irq.h | 3 +- > > > > > drivers/gpu/drm/amd/amdgpu/amdgpu_job.c | 19 ++- > > > > > drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c | 12 +- > > > > > drivers/gpu/drm/amd/amdgpu/amdgpu_object.c | 10 ++ > > > > > drivers/gpu/drm/amd/amdgpu/amdgpu_object.h | 2 + > > > > > drivers/gpu/drm/amd/amdgpu/amdgpu_psp.c | 53 +++++--- > > > > > drivers/gpu/drm/amd/amdgpu/amdgpu_psp.h | 3 + > > > > > drivers/gpu/drm/amd/amdgpu/amdgpu_ras.c | 1 + > > > > > drivers/gpu/drm/amd/amdgpu/amdgpu_ring.c | 70 ++++++++++ > > > > > drivers/gpu/drm/amd/amdgpu/amdgpu_ring.h | 52 +------- > > > > > drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c | 21 ++- > > > > > drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c | 8 +- > > > > > drivers/gpu/drm/amd/amdgpu/amdgpu_vram_mgr.c | 14 +- > > > > > drivers/gpu/drm/amd/amdgpu/cik_ih.c | 2 +- > > > > > drivers/gpu/drm/amd/amdgpu/cz_ih.c | 2 +- > > > > > drivers/gpu/drm/amd/amdgpu/iceland_ih.c | 2 +- > > > > > drivers/gpu/drm/amd/amdgpu/navi10_ih.c | 2 +- > > > > > drivers/gpu/drm/amd/amdgpu/psp_v11_0.c | 16 +-- > > > > > drivers/gpu/drm/amd/amdgpu/psp_v12_0.c | 8 +- > > > > > drivers/gpu/drm/amd/amdgpu/psp_v3_1.c | 8 +- > > > > > drivers/gpu/drm/amd/amdgpu/si_ih.c | 2 +- > > > > > drivers/gpu/drm/amd/amdgpu/tonga_ih.c | 2 +- > > > > > drivers/gpu/drm/amd/amdgpu/vega10_ih.c | 2 +- > > > > > drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 12 +- > > > > > drivers/gpu/drm/amd/include/amd_shared.h | 2 + > > > > > drivers/gpu/drm/drm_drv.c | 3 + > > > > > drivers/gpu/drm/etnaviv/etnaviv_sched.c | 10 +- > > > > > drivers/gpu/drm/lima/lima_sched.c | 4 +- > > > > > drivers/gpu/drm/panfrost/panfrost_job.c | 9 +- > > > > > drivers/gpu/drm/scheduler/sched_main.c | 18 ++- > > > > > drivers/gpu/drm/ttm/ttm_bo_vm.c | 82 +++++++++++- > > > > > drivers/gpu/drm/ttm/ttm_tt.c | 1 + > > > > > drivers/gpu/drm/v3d/v3d_sched.c | 32 ++--- > > > > > include/drm/gpu_scheduler.h | 17 ++- > > > > > include/drm/ttm/ttm_bo_api.h | 2 + > > > > > 45 files changed, 583 insertions(+), 198 deletions(-) > > > > > > > > > > -- > > > > > 2.7.4 > > > > > > > > > -- Daniel Vetter Software Engineer, Intel Corporation http://blog.ffwll.ch _______________________________________________ amd-gfx mailing list amd-gfx@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/amd-gfx