From nobody Sun Apr 19 12:15:23 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 58AF1C43334 for ; Fri, 1 Jul 2022 09:04:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232823AbiGAJEB (ORCPT ); Fri, 1 Jul 2022 05:04:01 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47380 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234914AbiGAJD5 (ORCPT ); Fri, 1 Jul 2022 05:03:57 -0400 Received: from madras.collabora.co.uk (madras.collabora.co.uk [46.235.227.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 24EC52FFE9; Fri, 1 Jul 2022 02:03:56 -0700 (PDT) Received: from dimapc.. (109-252-118-164.nat.spd-mgts.ru [109.252.118.164]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) (Authenticated sender: dmitry.osipenko) by madras.collabora.co.uk (Postfix) with ESMTPSA id A1DA66601974; Fri, 1 Jul 2022 10:03:53 +0100 (BST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=collabora.com; s=mail; t=1656666234; bh=7x6AJ+nAU7oVPHACGhPnUxGYHzyBq1CqfYXDnLu1/Bc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=MK6CbYPvW2XF1+ZGXNwvo9sH2iUyYhJ+MgxlhHthbBw8kxQaSpaxK0FD0byY0AdQT PiPzgUq/ifqmEvz1nu747iKfiZOJqEEjm9e/CREelUszS7gTh3DlFvRkKRIlc78Ib3 ffQ32n/buSTGHVwK2ONGJ4EMPZ7Psq6EO18yXrrZA5Lf4508+wVgmlik1z0YQ56jwB 654izyNPDU2PAyPWZdnrIIn0u4efZU1RqxKAosAgQWLTbSl8PsPzXORzP7hCL9AqG7 az9/ywI+O310Un1G0+VqqHm9+GXommhFgU9S2tsiAoJPYq/7QVIDREN2cij/l5xumJ x37iMvg7etmDg== From: Dmitry Osipenko To: David Airlie , Gerd Hoffmann , Gurchetan Singh , Chia-I Wu , Daniel Vetter , Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , Emil Velikov , =?UTF-8?q?Christian=20K=C3=B6nig?= , =?UTF-8?q?Thomas=20Hellstr=C3=B6m?= Cc: dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, Dmitry Osipenko , linux-tegra@vger.kernel.org, kernel@collabora.com, virtualization@lists.linux-foundation.org Subject: [PATCH v8 1/2] drm/gem: Properly annotate WW context on drm_gem_lock_reservations() error Date: Fri, 1 Jul 2022 12:02:39 +0300 Message-Id: <20220701090240.1896131-2-dmitry.osipenko@collabora.com> X-Mailer: git-send-email 2.36.1 In-Reply-To: <20220701090240.1896131-1-dmitry.osipenko@collabora.com> References: <20220701090240.1896131-1-dmitry.osipenko@collabora.com> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Use ww_acquire_fini() in the error code paths. Otherwise lockdep thinks that lock is held when lock's memory is freed after the drm_gem_lock_reservations() error. The ww_acquire_context needs to be annotated as "released", which fixes the noisy "WARNING: held lock freed!" splat of VirtIO-GPU driver with CONFIG_DEBUG_MUTEXES=3Dy and enabled lockde= p. Cc: stable@vger.kernel.org Fixes: 7edc3e3b975b5 ("drm: Add helpers for locking an array of BO reservat= ions.") Reviewed-by: Thomas Hellstr=C3=B6m Signed-off-by: Dmitry Osipenko Reviewed-by: Christian K=C3=B6nig --- drivers/gpu/drm/drm_gem.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/drm_gem.c b/drivers/gpu/drm/drm_gem.c index eb0c2d041f13..86d670c71286 100644 --- a/drivers/gpu/drm/drm_gem.c +++ b/drivers/gpu/drm/drm_gem.c @@ -1226,7 +1226,7 @@ drm_gem_lock_reservations(struct drm_gem_object **obj= s, int count, ret =3D dma_resv_lock_slow_interruptible(obj->resv, acquire_ctx); if (ret) { - ww_acquire_done(acquire_ctx); + ww_acquire_fini(acquire_ctx); return ret; } } @@ -1251,7 +1251,7 @@ drm_gem_lock_reservations(struct drm_gem_object **obj= s, int count, goto retry; } =20 - ww_acquire_done(acquire_ctx); + ww_acquire_fini(acquire_ctx); return ret; } } --=20 2.36.1 From nobody Sun Apr 19 12:15:23 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 0F3C1C43334 for ; Fri, 1 Jul 2022 09:04:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232788AbiGAJED (ORCPT ); Fri, 1 Jul 2022 05:04:03 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47408 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232975AbiGAJD6 (ORCPT ); Fri, 1 Jul 2022 05:03:58 -0400 Received: from madras.collabora.co.uk (madras.collabora.co.uk [46.235.227.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4FF452F005; Fri, 1 Jul 2022 02:03:57 -0700 (PDT) Received: from dimapc.. (109-252-118-164.nat.spd-mgts.ru [109.252.118.164]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) (Authenticated sender: dmitry.osipenko) by madras.collabora.co.uk (Postfix) with ESMTPSA id 085B26601995; Fri, 1 Jul 2022 10:03:54 +0100 (BST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=collabora.com; s=mail; t=1656666236; bh=RmdslR01N1MBAgH0PuAGwuMu+yy8zq6PlP6HQWG4wYg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=nHrfgsTuoRx8kOzlzVaWvklMsHeGG13lF79SxJNVQbDTriU/ELNxzpwemsXd/HJ6N tCgqYRHlBxMlkuqLP3wsvalsaUDzYtkehIk70F1HgELnpzz4FiOPyAtyY4y5UswUDN yAfyeqq7GMAYr/O9HKsoT/o1xbyv232TpRHF5nPetXV/bIdrNp6Q3ggZZvtcXuVttG Eg8Ad61hn6u3fNaXzZdHbQACed/6jgtaBhm55qJoAveWbHXi0f717HOAgAlTlD2G75 U7x206lJR1eFRFcfFdZcuxuWhuc+VzhdBI/8dKCJrNzOZ7u51CzPwOWOBQgagOvI9I rrmFFUrwntThg== From: Dmitry Osipenko To: David Airlie , Gerd Hoffmann , Gurchetan Singh , Chia-I Wu , Daniel Vetter , Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , Emil Velikov , =?UTF-8?q?Christian=20K=C3=B6nig?= , =?UTF-8?q?Thomas=20Hellstr=C3=B6m?= Cc: dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, Dmitry Osipenko , linux-tegra@vger.kernel.org, kernel@collabora.com, virtualization@lists.linux-foundation.org Subject: [PATCH v8 2/2] drm/gem: Don't map imported GEMs Date: Fri, 1 Jul 2022 12:02:40 +0300 Message-Id: <20220701090240.1896131-3-dmitry.osipenko@collabora.com> X-Mailer: git-send-email 2.36.1 In-Reply-To: <20220701090240.1896131-1-dmitry.osipenko@collabora.com> References: <20220701090240.1896131-1-dmitry.osipenko@collabora.com> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Drivers that use drm_gem_mmap() and drm_gem_mmap_obj() helpers don't handle imported dma-bufs properly, which results in mapping of something else than the imported dma-buf. On NVIDIA Tegra we get a hard lockup when userspace writes to the memory mapping of a dma-buf that was imported into Tegra's DRM GEM. Majority of DRM drivers prohibit mapping of the imported GEM objects. Mapping of imported GEMs require special care from userspace since it should sync dma-buf because mapping coherency of the exporter device may not match the DRM device. Let's prohibit the mapping for all DRM drivers for consistency. Suggested-by: Thomas Hellstr=C3=B6m Signed-off-by: Dmitry Osipenko --- drivers/gpu/drm/drm_gem.c | 4 ++++ drivers/gpu/drm/drm_gem_shmem_helper.c | 9 --------- 2 files changed, 4 insertions(+), 9 deletions(-) diff --git a/drivers/gpu/drm/drm_gem.c b/drivers/gpu/drm/drm_gem.c index 86d670c71286..fc9ec42fa0ab 100644 --- a/drivers/gpu/drm/drm_gem.c +++ b/drivers/gpu/drm/drm_gem.c @@ -1034,6 +1034,10 @@ int drm_gem_mmap_obj(struct drm_gem_object *obj, uns= igned long obj_size, { int ret; =20 + /* Don't allow imported objects to be mapped */ + if (obj->import_attach) + return -EINVAL; + /* Check for valid size. */ if (obj_size < vma->vm_end - vma->vm_start) return -EINVAL; diff --git a/drivers/gpu/drm/drm_gem_shmem_helper.c b/drivers/gpu/drm/drm_g= em_shmem_helper.c index 8ad0e02991ca..6190f5018986 100644 --- a/drivers/gpu/drm/drm_gem_shmem_helper.c +++ b/drivers/gpu/drm/drm_gem_shmem_helper.c @@ -609,17 +609,8 @@ EXPORT_SYMBOL_GPL(drm_gem_shmem_vm_ops); */ int drm_gem_shmem_mmap(struct drm_gem_shmem_object *shmem, struct vm_area_= struct *vma) { - struct drm_gem_object *obj =3D &shmem->base; int ret; =20 - if (obj->import_attach) { - /* Drop the reference drm_gem_mmap_obj() acquired.*/ - drm_gem_object_put(obj); - vma->vm_private_data =3D NULL; - - return dma_buf_mmap(obj->dma_buf, vma, 0); - } - ret =3D drm_gem_shmem_get_pages(shmem); if (ret) { drm_gem_vm_close(vma); --=20 2.36.1