From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1) server-digest SHA256) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 741E860A260E for ; Tue, 10 Nov 2026 20:59:58 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=I3ciHHmw Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id D7A6110E37E; Tue, 10 Nov 2026 20:59:52 +0000 (UTC) Received: from sea.source.kernel.org (sea.source.kernel.org [172.234.252.31]) by gabe.freedesktop.org (Postfix) with ESMTPS id 8A9DD10EDCB for ; Tue, 10 Nov 2026 20:59:46 +0000 (UTC) Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) by sea.source.kernel.org (Postfix) with ESMTP id 2278444E70; Tue, 10 Nov 2026 20:59:46 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id D9DE31F008A4; Tue, 10 Nov 2026 20:59:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1794344386; bh=yj+5m3KmopzQkMK0Jm8pRRJElMTMawKOB8MBt/3Wy+E=; h=From:Subject:Reply-To:To:In-Reply-To:References:Date; b=I3ciHHmw9CY/goOk/N59evBzxCPqrhUYKie3yc2jsBMC+jHKcbFLf70kZX4HxRcqB 9CzPtrZTpCNC3Knx+JdEZ+cNULN2z5R538DQesK7S+gBIw3SUbqTrv5zrMeL3h+3if qvg3R/abiVmU3pOdWtUzPLuqKuCFJtbXq1wp4xD1nEHUkvR7RnAJiTBP0mL6ZtXXRV IVwD3jivF9i2Rov7rrNqaqojigJL3GMhXsEpsxSouhz+1zzsLig5Xj/sS6rBGGyt41 ZWGTXfLIlIN6ccV+nk1JgEteaCFY3vOZpFRb02RWeWU6z/BUkpgmz/7z8iiYBEV8Zq IIlUOYjjr5xwA== Message-ID: From: sashiko-bot@kernel.org Subject: Re: [PATCH V3] accel/amdxdna: Drop dma-buf wrapping for ubuf To: "Lizhi Hou" , dri-devel@lists.freedesktop.org In-Reply-To: <20261110202644.3270432-1-lizhi.hou@amd.com> References: <20261110202644.3270432-1-lizhi.hou@amd.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Date: Tue, 10 Nov 2026 20:59:45 +0000 X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: sashiko-reviews@lists.linux.dev Sender: "dri-devel" X-Spam-Status: No, score=-10.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=4.0.1 X-Spam-Checker-Version: SpamAssassin 4.0.1 (2024-03-26) on aws-us-west-2-korg-listserv-alma10-1 X-Archived-By: Thank you for your contribution! Sashiko AI review found 2 potential issues to consider: - [Medium] accel/amdxdna: amdxdna_ubuf_hmm_register() accepts VM_PFNMAP and VM_IO VMAs - [Medium] accel/amdxdna: missing is_private_bo() check in amdxdna_flush_bo() -- commit 1d6d9a5c2780dbf488fd71cbc00a82dc1ec39b14 Author: Lizhi Hou accel/amdxdna: Drop dma-buf wrapping for ubuf This commit converts ubuf buffer objects from imported dma-buf objects to private DRM GEM objects and tracks their userspace virtual addresses with HMM instead of long-term page pinning. > diff --git a/drivers/accel/amdxdna/amdxdna_gem.c b/drivers/accel/amdxdna/= amdxdna_gem.c > index ffe12a722dfea..a94195ea4e045 100644 > --- a/drivers/accel/amdxdna/amdxdna_gem.c > +++ b/drivers/accel/amdxdna/amdxdna_gem.c [ ... ] > @@ -1364,7 +1370,7 @@ static int amdxdna_bo_pin(struct amdxdna_gem_obj *a= bo) > struct amdxdna_dev *xdna =3D to_xdna_dev(to_gobj(abo)->dev); > int ret; > =20 > - if (is_import_bo(abo)) > + if (is_import_bo(abo) || is_private_bo(abo)) > return 0; > =20 > ret =3D drm_gem_shmem_pin(&abo->base); > @@ -1377,7 +1383,7 @@ static void amdxdna_bo_unpin(struct amdxdna_gem_obj= *abo) > { > struct amdxdna_dev *xdna =3D to_xdna_dev(to_gobj(abo)->dev); > =20 > - if (is_import_bo(abo)) > + if (is_import_bo(abo) || is_private_bo(abo)) > return; > =20 > drm_gem_shmem_unpin(&abo->base); [Severity: Medium] Should amdxdna_flush_bo() also check is_private_bo(abo) alongside is_import_bo(abo)? Previously, ubuf BOs were imported via amdxdna_gem_prime_import(), so is_import_bo(abo) was true and amdxdna_flush_bo() returned -EOPNOTSUPP. Because ubuf BOs are now initialized with drm_gem_private_object_init() and only set abo->private_buffer, DRM_IOCTL_AMDXDNA_SYNC_BO on a ubuf BO misses the early return in amdxdna_flush_bo(): drivers/accel/amdxdna/amdxdna_gem.c:amdxdna_flush_bo() { if (is_import_bo(abo)) return -EOPNOTSUPP; ... if (amdxdna_gem_vmap(abo)) drm_clflush_virt_range(amdxdna_gem_vmap(abo) + offset, size); else if (abo->base.pages) drm_clflush_pages(abo->base.pages, abo->mem.size >> PAGE_SHIFT); else return -EINVAL; } As a result, syncing a ubuf BO returns 0 when size is 0, or falls through to amdxdna_gem_vmap(abo) and abo->base.pages and returns -EINVAL instead of -EOPNOTSUPP. [ ... ] > diff --git a/drivers/accel/amdxdna/amdxdna_ubuf.c b/drivers/accel/amdxdna= /amdxdna_ubuf.c > index 0e0cd69cd1fbf..a5e202fbc72b9 100644 > --- a/drivers/accel/amdxdna/amdxdna_ubuf.c > +++ b/drivers/accel/amdxdna/amdxdna_ubuf.c > @@ -6,182 +6,127 @@ [ ... ] > +static int amdxdna_ubuf_hmm_register(struct amdxdna_client *client, > + struct amdxdna_gem_obj *abo, > + struct amdxdna_drm_va_entry *va_ent) > { > - struct amdxdna_ubuf_priv *ubuf =3D attach->dmabuf->priv; > - struct sg_table *sg; > + struct vm_area_struct *vma; > int ret; > =20 > - sg =3D kzalloc_obj(*sg); > - if (!sg) > - return ERR_PTR(-ENOMEM); > - > - ret =3D sg_alloc_table_from_pages(sg, ubuf->pages, ubuf->nr_pages, 0, > - ubuf->nr_pages << PAGE_SHIFT, GFP_KERNEL); > - if (ret) > - goto err_free_sg; > + mmap_write_lock(client->mm); > + vma =3D find_vma(client->mm, va_ent->vaddr); > + if (!vma || vma->vm_start > va_ent->vaddr || > + vma->vm_end - va_ent->vaddr < va_ent->len) { > + ret =3D -EINVAL; > + goto unlock; > + } > =20 > - ret =3D dma_map_sgtable(attach->dev, sg, direction, 0); > - if (ret) > - goto err_free_table; > + ret =3D amdxdna_hmm_register(abo, vma, va_ent->vaddr - vma->vm_start, v= a_ent->len); > + if (!ret && !(vma->vm_flags & (VM_PFNMAP | VM_IO))) > + amdxdna_mark_map_invalid(abo); [Severity: Medium] Should amdxdna_ubuf_hmm_register() reject VMAs with VM_PFNMAP or VM_IO instead of skipping amdxdna_mark_map_invalid(abo)? Previously, amdxdna_get_ubuf() called pin_user_pages_fast(), which rejected VM_PFNMAP and VM_IO mappings. Skipping amdxdna_mark_map_invalid(abo) leaves abo->mem.map_invalid false, so amdxdna_umap_stale() always returns false and amdxdna_gem_umap_populate() never faults in the range on command submission; if a VM_PFNMAP or VM_IO VMA passed to DRM_IOCTL_AMDXDNA_CREATE_BO is lazily populated or has its PTEs zapped, the device will hit IOMMU page faults when accessing the PASID address. --=20 Sashiko AI review =C2=B7 https://sashiko.dev/#/patchset/20261110202644.3270= 432-1-lizhi.hou@amd.com?part=3D1