From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from bali.collaboradmins.com (bali.collaboradmins.com [148.251.105.195]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 9E8EA38AC99 for ; Fri, 19 Jun 2026 12:59:13 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=148.251.105.195 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781873954; cv=none; b=qG2L+qV4hkGPakS+cgJ0atmM1AWp1VORJenTDawHOgvtWK3kSiRwXlDNNEJ8scIXIlh/VVpDKbVGfurfN1Ukh0q2fpAW59hp6VWOVlE8h79n771N/4HneKNrGGa3ngieo3QPuAxHg/CwiPTv61Rb+yQ+CUFxCNj7CM5NmabzEKA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781873954; c=relaxed/simple; bh=0p2u53FG5VhGy9JxQbC3htNun4nfs2U9CZoW16vvUhk=; h=Date:From:To:Cc:Subject:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=R4ha7sD8fEvEoFGcUdeRzNClKQHx3IiIeSyqqZy4Ywx8bp764MwD5ZqhGHJIRGK8t5pSo+LtUx9fuNodPBHTaN6wwwjk4y/k09lr17ezWVldG25ugi6G4DX+y1vbhqCBb0eD8Q4xVMWXRYBqiHPOAVeRcypRaSoksM5oCZ7QWgo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=collabora.com; spf=pass smtp.mailfrom=collabora.com; dkim=pass (2048-bit key) header.d=collabora.com header.i=@collabora.com header.b=do3eS6QO; arc=none smtp.client-ip=148.251.105.195 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=collabora.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=collabora.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=collabora.com header.i=@collabora.com header.b="do3eS6QO" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=collabora.com; s=mail; t=1781873951; bh=0p2u53FG5VhGy9JxQbC3htNun4nfs2U9CZoW16vvUhk=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=do3eS6QOan733pVoPUt1sbnqDh2EBS32wMaIrBm0VpcInOyIurLbLNz4WgBjivuQy Fjr/R+dSCrEN18MAlEGksE+vS+mn7kr39DoopxHlgu2T6n5KqDWZg8SGYOBTGNNOtT qYd6JIFrORaIZ0Oci1/UyoHmnWyoS6FqaceuXGeanlVSaXF+cYrCKV2I8D5Wk3Bfku brl9j0G168dBB+NDlvpSqdNiYv+4KIP1n1V6Ou4RtfOTDZX5AowcstIFcMSotX2azO NiQhSmsimwrkplo/5pqL63Aq6LgTZqsLl6qd0+WQsrSoYBFK8pEzw8kEDYBO1xGJSz kN4u8Wd4RbWnw== Received: from fedora-2.home (unknown [100.64.0.11]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange ECDHE (prime256v1) server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) (Authenticated sender: bbrezillon) by bali.collaboradmins.com (Postfix) with ESMTPSA id 734CE17E05DE; Fri, 19 Jun 2026 14:59:11 +0200 (CEST) Date: Fri, 19 Jun 2026 14:59:06 +0200 From: Boris Brezillon To: =?UTF-8?B?QWRyacOhbg==?= Larumbe Cc: Steven Price , Liviu Dudau , Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , David Airlie , Simona Vetter , dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v2 1/2] drm/panthor: Add vm_bind region with kbo range overlap check Message-ID: <20260619145906.3b78b357@fedora-2.home> In-Reply-To: <20260619-vm_bind_checks-v2-1-b51abab35f71@collabora.com> References: <20260619-vm_bind_checks-v2-0-b51abab35f71@collabora.com> <20260619-vm_bind_checks-v2-1-b51abab35f71@collabora.com> Organization: Collabora X-Mailer: Claws Mail 4.4.0 (GTK 3.24.52; x86_64-redhat-linux-gnu) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable On Fri, 19 Jun 2026 13:41:22 +0100 Adri=C3=A1n Larumbe wrote: > When a VM is created, caller has to specify the range of the address space > carve-out set aside for mapping kernel BO's. That means vm_bind mappings = of > UM-exposed BO's should not intersect with that region, but at the moment > we're not checking this. >=20 > At first, I thought of giving these values to drm_gpuvm_init() through its > reserve_{offset, range} arguments, but it turns out that is meant for VM > address spans that are not managed through the usual drm_gpuvm split/merge > circuit, so storing the end of the user VA range at VM creation time and > doing a quick check in the vm_bind ioctl path was the simplest workaround. >=20 > Signed-off-by: Adri=C3=A1n Larumbe Ah, we need a Fixes tag here. > --- > drivers/gpu/drm/panthor/panthor_mmu.c | 9 +++++++++ > 1 file changed, 9 insertions(+) >=20 > diff --git a/drivers/gpu/drm/panthor/panthor_mmu.c b/drivers/gpu/drm/pant= hor/panthor_mmu.c > index 31cc57029c12..a8de4fe6b231 100644 > --- a/drivers/gpu/drm/panthor/panthor_mmu.c > +++ b/drivers/gpu/drm/panthor/panthor_mmu.c > @@ -310,6 +310,9 @@ struct panthor_vm { > u64 end; > } kernel_auto_va; > =20 > + /** @user_va_end: Last VA in the address range VM users can map objects= against. */ > + u64 user_va_end; > + > /** @as: Address space related fields. */ > struct { > /** > @@ -2893,6 +2896,8 @@ panthor_vm_create(struct panthor_device *ptdev, boo= l for_mcu, > va_range =3D full_va_range; > } > =20 > + vm->user_va_end =3D kernel_va_start - 1; > + > mutex_init(&vm->mm_lock); > drm_mm_init(&vm->mm, kernel_va_start, kernel_va_size); > vm->kernel_auto_va.start =3D auto_kernel_va_start; > @@ -2981,6 +2986,10 @@ panthor_vm_bind_prepare_op_ctx(struct drm_file *fi= le, > if (!IS_ALIGNED(op->va | op->size | op->bo_offset, vm_pgsz)) > return -EINVAL; > =20 > + /* We don't allow mappings that overlap with kbo's reserved range */ > + if (op->va + op->size > vm->user_va_end) > + return -EINVAL; > + > switch (op->flags & DRM_PANTHOR_VM_BIND_OP_TYPE_MASK) { > case DRM_PANTHOR_VM_BIND_OP_TYPE_MAP: > if (!(op->flags & DRM_PANTHOR_VM_BIND_OP_MAP_SPARSE)) { >=20