From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 14E07326951 for ; Mon, 6 Jul 2026 10:57:57 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.140.110.172 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783335480; cv=none; b=HQ5Wyy4IISr+gP4lNl552DRJm2K5I3aRrO2+7LmetUuJtE0rV3Lt5aY1d/jKydmoXr2UGK6q+S0k54aZWpEzW3jZShcH4Uvajqi/I8IZFSWlTMWV59e7/Rm1bqwnxvVlD/PxrQLXqXjVGep4K7PXffkgWjb2eLT1yuFIWF8Ia4c= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783335480; c=relaxed/simple; bh=bRHd/dTPazO61cnkNoD2dOdp95aZDc+DylqAFQVHz7A=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=qNQEfh1TMjAdCKzbY3AjUFLWoJSuvl2UPlqjwCRPa4rMmYctvfi2nUPOTMzuG+x9O0dP23ekKa2SUAL+WSihzDHP04qOesV8SUwJELpCnhQrCKFgCHqFjwwpoZjVCWzOkpbRhvjDdSNJBCoOkPz+A1dGBVCD3uNnk1H9DwfEaIs= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com; spf=pass smtp.mailfrom=arm.com; dkim=pass (1024-bit key) header.d=arm.com header.i=@arm.com header.b=WR71N0Sd; arc=none smtp.client-ip=217.140.110.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=arm.com header.i=@arm.com header.b="WR71N0Sd" Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id ED62C32AD for ; Mon, 6 Jul 2026 03:57:52 -0700 (PDT) Received: from [192.168.0.1] (usa-sjc-imap-foss1.foss.arm.com [10.121.207.14]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 176603F85F for ; Mon, 6 Jul 2026 03:57:56 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=arm.com; s=foss; t=1783335477; bh=bRHd/dTPazO61cnkNoD2dOdp95aZDc+DylqAFQVHz7A=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=WR71N0Sdol6N9PCllHJTx/a68vZ7pwOsRNShe/psC+A/NCjz9aB2S/yMAYyeGLyEx c5RR/ZTD/SOpcqljNH6m0VNZC3XGqzvN0BSIeQoINTIYcDKZAfdtRfxmXWpOr3MQwC NB5VRx5gME/pADO1nny1XKTnZa/QSb3eoT1ViWEE= Date: Mon, 6 Jul 2026 11:57:45 +0100 From: Liviu Dudau To: =?utf-8?Q?Adri=C3=A1n?= Larumbe Cc: Boris Brezillon , Steven Price , Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , David Airlie , Simona Vetter , Heiko Stuebner , Grant Likely , dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v4 2/3] drm/panthor: Add vm_bind region with kbo range overlap check Message-ID: References: <20260704-vm_bind_checks-v4-0-4705b6ca9f8a@collabora.com> <20260704-vm_bind_checks-v4-2-4705b6ca9f8a@collabora.com> 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-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20260704-vm_bind_checks-v4-2-4705b6ca9f8a@collabora.com> On Sat, Jul 04, 2026 at 05:46:45AM +0100, Adrián 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. > > 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. > > Fixes: tag and reference the relevant sparse binding support commit. > Fixes: 647810ec2476 ("drm/panthor: Add the MMU/VM logical block") > Reviewed-by: Boris Brezillon > Signed-off-by: Adrián Larumbe Reviewed-by: Liviu Dudau Best regards, Liviu > --- > drivers/gpu/drm/panthor/panthor_mmu.c | 9 +++++++++ > 1 file changed, 9 insertions(+) > > diff --git a/drivers/gpu/drm/panthor/panthor_mmu.c b/drivers/gpu/drm/panthor/panthor_mmu.c > index 163231c1703d..662a2c13b467 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; > > + /** @user_va_range: Upper boundary of VAs VM users can map objects against. */ > + u64 user_va_range; > + > /** @as: Address space related fields. */ > struct { > /** > @@ -2893,6 +2896,8 @@ panthor_vm_create(struct panthor_device *ptdev, bool for_mcu, > va_range = full_va_range; > } > > + vm->user_va_range = kernel_va_start; > + > mutex_init(&vm->mm_lock); > drm_mm_init(&vm->mm, kernel_va_start, kernel_va_size); > vm->kernel_auto_va.start = auto_kernel_va_start; > @@ -2985,6 +2990,10 @@ panthor_vm_bind_prepare_op_ctx(struct drm_file *file, > if (check_add_overflow(op->va, op->size, &end)) > return -EINVAL; > > + /* We don't allow mappings that overlap with kbo's reserved range */ > + if (end > vm->user_va_range) > + 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)) { > > -- > 2.55.0 > -- ==================== | I would like to | | fix the world, | | but they're not | | giving me the | \ source code! / --------------- ¯\_(ツ)_/¯