From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 E9EA02DB7BE; Sat, 11 Jul 2026 05:48:35 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783748917; cv=none; b=o0qhbtm23gtBCm4kFZk3ZDH1gRVDzNFPYjdnRtZobapVz7u1AijXLmYqw3z4pgJyV2yUCf8dwJYRVceStt3Q0O5r4Tno/ZRLLYlbg8f4vQ9a/ROaGdsvtTUeEq8KjeVUWJ8CJZjnjWohs3wW2+sOU7byTrXOsW9HFDF/TP3m8pU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783748917; c=relaxed/simple; bh=2X3u/rhMdoK2ZSzI5yRlLbKzVLTeEAk7NfzAxOZxq8M=; h=Date:From:To:Cc:Subject:Message-Id:In-Reply-To:References: Mime-Version:Content-Type; b=Svv3aPSGkD1Q0veLIwbSj3XAS1SgUWDr/DbneYWlZzhh1Co2O27I0E6kX2O2A9cCmRfRSlYfNoWlNeGPKRTbRCY4UH97zZeT38wQppzri+A9lT+hpx8GhYVtMw4R1bJWpqbqPFwVIYdQ1gCdzXUTz1Ap32OFjcVG1oyIc2UD9vI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b=zxP6H3RU; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b="zxP6H3RU" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 40B1C1F000E9; Sat, 11 Jul 2026 05:48:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux-foundation.org; s=korg; t=1783748915; bh=/bm56TdW2Rt1TzYZP4AwroZ1H/akE8N7PaZmAo9v49o=; h=Date:From:To:Cc:Subject:In-Reply-To:References; b=zxP6H3RUmBd6ihlhUQIdRJzfv+dWAy7/NIa1aujz+UJUigwYO9G60/3Bm1HoqfjnX DZhiti+OpHf6AgYSszNldBtjYCKgg5QG6160LxG4/45mDd4arD7V/RUmAhgcW9bWTx E9/cf5f5XfN6+ulL7h4VwT+i3BR5zKS6NdueS7go= Date: Fri, 10 Jul 2026 22:48:33 -0700 From: Andrew Morton To: Stanislav Kinsburskii Cc: airlied@gmail.com, akhilesh@ee.iitb.ac.in, corbet@lwn.net, dakr@kernel.org, david@kernel.org, decui@microsoft.com, haiyangz@microsoft.com, jgg@ziepe.ca, kees@kernel.org, kys@microsoft.com, leon@kernel.org, liam@infradead.org, lizhi.hou@amd.com, ljs@kernel.org, longli@microsoft.com, lyude@redhat.com, maarten.lankhorst@linux.intel.com, mamin506@gmail.com, mhocko@suse.com, mripard@kernel.org, nouveau@lists.freedesktop.org, ogabbay@kernel.org, oleg@redhat.com, rppt@kernel.org, shuah@kernel.org, simona@ffwll.ch, skhan@linuxfoundation.org, surenb@google.com, tzimmermann@suse.de, vbabka@kernel.org, wei.liu@kernel.org, dri-devel@lists.freedesktop.org, linux-mm@kvack.org, linux-doc@vger.kernel.org, linux-hyperv@vger.kernel.org, linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-rdma@vger.kernel.org Subject: Re: [PATCH v8 5/8] drm/nouveau: Use hmm_range_fault_unlocked_timeout() for SVM faults Message-Id: <20260710224833.9caf2a0a9906f0515e326a45@linux-foundation.org> In-Reply-To: References: <178371866223.900500.12312667138651735591.stgit@skinsburskii> <178371881847.900500.8789369230260725500.stgit@skinsburskii> <20260710151222.ddb35eab9c81a8720491464a@linux-foundation.org> X-Mailer: Sylpheed 3.8.0beta1 (GTK+ 2.24.33; x86_64-pc-linux-gnu) Precedence: bulk X-Mailing-List: linux-doc@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit On Fri, 10 Jul 2026 20:16:35 -0700 Stanislav Kinsburskii wrote: > On Fri, Jul 10, 2026 at 03:12:22PM -0700, Andrew Morton wrote: > > On Fri, 10 Jul 2026 14:26:58 -0700 Stanislav Kinsburskii wrote: > > > > > @@ -683,15 +683,11 @@ static int nouveau_range_fault(struct nouveau_svmm *svmm, > > > goto out; > > > } > > > > > > - range.notifier_seq = mmu_interval_read_begin(range.notifier); > > > - mmap_read_lock(mm); > > > - ret = hmm_range_fault(&range); > > > - mmap_read_unlock(mm); > > > - if (ret) { > > > - if (ret == -EBUSY) > > > - continue; > > > + ret = hmm_range_fault_unlocked_timeout(&range, > > > + max(timeout - jiffies, > > > + 1L)); > > > > "1UL" here? I'd have expected min() to warn, as it likes to do. > > I'm not sure... The "timeout - jiffies" can become negative. > Won't 1UL convert both of them to "UL" and thus make the comparison > overflow? `timeout' and `jiffies' are both unsigned long.