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 E8B942576E for ; Sat, 12 Sep 2026 04:25:04 +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=1789187106; cv=none; b=DXCr9p8IfgjkVL3hCy36aJ8njHOz1Zy0zHCcdVszBePQqBwpuoCfP+Aa+lQ5oLlrhpsaZcjBEanJ/nIWbWCPMhaqdRpuOGMC8Nk4zvxBC/hmeZXo35iGGVohyj96PZjB357CRHGPtUuxLeSAPqeDp60ZY9KHU32Rvm0kI3lWjHA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789187106; c=relaxed/simple; bh=SmvdaJdHjccHn3fm6k8hW5KRkIkJM+J+coardOZYz2s=; h=Date:From:To:Cc:Subject:Message-Id:In-Reply-To:References: Mime-Version:Content-Type; b=St9EnjalyEVEY0u2TqmulsHR4Ylkkem+6aemtEwipI/P7nA3x2uB7grMeXv4PKeuuDjrNLd2uFt7NHG8pBtgO0AfscbWvJFnf4po0eafSIqMUS9O8kw87MnT5jlybokTfYyyPrEtDetRu1C1wZj62o4JG9YW2oKVHeeTm8BxYC4= 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=BwBMXooH; 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="BwBMXooH" Received: by smtp.kernel.org (Postfix) with ESMTPSA id C86D01F000FF; Sat, 12 Sep 2026 04:25:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux-foundation.org; s=korg; t=1789187104; bh=WD2psr2yzjyCJK4w/2X5moNA7VDH939yz28Da2OB/Wg=; h=Date:From:To:Cc:Subject:In-Reply-To:References; b=BwBMXooHh/FNWX+eVvSFWRbzYe6GxMeInSjLfY6+Uh9LrW8QyR6o6r0+nH+La9maz b4H+drJ6+Gacit9buekB7BqVmjK0WJWa7BwKTcv7DOFGdtVXy8KSOZdZNjfMHdgOMB jgsKImFGNu+YneeknvNigWDwqdNFh/vSUHU/NFhc= Date: Fri, 11 Sep 2026 21:25:03 -0700 From: Andrew Morton To: Gregory Price Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, kernel-team@meta.com, liam@infradead.org, ljs@kernel.org, david@kernel.org, vbabka@kernel.org, jannh@google.com, ziy@nvidia.com, matthew.brost@intel.com, joshua.hahnjy@gmail.com, rakie.kim@sk.com, byungchul@sk.com, ying.huang@linux.alibaba.com, apopple@nvidia.com, peterx@redhat.com, jgg@ziepe.ca, sashiko-bot Subject: Re: [PATCH v2 0/2] mm: stop calling pmd_folio() on special PMDs Message-Id: <20260911212503.bcf8461db17ebbf51233826a@linux-foundation.org> In-Reply-To: <20260912034833.2952750-1-gourry@gourry.net> References: <20260912034833.2952750-1-gourry@gourry.net> X-Mailer: Sylpheed 3.8.0beta1 (GTK+ 2.24.33; x86_64-pc-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=US-ASCII Content-Transfer-Encoding: 7bit On Fri, 11 Sep 2026 23:48:31 -0400 Gregory Price wrote: > Reproducer > ========== > > No hardware needed. An out of tree module stands in for the drivers above: > three misc devices, each with a ->huge_fault calling vmf_insert_pfn_pmd(), > plus VM_HUGEPAGE so the fault path takes the PMD branch. I take it there's no known way of triggering this in current mainline?