From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 55F8D1FAC54; Mon, 21 Jul 2025 16:27:34 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1753115254; cv=none; b=ia8DVwyonJwbdzHM8zaxlK1WONeHU4Id5l38RbtUCDw2R2Y4k1+5bub/2wVDaF+vdoqVxnjs6766W2xwoCmuX910KaI4zo0z3VuQ1PD8wao/zVl1YCvbgR+OuP9bd+IxIRkUx8D88KS3nqdoiuXYCO5HsB2YhsNlF7G+PIiNMpE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1753115254; c=relaxed/simple; bh=b0d+bnRoA9TIC8iQXqP3VrctHSad9OvpokIx7T7GPTs=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=RbQZULa/wJd9tWCjqi0ntDoSm7cTTK6kkP9zqEqKoYAl4VoQOwuupLXKT/XrRpgqV+WdA/xooPLdjqWK7CkeZnhjEs8nAyrhaIbfj7LqqmAblCbDiSwRTG4T6CplStd2bq2OToPZgpajdPWiZoUCjFO/ybhVHBCjN6e834eNUX8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=i9bt/BhT; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="i9bt/BhT" Received: by smtp.kernel.org (Postfix) with ESMTPSA id C450BC4CEF6; Mon, 21 Jul 2025 16:27:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1753115253; bh=b0d+bnRoA9TIC8iQXqP3VrctHSad9OvpokIx7T7GPTs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=i9bt/BhTZN+41Lq9LCvFOIR5ZZSCs2DbpJXIwv61jUMIpd1GCfnlp5eHR/j97RDh9 bCrVRxkBRWseQIScsZjcqUL3MOwb/lo9b7Jvr6yZjiH6Q2VVb2466OKbq8svQUTX1Z APRZcHtr6dzLWj1vsrDp3pBj6KuhMNqXzBPJ7NZC3w99nAGAaLOp/tt0RZ4DW2YhsW PH/ptO/FOSDiAv6ZwKBXG9oi9OioH5xPBNXoMtcW2IU8YF2eZ2ap5mBB8IC3YIufMt JcMKVRaJkrHIClEaKrICLFu9xqWcrBYBv5WwdjNPsyKP+PbveTo254P6EnIm79cgOD p6iN2zwmVH3yA== From: SeongJae Park To: Lorenzo Stoakes Cc: SeongJae Park , Andrew Morton , David Hildenbrand , Zi Yan , Baolin Wang , "Liam R . Howlett" , Nico Pache , Ryan Roberts , Dev Jain , Barry Song , Jonathan Corbet , linux-mm@kvack.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] docs: update THP documentation to clarify sysfs "never" setting Date: Mon, 21 Jul 2025 09:27:31 -0700 Message-Id: <20250721162731.9822-1-sj@kernel.org> X-Mailer: git-send-email 2.39.5 In-Reply-To: <20250721155530.75944-1-lorenzo.stoakes@oracle.com> References: Precedence: bulk X-Mailing-List: linux-doc@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit On Mon, 21 Jul 2025 16:55:30 +0100 Lorenzo Stoakes wrote: > Rather confusingly, setting all Transparent Huge Page sysfs settings to > "never" does not in fact result in THP being globally disabled. > > Rather, it results in khugepaged being disabled, but one can still obtain > THP pages using madvise(..., MADV_COLLAPSE). > > This is something that has remained poorly documented for some time, and it > is likely the received wisdom of most users of THP that never does, in > fact, mean never. > > It is therefore important to highlight, very clearly, that this is not the > ase. case? > > Signed-off-by: Lorenzo Stoakes Acked-by: SeongJae Park Thanks, SJ [...]