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 BDC7443B3EA; Thu, 24 Sep 2026 07:38:25 +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=1790235507; cv=none; b=UfUA7si2rtJnxBcnbJy5Yjzt7N0vb22QSVmIkZsZXaWUzuzVzKLiLs/a25q+iTXicbt7yqnriRAwqwbJfOupYy+W22htbvtVuSklvvRwjU36Ja+Oziwpcj6Yy+TypDSiaRClFvKfb96aBCx8x/RLnpWjluopIfLCnHcdtxsFZrw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790235507; c=relaxed/simple; bh=p6CmvTxdRWJaR85/x76jMBw0rw5S+UxLU9OMQSWKTns=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=gvwlAmclkbTBzLkQkacgcSmMWy1khKCLHoDVpXTzpiCHnrK9Ba5U84b5XQKzODUtbMQIa6GoObas2ohbE8tnz59g2XtgVMPGClQQ0/oOyCBA27FIZRZgydK7RYe3CzPavgB8WqMdGkVZhP6HyxRZ6bZDLie67mdK+HANuYX6xn8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=Qrg79Odc; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="Qrg79Odc" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 13F4F1F000FF; Thu, 24 Sep 2026 07:38:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1790235505; bh=syHUjeiyU6PAQHnSegmJU/Xn5fIogA7Zi7eAXuaZd0w=; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=Qrg79OdcGPfgl7yoXl3ptDh3IKF+UVtWixl4nCRdJqTGzJZ+s1Q/oDpS1tvP5TbmU NC/P3mvbNVR2+m1S835Pu6Brj4w2XDBtdsxcTRzLAGRNZ0ek1YUfRQay4KrGBYVwSP c/1mkMp1GSHwPMMZCV7oAdOOPyVA9oyXrssm/mTg12mdArxvR3+Vl5KYhLriakA9mb l/cnPm91MdLqYgXSXXTT03lz59Mp7424d4AfeLbVjh9oqanpGJ4zauMw5X2uFjzT2W TR2o7CkHFMIgi7kDWyK7afhFP1BP82PNGmcb4v/0pzFiydme+Isv5TB4vSibkKCO01 1I4uk/WoQjk6w== Date: Thu, 24 Sep 2026 08:38:18 +0100 From: "Lorenzo Stoakes (ARM)" To: Mikhail Gavrilov Cc: David Hildenbrand , Andrew Morton , Dave Hansen , "Liam R . Howlett" , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Michal Hocko , Vishal Moola , Ingo Molnar , Lu Baolu , Jason Gunthorpe , Steven Rostedt , x86@kernel.org, linux-mm@kvack.org, regressions@lists.linux.dev, linux-kernel@vger.kernel.org Subject: Re: [PATCH] mm: don't defer freeing kernel page tables while booting Message-ID: References: <41a59ba9-039e-454f-8d31-f647db802ada@kernel.org> <20260924072819.33277-1-mikhail.v.gavrilov@gmail.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=us-ascii Content-Disposition: inline In-Reply-To: <20260924072819.33277-1-mikhail.v.gavrilov@gmail.com> On Thu, Sep 24, 2026 at 12:28:19PM +0500, Mikhail Gavrilov wrote: > On 9/24/26 09:07, David Hildenbrand (Arm) wrote: > > Should we instead simply skip the > > > > schedule_work(&kernel_pgtable_work.work); > > > > and rely on anybody freeing stuff later to just free that one alongside? > > > > That avoids throwing in more freeing handling. > > Yes, that is simpler, and the early table then goes through the same > IOMMU flush as every other one, so there is no need to reason about > what an IOMMU can see during boot. The only cost is that it waits on > the list until the next kernel page table is freed after boot. > > I'll send a v2 that way once I have booted it here. Please wait for me to have a look through this issue before respinning, please. -- Cheers, Lorenzo