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 47BC752BE38; Tue, 8 Sep 2026 11:30:12 +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=1788867026; cv=none; b=YT92slRTrOMqfA87u6tfrJLNlf8NX88d+Y7qVh+4CWsMlHocx3v+v8BOajhTFGG3UlX+UmIFiQ+Y3iAHAp+9DMO8b5xUrVk5C4MrWNKGTMDR829HPiyyOmn+riD/vZS6jpWYkLEYO5kfj6uvCPblgcG5IB3HSagd8H4hhl3Xc44= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788867026; c=relaxed/simple; bh=ZdXaRe4HWFBmLd0LXW6U2l7QcS01R5ntbQH6pp65rHQ=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=qikEAugHdvTIsVkwics2AwHjF6julDNkV/CZvkS/mHdAzkfbxjU+8okx2w/cKFwyRTtEm1LSYP7mLrFAnmwXETJBdfPuRL/2n2xs5rohMDrCuqGCCeGTuQHp/MgYFZtkbB2DMfD03uT9a/xriseRuB/xUqDExZ8XLMDVhjvca+4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=BbzZ3F73; 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="BbzZ3F73" Received: by smtp.kernel.org (Postfix) with ESMTPSA id F1CBD1F00A3A; Tue, 8 Sep 2026 11:29:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1788867009; bh=mB8nfc2dyoUj8MneI5XtqKUJWAX+H2A9jp3sF5M1qbA=; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=BbzZ3F73x9vlPWvAcrfnuEIBJXW3qsffsRXzmqRI35CWZGCBYksgG+FZ6D4aufx7+ sEVq9yImHXZGqNWFVp5OCg/tUPoqmbCnXM4gOVpEztvlmpfzA1qGnFHu5hqumBWzdY N5H85H7ubmL/KpLoi3BPX0MUJ8xr61MTWOAacXoR48MSTMJ0Wfiiqe1Y/y4kuLcp+l khOBR7+6+n4ltCTDSLtuvWLW78S/WOu2iBGYFFag5m3jqVXrl0QqQoIKHO1R75ph5X Qb1cRBjIYoRUQrLjUPvWxDGa1pvp8BiecTbRNMlM0odqliUSIGX+UuU4BPhFAXN8b9 dTjdPKOeABgjg== Date: Tue, 8 Sep 2026 12:29:46 +0100 From: "Lorenzo Stoakes (ARM)" To: Suren Baghdasaryan Cc: Kiryl Shutsemau , Andrew Morton , David Hildenbrand , Zi Yan , Baolin Wang , "Liam R. Howlett" , Nico Pache , Ryan Roberts , Dev Jain , Barry Song , Lance Yang , Usama Arif , Guo Ren , Brian Cain , Geert Uytterhoeven , Dinh Nguyen , Simon Schuster , Jonas Bonn , Stefan Kristiansson , Stafford Horne , Yoshinori Sato , Rich Felker , John Paul Adrian Glaubitz , Paul Walmsley , Palmer Dabbelt , Albert Ou , Alexandre Ghiti , Russell King , Vineet Gupta , Michal Simek , Chris Zankel , Max Filippov , Will Deacon , "Aneesh Kumar K.V" , Nick Piggin , Peter Zijlstra , "David S. Miller" , Andreas Larsson , Richard Henderson , Matt Turner , Magnus Lindholm , Catalin Marinas , Mark Rutland , Huacai Chen , WANG Xuerui , Thomas Bogendoerfer , "James E.J. Bottomley" , Helge Deller , Madhavan Srinivasan , Michael Ellerman , "Christophe Leroy (CS GROUP)" , Heiko Carstens , Vasily Gorbik , Alexander Gordeev , Christian Borntraeger , Sven Schnelle , Richard Weinberger , Anton Ivanov , Johannes Berg , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, "H. Peter Anvin" , Arnd Bergmann , Vlastimil Babka , Mike Rapoport , Michal Hocko , Jason Gunthorpe , John Hubbard , Peter Xu , linux-mm@kvack.org, linux-kernel@vger.kernel.org, linux-csky@vger.kernel.org, linux-hexagon@vger.kernel.org, linux-m68k@lists.linux-m68k.org, linux-openrisc@vger.kernel.org, linux-sh@vger.kernel.org, linux-riscv@lists.infradead.org, linux-arm-kernel@lists.infradead.org, linux-snps-arc@lists.infradead.org, linux-arch@vger.kernel.org, sparclinux@vger.kernel.org, linux-alpha@vger.kernel.org, loongarch@lists.linux.dev, linux-mips@vger.kernel.org, linux-parisc@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-s390@vger.kernel.org, linux-um@lists.infradead.org, Hugh Dickins , Qi Zheng Subject: Re: [PATCH 12/12] mm: change the contract for free_pgtables(), update docs Message-ID: References: <20260901-rcu-pagetable-freeing-v1-0-5456a81c8212@kernel.org> <20260901-rcu-pagetable-freeing-v1-12-5456a81c8212@kernel.org> Precedence: bulk X-Mailing-List: sparclinux@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: On Mon, Sep 07, 2026 at 09:53:43AM -0700, Suren Baghdasaryan wrote: > On Tue, Sep 1, 2026 at 10:25 AM Lorenzo Stoakes (ARM) wrote: > > > > So, maybe something like: > > > > > > > > * Note that free_pgtables(), used after unampping detached vmas, or when > > > > * exiting the whoel mm, does not take a page table lock before freeing a page > > > > * table. > > > > * > > > > * As page table freeing itself is RCU-safe, page table readers can safely run > > > > * concurrently with page table teardown. However, writers cannot, as without > > > > * a lock nothing prevents concurrent teardown. > > > > */ > > > > > > > > Instead? What do you think? > > > > > > s/whoel/whole/ > > > > Haha yup the inevitable typo... > > Also s/unampping/unmapping please. Ack will fix on respin! I am the typo master ;) -- Cheers, Lorenzo