From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 33014C4332F for ; Sun, 11 Dec 2022 10:54:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230140AbiLKKyG (ORCPT ); Sun, 11 Dec 2022 05:54:06 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51302 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229656AbiLKKyD (ORCPT ); Sun, 11 Dec 2022 05:54:03 -0500 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id CF4D6FAE1 for ; Sun, 11 Dec 2022 02:53:59 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 680A460A10 for ; Sun, 11 Dec 2022 10:53:59 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1FA19C433EF; Sun, 11 Dec 2022 10:53:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1670756038; bh=XkNMpwy/87CeF1FK5TaclU8fX8nQmPRMYKk9Fu8hnbc=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=Z1WVdgDq1VgFdgHzq9axxDp01F5qZry0NZRQwQ17tY1qqTlXYGdpuqudSiz/utboX B+u80X8zLbADRo0+0cTfgq3CCwh2IAGizL+bEO2w2Ct5i6krEQX9O/1gYNf21V4X4e rQxOrxIQ/r+FsHOd+gtT5QizAvu5sObNyaS4cojujZ2Yc5SAOhoMdgMW8c+zs6Xij6 TBTlKesLgf0nyIgC0FzwprNHHjCSN4XG1N80ltB/bwLxnOJl3n79el4SJhqLwEKdEQ N9VowYbVSmoH+x58p9H2yzz1LSJpZ0snjT1mu063AZLunVBtpAABeXJqm/rM0FHKc9 qVaXC0af/2ZCQ== Date: Sun, 11 Dec 2022 18:43:58 +0800 From: Jisheng Zhang To: Palmer Dabbelt Cc: Paul Walmsley , aou@eecs.berkeley.edu, ryabinin.a.a@gmail.com, glider@google.com, andreyknvl@gmail.com, dvyukov@google.com, vincenzo.frascino@arm.com, alexandre.ghiti@canonical.com, linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org, kasan-dev@googlegroups.com Subject: Re: [PATCH v6 RESEND 0/2] use static key to optimize pgtable_l4_enabled Message-ID: References: <20220821140918.3613-1-jszhang@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, Oct 08, 2022 at 10:28:35PM +0800, Jisheng Zhang wrote: > On Thu, Oct 06, 2022 at 04:37:57PM +0800, Jisheng Zhang wrote: > > On Wed, Oct 05, 2022 at 06:05:28PM -0700, Palmer Dabbelt wrote: > > > On Sun, 21 Aug 2022 07:09:16 PDT (-0700), jszhang@kernel.org wrote: > > > > The pgtable_l4|[l5]_enabled check sits at hot code path, performance > > > > is impacted a lot. Since pgtable_l4|[l5]_enabled isn't changed after > > > > boot, so static key can be used to solve the performance issue[1]. > > > > > > > > An unified way static key was introduced in [2], but it only targets > > > > riscv isa extension. We dunno whether SV48 and SV57 will be considered > > > > as isa extension, so the unified solution isn't used for > > > > pgtable_l4[l5]_enabled now. > > > > > > > > patch1 fixes a NULL pointer deference if static key is used a bit earlier. > > > > patch2 uses the static key to optimize pgtable_l4|[l5]_enabled. > > > > > > > > [1] http://lists.infradead.org/pipermail/linux-riscv/2021-December/011164.html > > > > [2] https://lore.kernel.org/linux-riscv/20220517184453.3558-1-jszhang@kernel.org/T/#t > > > > > > > > Since v5: > > > > - Use DECLARE_STATIC_KEY_FALSE > > > > > > > > Since v4: > > > > - rebased on v5.19-rcN > > > > - collect Reviewed-by tags > > > > - Fix kernel panic issue if SPARSEMEM is enabled by moving the > > > > riscv_finalise_pgtable_lx() after sparse_init() > > > > > > > > Since v3: > > > > - fix W=1 call to undeclared function 'static_branch_likely' error > > > > > > > > Since v2: > > > > - move the W=1 warning fix to a separate patch > > > > - move the unified way to use static key to a new patch series. > > > > > > > > Since v1: > > > > - Add a W=1 warning fix > > > > - Fix W=1 error > > > > - Based on v5.18-rcN, since SV57 support is added, so convert > > > > pgtable_l5_enabled as well. > > > > > > > > > > > > Jisheng Zhang (2): > > > > riscv: move sbi_init() earlier before jump_label_init() > > > > riscv: turn pgtable_l4|[l5]_enabled to static key for RV64 > > > > > > > > arch/riscv/include/asm/pgalloc.h | 16 ++++---- > > > > arch/riscv/include/asm/pgtable-32.h | 3 ++ > > > > arch/riscv/include/asm/pgtable-64.h | 60 ++++++++++++++++++--------- > > > > arch/riscv/include/asm/pgtable.h | 5 +-- > > > > arch/riscv/kernel/cpu.c | 4 +- > > > > arch/riscv/kernel/setup.c | 2 +- > > > > arch/riscv/mm/init.c | 64 ++++++++++++++++++----------- > > > > arch/riscv/mm/kasan_init.c | 16 ++++---- > > > > 8 files changed, 104 insertions(+), 66 deletions(-) > > > > > > Sorry for being slow here, but it looks like this still causes some early > > > boot hangs. Specifically kasan+sparsemem is failing. As you can probably > > > see from the latency I'm still a bit buried right now so I'm not sure when > > > I'll have a chance to take more of a look. > > > > Hi Palmer, > > > > Before V4, there is a bug which can cause kernel panic when SPARSEMEM > > is enabled, V4 have fixed it by moving the riscv_finalise_pgtable_lx() > > after sparse_init(). And I just tested the riscv-pgtable_static_key > > branch in your tree, enabling KASAN and SPARSEMEM, system booted fine. > > I'm not sure what happened. Could you please send me your kernel > > config file? I want to fix any issue which can block this series being > > merged in 6.1-rc1. > > Hi Palmer, > > I know you are busy ;) Do you have time to send me your test kernel > config file so that I can reproduce the "early boot hang"? > > Thanks Hi Palmer, I think the early boot hangs maybe the same as the one which has been fixed by commit 9f2ac64d6ca6 ("riscv: mm: add missing memcpy in kasan_init"). Will you give this series another try for v6.2-rc1? If the boot hang can still be reproduced, could you please send me your .config file? Thanks in advance