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 X-Spam-Level: X-Spam-Status: No, score=-10.1 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 876D1C433E7 for ; Mon, 13 Jul 2020 10:07:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6410A20758 for ; Mon, 13 Jul 2020 10:07:22 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="ptiRUWo4" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729742AbgGMKHV (ORCPT ); Mon, 13 Jul 2020 06:07:21 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43882 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726523AbgGMKHU (ORCPT ); Mon, 13 Jul 2020 06:07:20 -0400 Received: from mail-qt1-x844.google.com (mail-qt1-x844.google.com [IPv6:2607:f8b0:4864:20::844]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8997CC061755; Mon, 13 Jul 2020 03:07:20 -0700 (PDT) Received: by mail-qt1-x844.google.com with SMTP id j10so9431677qtq.11; Mon, 13 Jul 2020 03:07:20 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc:content-transfer-encoding; bh=Hra1SVxTdrHnmSqT77/bjMGWIFkz435wwiQ+ZLnZoDI=; b=ptiRUWo4gXYQycmEkPKTyJJZRN7Bj54mqkYIggzhcdgIJddti3yb3pwt2oKuq5Q0Y0 WjRZjIT2ThsoI09IUDHLACAsItQWoXa0IyjIue11vonhfNd670q6xTS4V3v97YgiDQMA 9yR5LmgfcdAQcV0tZN6ZvDXveHjOeIcK+uy24VE8hssRLCTGam408lxayc6b7XsN6Q7P /Hg5geh/iVhe2vjX46XGDIe3OpMNLs4eV7XDlhV5kAKDDMQ93DvVh1CI0Lqh5zWXIOu9 6sZow05O2kidzix7prq9gGoF0WJeZHV8Y+YxmAp2F367+5dENJvvpy2Aqcwb5eiIAX0R J+RQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc:content-transfer-encoding; bh=Hra1SVxTdrHnmSqT77/bjMGWIFkz435wwiQ+ZLnZoDI=; b=jTrUxht2E1x/Jw3GYYYmUzBBNUi9lDYZz9oM7nav2+kZAmuJgSfhdZbUSX1+B/dnAe R8DP182GBUiwrrJCF1XTz9tQHttVeRJODaK9gi35VHU5t8LS8aCL7hmjt07wBNScNM2d if/MDxREonRT3fdOCb4lJzffgUnmbXm2BA2X3rvmx+76PxdVwPqLJqnlv2e1QNQ2V6Az RaaeAkaACPD9pfBbPRsHbz4rLhHQpafOsYbS/y5MiKZ2fyk7aEsME/fCb73bHbv8fJR1 eSbbEvVL+Gfk0pICU6dV2BdZ5BLw9cx8Z0CBUWo+/Nx39qi6JzXon5NrPTyU/mFzdQ6K SCMQ== X-Gm-Message-State: AOAM530WB9FDWrj4tsFfhYqgssl+cFXU/g7/RdglvCXwWCOL851BZFe/ Q8cCDs6UJMM2CcKsWeH67vBZsJRZmWsPrHVC4WE= X-Google-Smtp-Source: ABdhPJx2Tkh9kzNP5zejlcgntpWG6iqUsWwAdhz/7Y2gf+TeAPNupDdNYWVSICr1330Epz0MkIk6TUJ4OuKUEr4Uoj0= X-Received: by 2002:ac8:19c4:: with SMTP id s4mr79036237qtk.117.1594634839691; Mon, 13 Jul 2020 03:07:19 -0700 (PDT) MIME-Version: 1.0 References: <20200710135706.537715-1-hch@lst.de> <20200710135706.537715-6-hch@lst.de> In-Reply-To: <20200710135706.537715-6-hch@lst.de> From: Greentime Hu Date: Mon, 13 Jul 2020 18:06:42 +0800 Message-ID: Subject: Re: [PATCH 5/6] uaccess: add force_uaccess_{begin,end} helpers To: Christoph Hellwig Cc: Nick Hu , Vincent Chen , Paul Walmsley , Palmer Dabbelt , Andrew Morton , Linus Torvalds , linux-riscv@lists.infradead.org, linux-arch , Linux Kernel Mailing List Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Christoph Hellwig =E6=96=BC 2020=E5=B9=B47=E6=9C=8810=E6=97=A5= =E9=80=B1=E4=BA=94 =E4=B8=8B=E5=8D=889:57=E5=AF=AB=E9=81=93=EF=BC=9A > > Add helpers to wraper the get_fs/set_fs magic for undoing any damange > done by set_fs(KERNEL_DS). There is no real functional benefit, but this > documents the intent of these calls better, and will allow stubbing the > functions out easily for kernels builds that do not allow address space > overrides in the future. > > Signed-off-by: Christoph Hellwig > --- > arch/arm64/kernel/sdei.c | 2 +- > arch/m68k/include/asm/tlbflush.h | 12 ++++++------ > arch/mips/kernel/unaligned.c | 27 +++++++++++++-------------- > arch/nds32/mm/alignment.c | 7 +++---- > arch/sh/kernel/traps_32.c | 18 ++++++++---------- > drivers/firmware/arm_sdei.c | 5 ++--- > include/linux/uaccess.h | 18 ++++++++++++++++++ > kernel/events/callchain.c | 5 ++--- > kernel/events/core.c | 5 ++--- > kernel/kthread.c | 5 ++--- > kernel/stacktrace.c | 5 ++--- > mm/maccess.c | 22 ++++++++++------------ > 12 files changed, 69 insertions(+), 62 deletions(-) > [...] > diff --git a/arch/nds32/mm/alignment.c b/arch/nds32/mm/alignment.c > index c8b9061a2ee3d5..1eb7ded6992b57 100644 > --- a/arch/nds32/mm/alignment.c > +++ b/arch/nds32/mm/alignment.c > @@ -512,7 +512,7 @@ int do_unaligned_access(unsigned long addr, struct pt= _regs *regs) > { > unsigned long inst; > int ret =3D -EFAULT; > - mm_segment_t seg =3D get_fs(); > + mm_segment_t seg; > > inst =3D get_inst(regs->ipc); > > @@ -520,13 +520,12 @@ int do_unaligned_access(unsigned long addr, struct = pt_regs *regs) > "Faulting addr: 0x%08lx, pc: 0x%08lx [inst: 0x%08lx ]\n", a= ddr, > regs->ipc, inst); > > - set_fs(USER_DS); > - > + seg =3D force_uaccess_begin(); > if (inst & NDS32_16BIT_INSTRUCTION) > ret =3D do_16((inst >> 16) & 0xffff, regs); > else > ret =3D do_32(inst, regs); > - set_fs(seg); > + force_uaccess_end(seg); > > return ret; > } Hi Christoph, Thank you. Acked-by: Greentime Hu