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=-2.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no 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 186D2C433E6 for ; Tue, 16 Mar 2021 09:42:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id DE7C965013 for ; Tue, 16 Mar 2021 09:42:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234510AbhCPJll (ORCPT ); Tue, 16 Mar 2021 05:41:41 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45826 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234344AbhCPJlO (ORCPT ); Tue, 16 Mar 2021 05:41:14 -0400 Received: from mail-pj1-x1031.google.com (mail-pj1-x1031.google.com [IPv6:2607:f8b0:4864:20::1031]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 933FAC06174A; Tue, 16 Mar 2021 02:41:14 -0700 (PDT) Received: by mail-pj1-x1031.google.com with SMTP id ha17so9559614pjb.2; Tue, 16 Mar 2021 02:41:14 -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; bh=oWsgzNHBmSFzmgfMUIgNEjy4VDqIaNU2SVRo/jg0d5k=; b=FUjMUNH2UJER+BIC1s/zqmXPyt9FdzWbApAZEYZ2loBl6y4Fm52FF8XKIIAi1nOVXL Ctd3YhmifwqQXKW0k9lpxITsPuPeTFFTcmoQqQnvzDFQhVwkMBrf+DZPAdk5Zd5+TIIv wgVGKG2Gd05O6afK2zt+GHrTmr9eHRxkP56XZ/edYIg1RSmy3ZVgINfPD1hGYsPvGgYP 4eSbFA6YjyLi1SLMszXlQmGoytMMaH9Qjk8CqeTfCmjsZSZKy0V5evjhCDTXNsTu2cy/ VJdc5Ry7Rv/2QVJCLyTKENpi+VWCnV7POGMKXTNzBdhzC5CAsBvoDbPLxuqHgV48+nua tfxQ== 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; bh=oWsgzNHBmSFzmgfMUIgNEjy4VDqIaNU2SVRo/jg0d5k=; b=sMjUzjeawDEnXQp119TLtfHEcF5PIHnNm/miEO5lSMMenzWvJ3Q61HLvcTDbsbyaYL lhfAeEs8RR36CArSSne7ZOyDarjYOYiCCrleJ8Ao9BLtC+bObhZ2TWMCQTcq9yMyLrpO 3GY8u2Zgf/m+RX1lu/usO4K/bpkw4iABmfcfz/Rz1LIfgrWxsHr2Tu2GqR16jTNeBK3S V22df96lLI8jjr0k5UOTWMgQAkEJ8l8sZjmDLNdFqUFI9XgufOwfrE7IACCbbrO81wJE cTyCXZbBGPytIpdEJTheH12ZEP2DkMstmySlCDKJIUTsL8icI6zXU+qFTjRqn7r/Lhmp 4kRA== X-Gm-Message-State: AOAM533z/pWBdIt3iKV4fPtf2ANwGyvnhsjSDVBbVD+qdMyVtHCwMeYX Q1vqRCaaxbRN6O6s0mz0OptCFpzNl3F6n0rxMpsq8FRz29h2Mg== X-Google-Smtp-Source: ABdhPJwok/lbNgZz/ECDiA9AlOZaJkUAwDTgC3x5B7ogt15ycGrugVCd4mp242t636AUkmfYjwe5vuVRgngmGPn1nxk= X-Received: by 2002:a17:90a:e454:: with SMTP id jp20mr4104940pjb.129.1615887673725; Tue, 16 Mar 2021 02:41:13 -0700 (PDT) MIME-Version: 1.0 References: <20210315181212.113217-1-krzysztof.kozlowski@canonical.com> In-Reply-To: From: Andy Shevchenko Date: Tue, 16 Mar 2021 11:40:57 +0200 Message-ID: Subject: Re: [PATCH] tty: serial: samsung_tty: remove spinlock flags in interrupt handlers To: Johan Hovold , Finn Thain , Barry Song Cc: Krzysztof Kozlowski , Greg Kroah-Hartman , Jiri Slaby , linux-arm Mailing List , Linux Samsung SOC , "open list:SERIAL DRIVERS" , Linux Kernel Mailing List , Hector Martin , Arnd Bergmann Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Mar 16, 2021 at 11:02 AM Johan Hovold wrote: > > On Mon, Mar 15, 2021 at 07:12:12PM +0100, Krzysztof Kozlowski wrote: > > Since interrupt handler is called with disabled local interrupts, there > > is no need to use the spinlock primitives disabling interrupts as well. > > This isn't generally true due to "threadirqs" and that can lead to > deadlocks if the console code is called from hard irq context. > > Now, this is *not* the case for this particular driver since it doesn't > even bother to take the port lock in console_write(). That should > probably be fixed instead. > > See https://lore.kernel.org/r/X7kviiRwuxvPxC8O@localhost. Finn, Barry, something to check I think? -- With Best Regards, Andy Shevchenko