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 9C10CC433EF for ; Mon, 21 Mar 2022 19:47:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1352825AbiCUTsx (ORCPT ); Mon, 21 Mar 2022 15:48:53 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52618 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239684AbiCUTsv (ORCPT ); Mon, 21 Mar 2022 15:48:51 -0400 Received: from mail-lj1-x22c.google.com (mail-lj1-x22c.google.com [IPv6:2a00:1450:4864:20::22c]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 918B776297 for ; Mon, 21 Mar 2022 12:47:21 -0700 (PDT) Received: by mail-lj1-x22c.google.com with SMTP id c15so21323854ljr.9 for ; Mon, 21 Mar 2022 12:47:21 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux-foundation.org; s=google; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=lCiODI9PI/EEfC6nyI3suBU5YNtGDoGGxuNDXJnVdTA=; b=ezmZUQJ4kvMrHLo4x5F8XsnqcRGxtWgktJJ1WwpOwWXNKYLVOUbTbyhLyRBpe5o8Dt +g8PqbcgmlNrTRHqBe78ScSgYJYGnvcSIKiLY8zwdhx//bndxVsMOhUQyeXm2OUHo2AA zezBo+N6+i7TZSdnwddAT0+JYMamd1jr42bIE= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=lCiODI9PI/EEfC6nyI3suBU5YNtGDoGGxuNDXJnVdTA=; b=6ui9jIkNPq693m439szm2kXfNsYo3nSO+KYq4Q9L1mw69PHygeT9s30L7IIaPkUeiA oPKMp4WCrq5OwY7jSfRKCamZ2mhXxWhoMCBWC/gBacl+83KYQ5wuuRRp0CeMA6VWK5IM L5JdcsrIRtXk4Me1TsfL3FXp8ltC8NmrouKo2jvab8l4F47icgpJI07NbPiUjaRUqh36 wvmntImhbI79hLF8iUF2yjk5VmSDJ1kY700g+bU7yKRrDmge/ACNxZRcN+0cLLpajVZP H47kmibu7LeF/0LEs150HKIqiE0bXa9tajKnrSZTf49yh81nDaOYTR+iSMIiI9ZTwLjm GNww== X-Gm-Message-State: AOAM533SpTM2H1WN1r2DxDevlDUNjxV+L3WPje3f43+XGWJIVlpeZ15D Zjim7qeEziDpdLROBm09oNIXzfKdYMyxYVxNhhQ= X-Google-Smtp-Source: ABdhPJy95Ya2NviqIo9Bu3A+aYbg8txXV0UgttM7+noppa16CWI7gwYnqlki6lulBu/BfOewVsGJag== X-Received: by 2002:a05:651c:3cc:b0:249:800d:58ea with SMTP id f12-20020a05651c03cc00b00249800d58eamr6855403ljp.41.1647892039380; Mon, 21 Mar 2022 12:47:19 -0700 (PDT) Received: from mail-lf1-f54.google.com (mail-lf1-f54.google.com. [209.85.167.54]) by smtp.gmail.com with ESMTPSA id r25-20020ac25a59000000b00445b78bb876sm1893923lfn.295.2022.03.21.12.47.17 for (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Mon, 21 Mar 2022 12:47:18 -0700 (PDT) Received: by mail-lf1-f54.google.com with SMTP id a26so8337493lfg.10 for ; Mon, 21 Mar 2022 12:47:17 -0700 (PDT) X-Received: by 2002:a05:6512:2294:b0:448:6c86:3c78 with SMTP id f20-20020a056512229400b004486c863c78mr15188243lfu.531.1647892037101; Mon, 21 Mar 2022 12:47:17 -0700 (PDT) MIME-Version: 1.0 References: <164786042536.122591.4459156564791679956.tglx@xen13> In-Reply-To: <164786042536.122591.4459156564791679956.tglx@xen13> From: Linus Torvalds Date: Mon, 21 Mar 2022 12:47:01 -0700 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [GIT pull] core/core for v5.18-rc1 To: Thomas Gleixner , Oleg Nesterov Cc: Linux Kernel Mailing List , "the arch/x86 maintainers" Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Mar 21, 2022 at 4:02 AM Thomas Gleixner wrote: > > - Provide a mechanism to delay raising signals from atomic context on > PREEMPT_RT enabled kernels as sighand::lock cannot be acquired. Store > the information in the task struct and raise it in the exit path. This isn't super-pretty, but doing it conditionally makes it even uglier. I've pulled this, but my reaction to it all is "force_sig_info_to_task() isn't that critical, and CONFIG_RT_DELAYED_SIGNALS might as well have been unconditional". In fact, is there any reason to make it conditional even at run-time, ie this: > + if (!in_atomic()) > + return false; looks a bit unnecessary too. Why not just always do that thing and avoid having two code-paths? I really think we don't want more complexity in this unusual "force signal on exception" case, and TIF_NOTIFY_RESUME doesn't seem like it's the wrong place to do it. Hmm? Anyway, I've pulled it in this form, I just don't like the special cases that seem a bit pointless. They not only make the code bigger and more complex, they actively mean that test coverage is much worse too. Linus