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 15926C43219 for ; Fri, 4 Nov 2022 18:39:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230089AbiKDSjE (ORCPT ); Fri, 4 Nov 2022 14:39:04 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56980 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232163AbiKDSjB (ORCPT ); Fri, 4 Nov 2022 14:39:01 -0400 Received: from mail-oi1-x229.google.com (mail-oi1-x229.google.com [IPv6:2607:f8b0:4864:20::229]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 34A30101EF for ; Fri, 4 Nov 2022 11:39:00 -0700 (PDT) Received: by mail-oi1-x229.google.com with SMTP id g10so6039691oif.10 for ; Fri, 04 Nov 2022 11:39:00 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=cc:to:subject:message-id:date:from:in-reply-to:references :mime-version:from:to:cc:subject:date:message-id:reply-to; bh=/eaHXmf2PauUwbh2A2MPaTE0oM/kMlZ6+C9nCeVhgAw=; b=FyjO4GDxglnTZnbVJEnTCkM+ad0b9tWkBlCHI7YLLDoBs/T8qFEQJKEEU06ltOCbr6 NblIeD8IQYWUjWFcpKC7EWaF48cB0iyIpio+/1g1lIXMDJYh0wN6taWvLZkLeOeHdSeJ VQ1qQ3Nlb2uZAvc966/fN/XQAFDLSTqZbDrv2TxWY8Y9MuUsRo3HsnbP6F0nC0J9DsDk ZGfIiJg9tIOvhGlUnT/vblhTlS1l8DCLi/XzhBGuPVbEDvbhM3NoeWEQQniOeV2kQ6HX EnfiPtcoNp/rIuJtyqtY4RJhmHmMdElTe0i0INQquZR1n17KZPjUvI/HZLy6eCbdHsyd 0nbg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=cc:to:subject:message-id:date:from:in-reply-to:references :mime-version:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=/eaHXmf2PauUwbh2A2MPaTE0oM/kMlZ6+C9nCeVhgAw=; b=SjCsS6lzdpSV/loEKChuxJSCTwCoqGBjYmFeaZOCVT+Hbtb8ac1KLoYjf21vfw5FDu fnv/eNonk9BMZqtZzf0nTaTGaNBa27Zn5smDt1xQcI1jrKZDhcvrR2OBBGMGpJs3zx9J HeHEn8gA48IdZnn6krgPYcM1iy7q7h6eHQkuV9tyzNTH7kLlFaf3XkuQzKkRbTrFiPfW +2ETY/cZriZ2ZFLCcCU6rK/nRbtGcGvq3xOKpERSyj8H2/na6hHCf/MEiL+Zw8nuYS70 NpEuiFcOkFfv7oZT9kyo0X91xowb65s8+Rm/9ZzhmJQtNhAMOZUT/Wfl3bUrKGJ2qAal rX8Q== X-Gm-Message-State: ACrzQf3cdvpzOua2r0XbWRap5RaXL9dnxMQWJs9YwkJG2PoTLsrkT8gR 2//QAyOtNwhy1ND+Xz7Li65+BHtu3PV0DkhVTzeO/g== X-Google-Smtp-Source: AMsMyM4dp0XXTZUH2UpiSDVwfSTLQVkRqIkPeHMzsLPQhJ35ipysopTbp06N1YUyt5vY4qn4Vt0xZdJG2edZHfmRc4Y= X-Received: by 2002:a05:6808:1184:b0:350:f681:8c9a with SMTP id j4-20020a056808118400b00350f6818c9amr20243199oil.282.1667587139286; Fri, 04 Nov 2022 11:38:59 -0700 (PDT) MIME-Version: 1.0 References: In-Reply-To: From: Dmitry Vyukov Date: Fri, 4 Nov 2022 11:38:48 -0700 Message-ID: Subject: Re: xarray, fault injection and syzkaller To: Jason Gunthorpe Cc: zhengqi.arch@bytedance.com, Matthew Wilcox , Akinobu Mita , linux-fsdevel@vger.kernel.org, syzkaller-bugs@googlegroups.com, syzkaller Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org On Fri, 4 Nov 2022 at 11:30, Jason Gunthorpe wrote: > On Fri, Nov 04, 2022 at 11:21:21AM -0700, Dmitry Vyukov wrote: > > > But I am not sure if we really don't want to issue the fault injection > > stack in this case. It's not a WARNING, it's merely an information > > message. It looks useful in all cases, even with GFP_NOWARN. Why > > should it be suppressed? > > I think it is fine to suppress it for *this call* but the bug turns it > off forever more Is it just "fine", or "good"? I agree it's probably "fine", but wouldn't it be better to not suppress it? The message fault injection prints is not a warning, and the allocation failed due to fault injection. That may trigger subsequent bugs just as any other case of fault injection. Why don't we want to see the info message in this particular case? NOWARN looks orthogonal to this, it's about normal slab allocation failures.