From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mo1.intermailgate.com (mo1.intermailgate.com [91.203.103.210]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id D40523FC1 for ; Tue, 31 Aug 2021 04:54:23 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by mo1.intermailgate.com (Postfix) with ESMTP id 45FAE2046A for ; Tue, 31 Aug 2021 06:47:02 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=bof.de; s=20180522; t=1630385222; bh=vQBdUiphtsfPgcBs1AS+zxaL3pEfW5kH2Eao5L+/iFI=; h=References:In-Reply-To:From:Date:Subject:To:Cc; b=cLUOMyYYn8QbGbvAxPPuZeQCptVn7RKGefwMVnosYucpnbmtIHAvkHiOvehZfzUM9 gUnsv5zgdu3LzXsKbytl2LOL/c+5th2WePSQQMgAuvK64zy2Pa0mCACZ0qwbEli/fb 4Bs309qMEimaoD/s2dE6luJe+wMSqoqCANDt3ooI= Received: from mail-lf1-f41.google.com (unknown [162.158.183.169]) by mo1.intermailgate.com (Postfix) with ESMTPSA id CAE4820467 for ; Tue, 31 Aug 2021 06:46:57 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=bof.de; s=20180522; t=1630385217; bh=vQBdUiphtsfPgcBs1AS+zxaL3pEfW5kH2Eao5L+/iFI=; h=References:In-Reply-To:From:Date:Subject:To:Cc; b=ZxinhJJ8hmfV9BJdQ6RgnXW2VXoPit68KuReBaRQmKXCyBohs4o1Za48sfmj2Gau1 WDzL9/0XR17qNk/6hneM6XICFS2BO9vimdJuZjX9T1Vlt+ZrbedhTzBs1AuyS6Rif8 Vrq64DFBNNoxmYuxMZyNLJhPcWx/ukfk4TZU3ACA= Received: by mail-lf1-f41.google.com with SMTP id c8so23233429lfi.3 for ; Mon, 30 Aug 2021 21:46:57 -0700 (PDT) X-Gm-Message-State: AOAM530MZ30beUryhWIm6yNtzMJzNfy60xVFYebgQ6B2p7nxK/CPDZ+Q T47/r4uiU3pS6u+B5CjFu37i67u0wXm1XGsrYJg= X-Google-Smtp-Source: ABdhPJzVdkO4u/llKb099ZNjucQmxyXekgdRXv7+Fbjpmh0/kyTt2c4StQ3wVFzF6/ZHimiDdFS6iBysPMobUZZPwJc= X-Received: by 2002:a05:6512:3188:: with SMTP id i8mr15909765lfe.209.1630385217206; Mon, 30 Aug 2021 21:46:57 -0700 (PDT) Precedence: bulk X-Mailing-List: regressions@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 References: <61018d93.xsvXcO161PFLQFCX%bof@bof.de> In-Reply-To: From: Patrick Schaaf Date: Tue, 31 Aug 2021 06:46:40 +0200 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: stable 5.4.135 REGRESSION / once-a-day WARNING: at kthread_is_per_cpu+0x1c/0x20 To: stable@vger.kernel.org Cc: regressions@lists.linux.dev, anubis@igorloncarevic.com, peterz@infradead.org Content-Type: text/plain; charset="UTF-8" Looking into this again. Unfortunately, couldn't see how I would do bisection on the issue, as it appears with that 5.4.118 commit implicated by the call stack,and with tha tremoved,is obviously gone(that I tested, 5.4.135 with b56ad4febe67b8c0647c0a3e427e935a76dedb59 reverted runs smoothly for me, while the original 5.4.135 with that 5.4.118 time commit in, now on a dozen machines, throws the WARNING. I got email on the side of someone (Igor, on Cc) who sees the same with DELL servers, a newer 5.10 kernel, for him running IPVS + he sees actual operational impact there. I just had a look at Linus mainlinetree, and see there is this followup / further fix from Peter Zijlstra, https://github.com/torvalds/linux/commit/3a7956e25e1d7b3c148569e78895e1f3178122a9 ; now I'm much too incompetent to try and backport that, as it looks more involved, but I imagine such a backport would be needed to fix the WARNING (or IPVS breakage of Igor) we see. best regards Patrick