From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 EDB63286412; Sun, 8 Mar 2026 17:23:16 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772990597; cv=none; b=UcqAVlZKBurGLSAxMpHkkehx08H8IanslVA7E2PMNf01cE8Msqyo9TYmtHDhABqxltKb737Qvj/Xhj4RtTAmV11vY77o+N3dIypFqCyfehiCh9PDgT1WTAvWtp241+pGBq+MbB8T4S8yNfsfpPZjl8U4cDFXNdV4dBEgDCieZuU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772990597; c=relaxed/simple; bh=aKTiLeBUT/yyVrfF+UX9Dm/tjm0IVzbkGDksBmzpY0Y=; h=Date:From:To:Cc:Message-ID:In-Reply-To:References:Subject: MIME-Version:Content-Type; b=PioeYBUGINGx9gCVU2T51vtI971lTBzSDOiS+B2wZpQOjhVgbgbqoxcEstd3hsvcDntq2wAtGFZoQRGjqhkq4dJTpEG6G0bF1kUJHoZi2CRWgBwH7PZ1AkMndoX0N4Hi3NxUI7OGoSBYiUJK4yOUpHLuPkicdqAPkZ4NKRKd1Gc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=AxLf6j4G; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="AxLf6j4G" Received: by smtp.kernel.org (Postfix) with ESMTPSA id DC301C116C6; Sun, 8 Mar 2026 17:23:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1772990596; bh=aKTiLeBUT/yyVrfF+UX9Dm/tjm0IVzbkGDksBmzpY0Y=; h=Date:From:To:Cc:In-Reply-To:References:Subject:From; b=AxLf6j4GvGHT+C8ZRyPQ8SdmNN8dUN+vRNWyNZgN/eeKcMM83VgsKiv2Thvnni7mF CfgmTPF5cBDong5YKy9PoAEZZLFYWmSGaY/yFgJtjGTUB++iQ0ZTbwUwg41cVL2Hb4 aVDzcTTxsw+4N3cFJLEvBKbS0+/gIDH6gRh1dsIbaYxkTvJmMEHmDQkpGBhoMAbTtQ yiPpUo051i5ohiLr/B8HHuV9Jw6JIpHsXv65F8axnnjl4GvPp5YG5dLQbEOC3wVSye wmL+EvQq9IJY1MIDsWdo/YtrWIjcfslHSeKCRPBvaG1GdZz4KFU1L8KJDa5bRAczNO ioxyQ4Cvo8vUQ== Date: Sun, 8 Mar 2026 18:23:08 +0100 From: Matthieu Baerts To: Thomas Gleixner Cc: Peter Zijlstra , Jiri Slaby , Stefan Hajnoczi , Stefano Garzarella , kvm@vger.kernel.org, virtualization@lists.linux.dev, Netdev , rcu@vger.kernel.org, MPTCP Linux , Linux Kernel , Shinichiro Kawasaki , "Paul E. McKenney" , Dave Hansen , luto@kernel.org, =?UTF-8?Q?Michal_Koutn=C3=BD?= , Waiman Long , Marco Elver Message-ID: <57c1e171-9520-4288-9e2d-10a72a499968@kernel.org> In-Reply-To: <87v7f61cnl.ffs@tglx> References: <863a5291-a636-47d0-891c-bb0524d2e134@kernel.org> <20260302114636.GL606826@noisy.programming.kicks-ass.net> <717310d8-6274-4b7f-8a19-561c45f5f565@kernel.org> <87zf4m2qvo.ffs@tglx> <47cba228-bba7-4e58-a69d-ea41f8de6602@kernel.org> <87tsuu2i59.ffs@tglx> <7efde2b5-3b72-4858-9db0-22493d446301@kernel.org> <87qzpx2sck.ffs@tglx> <20260306152458.GT606826@noisy.programming.kicks-ass.net> <87ldg42eu7.ffs@tglx> <87h5qr2rzi.ffs@tglx> <87eclu3coa.ffs@tglx> <87v7f61cnl.ffs@tglx> Subject: Re: Stalls when starting a VSOCK listening socket: soft lockups, RCU stalls, timeout Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Correlation-ID: <57c1e171-9520-4288-9e2d-10a72a499968@kernel.org> 08 Mar 2026 17:58:26 Thomas Gleixner : > On Sun, Mar 08 2026 at 10:15, Thomas Gleixner wrote: > >> On Sat, Mar 07 2026 at 23:29, Thomas Gleixner wrote: >>> I'll look at it more tomorrow in the hope that this rested brain >>> approach works out again. >> >> There is another one of the same category. Combo patch below. > > This rested brain thing is clearly a myth. The patch actually solves > nothing because the code ensures that the TRANSIT bit is never set > together with the ONCPU bit. Thank you for having shared these patches. I confirm the myth: I can still reproduce the issue on my side. > One of those moments where you just hope that the earth opens up and > swallows you. > > So I'm back to square one. I go and do what I should have done in the > first place. Write a debug patch with trace_printks and let the people > who can actually trigger the problem run with it. Happy to test such debug patches! Cheers, Matt