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 CDDEC1F8753 for ; Fri, 11 Jul 2025 22:55:08 +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=1752274508; cv=none; b=Ik93wtNMuxS30MEI3CaZP2K4qOwX+M9piLmsys0BvqotC8ck/b8jG6L3gSxxjeamwrkGnMXpdLFaPZVK5y3SMhaxDKvHSft/vik7CzZnBPNWgozVpDGtU+jSi7/0wwJv2ktHKydN4mwNPL/btzxP4YgYqJifhqeeFSOA9JGQCyQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1752274508; c=relaxed/simple; bh=HEKZfpRkIsfMTw0VbZyXcU8BMmLR1OdTiN+k7zqLJcU=; h=Date:From:To:Cc:Subject:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=iAZkiSPc2iyXJPgdS1k20r4ovf0fHFV7havqK2MtnSDMUt0/dfbdb8FVUOZKhU/vSIPSZ3UZrh4+iniTW7GQkvL5cD8xQZtjHNDPUqGys8eS4FlUOyo3iilZ7lwa3u1w7Rfv1r+bWB0Zreed2Mmhd5w2GRiiJPZ9IXL3U5+C0fM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=Qjmv2Nma; 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="Qjmv2Nma" Received: by smtp.kernel.org (Postfix) with ESMTPSA id CFB6AC4CEED; Fri, 11 Jul 2025 22:55:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1752274508; bh=HEKZfpRkIsfMTw0VbZyXcU8BMmLR1OdTiN+k7zqLJcU=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=Qjmv2NmaWdDa+l9pKK1wRneUpEEc/I98xiWx+Enx1jP5j6gc+Yho0GIZJecQtGG95 AIGjIEshD9imogqUIuD/zEpMQSNJ1i144cvm/dcMKcc/GdDtUHeolatiOdVdigLhay SxXicVvdH6B+PmBhCPQjw1pU2lH6Yqlp4HwnRrrf+rqTMntlH3qwtMjeclgHZaF5ZV 9pSRrmQ0BTfOGTk7p/hpZHA3lSeVEzWMN2P3m37xuf1CrqqmZmOapHZ4wVUMw9a5jb pcPkoPPzabmFJhvJl6GGUW04MJpz4e8RqJwXg58aPcqRBCUMXJExqHR00m947oO1un wDylyDLww87pQ== Date: Fri, 11 Jul 2025 15:55:06 -0700 From: Jakub Kicinski To: William Liu Cc: netdev@vger.kernel.org, jhs@mojatatu.com, xiyou.wangcong@gmail.com, victor@mojatatu.com, pctammela@mojatatu.com, pabeni@redhat.com, stephen@networkplumber.org, dcaratti@redhat.com, savy@syst3mfailure.io, jiri@resnulli.us, davem@davemloft.net, edumazet@google.com, horms@kernel.org Subject: Re: [PATCH net v5 1/2] net/sched: Restrict conditions for adding duplicating netems to qdisc tree Message-ID: <20250711155506.48bbb351@kernel.org> In-Reply-To: <20250708164141.875402-1-will@willsroot.io> References: <20250708164141.875402-1-will@willsroot.io> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit On Tue, 08 Jul 2025 16:43:26 +0000 William Liu wrote: > netem_enqueue's duplication prevention logic breaks when a netem > resides in a qdisc tree with other netems - this can lead to a > soft lockup and OOM loop in netem_dequeue, as seen in [1]. > Ensure that a duplicating netem cannot exist in a tree with other > netems. We already had one regression scare this week, so given that Cong is not relenting I'll do the unusual thing of parking this fix in net-next. It will reach Linus during the merge window, hopefully the <2 week delay is not a big deal given how long we've taken already.