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Mon, 09 Nov 2026 10:28:11 -0800 (PST) Received: from localhost ([153.61.198.255]) by smtp.gmail.com with ESMTPSA id 98e67ed59e1d1-3b16769c195sm505135a91.3.2026.11.09.10.28.10 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Mon, 09 Nov 2026 10:28:10 -0800 (PST) Content-Type: text/plain; charset=UTF-8 Date: Mon, 09 Nov 2026 18:28:10 +0000 Message-Id: Cc: , , , , , , , , , , , , Subject: Re: [PATCH bpf 1/2] bpf: Reject user ringbuf backlogs larger than total ring size From: "Alexei Starovoitov" To: "Ren Wei" , In-Reply-To: References: Content-Transfer-Encoding: 8bit X-Mailing-List: bpf@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 On Sun, Nov 08, 2026 at 07:03 PM Ren Wei wrote: > When bpf_user_ringbuf_drain() drains the ring buffer, cons_pos wraps > around the physical buffer repeatedly within the oversized unread window, > replaying stale or already-consumed samples without new writes from user > space. In the worst case, this leads to excessive CPU consumption and > watchdog softlockups. No. Stop the slop pw-bot: cr