From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-oi1-f182.google.com (mail-oi1-f182.google.com [209.85.167.182]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 22E7C2F49F1 for ; Tue, 10 Mar 2026 14:55:29 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.167.182 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773154530; cv=none; b=WC3OAeEufmfvtgSV36k0uyy2OIFRndd0rcZ3P+iaGEisQyWh+om63RizuDVBccBIIHu5V9okalb8mfUjDMgjZRT+aMO+pBVFqm+QV45TG/6XVM6hLSueGsLxyJv8dgZ+euo8m+HS9+1vAq1Y2wFuHSdZgLvDC65HK7WXilHCG18= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773154530; c=relaxed/simple; bh=YIo57N2vcHVypstNB2cXBU3r9AT7FE4ZbnUQ6vqutMU=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=AwIdBGFJpea01RmIQd082dEiY7XCIgPQOvN/+X3rzzCBcj1OsRw6h2fwH81aKR34qXeMSNCNjzAmmCqqLF2mGrDnP9XuI71cfcJ+IBoGy3be1b99uH8KiBPbn9baGtfJuwGXSVXmahspGO1iBuhOMEG6Xjd7lQFUgQiVAU7+8Js= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=kernel.dk; spf=pass smtp.mailfrom=kernel.dk; dkim=pass (2048-bit key) header.d=kernel-dk.20230601.gappssmtp.com header.i=@kernel-dk.20230601.gappssmtp.com header.b=Ui5Fef64; arc=none smtp.client-ip=209.85.167.182 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=kernel.dk Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=kernel.dk Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel-dk.20230601.gappssmtp.com header.i=@kernel-dk.20230601.gappssmtp.com header.b="Ui5Fef64" Received: by mail-oi1-f182.google.com with SMTP id 5614622812f47-4648447e29bso4829490b6e.0 for ; Tue, 10 Mar 2026 07:55:28 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel-dk.20230601.gappssmtp.com; s=20230601; t=1773154528; x=1773759328; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=UT/m7GaBXVbUKRMg37ABmfjMs9kKM0kDkv8WvMSyIRg=; b=Ui5Fef64Y7cc1vXZ2PqSKmIZVxSdRCWkS0Lg6mwe1iUfsq9KANbRNCnZ/FMQJMxATj QHFymeG9Tl/r1HOMgPXJreePTXYCip9Stf7oS0jZev52t1jnsEHab6Wq6n3yLTdHpSj8 633geDe8muKV9jVjl6m0Cql/On6hwZW3qRdQArM/jkkWUzUcccHCHAnA+E4shE75h+dS P78+eRjU0w5pQWLWUb8FR7q3XFs7xsbOM5GVVVIWofXYPDJZXxIxhfdAu2HHZh2Hx6PQ ypVIG5HXJPclqZCLo1PTNMH/IXXLkPEde8Nqppi+xd69t9jvfudtTa04goMf2xgYSryh kZ3g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1773154528; x=1773759328; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-gg:x-gm-message-state:from :to:cc:subject:date:message-id:reply-to; bh=UT/m7GaBXVbUKRMg37ABmfjMs9kKM0kDkv8WvMSyIRg=; b=unGki3LisiMi4bbVeCPaWVIDZYQaCLj/wrwcx1ZgxzT5Yr3loOkzGxqJ/YzodFIErX yB3OgHCMLKvNwM+RY9r80B5on7Rb7RM2CSAeqiSvOrReaTgy6Ha0sZ8N51fnw+lyKB01 6ZXo2VWnUfc/Q7IWmxXH/FPK31ZDHmCilk0/sKT2Q3mhFJQK7I9Ho1ooKVWO5Qsbm77g N1aQhZvkUOPMc/FQiQ0GYHlFZMv89J9ZG+76y25tcHUjBDto/XWVVpOiGeWHHHll1Ir0 ocHUCcNd7J+fDhtuZIwLNWLY8sxSZaN7aMbt8xbh15wPp8vkDVbfdA1IwgNue0OLqZfp wWWA== X-Gm-Message-State: AOJu0YxnfC5vff7SpQF7qkmqCgFUqgNJHnAU2W6UY9HpRT/xSg7yVNe1 59hk3yk5KwL8hWDvSwL4ThK8WUuryzG5awaHW1YW5QcvodDxuKtcGLSKEqthw30VkBODMb3oLMO DHmYV3xc= X-Gm-Gg: ATEYQzyOy6QW9jsPSr4ERd7Dpwk7AcKEGxmdenyZj5myVNwshz0EYFFJDQtZmwVXZFs MxdvwRi+4OClL3vIZTajQusJqrCr5DP0wMUhBWZzqQW/+U2wgjAvI+O5CIF+LlMKoQoh+nsMa91 e7iShyL7BWHf6rLEyPFrzPvG7v5zVrYATocd0mI9/rPPZvRCpMUwveAEzC6iT6Gin7lCSM89aoX oKfnkaffGbEP0Jt3zrSdfAS4bwSRmqj3VYKAFHLm55i0utbovtCcKWWVUeW0obvudW9aYK9W/MG giz9ZYnw86F5vyFQ3PKplypQiUNqoZPFt/w40G2G2+LRCoNrPwlTS2g36L5NgJkIB7YtqJJpIfD 4xkioTCeghldBwnVZ/C6p3dLaVXA8OSwg03WZcqg2rfP13dGQVdYlHRSUD78qg3kXfs1Ka8xrrB l/9yv2ZszXogoPzIeUWnKWNU/atq2GlCzs8T/JkqSugKkyTHtpp3XM+h+8n+OZx18DaTqo X-Received: by 2002:a05:6808:c145:b0:467:b0f:997 with SMTP id 5614622812f47-4670b0f13a5mr4283225b6e.34.1773154527823; Tue, 10 Mar 2026 07:55:27 -0700 (PDT) Received: from m2max ([198.8.77.157]) by smtp.gmail.com with ESMTPSA id 5614622812f47-466f429c7fcsm5786865b6e.9.2026.03.10.07.55.27 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 10 Mar 2026 07:55:27 -0700 (PDT) From: Jens Axboe To: io-uring@vger.kernel.org Cc: asml.silence@gmail.com, naup96721@gmail.com, Jens Axboe , stable@vger.kernel.org Subject: [PATCH 2/2] io_uring/eventfd: use ctx->rings_rcu for flags checking Date: Tue, 10 Mar 2026 08:45:49 -0600 Message-ID: <20260310145521.68268-3-axboe@kernel.dk> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260310145521.68268-1-axboe@kernel.dk> References: <20260310145521.68268-1-axboe@kernel.dk> Precedence: bulk X-Mailing-List: io-uring@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Similarly to what commit e78f7b70e837 did for local task work additions, use ->rings_rcu under RCU rather than dereference ->rings directly. See that commit for more details. Cc: stable@vger.kernel.org Fixes: 79cfe9e59c2a ("io_uring/register: add IORING_REGISTER_RESIZE_RINGS") Signed-off-by: Jens Axboe --- io_uring/eventfd.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-) diff --git a/io_uring/eventfd.c b/io_uring/eventfd.c index 78f8ab7db104..ab789e1ebe91 100644 --- a/io_uring/eventfd.c +++ b/io_uring/eventfd.c @@ -76,11 +76,15 @@ void io_eventfd_signal(struct io_ring_ctx *ctx, bool cqe_event) { bool skip = false; struct io_ev_fd *ev_fd; - - if (READ_ONCE(ctx->rings->cq_flags) & IORING_CQ_EVENTFD_DISABLED) - return; + struct io_rings *rings; guard(rcu)(); + + rings = rcu_dereference(ctx->rings_rcu); + if (!rings) + return; + if (READ_ONCE(rings->cq_flags) & IORING_CQ_EVENTFD_DISABLED) + return; ev_fd = rcu_dereference(ctx->io_ev_fd); /* * Check again if ev_fd exists in case an io_eventfd_unregister call -- 2.53.0