From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from galois.linutronix.de (Galois.linutronix.de [193.142.43.55]) (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 7524136920D; Sat, 30 May 2026 09:38:49 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=193.142.43.55 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780133931; cv=none; b=nhVhFAg/EpK0AwyEB+Q2s5kUiIonXfZdrKKWgXxpxJ9vJy3+LG3KAnptxX1jYErRs7UmI+zUfUjK9B+JSWAWk6hqBY8CREG8u++GFweLoTol6LOzLXKc4PM19JHg+YFcYl40Zlox3xxneSTwmDIwvVjtHwRr3gC9EKVVVOyXHkI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780133931; c=relaxed/simple; bh=pWTLBwiGlrxcyJ+0RK+Ry99mfk6JSH5M0IlflqTGqiM=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=byk8H2F8fci8Oki+wPydYavAh0Uea5L0KU5urCQh4H7BF1PSjh5/S8g/kVk1DuIo7h2uAMcK5Agb6cGmUDbrRSACzYfTjKWbNb7gNjkIvkRNz96mTH1TdcBOgiaQOiFZN3GETdBAHPouVQXWWZ52pu8MXCl5/wo3mwG/6P481Mo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linutronix.de; spf=pass smtp.mailfrom=linutronix.de; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b=TQxDAuJN; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b=S7Z9AnG/; arc=none smtp.client-ip=193.142.43.55 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linutronix.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linutronix.de Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="TQxDAuJN"; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="S7Z9AnG/" From: Nam Cao DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1780133921; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding; bh=FVZrerUcr6b8wyTsKl742IIvubpJCahaogmndvD3sJg=; b=TQxDAuJNZWjcrPpoz5NB/gnDo/0UrB440P4hJDdLCWrb3BsF9sRW9PaPq2Wi1uWXlS89h8 uExb6C+O5RKRFHEZB1Gro7FxGuc2IQkULEMJKmWzuurNbsZhC3sYLObCTTAJBsUjk3twZg vbkda7eeKitRiFTTVCfeFTUIyYlgKNWMk/2bo9Cq9rsEZza9H3WF0vJuVSSt4KSozZTixa pPas16k/CEofUitc+O3Xe4oyxm797LKlc1/RH2rUAxJvKIkekvo8YT5p26Mc44ES+uu8PR EwRapVqYRM8qfejxHWAjMrIc8882WOQX2e+nZIQR4fopWMCp+RmjLryBkKh+/g== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1780133921; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding; bh=FVZrerUcr6b8wyTsKl742IIvubpJCahaogmndvD3sJg=; b=S7Z9AnG/pcQf4DHHQL3nD1mCArjgMGlTJ0laoqP/fY7upY+vImkh6EJ1ydMLqx/6XFZ2ca NlAdMvE2ULYr9TBg== To: Christian Brauner , Alexander Viro , Jan Kara , Shuah Khan , Davidlohr Bueso , Soheil Hassas Yeganeh , Mateusz Guzik , David Laight , linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org Cc: Nam Cao Subject: [PATCH v2 0/2] eventpoll: Fix epoll_wait() report false negative Date: Sat, 30 May 2026 11:37:30 +0200 Message-ID: Precedence: bulk X-Mailing-List: linux-kselftest@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Hi, While staring at epoll, I noticed ep_events_available() looks wrong. I wrote a small program to confirm, and yes it is definitely wrong. This series adds a reproducer to kselftest, and fix the bug. v2: Switch to seqlock solution Nam Cao (2): selftests/eventpoll: Add test for multiple waiters eventpoll: Fix epoll_wait() report false negative fs/eventpoll.c | 20 ++++++++- .../filesystems/epoll/epoll_wakeup_test.c | 45 +++++++++++++++++++ 2 files changed, 64 insertions(+), 1 deletion(-) --=20 2.47.3