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 9FBA026A0AF; Tue, 8 Apr 2025 12:06:17 +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=1744113977; cv=none; b=A6apXcy2dHQkr9ch3Qbi0WkRRzMrPgfx9K/OkO5bBJcOTo79WUhTVfQhJf/eppRSF8HSm7T+jpzR5osHD2j/h1VlB6pceXXtkjMx1XJnYoiIud5hAu8UTLEKSSAuxs6ChmzJTgocZyXf7Ms5eu5jO0AZaw06fI8XKjqx2PIUJyg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1744113977; c=relaxed/simple; bh=thZ1sDa82j6aQbYRVLZyh3ppDUGKJmShqmIXYxpkdD0=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=V+EEaFrsYxVNg0Z2CcMpfSKcPzy0JfyzpaJ9IuU89ABQfDROWypQ+303cWx+QbrkzsKNuUggBffrXJ4PjhUyzLJhxA6W6sIv52TEjwAERYBpGwyQ7gBn6fLd/ppfJqRuk6loNjF2NPT3sTiNQOjm3GqFTGYL+OfFRMszXq8vkT0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=KbGkJvuL; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="KbGkJvuL" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 316D5C4CEE5; Tue, 8 Apr 2025 12:06:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1744113977; bh=thZ1sDa82j6aQbYRVLZyh3ppDUGKJmShqmIXYxpkdD0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=KbGkJvuLXdhFYRKmT5uG3d8Up0SzCQljgIh8o/RVjg+CSUZMRunX2CfK5naaGdu+o nA7wKvdlHgJObMSdrWFIi8jdPq8GNgDVE6FvyzWFiL8Eu69mfMJoEcZClxHW4EkrGg Py5keXJAs/3W/bWiENFOlkSgUzqEM59aJg5cWNFc= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Tao Chen , Ingo Molnar , Peter Zijlstra , Arnaldo Carvalho de Melo , "H. Peter Anvin" , Linus Torvalds , Sasha Levin Subject: [PATCH 5.4 091/154] perf/ring_buffer: Allow the EPOLLRDNORM flag for poll Date: Tue, 8 Apr 2025 12:50:32 +0200 Message-ID: <20250408104818.239417254@linuxfoundation.org> X-Mailer: git-send-email 2.49.0 In-Reply-To: <20250408104815.295196624@linuxfoundation.org> References: <20250408104815.295196624@linuxfoundation.org> User-Agent: quilt/0.68 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 5.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Tao Chen [ Upstream commit c96fff391c095c11dc87dab35be72dee7d217cde ] The poll man page says POLLRDNORM is equivalent to POLLIN. For poll(), it seems that if user sets pollfd with POLLRDNORM in userspace, perf_poll will not return until timeout even if perf_output_wakeup called, whereas POLLIN returns. Fixes: 76369139ceb9 ("perf: Split up buffer handling from core code") Signed-off-by: Tao Chen Signed-off-by: Ingo Molnar Cc: Peter Zijlstra Cc: Arnaldo Carvalho de Melo Cc: "H. Peter Anvin" Cc: Linus Torvalds Link: https://lore.kernel.org/r/20250314030036.2543180-1-chen.dylane@linux.dev Signed-off-by: Sasha Levin --- kernel/events/ring_buffer.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/events/ring_buffer.c b/kernel/events/ring_buffer.c index 679cc87b40f4b..0611477e4dadd 100644 --- a/kernel/events/ring_buffer.c +++ b/kernel/events/ring_buffer.c @@ -19,7 +19,7 @@ static void perf_output_wakeup(struct perf_output_handle *handle) { - atomic_set(&handle->rb->poll, EPOLLIN); + atomic_set(&handle->rb->poll, EPOLLIN | EPOLLRDNORM); handle->event->pending_wakeup = 1; irq_work_queue(&handle->event->pending); -- 2.39.5