Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 CB9153446C0 for ; Wed, 9 Sep 2026 19:09:39 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788980981; cv=none; b=tKmTrpaWfSw2/iAFxWNu4mvPRlQQrMFMWJ/yZecpGBhDR7EVWx5f5eqcJSr+bGRoTXkckxA/J7G3JcfiGgc5m6Dn3OwwNah68cbP32bHxX+mCrJ41Ahs0x94NdbIxFkiP8gjTbICAyYwTulGBCpJnEXoP1Y5Q/tGbQswxCd2gj8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788980981; c=relaxed/simple; bh=Fv3YpE8rn69mWc0+unxV7FtgBOidj7x7HoAetoSXXg4=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=PbahvKARTuKgCDqsVe5iz7n7KcilJjrqyYjT+Ek63HwvsuryuDi9WmuHxXdCvFmB8N8C1FzpAQL9nVArm+hPlDKKXuVcgtm93kgHioya6tEOCcNMp1Tae2h6pyqpW89p465TQRfPMIVQV5/2BVxJFWPsOXjZiXuESeZu7oFxw08= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=Wp3Oqo3a; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="Wp3Oqo3a" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 9FD7E1F00899; Wed, 9 Sep 2026 19:09:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1788980979; bh=DJhnqDx16/SgEalbuLaN+0EvsIDfrdAcEFJ4f9IKass=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=Wp3Oqo3a09sHcnPWKXo3W74LLVuidWVEiQRUufbACfsN0tmYoyi05ULlLfN2vIvVE Ph3AvgIdxPe6hBl66TR8CgKRp9DAr/fsqucwblYTZX1/3s/ztpTSOWwsB+bnk7kDxy ADmbt4b6bMzx9Z9MhEDlxAuXLjk2/nDbG7zFeh1nS9oZtMsZkdODZUB5sgZRzb1CwL dlY0TwTD4CXxieh8Owzz/5n2cpfJtKNhihmREM0YnaoeESEKT2y1XM/3+bFJXWwtLA PDKrnSgjc9XIIzDF/eSwtd1zyT2M5KvQMtQtxMZVrRCMTpga9yT2EIVToV8cl1MROo nZAUmMGrPl69w== From: Sasha Levin To: stable@vger.kernel.org Cc: Hidayath Khan , Mahanta Jambigi , Simon Horman , Jakub Kicinski , Sasha Levin Subject: [PATCH 5.15.y 2/2] net/smc: stop killed, freed and out_of_sync sharing a byte Date: Wed, 9 Sep 2026 15:09:35 -0400 Message-ID: <20260909190935.3545815-2-sashal@kernel.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260909190935.3545815-1-sashal@kernel.org> References: <2026090313-litter-deputize-53d5@gregkh> <20260909190935.3545815-1-sashal@kernel.org> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: Hidayath Khan [ Upstream commit db51a8658c11a82432b64999519a269c3aabb447 ] The three connection state flags are single-bit bitfields, so they occupy one byte of struct smc_connection and every store to one is a read-modify-write of the other two: u8 killed : 1; u8 freed : 1; u8 out_of_sync : 1; They are not written under a common lock. smc_cdc_msg_validate() sets out_of_sync from the receive tasklet, while smc_conn_kill() sets killed from process context under lock_sock(), and the receive path does not defer to the backlog when the socket is owned -- smc_cdc_msg_recv() takes only bh_lock_sock(). Give each flag its own byte so a store no longer touches its neighbours. All readers test them as booleans and are unchanged. struct smc_connection grows by two bytes. Fixes: b286a0651e44 ("net/smc: handle incoming CDC validation message") Cc: stable@vger.kernel.org Reviewed-by: Mahanta Jambigi Signed-off-by: Hidayath Khan Reviewed-by: Simon Horman Link: https://patch.msgid.link/20260820074642.966856-2-hidayath@linux.ibm.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- net/smc/smc.h | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/net/smc/smc.h b/net/smc/smc.h index 1153dfaaca71d..aee665bd03f14 100644 --- a/net/smc/smc.h +++ b/net/smc/smc.h @@ -216,9 +216,9 @@ struct smc_connection { * 0 for SMC-R, 32 for SMC-D */ u64 peer_token; /* SMC-D token of peer */ - u8 killed : 1; /* abnormal termination */ - u8 freed : 1; /* normal termination */ - u8 out_of_sync : 1; /* out of sync with peer */ + u8 killed; /* abnormal termination */ + u8 freed; /* normal termination */ + u8 out_of_sync; /* out of sync with peer */ }; struct smc_sock { /* smc sock container */ -- 2.53.0