From nobody Fri Dec 19 18:43:03 2025 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 BEE4D1FEC72; Sun, 24 Mar 2024 23:02:39 +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=1711321360; cv=none; b=R/67ZbPzXpmFzwlLUOmpLyQ8Ffld2mYhvZK8jzHP2ob6dZLjVjYl//XAHLUAv1qJZ6Pz1ZuESMX/8a19ehudDqUOoahRKckZxAJ8eSZoBy9L5DXnvuJ1xrwX3NFUOxl1W7QNmhIYhsndV5ywvNxV6/647ZK1fcnU0EGZyNmX9qg= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1711321360; c=relaxed/simple; bh=07OLBcZWNFpd2dvobb1dW1Ge/9r10M08MOnow2/sVFo=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=bXPdwBV+0PkTsidDDESMyUPYlY16LNh58r638gaDX2RWd5ID3tZ0wqoBhPKwAqS0M4Fi1PkKBmSTRK7dfgR5xymBH3ZdHBsxcaiBuhwJJXl/nB553yHU8ABwvgphKLEGmtf9FE7fxQHAM3GZqaTZMS9O0HEiJ7Od5v4f4upd9nY= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=HFyXFX1E; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="HFyXFX1E" Received: by smtp.kernel.org (Postfix) with ESMTPSA id CF0AAC43399; Sun, 24 Mar 2024 23:02:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1711321359; bh=07OLBcZWNFpd2dvobb1dW1Ge/9r10M08MOnow2/sVFo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=HFyXFX1ESLIrgEVQBuZByfxl47MlcKh8P99mK0TARAmDrds1MNhcwaBLuGM/1DRf3 F7OpDEKXRRspkWql2pHm2BFL9hKmzwsddM3ieS8lm041T2w3CDOU51JQ67V3w81vyl Oq/MLNQ02Gebn7RCWs63z7R/tttuu61qok5xt2Rz1aUdvHuxL2dG8DaD77DIq9ebt9 r/NwLTe64QeUUT9UvFkodKyCVj2IUEGFYMUko9JBzOfmuJXGTe/EGjsJrPguLMSQ4R ymFmtI/h+2a7HN4FjLgWo//lWfjdHPJvDgGkKXfcUgzmt8a8nG5HttoOOTwGedAH1n RSr/SiS99Pgjw== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Frederic Weisbecker , Kalesh Singh , "Paul E . McKenney" , Boqun Feng , Sasha Levin Subject: [PATCH 6.6 084/638] rcu/exp: Fix RCU expedited parallel grace period kworker allocation failure recovery Date: Sun, 24 Mar 2024 18:52:01 -0400 Message-ID: <20240324230116.1348576-85-sashal@kernel.org> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20240324230116.1348576-1-sashal@kernel.org> References: <20240324230116.1348576-1-sashal@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" From: Frederic Weisbecker [ Upstream commit a636c5e6f8fc34be520277e69c7c6ee1d4fc1d17 ] Under CONFIG_RCU_EXP_KTHREAD=3Dy, the nodes initialization for expedited grace periods is queued to a kworker. However if the allocation of that kworker failed, the nodes initialization is performed synchronously by the caller instead. Now the check for kworker initialization failure relies on the kworker pointer to be NULL while its value might actually encapsulate an allocation failure error. Make sure to handle this case. Reviewed-by: Kalesh Singh Fixes: 9621fbee44df ("rcu: Move expedited grace period (GP) work to RT kthr= ead_worker") Signed-off-by: Frederic Weisbecker Reviewed-by: Paul E. McKenney Signed-off-by: Boqun Feng Signed-off-by: Sasha Levin --- kernel/rcu/tree.c | 1 + 1 file changed, 1 insertion(+) diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c index 4fe47ed95eebc..2e8d4572e8620 100644 --- a/kernel/rcu/tree.c +++ b/kernel/rcu/tree.c @@ -4677,6 +4677,7 @@ static void __init rcu_start_exp_gp_kworkers(void) rcu_exp_par_gp_kworker =3D kthread_create_worker(0, par_gp_kworker_name); if (IS_ERR_OR_NULL(rcu_exp_par_gp_kworker)) { pr_err("Failed to create %s!\n", par_gp_kworker_name); + rcu_exp_par_gp_kworker =3D NULL; kthread_destroy_worker(rcu_exp_gp_kworker); return; } --=20 2.43.0