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 4497119B3FF; Tue, 15 Oct 2024 11:59:14 +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=1728993554; cv=none; b=pmdGA/mQIymZYQuqNAemTT5MWTXnREWjO2di2ZSNNoHab+JiCtbZT98Edw3fwiUeB8PxX5Bwwx/M4GGtuelqx1eRvVo0TxMLUuYVotbdVViZZHGireygnyRdARJdg8lOVR+iy9W8HDRtfXtZPxhrje6Harrj1ToPJk9iSbYyAr8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1728993554; c=relaxed/simple; bh=myBGadC8f3sFZO2G100cEvMFBmX88w6tEu2tvejQpvE=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=pj+y9s5aICEkUjcigYGZRTwNDRkLa7MET3gERZPoCrMFBeCAJJTLBWX6eWXY2TXWmSWzHQ/7HTVim/Ia1JdquPUJvFcI6HQ26BSdWJxxGIC+RSGfOWKVdcwsmDIG/ZeSpwMtZe0/TVUdvYpUW5IUimEx4AV4C88XBt/29m/y61A= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=oxx66o0y; 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="oxx66o0y" Received: by smtp.kernel.org (Postfix) with ESMTPSA id A75F7C4CEC6; Tue, 15 Oct 2024 11:59:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1728993554; bh=myBGadC8f3sFZO2G100cEvMFBmX88w6tEu2tvejQpvE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=oxx66o0yLlZm4BTVilNTrwIQNIzTVMwaM5VVr6G2RLORspJASM+IcJVYzw8xZ5exW Z0vRez+et0QpH22qxFMEAdDIL8bISG024mE2fPD2PATzxEhNzTwSZDxMIjCF+RMcO+ ouet55DIsj9/BwDZUCZ2twVkypNMRe8dw7oP4OL4= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, "Paul E. McKenney" , Neeraj Upadhyay , Sasha Levin Subject: [PATCH 5.15 445/691] rcuscale: Provide clear error when async specified without primitives Date: Tue, 15 Oct 2024 13:26:33 +0200 Message-ID: <20241015112458.009707086@linuxfoundation.org> X-Mailer: git-send-email 2.47.0 In-Reply-To: <20241015112440.309539031@linuxfoundation.org> References: <20241015112440.309539031@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 5.15-stable review patch. If anyone has any objections, please let me know. ------------------ From: Paul E. McKenney [ Upstream commit 11377947b5861fa59bf77c827e1dd7c081842cc9 ] Currently, if the rcuscale module's async module parameter is specified for RCU implementations that do not have async primitives such as RCU Tasks Rude (which now lacks a call_rcu_tasks_rude() function), there will be a series of splats due to calls to a NULL pointer. This commit therefore warns of this situation, but switches to non-async testing. Signed-off-by: "Paul E. McKenney" Signed-off-by: Neeraj Upadhyay Signed-off-by: Sasha Levin --- kernel/rcu/rcuscale.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/kernel/rcu/rcuscale.c b/kernel/rcu/rcuscale.c index a83cb29d37607..f90955dc15327 100644 --- a/kernel/rcu/rcuscale.c +++ b/kernel/rcu/rcuscale.c @@ -428,7 +428,7 @@ rcu_scale_writer(void *arg) udelay(writer_holdoff); wdp = &wdpp[i]; *wdp = ktime_get_mono_fast_ns(); - if (gp_async) { + if (gp_async && !WARN_ON_ONCE(!cur_ops->async)) { retry: if (!rhp) rhp = kmalloc(sizeof(*rhp), GFP_KERNEL); @@ -484,7 +484,7 @@ rcu_scale_writer(void *arg) i++; rcu_scale_wait_shutdown(); } while (!torture_must_stop()); - if (gp_async) { + if (gp_async && cur_ops->async) { cur_ops->gp_barrier(); } writer_n_durations[me] = i_max + 1; -- 2.43.0