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 79CCD1C07FF; Tue, 15 Oct 2024 13:11:59 +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=1728997919; cv=none; b=LAIJZRG2wur6AMzrtXR+AO40EHYn1VtdYHchzhvX3lEHsvDXWKfX+OKkomoBXcEA0mN8vlwTO+wbVganWp8fc5icfew2c5WhEr5TbtrI7GqHJVOl+HrIR5sGaq1UYz0ZKX/gRIBydYFM7199mjm2VeYiEPUfnRNZnVxwO2wOv6w= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1728997919; c=relaxed/simple; bh=UjqbBCNC0Qa+4fNF8ZIGFnCIdvfu1URxP1L8SKepnP0=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=SVQYXJ4REPehVYO8YAMe2hBF5dYw2JhuCUrmkdu7+EJRE3cArEWeHOPAp6r5T3BcCA/xwwjwE2oV3OI1bYjsVKfBZXzd1UBrbm+4CXvPSc/WLtyb3Ic+++m55l7XLKsW5Tnr7SjPUwP/l079rdyV9lNo/IpC17dDcGZm9k4Zn10= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=AYhZWM1N; 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="AYhZWM1N" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 9CBE3C4CECE; Tue, 15 Oct 2024 13:11:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1728997919; bh=UjqbBCNC0Qa+4fNF8ZIGFnCIdvfu1URxP1L8SKepnP0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=AYhZWM1NbXc9bMskmBE3PdbITdI/GJWnTCqoHdEebMlh+M+d/vpMvjCjM5NhS80TX DwLjynGqVGlecaplYFvyWxcBnGLD+yDAYf8hUd41BIWMsB5xAfqiXIA4ZR3B3mGJYz OBUcxwfbKhaJ8WKN5ZEI0st7nXMkwAH2tkrWidWM= 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 5.10 326/518] rcuscale: Provide clear error when async specified without primitives Date: Tue, 15 Oct 2024 14:43:50 +0200 Message-ID: <20241015123929.561803833@linuxfoundation.org> X-Mailer: git-send-email 2.47.0 In-Reply-To: <20241015123916.821186887@linuxfoundation.org> References: <20241015123916.821186887@linuxfoundation.org> User-Agent: quilt/0.67 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 5.10-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 3b9783eda6796..cfe861bac1bd4 100644 --- a/kernel/rcu/rcuscale.c +++ b/kernel/rcu/rcuscale.c @@ -398,7 +398,7 @@ 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); @@ -454,7 +454,7 @@ 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