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 A86CB20B19 for ; Wed, 20 Sep 2023 11:56:14 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 2BAEBC433C8; Wed, 20 Sep 2023 11:56:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1695210974; bh=1eRRs5MrpOY8nc7Lu0j3x+GS+NqKow5uEZRCgY31twQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=a+x79I109jwiGJg3A09aG44UuX6KVFLhy3f2G4EL2XMj3sqjDYi3OMOshSRxsADLp L7dBv1T8ibtZBNoq6HPyd7bnIstjMEc6rmdLYUic3M8rR94TXHNfgDl4TEjW0+3FyN 26ecY8m3CqCrxKVX7zviqC/CdxuHM+vG+tkxjW50= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, =?UTF-8?q?M=C3=A5rten=20Lindahl?= , "Russell King (Oracle)" , Sasha Levin Subject: [PATCH 6.1 061/139] ARM: 9317/1: kexec: Make smp stop calls asynchronous Date: Wed, 20 Sep 2023 13:29:55 +0200 Message-ID: <20230920112837.972951044@linuxfoundation.org> X-Mailer: git-send-email 2.42.0 In-Reply-To: <20230920112835.549467415@linuxfoundation.org> References: <20230920112835.549467415@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-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 6.1-stable review patch. If anyone has any objections, please let me know. ------------------ From: Mårten Lindahl [ Upstream commit 8922ba71c969d2a0c01a94372a71477d879470de ] If a panic is triggered by a hrtimer interrupt all online cpus will be notified and set offline. But as highlighted by commit 19dbdcb8039c ("smp: Warn on function calls from softirq context") this call should not be made synchronous with disabled interrupts: softdog: Initiating panic Kernel panic - not syncing: Software Watchdog Timer expired WARNING: CPU: 1 PID: 0 at kernel/smp.c:753 smp_call_function_many_cond unwind_backtrace: show_stack dump_stack_lvl __warn warn_slowpath_fmt smp_call_function_many_cond smp_call_function crash_smp_send_stop.part.0 machine_crash_shutdown __crash_kexec panic softdog_fire __hrtimer_run_queues hrtimer_interrupt Make the smp call for machine_crash_nonpanic_core() asynchronous. Signed-off-by: Mårten Lindahl Signed-off-by: Russell King (Oracle) Signed-off-by: Sasha Levin --- arch/arm/kernel/machine_kexec.c | 14 +++++++++++++- 1 file changed, 13 insertions(+), 1 deletion(-) diff --git a/arch/arm/kernel/machine_kexec.c b/arch/arm/kernel/machine_kexec.c index f567032a09c0b..6d1938d1b4df7 100644 --- a/arch/arm/kernel/machine_kexec.c +++ b/arch/arm/kernel/machine_kexec.c @@ -92,16 +92,28 @@ void machine_crash_nonpanic_core(void *unused) } } +static DEFINE_PER_CPU(call_single_data_t, cpu_stop_csd) = + CSD_INIT(machine_crash_nonpanic_core, NULL); + void crash_smp_send_stop(void) { static int cpus_stopped; unsigned long msecs; + call_single_data_t *csd; + int cpu, this_cpu = raw_smp_processor_id(); if (cpus_stopped) return; atomic_set(&waiting_for_crash_ipi, num_online_cpus() - 1); - smp_call_function(machine_crash_nonpanic_core, NULL, false); + for_each_online_cpu(cpu) { + if (cpu == this_cpu) + continue; + + csd = &per_cpu(cpu_stop_csd, cpu); + smp_call_function_single_async(cpu, csd); + } + msecs = 1000; /* Wait at most a second for the other cpus to stop */ while ((atomic_read(&waiting_for_crash_ipi) > 0) && msecs) { mdelay(1); -- 2.40.1