From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5774CC4321E for ; Mon, 9 May 2022 13:10:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235259AbiEINOp (ORCPT ); Mon, 9 May 2022 09:14:45 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52916 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235184AbiEINOn (ORCPT ); Mon, 9 May 2022 09:14:43 -0400 Received: from fanzine2.igalia.com (fanzine.igalia.com [178.60.130.6]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0B97322519; Mon, 9 May 2022 06:10:47 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=igalia.com; s=20170329; h=Content-Transfer-Encoding:Content-Type:In-Reply-To:From: References:Cc:To:Subject:MIME-Version:Date:Message-ID:Sender:Reply-To: Content-ID:Content-Description:Resent-Date:Resent-From:Resent-Sender: Resent-To:Resent-Cc:Resent-Message-ID:List-Id:List-Help:List-Unsubscribe: List-Subscribe:List-Post:List-Owner:List-Archive; bh=c6E44QfcLWCPcpfVVn8DZm/tazb9qDNjecxU8jgjjwM=; b=JQ1X+XDjDPRoAxPLkbe9tWes8w l11iC7oa/HVnyRK3qB7UvK9JEgQqPIREqD5654T0lMLes3kGheOm/R45s0nxu4hyBPxmCTVnzlJkN ZvlwDaZFuWVIh4IaLUzoP+QdJvpm215SH2+0rVomODoRdVpIAavgxOQl3rDnkTMN+fyPnfNOV7B7S PwRkKHJor0sF94EKnip9+x+OMSUvYBWlrOB2NiCodRGVM8ztswBp00gdyDLuMLY0TLuRV/nOMh+Z7 dku4FKzrs/p9E3LkAgwz4nFi/oHL/EcQWXaMAdDUro5POIL0/IvuDCL2llWo8K6mm9F1PYJhGhMV8 hibQS8tw==; Received: from [177.183.162.244] (helo=[192.168.0.5]) by fanzine2.igalia.com with esmtpsa (Cipher TLS1.3:ECDHE_X25519__RSA_PSS_RSAE_SHA256__AES_128_GCM:128) (Exim) id 1no39b-0005V6-KV; Mon, 09 May 2022 15:10:24 +0200 Message-ID: <65f24bc5-2211-0139-ee12-b2608e81ceb1@igalia.com> Date: Mon, 9 May 2022 10:09:21 -0300 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.8.1 Subject: Re: [PATCH 09/30] coresight: cpu-debug: Replace mutex with mutex_trylock on panic notifier Content-Language: en-US To: Suzuki K Poulose , akpm@linux-foundation.org, bhe@redhat.com, pmladek@suse.com, kexec@lists.infradead.org Cc: linux-kernel@vger.kernel.org, bcm-kernel-feedback-list@broadcom.com, coresight@lists.linaro.org, linuxppc-dev@lists.ozlabs.org, linux-alpha@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-edac@vger.kernel.org, linux-hyperv@vger.kernel.org, linux-leds@vger.kernel.org, linux-mips@vger.kernel.org, linux-parisc@vger.kernel.org, linux-pm@vger.kernel.org, linux-remoteproc@vger.kernel.org, linux-s390@vger.kernel.org, linux-tegra@vger.kernel.org, linux-um@lists.infradead.org, linux-xtensa@linux-xtensa.org, netdev@vger.kernel.org, openipmi-developer@lists.sourceforge.net, rcu@vger.kernel.org, sparclinux@vger.kernel.org, xen-devel@lists.xenproject.org, x86@kernel.org, kernel-dev@igalia.com, kernel@gpiccoli.net, halves@canonical.com, fabiomirmar@gmail.com, alejandro.j.jimenez@oracle.com, andriy.shevchenko@linux.intel.com, arnd@arndb.de, bp@alien8.de, corbet@lwn.net, d.hatayama@jp.fujitsu.com, dave.hansen@linux.intel.com, dyoung@redhat.com, feng.tang@intel.com, gregkh@linuxfoundation.org, mikelley@microsoft.com, hidehiro.kawai.ez@hitachi.com, jgross@suse.com, john.ogness@linutronix.de, keescook@chromium.org, luto@kernel.org, mhiramat@kernel.org, mingo@redhat.com, paulmck@kernel.org, peterz@infradead.org, rostedt@goodmis.org, senozhatsky@chromium.org, stern@rowland.harvard.edu, tglx@linutronix.de, vgoyal@redhat.com, vkuznets@redhat.com, will@kernel.org, Leo Yan , Mathieu Poirier , Mike Leach References: <20220427224924.592546-1-gpiccoli@igalia.com> <20220427224924.592546-10-gpiccoli@igalia.com> <3cafe4fd-8a0b-2633-44a3-2995abd6c38c@arm.com> From: "Guilherme G. Piccoli" In-Reply-To: <3cafe4fd-8a0b-2633-44a3-2995abd6c38c@arm.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-remoteproc@vger.kernel.org On 28/04/2022 05:11, Suzuki K Poulose wrote: > Hi Guilherme, > > On 27/04/2022 23:49, Guilherme G. Piccoli wrote: >> The panic notifier infrastructure executes registered callbacks when >> a panic event happens - such callbacks are executed in atomic context, >> with interrupts and preemption disabled in the running CPU and all other >> CPUs disabled. That said, mutexes in such context are not a good idea. >> >> This patch replaces a regular mutex with a mutex_trylock safer approach; >> given the nature of the mutex used in the driver, it should be pretty >> uncommon being unable to acquire such mutex in the panic path, hence >> no functional change should be observed (and if it is, that would be >> likely a deadlock with the regular mutex). >> >> Fixes: 2227b7c74634 ("coresight: add support for CPU debug module") >> Cc: Leo Yan >> Cc: Mathieu Poirier >> Cc: Mike Leach >> Cc: Suzuki K Poulose >> Signed-off-by: Guilherme G. Piccoli > > How would you like to proceed with queuing this ? I am happy > either way. In case you plan to push this as part of this > series (I don't see any potential conflicts) : > > Reviewed-by: Suzuki K Poulose Hi Suzuki, some other maintainers are taking the patches to their next branches for example. I'm working on V2, and I guess in the end would be nice to reduce the size of the series a bit. So, do you think you could pick this one for your coresight/next branch (or even for rc cycle, your call - this is really a fix)? This way, I won't re-submit this one in V2, since it's gonna be merged already in your branch. Thanks in advance, Guilherme From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from lists.ozlabs.org (lists.ozlabs.org [112.213.38.117]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 43690C433F5 for ; Mon, 9 May 2022 23:59:45 +0000 (UTC) Received: from boromir.ozlabs.org (localhost [IPv6:::1]) by lists.ozlabs.org (Postfix) with ESMTP id 4Kxyp76qM2z3cg4 for ; Tue, 10 May 2022 09:59:43 +1000 (AEST) Authentication-Results: lists.ozlabs.org; dkim=fail reason="signature verification failed" (2048-bit key; unprotected) header.d=igalia.com header.i=@igalia.com header.a=rsa-sha256 header.s=20170329 header.b=JQ1X+XDj; dkim-atps=neutral Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=igalia.com (client-ip=178.60.130.6; helo=fanzine2.igalia.com; envelope-from=gpiccoli@igalia.com; receiver=) Authentication-Results: lists.ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=igalia.com header.i=@igalia.com header.a=rsa-sha256 header.s=20170329 header.b=JQ1X+XDj; dkim-atps=neutral Received: from fanzine2.igalia.com (fanzine.igalia.com [178.60.130.6]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange ECDHE (P-256) server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 4KxhPY2DJQz3bcW for ; Mon, 9 May 2022 23:10:53 +1000 (AEST) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=igalia.com; s=20170329; h=Content-Transfer-Encoding:Content-Type:In-Reply-To:From: References:Cc:To:Subject:MIME-Version:Date:Message-ID:Sender:Reply-To: Content-ID:Content-Description:Resent-Date:Resent-From:Resent-Sender: Resent-To:Resent-Cc:Resent-Message-ID:List-Id:List-Help:List-Unsubscribe: List-Subscribe:List-Post:List-Owner:List-Archive; bh=c6E44QfcLWCPcpfVVn8DZm/tazb9qDNjecxU8jgjjwM=; b=JQ1X+XDjDPRoAxPLkbe9tWes8w l11iC7oa/HVnyRK3qB7UvK9JEgQqPIREqD5654T0lMLes3kGheOm/R45s0nxu4hyBPxmCTVnzlJkN ZvlwDaZFuWVIh4IaLUzoP+QdJvpm215SH2+0rVomODoRdVpIAavgxOQl3rDnkTMN+fyPnfNOV7B7S PwRkKHJor0sF94EKnip9+x+OMSUvYBWlrOB2NiCodRGVM8ztswBp00gdyDLuMLY0TLuRV/nOMh+Z7 dku4FKzrs/p9E3LkAgwz4nFi/oHL/EcQWXaMAdDUro5POIL0/IvuDCL2llWo8K6mm9F1PYJhGhMV8 hibQS8tw==; Received: from [177.183.162.244] (helo=[192.168.0.5]) by fanzine2.igalia.com with esmtpsa (Cipher TLS1.3:ECDHE_X25519__RSA_PSS_RSAE_SHA256__AES_128_GCM:128) (Exim) id 1no39b-0005V6-KV; Mon, 09 May 2022 15:10:24 +0200 Message-ID: <65f24bc5-2211-0139-ee12-b2608e81ceb1@igalia.com> Date: Mon, 9 May 2022 10:09:21 -0300 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.8.1 Subject: Re: [PATCH 09/30] coresight: cpu-debug: Replace mutex with mutex_trylock on panic notifier Content-Language: en-US To: Suzuki K Poulose , akpm@linux-foundation.org, bhe@redhat.com, pmladek@suse.com, kexec@lists.infradead.org References: <20220427224924.592546-1-gpiccoli@igalia.com> <20220427224924.592546-10-gpiccoli@igalia.com> <3cafe4fd-8a0b-2633-44a3-2995abd6c38c@arm.com> From: "Guilherme G. Piccoli" In-Reply-To: <3cafe4fd-8a0b-2633-44a3-2995abd6c38c@arm.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Mailman-Approved-At: Tue, 10 May 2022 09:58:00 +1000 X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-hyperv@vger.kernel.org, halves@canonical.com, gregkh@linuxfoundation.org, peterz@infradead.org, alejandro.j.jimenez@oracle.com, linux-remoteproc@vger.kernel.org, feng.tang@intel.com, linux-mips@vger.kernel.org, hidehiro.kawai.ez@hitachi.com, sparclinux@vger.kernel.org, will@kernel.org, tglx@linutronix.de, linux-leds@vger.kernel.org, linux-s390@vger.kernel.org, mikelley@microsoft.com, john.ogness@linutronix.de, corbet@lwn.net, paulmck@kernel.org, fabiomirmar@gmail.com, x86@kernel.org, mingo@redhat.com, bcm-kernel-feedback-list@broadcom.com, xen-devel@lists.xenproject.org, dyoung@redhat.com, vgoyal@redhat.com, Mike Leach , linux-xtensa@linux-xtensa.org, dave.hansen@linux.intel.com, keescook@chromium.org, arnd@arndb.de, linux-pm@vger.kernel.org, coresight@lists.linaro.org, Leo Yan , linux-um@lists.infradead.org, rostedt@goodmis.org, rcu@vger.kernel.org, bp@alien8.de, luto@kernel.org, linux-tegra@vger.kernel.org, openipmi-developer@lists.sourceforge.net, andriy.shevchenko@linux.intel.com, linux-arm-kernel@lists.infradead.org, linux-edac@vger.kernel.org, jgross@suse.com, Mathieu Poirier , linux-parisc@vger.kernel.org, netdev@vger.kernel.org, kernel@gpiccoli.net, linux-kernel@vger.kernel.org, stern@rowland.harvard.edu, senozhatsky@chromium.org, d.hatayama@jp.fujitsu.com, mhiramat@kernel.org, kernel-dev@igalia.com, linux-alpha@vger.kernel.org, vkuznets@redhat.com, linuxppc-dev@lists.ozlabs.org Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" On 28/04/2022 05:11, Suzuki K Poulose wrote: > Hi Guilherme, > > On 27/04/2022 23:49, Guilherme G. Piccoli wrote: >> The panic notifier infrastructure executes registered callbacks when >> a panic event happens - such callbacks are executed in atomic context, >> with interrupts and preemption disabled in the running CPU and all other >> CPUs disabled. That said, mutexes in such context are not a good idea. >> >> This patch replaces a regular mutex with a mutex_trylock safer approach; >> given the nature of the mutex used in the driver, it should be pretty >> uncommon being unable to acquire such mutex in the panic path, hence >> no functional change should be observed (and if it is, that would be >> likely a deadlock with the regular mutex). >> >> Fixes: 2227b7c74634 ("coresight: add support for CPU debug module") >> Cc: Leo Yan >> Cc: Mathieu Poirier >> Cc: Mike Leach >> Cc: Suzuki K Poulose >> Signed-off-by: Guilherme G. Piccoli > > How would you like to proceed with queuing this ? I am happy > either way. In case you plan to push this as part of this > series (I don't see any potential conflicts) : > > Reviewed-by: Suzuki K Poulose Hi Suzuki, some other maintainers are taking the patches to their next branches for example. I'm working on V2, and I guess in the end would be nice to reduce the size of the series a bit. So, do you think you could pick this one for your coresight/next branch (or even for rc cycle, your call - this is really a fix)? This way, I won't re-submit this one in V2, since it's gonna be merged already in your branch. Thanks in advance, Guilherme From mboxrd@z Thu Jan 1 00:00:00 1970 From: Guilherme G. Piccoli Date: Mon, 9 May 2022 10:09:21 -0300 Subject: [PATCH 09/30] coresight: cpu-debug: Replace mutex with mutex_trylock on panic notifier In-Reply-To: <3cafe4fd-8a0b-2633-44a3-2995abd6c38c@arm.com> References: <20220427224924.592546-1-gpiccoli@igalia.com> <20220427224924.592546-10-gpiccoli@igalia.com> <3cafe4fd-8a0b-2633-44a3-2995abd6c38c@arm.com> Message-ID: <65f24bc5-2211-0139-ee12-b2608e81ceb1@igalia.com> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: kexec@lists.infradead.org On 28/04/2022 05:11, Suzuki K Poulose wrote: > Hi Guilherme, > > On 27/04/2022 23:49, Guilherme G. Piccoli wrote: >> The panic notifier infrastructure executes registered callbacks when >> a panic event happens - such callbacks are executed in atomic context, >> with interrupts and preemption disabled in the running CPU and all other >> CPUs disabled. That said, mutexes in such context are not a good idea. >> >> This patch replaces a regular mutex with a mutex_trylock safer approach; >> given the nature of the mutex used in the driver, it should be pretty >> uncommon being unable to acquire such mutex in the panic path, hence >> no functional change should be observed (and if it is, that would be >> likely a deadlock with the regular mutex). >> >> Fixes: 2227b7c74634 ("coresight: add support for CPU debug module") >> Cc: Leo Yan >> Cc: Mathieu Poirier >> Cc: Mike Leach >> Cc: Suzuki K Poulose >> Signed-off-by: Guilherme G. Piccoli > > How would you like to proceed with queuing this ? I am happy > either way. In case you plan to push this as part of this > series (I don't see any potential conflicts) : > > Reviewed-by: Suzuki K Poulose Hi Suzuki, some other maintainers are taking the patches to their next branches for example. I'm working on V2, and I guess in the end would be nice to reduce the size of the series a bit. So, do you think you could pick this one for your coresight/next branch (or even for rc cycle, your call - this is really a fix)? This way, I won't re-submit this one in V2, since it's gonna be merged already in your branch. Thanks in advance, Guilherme From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Message-ID: <65f24bc5-2211-0139-ee12-b2608e81ceb1@igalia.com> Date: Mon, 9 May 2022 10:09:21 -0300 MIME-Version: 1.0 Subject: Re: [PATCH 09/30] coresight: cpu-debug: Replace mutex with mutex_trylock on panic notifier Content-Language: en-US References: <20220427224924.592546-1-gpiccoli@igalia.com> <20220427224924.592546-10-gpiccoli@igalia.com> <3cafe4fd-8a0b-2633-44a3-2995abd6c38c@arm.com> From: "Guilherme G. Piccoli" In-Reply-To: <3cafe4fd-8a0b-2633-44a3-2995abd6c38c@arm.com> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-um" Errors-To: linux-um-bounces+geert=linux-m68k.org@lists.infradead.org To: Suzuki K Poulose , akpm@linux-foundation.org, bhe@redhat.com, pmladek@suse.com, kexec@lists.infradead.org Cc: linux-kernel@vger.kernel.org, bcm-kernel-feedback-list@broadcom.com, coresight@lists.linaro.org, linuxppc-dev@lists.ozlabs.org, linux-alpha@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-edac@vger.kernel.org, linux-hyperv@vger.kernel.org, linux-leds@vger.kernel.org, linux-mips@vger.kernel.org, linux-parisc@vger.kernel.org, linux-pm@vger.kernel.org, linux-remoteproc@vger.kernel.org, linux-s390@vger.kernel.org, linux-tegra@vger.kernel.org, linux-um@lists.infradead.org, linux-xtensa@linux-xtensa.org, netdev@vger.kernel.org, openipmi-developer@lists.sourceforge.net, rcu@vger.kernel.org, sparclinux@vger.kernel.org, xen-devel@lists.xenproject.org, x86@kernel.org, kernel-dev@igalia.com, kernel@gpiccoli.net, halves@canonical.com, fabiomirmar@gmail.com, alejandro.j.jimenez@oracle.com, andriy.shevchenko@linux.intel.com, arnd@arndb.de, bp@alien8.de, corbet@lwn.net, d.hatayama@jp.fujitsu.com, dave.hansen@linux.intel.com, dyoung@redhat.com, feng.tang@intel.com, gregkh@linuxfoundation.org, mikelley@microsoft.com, hidehiro.kawai.ez@hitachi.com, jgross@suse.com, john.ogness@linutronix.de, keescook@chromium.org, luto@kernel.org, mhiramat@kernel.org, mingo@redhat.com, paulmck@kernel.org, peterz@infradead.org, rostedt@goodmis.org, senozhatsky@chromium.org, stern@rowland.harvard.edu, tglx@linutronix.de, vgoyal@redhat.com, vkuznets@redhat.com, will@kernel.org, Leo Yan , Mathieu Poirier , Mike Leach On 28/04/2022 05:11, Suzuki K Poulose wrote: > Hi Guilherme, > > On 27/04/2022 23:49, Guilherme G. Piccoli wrote: >> The panic notifier infrastructure executes registered callbacks when >> a panic event happens - such callbacks are executed in atomic context, >> with interrupts and preemption disabled in the running CPU and all other >> CPUs disabled. That said, mutexes in such context are not a good idea. >> >> This patch replaces a regular mutex with a mutex_trylock safer approach; >> given the nature of the mutex used in the driver, it should be pretty >> uncommon being unable to acquire such mutex in the panic path, hence >> no functional change should be observed (and if it is, that would be >> likely a deadlock with the regular mutex). >> >> Fixes: 2227b7c74634 ("coresight: add support for CPU debug module") >> Cc: Leo Yan >> Cc: Mathieu Poirier >> Cc: Mike Leach >> Cc: Suzuki K Poulose >> Signed-off-by: Guilherme G. Piccoli > > How would you like to proceed with queuing this ? I am happy > either way. In case you plan to push this as part of this > series (I don't see any potential conflicts) : > > Reviewed-by: Suzuki K Poulose Hi Suzuki, some other maintainers are taking the patches to their next branches for example. I'm working on V2, and I guess in the end would be nice to reduce the size of the series a bit. So, do you think you could pick this one for your coresight/next branch (or even for rc cycle, your call - this is really a fix)? This way, I won't re-submit this one in V2, since it's gonna be merged already in your branch. Thanks in advance, Guilherme _______________________________________________ linux-um mailing list linux-um@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-um From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Guilherme G. Piccoli" Subject: Re: [PATCH 09/30] coresight: cpu-debug: Replace mutex with mutex_trylock on panic notifier Date: Mon, 9 May 2022 10:09:21 -0300 Message-ID: <65f24bc5-2211-0139-ee12-b2608e81ceb1@igalia.com> References: <20220427224924.592546-1-gpiccoli@igalia.com> <20220427224924.592546-10-gpiccoli@igalia.com> <3cafe4fd-8a0b-2633-44a3-2995abd6c38c@arm.com> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Return-path: DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=igalia.com; s=20170329; h=Content-Transfer-Encoding:Content-Type:In-Reply-To:From: References:Cc:To:Subject:MIME-Version:Date:Message-ID:Sender:Reply-To: Content-ID:Content-Description:Resent-Date:Resent-From:Resent-Sender: Resent-To:Resent-Cc:Resent-Message-ID:List-Id:List-Help:List-Unsubscribe: List-Subscribe:List-Post:List-Owner:List-Archive; bh=c6E44QfcLWCPcpfVVn8DZm/tazb9qDNjecxU8jgjjwM=; b=JQ1X+XDjDPRoAxPLkbe9tWes8w l11iC7oa/HVnyRK3qB7UvK9JEgQqPIREqD5654T0lMLes3kGheOm/R45s0nxu4hyBPxmCTVnzlJkN ZvlwDaZFuWVIh4IaLUzoP+QdJvpm215SH2+0rVomODoRdVpIAavgxOQl3rDnkTMN+fyPnfNOV7B7S PwRkKHJor0sF94EKnip9+x+OMSUvYBWlrOB2NiCodRGVM8ztswBp00gdyDLuMLY0TLuRV/nOMh+Z7 dku4FKzrs/p9E3LkAgwz4nFi/oHL/EcQWXaMAdDUro5POIL0/IvuDCL2llWo8K6mm9F1PYJhGhMV8 hibQS8t Content-Language: en-US In-Reply-To: <3cafe4fd-8a0b-2633-44a3-2995abd6c38c-5wv7dgnIgG8@public.gmane.org> List-ID: Content-Type: text/plain; charset="us-ascii" To: Suzuki K Poulose , akpm-de/tnXTf+JLsfHDXvbKv3WD2FQJk+8+b@public.gmane.org, bhe-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org, pmladek-IBi9RG/b67k@public.gmane.org, kexec-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org Cc: linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, bcm-kernel-feedback-list-dY08KVG/lbpWk0Htik3J/w@public.gmane.org, coresight-cunTk1MwBs8s++Sfvej+rw@public.gmane.org, linuxppc-dev-uLR06cmDAlY/bJ5BZ2RsiQ@public.gmane.org, linux-alpha-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, linux-edac-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-hyperv-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-leds-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-mips-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-parisc-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-pm-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-remoteproc-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-s390-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-tegra-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-um-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, linux-xtensa-PjhNF2WwrV/0Sa2dR60CXw@public.gmane.org, netdev-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, openipmi-developer-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org, rcu-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, sparclinux-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, xen-devel-GuqFBffKawtpuQazS67q72D2FQJk+8+b@public.gmane.org, x86-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org, kernel-dev-wEGTBA9jqPzQT0dZR+AlfA@public.gmane.org, kernel-WeLdAqEWwDvk1uMJSBkQmQ@public.gmane.org, halves-Z7WLFzj8eWMS+FvcfC7Uqw@public.gmane.org, fabiomirmar-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org, alejandro.j.jimenez@ora On 28/04/2022 05:11, Suzuki K Poulose wrote: > Hi Guilherme, > > On 27/04/2022 23:49, Guilherme G. Piccoli wrote: >> The panic notifier infrastructure executes registered callbacks when >> a panic event happens - such callbacks are executed in atomic context, >> with interrupts and preemption disabled in the running CPU and all other >> CPUs disabled. That said, mutexes in such context are not a good idea. >> >> This patch replaces a regular mutex with a mutex_trylock safer approach; >> given the nature of the mutex used in the driver, it should be pretty >> uncommon being unable to acquire such mutex in the panic path, hence >> no functional change should be observed (and if it is, that would be >> likely a deadlock with the regular mutex). >> >> Fixes: 2227b7c74634 ("coresight: add support for CPU debug module") >> Cc: Leo Yan >> Cc: Mathieu Poirier >> Cc: Mike Leach >> Cc: Suzuki K Poulose >> Signed-off-by: Guilherme G. Piccoli > > How would you like to proceed with queuing this ? I am happy > either way. In case you plan to push this as part of this > series (I don't see any potential conflicts) : > > Reviewed-by: Suzuki K Poulose Hi Suzuki, some other maintainers are taking the patches to their next branches for example. I'm working on V2, and I guess in the end would be nice to reduce the size of the series a bit. So, do you think you could pick this one for your coresight/next branch (or even for rc cycle, your call - this is really a fix)? This way, I won't re-submit this one in V2, since it's gonna be merged already in your branch. Thanks in advance, Guilherme