From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Alex G." Subject: Re: [RFC PATCH v2 3/4] acpi: apei: Do not panic() when correctable errors are marked as fatal. Date: Thu, 19 Apr 2018 11:27:52 -0500 Message-ID: References: <20180416215903.7318-1-mr.nuke.me@gmail.com> <20180416215903.7318-4-mr.nuke.me@gmail.com> <20180418175415.GJ4795@pd.tnic> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: Content-Language: en-US Sender: linux-kernel-owner@vger.kernel.org To: James Morse Cc: Borislav Petkov , linux-acpi@vger.kernel.org, linux-edac@vger.kernel.org, rjw@rjwysocki.net, lenb@kernel.org, tony.luck@intel.com, tbaicar@codeaurora.org, will.deacon@arm.com, shiju.jose@huawei.com, zjzhang@codeaurora.org, gengdongjiu@huawei.com, linux-kernel@vger.kernel.org, alex_gagniuc@dellteam.com, austin_bolen@dell.com, shyam_iyer@dell.com, devel@acpica.org, mchehab@kernel.org, robert.moore@intel.com, erik.schmauss@intel.com List-Id: linux-acpi@vger.kernel.org On 04/19/2018 10:35 AM, James Morse wrote: > Hi Alex, > > (I haven't read through all this yet, just on this one:) > > On 04/19/2018 03:57 PM, Alex G. wrote: >> Maybe it's better move the AER handling to NMI/IRQ context, since >> ghes_handle_aer() is only scheduling the real AER andler, and is irq >> safe. I'm scratching my head about why we're messing with IRQ work from >> NMI context, instead of just scheduling a regular handler to take care >> of things. > > We can't touch schedule_work_on() from NMI context as it takes spinlocks > and > disables interrupts. (see __queue_work()) The NMI may have interrupted > IRQ-context code > that was already holding the same locks. > > IRQ-work behaves differently, it uses an llist for the work and an arch > code hook > to raise a self-IPI. That makes sense. Thank you! Alex > > Thanks, > > James