From mboxrd@z Thu Jan 1 00:00:00 1970 From: Borislav Petkov Subject: Re: [PATCH v3 01/22] hardirq/nmi: Allow nested nmi_enter() Date: Wed, 19 Feb 2020 17:56:50 +0100 Message-ID: <20200219165650.GB32346@zn.tnic> References: <20200219144724.800607165@infradead.org> <20200219150744.428764577@infradead.org> <20200219103126.33f67cf3@gandalf.local.home> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Return-path: Content-Disposition: inline In-Reply-To: <20200219103126.33f67cf3@gandalf.local.home> Sender: linux-kernel-owner@vger.kernel.org To: Steven Rostedt Cc: Peter Zijlstra , linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org, mingo@kernel.org, joel@joelfernandes.org, gregkh@linuxfoundation.org, gustavo@embeddedor.com, tglx@linutronix.de, paulmck@kernel.org, josh@joshtriplett.org, mathieu.desnoyers@efficios.com, jiangshanlai@gmail.com, luto@kernel.org, tony.luck@intel.com, frederic@kernel.org, dan.carpenter@oracle.com, mhiramat@kernel.org, Will Deacon , Marc Zyngier , Michael Ellerman , Petr Mladek List-Id: linux-arch.vger.kernel.org On Wed, Feb 19, 2020 at 10:31:26AM -0500, Steven Rostedt wrote: > Probably should document somewhere (in a comment above nmi_enter()?) > that we allow nmi_enter() to nest up to 15 times. Yah, and can we make the BUG_ON() WARN_ON or so instead, so that there's at least a chance to be able to catch it for debugging. Or is the box going to be irreparably wedged after the 4 bits overflow? -- Regards/Gruss, Boris. https://people.kernel.org/tglx/notes-about-netiquette From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.skyhub.de ([5.9.137.197]:55246 "EHLO mail.skyhub.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726528AbgBSQ5D (ORCPT ); Wed, 19 Feb 2020 11:57:03 -0500 Date: Wed, 19 Feb 2020 17:56:50 +0100 From: Borislav Petkov Subject: Re: [PATCH v3 01/22] hardirq/nmi: Allow nested nmi_enter() Message-ID: <20200219165650.GB32346@zn.tnic> References: <20200219144724.800607165@infradead.org> <20200219150744.428764577@infradead.org> <20200219103126.33f67cf3@gandalf.local.home> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20200219103126.33f67cf3@gandalf.local.home> Sender: linux-arch-owner@vger.kernel.org List-ID: To: Steven Rostedt Cc: Peter Zijlstra , linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org, mingo@kernel.org, joel@joelfernandes.org, gregkh@linuxfoundation.org, gustavo@embeddedor.com, tglx@linutronix.de, paulmck@kernel.org, josh@joshtriplett.org, mathieu.desnoyers@efficios.com, jiangshanlai@gmail.com, luto@kernel.org, tony.luck@intel.com, frederic@kernel.org, dan.carpenter@oracle.com, mhiramat@kernel.org, Will Deacon , Marc Zyngier , Michael Ellerman , Petr Mladek Message-ID: <20200219165650.hxC6lHu6hUBrprnrWiSZalAoH04-U1HQY2SrZw4UA6I@z> On Wed, Feb 19, 2020 at 10:31:26AM -0500, Steven Rostedt wrote: > Probably should document somewhere (in a comment above nmi_enter()?) > that we allow nmi_enter() to nest up to 15 times. Yah, and can we make the BUG_ON() WARN_ON or so instead, so that there's at least a chance to be able to catch it for debugging. Or is the box going to be irreparably wedged after the 4 bits overflow? -- Regards/Gruss, Boris. https://people.kernel.org/tglx/notes-about-netiquette