From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Magnus Damm" Date: Wed, 31 Jan 2007 05:57:54 +0000 Subject: Re: [Fastboot] [PATCH] kexec: Avoid migration of already disabled irqs (ia64) Message-Id: List-Id: References: <45C005C1.5010606@sgi.com> In-Reply-To: <45C005C1.5010606@sgi.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: linux-ia64@vger.kernel.org Hi Nan hai, On 1/31/07, Zou, Nanhai wrote: > > On 1/31/07, Jay Lan wrote: > > > Magnus Damm wrote: > > > > kexec: Avoid migration of already disabled irqs (ia64) > > > > > > > > This patch fixes up ia64 kexec support for HP rx2620 hardware. It does this > > > > by skipping migration of already disabled irqs. This is most likely a problem > > > > on other ia64 platforms as well, but I've only tested this on one machine > > > > so far. > > > > > > I have not seen this problem on SN systems. > > > > Ok, thanks. Let me give you more details. > > > > When I perform "kexec -e" the following output appears on my serial > > console (with my patch applied). > > This patch is correct I think. I assume you will also see this bug when trying to offline a CPU by echo 0 > /sys/devices/system/cpu/cpuX/online You are right, I can trigger the bug that way too. And the bug goes away with the patch. Excellent! > However it will not be triggered in crash dump case which has been tested heavily on different kind of platforms. We do not migrate IRQ at the time of crash. I guess that is why Jay has never seen it on SN platforms. Booting into a crash kernel does not seem to work on this ia64 box unfortunately. I'm about to investigate why, but I thought trying and fixing kexec was a good first step. Thanks for the help! / magnus