> -----Original Message----- > From: Magnus Damm [mailto:magnus.damm@xxxxxxxxx] > Sent: 2007年1月31日 13:58 > To: Zou, Nanhai > Cc: Jay Lan; Magnus Damm; linux-ia64@xxxxxxxxxxxxxxx; Luck, Tony; > fastboot@xxxxxxxxxxxxxx > Subject: Re: [Fastboot] [PATCH] kexec: Avoid migration of already disabled irqs > (ia64) > > Hi Nan hai, > > On 1/31/07, Zou, Nanhai <nanhai.zou@xxxxxxxxx> wrote: > > > On 1/31/07, Jay Lan <jlan@xxxxxxx> 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. > That is probably caused by HP's IOMMU engine not shutting down at crash time...., Please try add machvec=dig option for the crash dump kernel. However we still need to find a light way to correctly shutdown IOMMU engine on those HP platforms. Thanks Zou Nan hai > Thanks for the help! > > / magnus - To unsubscribe from this list: send the line "unsubscribe linux-ia64" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
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