2016-07-21 18:19 GMT+03:00 Daniel Walker <danielwa at cisco.com>: > > There appears to be no code which checks what is or is not System ram, > there is nothing that checks the device tree to see what is IO memory, and > nothing reads /proc/iomem .. So AFAIK nothing cares if it's IO memory, or > system ram, and there's no method to config things to skip any memory in the > system, except in makedumpfile which can skip symbols not IO memory. > > Daniel, unfortunately it's long time for me when I looked to powerpc code. But I just checked that here: kexec-tools-2.0.6/kexec/arch/ppc64/kexec-ppc64.c is probably what you need. Maxim. > > On 07/21/2016 12:34 AM, Maxim Uvarov wrote: >> >> Second kernel should already know that it's not system ram of the >> first kernel and in that case makedumpfile will not dump that memory. >> Simple way is to pass additional kernel argument to kexec is when you >> load the kernel. If it works than you can think how it's better to >> pass this parameter. Variants might be request_resource() in first >> kernel or add some logic to kexec tools. >> >> Best regards, >> Maxim. >> >> 2016-07-20 22:18 GMT+03:00 Daniel Walker <danielwa at cisco.com>: >>> >>> Mahesh, I didn't get your email for some reason . I saw it in the >>> Archives. >>> >>> makedumpfile doesn't appear to have a way to drop free form memory areas. >>> So >>> I need to drop 00800000 to 00807fff , but I don't see a way to do that. >>> Any >>> other suggestions on how to prevent this hang ? >>> >>> >>> >>> On 07/11/2016 02:46 PM, Daniel Walker wrote: >>>> >>>> >>>> Hi, >>>> >>>> I found found that on my Powerpc machine there is some IO memory which >>>> will cause the box to hang if I read it. It's a custom device that was >>>> added >>>> to the board for a special purpose. >>>> >>>> I was looking for a way to exclude this memory from the dump, and while >>>> doing that I found that kexec makes a list of memory segments that go >>>> into >>>> the core file. I was wondering why most of the kexec architecture don't >>>> appear to exclude device memory like what's listed in /proc/iomem. >>>> >>>> Is there a good reason why that's not the case? >>>> >>>> Daniel >>> >>> >>> >>> _______________________________________________ >>> kexec mailing list >>> kexec at lists.infradead.org >>> http://lists.infradead.org/mailman/listinfo/kexec >> >> >> > -- Best regards, Maxim Uvarov
