RE: regarding PR http://gnats.netbsd.org/46885

["Haloi, Alakesh" <Alakesh.Haloi%amd.com@localhost>]

Hi Matthew

I had increased the number of 2MB pages to 128. So ideally, it should be able 
to fit upto 256MB of kernel image. But looks like we can go only upto around 
112MB or so [ kernel + embedded ramdisk ]. What could be the issue here? Is 
there a limit on the amount of memory we can reserve for loading the kernel 
image?

Since we tend to load all install stuff, library etc in ramdisk, soon we might 
be needing more than 250MB to hold everything. 

Thanks
Alakesh
________________________________________
From: Haloi, Alakesh
Sent: Friday, January 24, 2014 10:30 AM
To: matthew green
Cc: gnats-bugs%NetBSD.org@localhost; netbsd-bugs%netbsd.org@localhost; 
kern-bug-people%netbsd.org@localhost; lars%heidieker.de@localhost
Subject: RE: regarding PR http://gnats.netbsd.org/46885

Hi Matthew

Thanks. That worked like a charm.

-Alakesh
________________________________________
From: matthew green [mrg%eterna.com.au@localhost]
Sent: Thursday, January 23, 2014 7:26 PM
To: Haloi, Alakesh
Cc: gnats-bugs%NetBSD.org@localhost; netbsd-bugs%netbsd.org@localhost; 
kern-bug-people%netbsd.org@localhost; lars%heidieker.de@localhost
Subject: re: regarding PR http://gnats.netbsd.org/46885

> Hi Lars
>
> This is regarding netbsd bug 46885. We have been seeing same problem on an
> x86 board when we try to boot a netbsd kernel with ramfdisk embedded.  The
> size of ramdisk is 18mb and with kernel, the final kernel is around 31MB.
> When we try to boot this kernel, the system resets mostly before vga or
> serial console is initialized. If the ramdisk is created to be 16mb, then it
> boots fine.
>
> I have experimented with the size of the ramdisk. When i put it at 17mb and
> with few printfs added to the kernel I could see that it went farther in
> the boot process and got uvm page fault while trying to initialize sysctls.
> Please find the attached images that has a a panic stack trace.
>
> Looking at 46885, it seems to be same issue. However we are using netbsd 6.1
> and this issue was fixed for 6.1 but we still see it in our board. We have
> also seen the same issue, on an HP machine ( x86 64bit amd),  There, we
> saw this when trying to install netbsd 6.1 on that machine from official ISO

try increasing this value:

sys/arch/amd64/include/pmap.h:#define NKL2_KIMG_ENTRIES 16

the amd64 kernel must fit in NKL2_KIMG_ENTRIES * 2MB pages.


.mrg.