Re: [Bug 204789] New: Boot failure with more than 256G of memory

From: Cameron Berkenpas <cam@neo-zeon.de>
To: Andrew Morton <akpm@linux-foundation.org>
Cc: bugzilla-daemon@bugzilla.kernel.org, linuxppc-dev@lists.ozlabs.org
Subject: Re: [Bug 204789] New: Boot failure with more than 256G of memory
Date: Wed, 11 Sep 2019 08:34:48 -0700	[thread overview]
Message-ID: <b966080e-0a5f-a584-9fe3-85d26be8fda4@neo-zeon.de> (raw)
In-Reply-To: <20190911073153.9df4d4618d7f99752cd18edd@linux-foundation.org>

Hello,

Regression set to "yes". Not sure how I missed that. :)

Will report future PPC issues to that I come across to this list as well.

Thanks!

-Cameron

On 9/11/19 7:31 AM, Andrew Morton wrote:
> (switched to email.  Please respond via emailed reply-to-all, not via the
> bugzilla web interface).
>
> On Sun, 08 Sep 2019 00:04:26 +0000 bugzilla-daemon@bugzilla.kernel.org wrote:
>
>> https://bugzilla.kernel.org/show_bug.cgi?id=204789
>>
>>              Bug ID: 204789
>>             Summary: Boot failure with more than 256G of memory
>>             Product: Memory Management
>>             Version: 2.5
>>      Kernel Version: 5.2.x
>>            Hardware: PPC-64
>>                  OS: Linux
>>                Tree: Mainline
>>              Status: NEW
>>            Severity: high
>>            Priority: P1
>>           Component: Other
>>            Assignee: akpm@linux-foundation.org
>>            Reporter: cam@neo-zeon.de
>>          Regression: No
> "Yes" :)
>
>> Kernel series 5.2.x will not boot on my Talos II workstation with dual POWER9
>> 18 core processors and 512G of physical memory with disable_radix=yes and 4k
>> pages.
>>
>> 5.3-rc6 did not work either.
>>
>> 5.1 and earlier boot fine.
> Thanks.  It's probably best to report this on the powerpc list, cc'ed here.
>
>> I can get the system to boot IF I leave the Radix MMU enabled or if I boot a
>> kernel with 64k pages. I haven't yet tested enabling the Radix MMU with 64k
>> pages at the same time, but I suspect this would work. This is a system I
>> cannot take down TOO frequently.
>>
>> The system will also boot with the Radix MMU disabled and 4k pages with 256G or
>> less memory. Setting mem on the kernel CLI to 256G or less results in a
>> successful boot. Setting mem=257G or higher no Radix MMU and 4k pages and the
>> kernel will not boot.
>>
>> Petitboot comes up, but the system fails VERY early in boot in the serial
>> console with:
>> SIGTERM received, booting...
>> [   23.838858] kexec_core: Starting new kernel
>>
>> Early printk is enabled, and it never progresses any further.
>>
>> 5.1 boots just fine with the Radix MMU disabled and 4k pages.
>>
>> Unfortunately, I currently need 4k pages for bcache to work, and Radix MMU
>> disabled in order for FreeBSD 12.x to work under KVM so I'm sticking with
>> 5.1.21 for now.
>>
>> I have been unable to reproduce this issue in KVM.
>>
>> Here are my PCIe peripherals:
>> 1. Microsemi/Adaptec HBA 1100-4i SAS controller
>> 2. Megaraid 9316-16i SAS RAID controller.
>>
>> I've only tried little endian as this is a little endian install.
>>
>> -- 
>> You are receiving this mail because:
>> You are the assignee for the bug.