[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [Qemu-devel] [RFC 0/3] Draft implementation of HPT resizing (qemu si
From: |
Bharata B Rao |
Subject: |
Re: [Qemu-devel] [RFC 0/3] Draft implementation of HPT resizing (qemu side) |
Date: |
Tue, 19 Jan 2016 13:18:17 +0530 |
User-agent: |
Mutt/1.5.23 (2014-03-12) |
On Mon, Jan 18, 2016 at 04:44:38PM +1100, David Gibson wrote:
> Here is a draft qemu implementation of my proposed PAPR extension for
> allowing runtime resizing of a KVM/ppc64 guest's hash page table.
> That in turn will allow for more flexible memory hotplug.
>
> This should work with the guest kernel side patches I also posted
> recently [1].
>
> Still required to make this into a full implementation:
> * Guest needs to auto-resize HPT on memory hotplug events
>
> * qemu needs to allocate HPT size based on current rather than
> maximum memory if the guest is HPT resize aware
>
> * KVM host side implementation
>
> * PAPR standardization
So with the current patchset (QEMU and guest kernel changes), I should
be able to change the HTAB size of a PR guest right ? I see the below
failure though:
address@hidden ~]# cat /sys/kernel/debug/powerpc/pft-size
24
address@hidden ~]# echo 26 > /sys/kernel/debug/powerpc/pft-size
[ 65.996845] lpar: Attempting to resize HPT to shift 26
[ 65.996845] lpar: Attempting to resize HPT to shift 26
[ 66.113596] lpar: HPT resize to shift 26 complete (109 ms / 6 ms)
[ 66.113596] lpar: HPT resize to shift 26 complete (109 ms / 6 ms)
PR guest just hangs here while I see tons of below messages in
the 1st level guest:
KVM can't copy data from 0x3fff99e91400!
...
Couldn't emulate instruction 0x00000000 (op 0 xop 0)
kvmppc_handle_exit_pr: emulation at 700 failed (00000000)
Regards,
Bharata.
- [Qemu-devel] [RFC 0/3] Draft implementation of HPT resizing (qemu side), David Gibson, 2016/01/18
- [Qemu-devel] [RFC 2/3] pseries: Implement HPT resizing, David Gibson, 2016/01/18
- [Qemu-devel] [RFC 3/3] pseries: Advertise HPT resize capability, David Gibson, 2016/01/18
- [Qemu-devel] [RFC 1/3] pseries: Stub hypercalls for HPT resizing, David Gibson, 2016/01/18
- Re: [Qemu-devel] [RFC 0/3] Draft implementation of HPT resizing (qemu side), David Gibson, 2016/01/18
- Re: [Qemu-devel] [RFC 0/3] Draft implementation of HPT resizing (qemu side),
Bharata B Rao <=
- Re: [Qemu-devel] [RFC 0/3] Draft implementation of HPT resizing (qemu side), David Gibson, 2016/01/19
- Re: [Qemu-devel] [RFC 0/3] Draft implementation of HPT resizing (qemu side), Alexander Graf, 2016/01/28
- Re: [Qemu-devel] [RFC 0/3] Draft implementation of HPT resizing (qemu side), Paul Mackerras, 2016/01/28
- Re: [Qemu-devel] [RFC 0/3] Draft implementation of HPT resizing (qemu side), David Gibson, 2016/01/28
- Re: [Qemu-devel] [RFC 0/3] Draft implementation of HPT resizing (qemu side), Alexander Graf, 2016/01/29
- Re: [Qemu-devel] [RFC 0/3] Draft implementation of HPT resizing (qemu side), David Gibson, 2016/01/30