Re: [PULL v2 4/6] spapr: Add /chosen to FDT only at reset time to preserve kernel and initramdisk

[Laurent Vivier]

Bad reply, the problem is with

"spapr: Render full FDT on ibm,client-architecture-support"

Sorry,
Laurent

On 03/12/2019 16:57, Laurent Vivier wrote:
> On 18/11/2019 11:53, Laurent Vivier wrote:
>> From: Alexey Kardashevskiy <address@hidden>
>>
>> Since "spapr: Render full FDT on ibm,client-architecture-support" we build
>> the entire flatten device tree (FDT) twice - at the reset time and
>> when "ibm,client-architecture-support" (CAS) is called. The full FDT from
>> CAS is then applied on top of the SLOF internal device tree.
>>
>> This is mostly ok, however there is a case when the QEMU is started with
>> -initrd and for some reason the guest decided to move/unpack the init RAM
>> disk image - the guest correctly notifies SLOF about the change but
>> at CAS it is overridden with the QEMU initial location addresses and
>> the guest may fail to boot if the original initrd memory was changed.
>>
>> This fixes the problem by only adding the /chosen node at the reset time
>> to prevent the original QEMU's linux,initrd-start/linux,initrd-end to
>> override the updated addresses.
>>
>> This only treats /chosen differently as we know there is a special case
>> already and it is unlikely anything else will need to change /chosen at CAS
>> we are better off not touching /chosen after we handed it over to SLOF.
>>
>> Signed-off-by: Alexey Kardashevskiy <address@hidden>
>> Message-Id: <address@hidden>
>> Signed-off-by: David Gibson <address@hidden>
>> Signed-off-by: Laurent Vivier <address@hidden>
>> ---
>>  hw/ppc/spapr.c | 25 +++++++++++++++----------
>>  1 file changed, 15 insertions(+), 10 deletions(-)
>>
> 
> This patch breaks pseries boot when we use a pci-bridge (since v4.2.0-rc0):
> 
> ...
>     -device pci-bridge,id=pci_bridge1,bus=pci.0,addr=0x3,chassis_nr=1 \
>     -device virtio-scsi-pci,bus=pci_bridge1 \
> ...
> 
> OF stdout device is: /vdevice/vty@71000000
> Preparing to boot Linux version 5.4.0-rc3+ (lvivier@localhost) (gcc
> version 4.8.5 20150623 (Red Hat 4.8.5-39) (GCC)) #2 SMP Wed Nov 13
> 09:08:20 EST 2019
> Detected machine type: 0000000000000101
> command line: BOOT_IMAGE=/vmlinuz-5.4.0-rc3+ root=/dev/mapper/rhel-root
> ro crashkernel=auto rd.lvm.lv=rhel/root rd.lvm.lv=rhel/swap
> Max number of cores passed to firmware: 2048 (NR_CPUS = 2048)
> Calling ibm,client-architecture-support...
> 
> ( 300 ) Data Storage Exception [ 1dc5f230 ]
> 
> 
>     R0 .. R7           R8 .. R15         R16 .. R23         R24 .. R31
> 8000000000001000   000000001e477010   0000000000000000   000000001dc17500
> 000000001e67afe0   0000000020000004   0000000000000000   000000001dc1bf88
> 000000001dc21800   000000001dc5f248   000000001e477010   0000000000000003
> 000000001dc61000   000000001e78dc2d   000000001dc1c158   000000000000f001
> 0000000000000000   a000000000000001   0000000000008000   000000001e67b060
> 000000001dc5f230   0000000000000000   000000000000f003   ffffffffffffffff
> 000000001e745860   0000000000000000   0000000000000006   000000001dbf48f8
> 000000001dc5f248   0000000000000000   000000001e67b050   000000001dc1c350
> 
>     CR / XER           LR / CTR          SRR0 / SRR1        DAR / DSISR
>         80000808   000000001dbf34d4   000000001dbf4194   0000000020000004
> 0000000020000000   000000001dbf48f8   8000000000001000           40000000
> 
> 
> 4a >
> 
> Thanks,
> Laurent
>