* [PATCH] s390-bios: Skip writing iplb location to low core for ccw ipl
@ 2020-10-30 12:28 Christian Borntraeger
2020-11-03 12:08 ` Christian Borntraeger
` (2 more replies)
0 siblings, 3 replies; 6+ messages in thread
From: Christian Borntraeger @ 2020-10-30 12:28 UTC (permalink / raw)
To: Thomas Huth
Cc: Jason J. Herne, Janosch Frank, Cornelia Huck, qemu-devel,
Christian Borntraeger, qemu-s390x
From: "Jason J. Herne" <jjherne@linux.ibm.com>
The architecture states that the iplb location is only written to low
core for list directed ipl and not for traditional ccw ipl. If we don't
skip this then operating systems that load by reading into low core
memory may fail to start.
We should also not write the iplb pointer for network boot as it might
overwrite content that we got via network.
Signed-off-by: Jason J. Herne <jjherne@linux.ibm.com>
Fixes: 9bfc04f9ef68 ("pc-bios: s390x: Save iplb location in lowcore")
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
---
pc-bios/s390-ccw/main.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/pc-bios/s390-ccw/main.c b/pc-bios/s390-ccw/main.c
index 43c792cf9509..fc4bfaa45529 100644
--- a/pc-bios/s390-ccw/main.c
+++ b/pc-bios/s390-ccw/main.c
@@ -43,7 +43,9 @@ void write_subsystem_identification(void)
void write_iplb_location(void)
{
- lowcore->ptr_iplb = ptr2u32(&iplb);
+ if (cutype == CU_TYPE_VIRTIO && virtio_get_device_type() != VIRTIO_ID_NET) {
+ lowcore->ptr_iplb = ptr2u32(&iplb);
+ }
}
unsigned int get_loadparm_index(void)
--
2.26.2
^ permalink raw reply related [flat|nested] 6+ messages in thread* Re: [PATCH] s390-bios: Skip writing iplb location to low core for ccw ipl
2020-10-30 12:28 [PATCH] s390-bios: Skip writing iplb location to low core for ccw ipl Christian Borntraeger
@ 2020-11-03 12:08 ` Christian Borntraeger
2020-11-03 12:32 ` Thomas Huth
2020-11-04 12:22 ` Cornelia Huck
2 siblings, 0 replies; 6+ messages in thread
From: Christian Borntraeger @ 2020-11-03 12:08 UTC (permalink / raw)
To: Thomas Huth
Cc: Jason J. Herne, qemu-s390x, Cornelia Huck, Janosch Frank,
qemu-devel
On 30.10.20 13:28, Christian Borntraeger wrote:
> From: "Jason J. Herne" <jjherne@linux.ibm.com>
>
> The architecture states that the iplb location is only written to low
> core for list directed ipl and not for traditional ccw ipl. If we don't
> skip this then operating systems that load by reading into low core
> memory may fail to start.
>
> We should also not write the iplb pointer for network boot as it might
> overwrite content that we got via network.
>
> Signed-off-by: Jason J. Herne <jjherne@linux.ibm.com>
> Fixes: 9bfc04f9ef68 ("pc-bios: s390x: Save iplb location in lowcore")
> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
FWIW, this fixes the vfio-ccw IPL for some non Linux binaries.
> ---
> pc-bios/s390-ccw/main.c | 4 +++-
> 1 file changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/pc-bios/s390-ccw/main.c b/pc-bios/s390-ccw/main.c
> index 43c792cf9509..fc4bfaa45529 100644
> --- a/pc-bios/s390-ccw/main.c
> +++ b/pc-bios/s390-ccw/main.c
> @@ -43,7 +43,9 @@ void write_subsystem_identification(void)
>
> void write_iplb_location(void)
> {
> - lowcore->ptr_iplb = ptr2u32(&iplb);
> + if (cutype == CU_TYPE_VIRTIO && virtio_get_device_type() != VIRTIO_ID_NET) {
> + lowcore->ptr_iplb = ptr2u32(&iplb);
> + }
> }
>
> unsigned int get_loadparm_index(void)
>
^ permalink raw reply [flat|nested] 6+ messages in thread* Re: [PATCH] s390-bios: Skip writing iplb location to low core for ccw ipl
2020-10-30 12:28 [PATCH] s390-bios: Skip writing iplb location to low core for ccw ipl Christian Borntraeger
2020-11-03 12:08 ` Christian Borntraeger
@ 2020-11-03 12:32 ` Thomas Huth
2020-11-03 12:35 ` Cornelia Huck
2020-11-03 17:15 ` Christian Borntraeger
2020-11-04 12:22 ` Cornelia Huck
2 siblings, 2 replies; 6+ messages in thread
From: Thomas Huth @ 2020-11-03 12:32 UTC (permalink / raw)
To: Christian Borntraeger
Cc: Jason J. Herne, qemu-s390x, Cornelia Huck, qemu-devel,
Janosch Frank
On 30/10/2020 13.28, Christian Borntraeger wrote:
> From: "Jason J. Herne" <jjherne@linux.ibm.com>
>
> The architecture states that the iplb location is only written to low
> core for list directed ipl and not for traditional ccw ipl. If we don't
> skip this then operating systems that load by reading into low core
> memory may fail to start.
Just double-checking: But doing write_subsystem_identification()
unconditionally is ok, right?
> We should also not write the iplb pointer for network boot as it might
> overwrite content that we got via network.
FWIW, write_iplb_location() is already just a dummy function in netmain.c,
so this should not have been an issue in the network bootloader, I hope.
> Signed-off-by: Jason J. Herne <jjherne@linux.ibm.com>
> Fixes: 9bfc04f9ef68 ("pc-bios: s390x: Save iplb location in lowcore")
> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
> ---
> pc-bios/s390-ccw/main.c | 4 +++-
> 1 file changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/pc-bios/s390-ccw/main.c b/pc-bios/s390-ccw/main.c
> index 43c792cf9509..fc4bfaa45529 100644
> --- a/pc-bios/s390-ccw/main.c
> +++ b/pc-bios/s390-ccw/main.c
> @@ -43,7 +43,9 @@ void write_subsystem_identification(void)
>
> void write_iplb_location(void)
> {
> - lowcore->ptr_iplb = ptr2u32(&iplb);
> + if (cutype == CU_TYPE_VIRTIO && virtio_get_device_type() != VIRTIO_ID_NET) {
> + lowcore->ptr_iplb = ptr2u32(&iplb);
> + }
> }
Acked-by: Thomas Huth <thuth@redhat.com>
Christian, Cornelia, could you please pick up the patch? I'm not sure
whether I can do another PR this week for the RC...
^ permalink raw reply [flat|nested] 6+ messages in thread* Re: [PATCH] s390-bios: Skip writing iplb location to low core for ccw ipl
2020-11-03 12:32 ` Thomas Huth
@ 2020-11-03 12:35 ` Cornelia Huck
2020-11-03 17:15 ` Christian Borntraeger
1 sibling, 0 replies; 6+ messages in thread
From: Cornelia Huck @ 2020-11-03 12:35 UTC (permalink / raw)
To: Thomas Huth
Cc: Jason J. Herne, Christian Borntraeger, qemu-s390x, qemu-devel,
Janosch Frank
On Tue, 3 Nov 2020 13:32:47 +0100
Thomas Huth <thuth@redhat.com> wrote:
> On 30/10/2020 13.28, Christian Borntraeger wrote:
> > From: "Jason J. Herne" <jjherne@linux.ibm.com>
> >
> > The architecture states that the iplb location is only written to low
> > core for list directed ipl and not for traditional ccw ipl. If we don't
> > skip this then operating systems that load by reading into low core
> > memory may fail to start.
>
> Just double-checking: But doing write_subsystem_identification()
> unconditionally is ok, right?
>
> > We should also not write the iplb pointer for network boot as it might
> > overwrite content that we got via network.
>
> FWIW, write_iplb_location() is already just a dummy function in netmain.c,
> so this should not have been an issue in the network bootloader, I hope.
>
> > Signed-off-by: Jason J. Herne <jjherne@linux.ibm.com>
> > Fixes: 9bfc04f9ef68 ("pc-bios: s390x: Save iplb location in lowcore")
> > Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
> > ---
> > pc-bios/s390-ccw/main.c | 4 +++-
> > 1 file changed, 3 insertions(+), 1 deletion(-)
> >
> > diff --git a/pc-bios/s390-ccw/main.c b/pc-bios/s390-ccw/main.c
> > index 43c792cf9509..fc4bfaa45529 100644
> > --- a/pc-bios/s390-ccw/main.c
> > +++ b/pc-bios/s390-ccw/main.c
> > @@ -43,7 +43,9 @@ void write_subsystem_identification(void)
> >
> > void write_iplb_location(void)
> > {
> > - lowcore->ptr_iplb = ptr2u32(&iplb);
> > + if (cutype == CU_TYPE_VIRTIO && virtio_get_device_type() != VIRTIO_ID_NET) {
> > + lowcore->ptr_iplb = ptr2u32(&iplb);
> > + }
> > }
>
> Acked-by: Thomas Huth <thuth@redhat.com>
>
> Christian, Cornelia, could you please pick up the patch? I'm not sure
> whether I can do another PR this week for the RC...
Will do, I have other things as well anyway.
^ permalink raw reply [flat|nested] 6+ messages in thread* Re: [PATCH] s390-bios: Skip writing iplb location to low core for ccw ipl
2020-11-03 12:32 ` Thomas Huth
2020-11-03 12:35 ` Cornelia Huck
@ 2020-11-03 17:15 ` Christian Borntraeger
1 sibling, 0 replies; 6+ messages in thread
From: Christian Borntraeger @ 2020-11-03 17:15 UTC (permalink / raw)
To: Thomas Huth
Cc: Jason J. Herne, qemu-s390x, Cornelia Huck, qemu-devel,
Janosch Frank
On 03.11.20 13:32, Thomas Huth wrote:
> On 30/10/2020 13.28, Christian Borntraeger wrote:
>> From: "Jason J. Herne" <jjherne@linux.ibm.com>
>>
>> The architecture states that the iplb location is only written to low
>> core for list directed ipl and not for traditional ccw ipl. If we don't
>> skip this then operating systems that load by reading into low core
>> memory may fail to start.
>
> Just double-checking: But doing write_subsystem_identification()
> unconditionally is ok, right?
Yes, for any channel device IPL the subsystem ID is stored in absolute locations
184-187 so this should be good as virtio is a channel device.
>
>> We should also not write the iplb pointer for network boot as it might
>> overwrite content that we got via network.
>
> FWIW, write_iplb_location() is already just a dummy function in netmain.c,
> so this should not have been an issue in the network bootloader, I hope.
OK. I think we can keep the check for !VIRTIO_ID_NET anyway.
>
>> Signed-off-by: Jason J. Herne <jjherne@linux.ibm.com>
>> Fixes: 9bfc04f9ef68 ("pc-bios: s390x: Save iplb location in lowcore")
>> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
>> ---
>> pc-bios/s390-ccw/main.c | 4 +++-
>> 1 file changed, 3 insertions(+), 1 deletion(-)
>>
>> diff --git a/pc-bios/s390-ccw/main.c b/pc-bios/s390-ccw/main.c
>> index 43c792cf9509..fc4bfaa45529 100644
>> --- a/pc-bios/s390-ccw/main.c
>> +++ b/pc-bios/s390-ccw/main.c
>> @@ -43,7 +43,9 @@ void write_subsystem_identification(void)
>>
>> void write_iplb_location(void)
>> {
>> - lowcore->ptr_iplb = ptr2u32(&iplb);
>> + if (cutype == CU_TYPE_VIRTIO && virtio_get_device_type() != VIRTIO_ID_NET) {
>> + lowcore->ptr_iplb = ptr2u32(&iplb);
>> + }
>> }
>
> Acked-by: Thomas Huth <thuth@redhat.com>
>
> Christian, Cornelia, could you please pick up the patch? I'm not sure
> whether I can do another PR this week for the RC...
>
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH] s390-bios: Skip writing iplb location to low core for ccw ipl
2020-10-30 12:28 [PATCH] s390-bios: Skip writing iplb location to low core for ccw ipl Christian Borntraeger
2020-11-03 12:08 ` Christian Borntraeger
2020-11-03 12:32 ` Thomas Huth
@ 2020-11-04 12:22 ` Cornelia Huck
2 siblings, 0 replies; 6+ messages in thread
From: Cornelia Huck @ 2020-11-04 12:22 UTC (permalink / raw)
To: Christian Borntraeger
Cc: qemu-s390x, Jason J. Herne, Thomas Huth, qemu-devel,
Janosch Frank
On Fri, 30 Oct 2020 13:28:23 +0100
Christian Borntraeger <borntraeger@de.ibm.com> wrote:
> From: "Jason J. Herne" <jjherne@linux.ibm.com>
>
> The architecture states that the iplb location is only written to low
> core for list directed ipl and not for traditional ccw ipl. If we don't
> skip this then operating systems that load by reading into low core
> memory may fail to start.
>
> We should also not write the iplb pointer for network boot as it might
> overwrite content that we got via network.
>
> Signed-off-by: Jason J. Herne <jjherne@linux.ibm.com>
> Fixes: 9bfc04f9ef68 ("pc-bios: s390x: Save iplb location in lowcore")
> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
> ---
> pc-bios/s390-ccw/main.c | 4 +++-
> 1 file changed, 3 insertions(+), 1 deletion(-)
Thanks, queued (together with a rebuild) to s390-fixes.
^ permalink raw reply [flat|nested] 6+ messages in thread
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2020-10-30 12:28 [PATCH] s390-bios: Skip writing iplb location to low core for ccw ipl Christian Borntraeger
2020-11-03 12:08 ` Christian Borntraeger
2020-11-03 12:32 ` Thomas Huth
2020-11-03 12:35 ` Cornelia Huck
2020-11-03 17:15 ` Christian Borntraeger
2020-11-04 12:22 ` Cornelia Huck
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