On 8/17/20 12:30 PM, Cornelia Huck wrote:
On Mon, 17 Aug 2020 10:17:34 -0400
"Jason J. Herne" <[email protected]> wrote:
The POP states that the IPLB location is only written to 0x14 for
list-directed IPL. Some operating systems expect 0x14 to not change on
boot and will fail IPL if it does change.
Fixes: 9bfc04f9ef6802fff0
Should be
Fixes: 9bfc04f9ef68 ("pc-bios: s390x: Save iplb location in lowcore")
Signed-off-by: Jason J. Herne <[email protected]>
Reviewed-by: Janosch Frank <[email protected]>
---
pc-bios/s390-ccw/jump2ipl.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/pc-bios/s390-ccw/jump2ipl.c b/pc-bios/s390-ccw/jump2ipl.c
index 767012bf0c..5e3e13f4b0 100644
--- a/pc-bios/s390-ccw/jump2ipl.c
+++ b/pc-bios/s390-ccw/jump2ipl.c
@@ -33,7 +33,10 @@ void jump_to_IPL_code(uint64_t address)
{
/* store the subsystem information _after_ the bootmap was loaded */
write_subsystem_identification();
- write_iplb_location();
+
+ if (iplb.pbt != S390_IPL_TYPE_CCW) {
+ write_iplb_location();
+ }
What happens for ipl types other than CCW and FCP? IOW, should that
rather be a positive check for S390_IPL_TYPE_FCP?
/* prevent unknown IPL types in the guest */
if (iplb.pbt == S390_IPL_TYPE_QEMU_SCSI) {
Based on my (admittedly limited) understanding of the architecture and
code, I believe write_iplb_location() should be called at least for
S390_IPL_TYPE_FCP but I'm not 100% sure on S390_IPL_TYPE_QEMU_SCSI.
Perhaps Janosch has an idea?
It was originally unconditional, and my new conditional excludes vfio
CCW which is definitely a step in the right direction, in any case :).
--
-- Jason J. Herne ([email protected])
