KVM: s390: consider system MHA for guest storage

Verify that the guest maximum storage address is below the MHA (maximum
host address) value allowed on the host.

Acked-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Guenther Hutzl <hutzl@linux.vnet.ibm.com>
Signed-off-by: Dominik Dingel <dingel@linux.vnet.ibm.com>
[adopt to match recent limit,size changes]

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>

1 files changed, 7 insertions, 1 deletions

diff --git a/drivers/s390/char/sclp_early.c b/drivers/s390/char/sclp_early.c
index e0a1f4eec370..6804354c42bd 100644
--- a/drivers/s390/char/sclp_early.c
+++ b/drivers/s390/char/sclp_early.c
@@ -40,7 +40,8 @@ struct read_info_sccb {
         u8      fac85;                  /* 85 */
         u8      _pad_86[91 - 86];       /* 86-90 */
         u8      flags;                  /* 91 */
-        u8      _pad_92[100 - 92];      /* 92-99 */
+        u8      _pad_92[99 - 92];       /* 92-98 */
+        u8      hamaxpow;               /* 99 */
         u32     rnsize2;                /* 100-103 */
         u64     rnmax2;                 /* 104-111 */
         u8      _pad_112[116 - 112];    /* 112-115 */
@@ -120,6 +121,11 @@ static void __init sclp_facilities_detect(struct read_info_sccb *sccb)
         sclp.rzm <<= 20;
         sclp.ibc = sccb->ibc;
 
+        if (sccb->hamaxpow && sccb->hamaxpow < 64)
+                sclp.hamax = (1UL << sccb->hamaxpow) - 1;
+        else
+                sclp.hamax = U64_MAX;
+
         if (!sccb->hcpua) {
                 if (MACHINE_IS_VM)
                         sclp.max_cores = 64;