With upcoming patches, normal guests might touch secure pages.
This patch extends the existing exception handler to convert the pages
to non secure also when the exception is triggered by a normal guest.
Signed-off-by: Claudio Imbrenda <imbrenda@xxxxxxxxxxxxx>
---
arch/s390/mm/fault.c | 12 +++++++++++-
1 file changed, 11 insertions(+), 1 deletion(-)
diff --git a/arch/s390/mm/fault.c b/arch/s390/mm/fault.c
index efdef35bc415..24a39457cd48 100644
--- a/arch/s390/mm/fault.c
+++ b/arch/s390/mm/fault.c
@@ -789,9 +789,20 @@ void do_secure_storage_access(struct pt_regs *regs)
struct vm_area_struct *vma;
struct mm_struct *mm;
struct page *page;
+ struct gmap *gmap;
int rc;
switch (get_fault_type(regs)) {
+ case GMAP_FAULT:
+ gmap = (struct gmap *)S390_lowcore.gmap;
+ /*
+ * Very unlikely, but if it happens, simply try again.
+ * The next attempt will trigger a different exception.
+ */
+ addr = __gmap_translate(gmap, addr);
+ if (addr == -EFAULT)
+ break;
+ fallthrough;
case USER_FAULT:
mm = current->mm;
mmap_read_lock(mm);
@@ -820,7 +831,6 @@ void do_secure_storage_access(struct pt_regs *regs)
if (rc)
BUG();
break;
- case GMAP_FAULT:
default:
do_fault_error(regs, VM_READ | VM_WRITE, VM_FAULT_BADMAP);
WARN_ON_ONCE(1);
--
2.31.1
