s390x/kvm: legacy_s390_alloc() only supports one allocation

We always allocate at a fixed address, a second allocation can therefore
of course never work. We would simply overwrite mappings.

This can e.g. happen in s390_memory_init(), if trying to allocate more
than > 8TB. Let's just bail out, as there is no need for supporting it
(legacy handling for z/VM).

Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20180628113817.30814-2-david@redhat.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
master
David Hildenbrand 2018-06-28 13:38:16 +02:00 committed by Cornelia Huck
parent d66b43c896
commit 8151942151
1 changed files with 10 additions and 2 deletions

View File

@ -752,12 +752,20 @@ int kvm_s390_mem_op(S390CPU *cpu, vaddr addr, uint8_t ar, void *hostbuf,
*/
static void *legacy_s390_alloc(size_t size, uint64_t *align, bool shared)
{
void *mem;
static void *mem;
if (mem) {
/* we only support one allocation, which is enough for initial ram */
return NULL;
}
mem = mmap((void *) 0x800000000ULL, size,
PROT_EXEC|PROT_READ|PROT_WRITE,
MAP_SHARED | MAP_ANONYMOUS | MAP_FIXED, -1, 0);
return mem == MAP_FAILED ? NULL : mem;
if (mem == MAP_FAILED) {
mem = NULL;
}
return mem;
}
static uint8_t const *sw_bp_inst;