The command is used to decrypt a page of guest memory for debug.
The command will be used by qemu monitor dump and gdbserver to access
the guest memory for debug purposes. A typical usage look like:
cpu_physical_memory_rw_debug
cpu_physical_memory_rw_debug_internal
sev_debug_decrypt
Signed-off-by: Brijesh Singh <brijesh.si...@amd.com>
---
sev.c | 28 +++++++++++++++++++++++++---
1 file changed, 25 insertions(+), 3 deletions(-)
diff --git a/sev.c b/sev.c
index ff9266a..f690a86 100644
--- a/sev.c
+++ b/sev.c
@@ -329,6 +329,28 @@ err:
}
static int
+sev_debug_decrypt(SEVState *s, uint8_t *dst, const uint8_t *src, uint32_t len)
+{
+ int ret;
+ struct kvm_sev_dbg_decrypt *dbg;
+
+ dbg = g_malloc0(sizeof(*dbg));
+ if (!dbg) {
+ return 1;
+ }
+
+ dbg->src_addr = (unsigned long)src;
+ dbg->dst_addr = (unsigned long)dst;
+ dbg->length = len;
+
+ ret = sev_ioctl(KVM_SEV_DBG_DECRYPT, dbg);
+ DPRINTF("SEV: DBG_DECRYPT src %#lx dst %#lx len %#x\n",
+ (uint64_t)src, (uint64_t)dst, len);
+ g_free(dbg);
+ return ret;
+}
+
+static int
sev_mem_write(uint8_t *dst, const uint8_t *src, uint32_t len, MemTxAttrs attrs)
{
SEVState *s = kvm_memory_encryption_get_handle();
@@ -348,9 +370,9 @@ sev_mem_read(uint8_t *dst, const uint8_t *src, uint32_t
len, MemTxAttrs attrs)
{
SEVState *s = kvm_memory_encryption_get_handle();
- assert(s != NULL && s->state != SEV_STATE_INVALID);
+ assert(attrs.debug || (s != NULL && s->state != SEV_STATE_INVALID));
- return 0;
+ return sev_debug_decrypt(s, dst, src, len);
}
static int
@@ -453,7 +475,7 @@ sev_guest_mem_dec(void *handle, uint8_t *dst, const uint8_t
*src, uint32_t len)
assert(s != NULL && s->state != SEV_STATE_INVALID);
/* use SEV debug command to decrypt memory */
- return 1;
+ return sev_debug_decrypt((SEVState *)handle, dst, src, len);
}
int
