[PATCH 09/11] hw/i386: set ram_debug_ops when memory encryption is enabled

Ashish Kalra
2020-11-16T18:53:02Z

From: Brijesh Singh <brijesh.singh@amd.com>

When memory encryption is enabled, the guest RAM and boot flash ROM will
contain the encrypted data. By setting the debug ops allow us to invoke
encryption APIs when accessing the memory for the debug purposes.

Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
Signed-off-by: Ashish Kalra <ashish.kalra@amd.com>
---
hw/i386/pc.c | 9 +++++++++
hw/i386/pc_sysfw.c | 6 ++++++
2 files changed, 15 insertions(+)

diff --git a/hw/i386/pc.c b/hw/i386/pc.c
index 5e6c0023e0..dfb63cd686 100644
--- a/hw/i386/pc.c
+++ b/hw/i386/pc.c
@@ -913,6 +913,15 @@ void pc_memory_init(PCMachineState *pcms,
e820_add_entry(0x100000000ULL, x86ms->above_4g_mem_size, E820_RAM);
}

+ /*
+ * When memory encryption is enabled, the guest RAM will be encrypted with
+ * a guest unique key. Set the debug ops so that any debug access to the
+ * guest RAM will go through the memory encryption APIs.
+ */
+ if (kvm_memcrypt_enabled()) {
+ kvm_memcrypt_set_debug_ops_memory_region(*ram_memory);
+ }
+
if (!pcmc->has_reserved_memory &&
(machine->ram_slots ||
(machine->maxram_size > machine->ram_size))) {
diff --git a/hw/i386/pc_sysfw.c b/hw/i386/pc_sysfw.c
index b6c0822fe3..9f90c9d761 100644
--- a/hw/i386/pc_sysfw.c
+++ b/hw/i386/pc_sysfw.c
@@ -209,6 +209,12 @@ static void pc_system_flash_map(PCMachineState *pcms,
error_report("failed to encrypt pflash rom");
exit(1);
}
+
+ /*
+ * The pflash ROM is encrypted, set the debug ops so that any
+ * debug accesses will use memory encryption APIs.
+ */
+ kvm_memcrypt_set_debug_ops_memory_region(flash_mem);
}
}
}
--
2.17.1