1 files changed, 17 insertions, 11 deletions

diff --git a/docs/specs/acpi_hest_ghes.rst b/docs/specs/acpi_hest_ghes.rst
index c3e9f8d..aaf7b1a 100644
--- a/docs/specs/acpi_hest_ghes.rst
+++ b/docs/specs/acpi_hest_ghes.rst
@@ -89,12 +89,21 @@ Design Details
     addresses in the "error_block_address" fields with a pointer to the
     respective "Error Status Data Block" in the "etc/hardware_errors" blob.
 
-(8) QEMU defines a third and write-only fw_cfg blob which is called
-    "etc/hardware_errors_addr". Through that blob, the firmware can send back
-    the guest-side allocation addresses to QEMU. The "etc/hardware_errors_addr"
-    blob contains a 8-byte entry. QEMU generates a single WRITE_POINTER command
-    for the firmware. The firmware will write back the start address of
-    "etc/hardware_errors" blob to the fw_cfg file "etc/hardware_errors_addr".
+(8) QEMU defines a third and write-only fw_cfg blob to store the location
+    where the error block offsets, read ack registers and CPER records are
+    stored.
+
+    Up to QEMU 9.2, the location was at "etc/hardware_errors_addr", and
+    contains a GPA for the beginning of "etc/hardware_errors".
+
+    Newer versions place the location at "etc/acpi_table_hest_addr",
+    pointing to the GPA of the HEST table.
+
+    Using above mentioned 'fw_cfg' files, the firmware can send back the
+    guest-side allocation addresses to QEMU. They contain a 8-byte entry.
+    QEMU generates a single WRITE_POINTER command for the firmware. The
+    firmware will write back the start address of either "etc/hardware_errors"
+    or HEST table at the corresponding fw_cfg file.
 
 (9) When QEMU gets a SIGBUS from the kernel, QEMU writes CPER into corresponding
     "Error Status Data Block", guest memory, and then injects platform specific
@@ -105,8 +114,5 @@ Design Details
      kernel, on receiving notification, guest APEI driver could read the CPER error
      and take appropriate action.
 
-(11) kvm_arch_on_sigbus_vcpu() uses source_id as index in "etc/hardware_errors" to
-     find out "Error Status Data Block" entry corresponding to error source. So supported
-     source_id values should be assigned here and not be changed afterwards to make sure
-     that guest will write error into expected "Error Status Data Block" even if guest was
-     migrated to a newer QEMU.
+(11) kvm_arch_on_sigbus_vcpu() reports RAS errors via a SEA notifications,
+     when a SIGBUS event is triggered.