[xen staging] EFI: always map EfiRuntimeServices{Code,Data}

[patchbot@xxxxxxx]

commit e3abdc626a732c780f54c783075694c3f951edae
Author:     Sergey Temerkhanov <s.temerkhanov@xxxxxxxxx>
AuthorDate: Wed Feb 2 10:24:56 2022 +0100
Commit:     Jan Beulich <jbeulich@xxxxxxxx>
CommitDate: Wed Feb 2 10:24:56 2022 +0100

    EFI: always map EfiRuntimeServices{Code,Data}
    
    This helps overcome problems observed with some UEFI implementations
    which don't set the Attributes field in memery descriptors properly.
    
    Signed-off-by: Sergey Temerkhanov <s.temerkhanov@xxxxxxxxx>
    Signed-off-by: Jan Beulich <jbeulich@xxxxxxxx>
    Reviewed-by: Luca Fancellu <luca.fancellu@xxxxxxx>
    Tested-by: Luca Fancellu <luca.fancellu@xxxxxxx>
    Reviewed-by: Julien Grall <jgrall@xxxxxxxxxx>
---
 xen/common/efi/boot.c | 41 +++++++++++++++++++++++++++++++++++------
 1 file changed, 35 insertions(+), 6 deletions(-)

diff --git a/xen/common/efi/boot.c b/xen/common/efi/boot.c
index 5ceb535ad0..12fd0844bd 100644
--- a/xen/common/efi/boot.c
+++ b/xen/common/efi/boot.c
@@ -1094,7 +1094,13 @@ static void __init efi_exit_boot(EFI_HANDLE ImageHandle, 
EFI_SYSTEM_TABLE *Syste
     {
         EFI_MEMORY_DESCRIPTOR *desc = efi_memmap + i;
 
-        if ( desc->Attribute & EFI_MEMORY_RUNTIME )
+        /*
+         * Runtime services regions are always mapped here.
+         * Attributes may be adjusted in efi_init_memory().
+         */
+        if ( (desc->Attribute & EFI_MEMORY_RUNTIME) ||
+             desc->Type == EfiRuntimeServicesCode ||
+             desc->Type == EfiRuntimeServicesData )
             desc->VirtualStart = desc->PhysicalStart;
         else
             desc->VirtualStart = INVALID_VIRTUAL_ADDRESS;
@@ -1545,13 +1551,36 @@ void __init efi_init_memory(void)
                     ROUNDUP(desc->PhysicalStart + len, PAGE_SIZE));
         }
 
-        if ( !efi_enabled(EFI_RS) ||
-             (!(desc->Attribute & EFI_MEMORY_RUNTIME) &&
-              (!map_bs ||
-               (desc->Type != EfiBootServicesCode &&
-                desc->Type != EfiBootServicesData))) )
+        if ( !efi_enabled(EFI_RS) )
             continue;
 
+        if ( !(desc->Attribute & EFI_MEMORY_RUNTIME) )
+        {
+            switch ( desc->Type )
+            {
+            default:
+                continue;
+
+            /*
+             * Adjust runtime services regions. Keep in sync with
+             * efi_exit_boot().
+             */
+            case EfiRuntimeServicesCode:
+            case EfiRuntimeServicesData:
+                printk(XENLOG_WARNING
+                       "Setting RUNTIME attribute for %013" PRIx64 "-%013" 
PRIx64 "\n",
+                       desc->PhysicalStart, desc->PhysicalStart + len - 1);
+                desc->Attribute |= EFI_MEMORY_RUNTIME;
+                break;
+
+            case EfiBootServicesCode:
+            case EfiBootServicesData:
+                if ( !map_bs )
+                    continue;
+                break;
+            }
+        }
+
         desc->VirtualStart = INVALID_VIRTUAL_ADDRESS;
 
         smfn = PFN_DOWN(desc->PhysicalStart);
--
generated by git-patchbot for /home/xen/git/xen.git#staging