From f796c60e6e7b9130960ee0982feb25ca4994df2a Mon Sep 17 00:00:00 2001
From: Philipp Schuster <philipp.schuster@cyberus-technology.de>
Date: Mon, 13 Apr 2026 09:14:35 +0200
Subject: [PATCH] OvmfPkg/VirtioBlkDxe: protect SynchronousRequest against
 interrupts (e.g., timer)

---
 OvmfPkg/VirtioBlkDxe/VirtioBlk.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/OvmfPkg/VirtioBlkDxe/VirtioBlk.c b/OvmfPkg/VirtioBlkDxe/VirtioBlk.c
index f881cde4c5db..3bee2229c088 100644
--- a/OvmfPkg/VirtioBlkDxe/VirtioBlk.c
+++ b/OvmfPkg/VirtioBlkDxe/VirtioBlk.c
@@ -253,6 +253,7 @@ SynchronousRequest (
   EFI_PHYSICAL_ADDRESS     RequestDeviceAddress;
   EFI_STATUS               Status;
   EFI_STATUS               UnmapStatus;
+  EFI_TPL                  CurrentTpl;
 
   BlockSize = Dev->BlockIoMedia.BlockSize;
 
@@ -365,6 +366,8 @@ SynchronousRequest (
     goto UnmapDataBuffer;
   }
 
+  CurrentTpl = gBS->RaiseTPL (TPL_NOTIFY);
+
   VirtioPrepare (&Dev->Ring, &Indices);
 
   //
@@ -438,6 +441,7 @@ SynchronousRequest (
     Status = EFI_DEVICE_ERROR;
   }
 
+  gBS->RestoreTPL (CurrentTpl);
   Dev->VirtIo->UnmapSharedBuffer (Dev->VirtIo, StatusMapping);
 
 UnmapDataBuffer: