From 89d413731dc99a509d4dc6e942e519ebdb0c3487 Mon Sep 17 00:00:00 2001
From: joe <37425738+JoeLopez333@users.noreply.github.com>
Date: Mon, 14 Aug 2023 15:27:08 -0700
Subject: NetworkPkg/SnpDxe: Shutdown SnpDxe on BeforeExitBootServices Event.

SnpDxe registers for an ExitBootServices callback and runs the
PXE_OPCODE_SHUTDOWN and PXE_OPCODE_STOP commands for any network
controllers that the driver is attached to.

Register the SnpDxe callback for gEfiEventBeforeExitBootServicesGuid
instead of gEfiEventExitBootServicesGuid to ensure the correct ordering:

1. ExitBootServices event
2. Network card shutdown sequence is completed

Also, close the event to prevent rerunning the shutdown if multiple
ExitBootServices events need to be called by the OS.

Signed-off-by: Aaron Pop <aaronpop@microsoft.com>
---
 NetworkPkg/SnpDxe/Snp.c      | 6 +++++-
 NetworkPkg/SnpDxe/SnpDxe.inf | 2 +-
 2 files changed, 6 insertions(+), 2 deletions(-)

(limited to 'NetworkPkg')

diff --git a/NetworkPkg/SnpDxe/Snp.c b/NetworkPkg/SnpDxe/Snp.c
index 95361c3cd3..09d6c8fc99 100644
--- a/NetworkPkg/SnpDxe/Snp.c
+++ b/NetworkPkg/SnpDxe/Snp.c
@@ -32,6 +32,10 @@ SnpNotifyExitBootServices (
   //
   PxeShutdown (Snp);
   PxeStop (Snp);
+
+  // Since BeforeExitBootServices is run on each call, close event
+  // to prevent reentry.
+  gBS->CloseEvent (Event);
 }
 
 /**
@@ -655,7 +659,7 @@ SimpleNetworkDriverStart (
                     TPL_CALLBACK,
                     SnpNotifyExitBootServices,
                     Snp,
-                    &gEfiEventExitBootServicesGuid,
+                    &gEfiEventBeforeExitBootServicesGuid,
                     &Snp->ExitBootServicesEvent
                     );
     if (EFI_ERROR (Status)) {
diff --git a/NetworkPkg/SnpDxe/SnpDxe.inf b/NetworkPkg/SnpDxe/SnpDxe.inf
index d16f1888b3..e1afd46dfe 100644
--- a/NetworkPkg/SnpDxe/SnpDxe.inf
+++ b/NetworkPkg/SnpDxe/SnpDxe.inf
@@ -65,7 +65,7 @@
   NetLib
 
 [Guids]
-  gEfiEventExitBootServicesGuid                 ## SOMETIMES_CONSUMES ## Event
+  gEfiEventBeforeExitBootServicesGuid           ## SOMETIMES_CONSUMES ## Event
 
 [Protocols]
   gEfiSimpleNetworkProtocolGuid                 ## BY_START
-- 
cgit