blob: 7ddecd0b62a99653b638193ee1c7da69bb718d7e (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
|
/** @file
UEFI Dxe DebugLib constructor that prevent some debug service after ExitBootServices event,
because some pointer is nulled at that phase.
Copyright (c) 2018, Microsoft Corporation
Copyright (c) 2015 - 2019, Intel Corporation. All rights reserved.<BR>
SPDX-License-Identifier: BSD-2-Clause-Patent
**/
#include <Uefi.h>
#include <Library/BaseLib.h>
#include <Library/BaseMemoryLib.h>
//
// BOOLEAN value to indicate if it is at the post ExitBootServices pahse
//
BOOLEAN mPostEBS = FALSE;
static EFI_EVENT mExitBootServicesEvent;
//
// Pointer to SystemTable
// This library instance may have a cycle consume with UefiBootServicesTableLib
// because of the constructors.
//
EFI_BOOT_SERVICES *mDebugBS;
/**
This routine sets the mPostEBS for exit boot servies true
to prevent DebugPort protocol dereferences when the pointer is nulled.
@param Event Event whose notification function is being invoked.
@param Context Pointer to the notification function's context.
**/
static
VOID
EFIAPI
UefiDebugLibDebugPortProtocolExitBootServicesCallback (
EFI_EVENT Event,
VOID *Context
)
{
mPostEBS = TRUE;
return;
}
/**
The constructor gets the pointers to boot services table.
And create a event to indicate it is after ExitBootServices.
@param ImageHandle The firmware allocated handle for the EFI image.
@param SystemTable A pointer to the EFI System Table.
@retval EFI_SUCCESS The constructor always returns EFI_SUCCESS.
**/
EFI_STATUS
EFIAPI
DxeDebugLibConstructor (
IN EFI_HANDLE ImageHandle,
IN EFI_SYSTEM_TABLE *SystemTable
)
{
mDebugBS = SystemTable->BootServices;
mDebugBS->CreateEvent (
EVT_SIGNAL_EXIT_BOOT_SERVICES,
TPL_NOTIFY,
UefiDebugLibDebugPortProtocolExitBootServicesCallback,
NULL,
&mExitBootServicesEvent
);
return EFI_SUCCESS;
}
/**
The destructor closes Exit Boot Services Event.
@param ImageHandle The firmware allocated handle for the EFI image.
@param SystemTable A pointer to the EFI System Table.
@retval EFI_SUCCESS The destructor always returns EFI_SUCCESS.
**/
EFI_STATUS
EFIAPI
DxeDebugLibDestructor (
IN EFI_HANDLE ImageHandle,
IN EFI_SYSTEM_TABLE *SystemTable
)
{
if (mExitBootServicesEvent != NULL) {
SystemTable->BootServices->CloseEvent (mExitBootServicesEvent);
}
return EFI_SUCCESS;
}
|