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MdeModulePkg PartitionDxe: Add Re-entry handling logic for BindingStop 

There are scenario when the BindingStop service of PartitionDxe driver be
re-entered.

An example will be ejecting a DVD from a SATA DVDROM and then run
"reconnect -r" under shell. In this specific case, part of the calling
stack will be:

PartitionDriverBindingStop() (PartitionDxe) ->
Stop first child handle (PartitionDxe) ->
ScsiDiskFlushBlocksEx() (ScsiDiskDxe) ->
A media change is detected (ScsiDiskDxe) ->
Reinstall of BlockIO(2) protocols (ScsiDiskDxe) ->
Entering PartitionDriverBindingStop() again (PartitionDxe) ->
Potential risk of referencing already stopped child handle (PartitionDxe)
...

The current code has potential issue of referencing of already stopped
child handle. This commit adds re-entry handling logic to resolve such
issue.

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Hao Wu <hao.a.wu@intel.com>
Reviewed-by: Feng Tian <feng.tian@intel.com>
This commit is contained in:
Hao Wu 2016-03-11 15:33:54 +08:00
parent d4de4f99da
commit e33257215b
2 changed files with 110 additions and 21 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

82
MdeModulePkg/Universal/Disk/PartitionDxe/Partition.c
View File

@ -407,6 +407,16 @@ PartitionDriverBindingStop (
Private = NULL;
if (NumberOfChildren == 0) {
//
// In the case of re-entry of the PartitionDriverBindingStop, the
// NumberOfChildren may not reflect the actual number of children on the
// bus driver. Hence, additional check is needed here.
//
if (HasChildren (ControllerHandle)) {
DEBUG((EFI_D_ERROR, "PartitionDriverBindingStop: Still has child.\n"));
return EFI_DEVICE_ERROR;
}
//
// Close the bus driver
//
@ -459,8 +469,25 @@ PartitionDriverBindingStop (
Private = PARTITION_DEVICE_FROM_BLOCK_IO_THIS (BlockIo);
if (Private->InStop) {
//
// If the child handle is going to be stopped again during the re-entry
// of DriverBindingStop, just do nothing.
//
break;
}
Private->InStop = TRUE;
Status = gBS->CloseProtocol (
BlockIo->FlushBlocks (BlockIo);
if (BlockIo2 != NULL) {
Status = BlockIo2->FlushBlocksEx (BlockIo2, NULL);
DEBUG((EFI_D_ERROR, "PartitionDriverBindingStop: FlushBlocksEx returned with %r\n", Status));
} else {
Status = EFI_SUCCESS;
}
gBS->CloseProtocol (
ControllerHandle,
&gEfiDiskIoProtocolGuid,
This->DriverBindingHandle,
@ -472,8 +499,13 @@ PartitionDriverBindingStop (
// Remove the BlockIo2 Protocol if has.
//
if (BlockIo2 != NULL) {
BlockIo->FlushBlocks (BlockIo);
BlockIo2->FlushBlocksEx (BlockIo2, NULL);
//
// Some device drivers might re-install the BlockIO(2) protocols for a
// media change condition. Therefore, if the FlushBlocksEx returned with
// EFI_MEDIA_CHANGED, just let the BindingStop fail to avoid potential
// reference of already stopped child handle.
//
if (Status != EFI_MEDIA_CHANGED) {
Status = gBS->UninstallMultipleProtocolInterfaces (
ChildHandleBuffer[Index],
&gEfiDevicePathProtocolGuid,
@ -486,8 +518,8 @@ PartitionDriverBindingStop (
NULL,
NULL
);
}
} else {
BlockIo->FlushBlocks (BlockIo);
Status = gBS->UninstallMultipleProtocolInterfaces (
ChildHandleBuffer[Index],
&gEfiDevicePathProtocolGuid,
@ -501,6 +533,7 @@ PartitionDriverBindingStop (
}
if (EFI_ERROR (Status)) {
Private->InStop = FALSE;
gBS->OpenProtocol (
ControllerHandle,
&gEfiDiskIoProtocolGuid,
@ -516,6 +549,9 @@ PartitionDriverBindingStop (
if (EFI_ERROR (Status)) {
AllChildrenStopped = FALSE;
if (Status == EFI_MEDIA_CHANGED) {
break;
}
}
}
@ -1263,3 +1299,41 @@ InitializePartition (
return Status;
}
/**
Test to see if there is any child on ControllerHandle.
@param[in] ControllerHandle Handle of device to test.
@retval TRUE There are children on the ControllerHandle.
@retval FALSE No child is on the ControllerHandle.
**/
BOOLEAN
HasChildren (
IN EFI_HANDLE ControllerHandle
)
{
EFI_OPEN_PROTOCOL_INFORMATION_ENTRY *OpenInfoBuffer;
UINTN EntryCount;
EFI_STATUS Status;
UINTN Index;
Status = gBS->OpenProtocolInformation (
ControllerHandle,
&gEfiDiskIoProtocolGuid,
&OpenInfoBuffer,
&EntryCount
);
ASSERT_EFI_ERROR (Status);
for (Index = 0; Index < EntryCount; Index++) {
if ((OpenInfoBuffer[Index].Attributes & EFI_OPEN_PROTOCOL_BY_CHILD_CONTROLLER) != 0) {
break;
}
}
FreePool (OpenInfoBuffer);
return (BOOLEAN) (Index < EntryCount);
}

15
MdeModulePkg/Universal/Disk/PartitionDxe/Partition.h
View File

@ -61,6 +61,7 @@ typedef struct {
UINT64 Start;
UINT64 End;
UINT32 BlockSize;
BOOLEAN InStop;
EFI_GUID *EspGuid;
@ -345,6 +346,20 @@ PartitionInstallChildHandle (
IN BOOLEAN InstallEspGuid
);
/**
Test to see if there is any child on ControllerHandle.
@param[in] ControllerHandle Handle of device to test.
@retval TRUE There are children on the ControllerHandle.
@retval FALSE No child is on the ControllerHandle.
**/
BOOLEAN
HasChildren (
IN EFI_HANDLE ControllerHandle
);
/**
Install child handles if the Handle supports GPT partition structure.