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Date: Fri, 18 Nov 2022 16:54:26 -0600
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Subject: [STILL CRASHING] Re: [edk2-devel] [PATCH v3 1/1] MdeModulePkg/UsbBusDxe: Rebuild the description table after Reset Device
To: devel@edk2.groups.io, srikumar-subramanian@hpe.com,
 Guomin Jiang <guomin.jiang@intel.com>
References: <DM6PR11MB295562CF0388FFBA663E367D9D7F0@DM6PR11MB2955.namprd11.prod.outlook.com>
 <18532.1607517516172259087@groups.io>
From: "Jeremy Linton" <jeremy.linton@arm.com>
In-Reply-To: <18532.1607517516172259087@groups.io>
Content-Language: en-US
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Content-Transfer-Encoding: quoted-printable

Hi,

Dead thread poke, but, its been > 2 years since this problem was pointed=20
out.

Multiple patches have been proposed, including one by me:
https://edk2.groups.io/g/devel/message/58193
and the USB/XHCI reset logic continues to be broken enough that a wide=20
range of USB issues can result in boot crashes. Those crashes are the=20
result of a null pointer in the TrsRing being dereferenced following=20
reset. In fact it is 100% reproducible on seemingly any edk2 platform=20
with a XHCI controller given the right USB device (like the really=20
common JMICRON I pointed out in one of the threads).

I'm not sure this patch is right, because the USB descriptors shouldn't=20
be cached over reset, but something has to be done to fix this problem.


Thanks,




On 12/9/20 06:38, Srikumar Subramanian via groups.io wrote:
> Hi Jiang,
>=20
> Is it the responsibility of the reset routine to know what is wrong with =
the device? And on this topic I would like to know your thoughts on another=
 alternative which is saving the config in XhcPollPortStatusChange before d=
isabling the slot and restoring it after initializing the device slot again=
. My rationale for doing this is that, the reset device state diagram accor=
ding to the specs moves the device from the configured to the default state=
 and does not completely remove device information.
> In this regard is it safe to assume that meta-data such as descriptors sh=
ould be restored. Since in this case a port reset is triggering a device re=
set but because we disable and later initialize a new slot for an existing =
device we lose its configuration which we assume does not change.
>=20
> Let me know your thoughts and inputs on this. And if I needed an immediat=
e solution I would like to know the better option between the one I am prop=
osing right now and the existing suggested solution (which is making a requ=
est to the device again for the descriptors.)
>=20
> diff --git a/MdeModulePkg/Bus/Pci/XhciDxe/XhciSched.c b/MdeModulePkg/Bus/=
Pci/XhciDxe/XhciSched.c
> index 1754a97..d330f21 100644
> --- a/MdeModulePkg/Bus/Pci/XhciDxe/XhciSched.c
> +++ b/MdeModulePkg/Bus/Pci/XhciDxe/XhciSched.c
> @@ -1,5 +1,5 @@
> /**
>=20
> **/
> /** @file
>=20
> @@ -1587,6 +1587,65 @@ XhcMonitorAsyncRequests (
> gBS->RestoreTPL (OldTpl);
> }
>=20
> +/**
> +=C2=A0 =C2=A0 Save the current configuration for the Slot in Host Contro=
ller
> +
> +=C2=A0 =C2=A0 @param Xhc=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0=
 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 The XHCI instance
> +=C2=A0 =C2=A0 @param SlotId=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=
=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0The Slot ID
> +=C2=A0 =C2=A0 @param ActiveAlternateSetting=C2=A0 =C2=A0 =C2=A0 =C2=A0 =
=C2=A0The Alternate interface setting that is part of the device context
> +=C2=A0 =C2=A0 @param ConfDesc=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =
=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0The Configuration Descriptors of t=
he device present in the slot
> +=C2=A0 =C2=A0 @param DevDesc=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =
=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 The Device Descriptor of the devi=
ce present in the slot
> +**/
> +VOID
> +XhcSaveConfig(
> +=C2=A0 IN USB_XHCI_INSTANCE=C2=A0 =C2=A0 *Xhc,
> +=C2=A0 IN UINT8=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =
=C2=A0SlotId,
> +=C2=A0 OUT UINT8=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0*=
*ActiveAlternateSetting,
> +=C2=A0 OUT EFI_USB_CONFIG_DESCRIPTOR ***ConfDesc,
> +=C2=A0 OUT EFI_USB_DEVICE_DESCRIPTOR *DevDesc
> +)
> +{
> +=C2=A0 UINT8 Index;
> +=C2=A0 UINT8 IfIndex;
> +=C2=A0 UINT8 NumInterfaces;
> +=C2=A0 UINT64 ConfSize;
> +=C2=A0 EFI_USB_INTERFACE_DESCRIPTOR *IfDesc;
> +
> +=C2=A0 *DevDesc =3D Xhc->UsbDevContext[SlotId].DevDesc;
> +
> +=C2=A0 if(DevDesc->NumConfigurations=3D=3D0){
> +=C2=A0 =C2=A0 return;
> +=C2=A0 }
> +
> +=C2=A0 *ConfDesc =3D AllocateZeroPool(DevDesc->NumConfigurations * sizeo=
f(EFI_USB_CONFIG_DESCRIPTOR*));
> +
> +=C2=A0 for(Index =3D 0; Index < DevDesc->NumConfigurations; Index++){
> +=C2=A0 =C2=A0 NumInterfaces =3D Xhc->UsbDevContext[SlotId].ConfDesc[Inde=
x]->NumInterfaces;
> +=C2=A0 =C2=A0 IfDesc =3D (EFI_USB_INTERFACE_DESCRIPTOR *)(Xhc->UsbDevCon=
text[SlotId].ConfDesc[Index] + 1);
> +
> +=C2=A0 =C2=A0 // Calculating the size of the configuration descriptor.
> +=C2=A0 =C2=A0 // This is needed since the interface and enpoint descript=
ors are nested within this.
> +=C2=A0 =C2=A0 // See USB_CONFIG_DESCRIPTOR, USB_INTERFACE_DESCRIPTOR, US=
B_ENDPOINT_DESCRIPTOR in MdePkg/Include/IndustryStandard/Usb.h
> +=C2=A0 =C2=A0 // See USB_CONFIG_DESC, USB_INTERFACE_DESC, USB_ENDPOINT_D=
ESC in MdeModulePkg/Bus/Usb/UsbBusDxe/UsbDesc.h
> +=C2=A0 =C2=A0 ConfSize =3D sizeof(Xhc->UsbDevContext[SlotId].ConfDesc[In=
dex]);
> +=C2=A0 =C2=A0 ConfSize +=3D (sizeof(EFI_USB_INTERFACE_DESCRIPTOR) * (Num=
Interfaces));
> +=C2=A0 =C2=A0 for(IfIndex =3D 0; IfIndex < NumInterfaces; IfIndex++){
> +=C2=A0 =C2=A0 =C2=A0 ConfSize +=3D IfDesc->NumEndpoints * sizeof(EFI_USB=
_ENDPOINT_DESCRIPTOR);
> +=C2=A0 =C2=A0 =C2=A0 IfDesc =3D (USB_INTERFACE_DESCRIPTOR *)((UINTN)IfDe=
sc + IfDesc->Length);
> +=C2=A0 =C2=A0 }
> +
> +=C2=A0 =C2=A0 *ConfDesc[Index] =3D AllocateZeroPool(ConfSize);
> +=C2=A0 =C2=A0 CopyMem (*ConfDesc[Index] ,Xhc->UsbDevContext[SlotId].Conf=
Desc[Index], ConfSize);
> +=C2=A0 }
> +
> +=C2=A0 *ActiveAlternateSetting =3D AllocateZeroPool(Xhc->UsbDevContext[S=
lotId].ConfDesc[0]->NumInterfaces * sizeof(UINT8));
> +
> +=C2=A0 CopyMem(*ActiveAlternateSetting, Xhc->UsbDevContext[SlotId].Activ=
eAlternateSetting, Xhc->UsbDevContext[SlotId].ConfDesc[0]->NumInterfaces * =
sizeof(UINT8));
> +
> +}
> +
> /**
> Monitor the port status change. Enable/Disable device slot if there is a =
device attached/detached.
>=20
> @@ -1613,6 +1672,15 @@ XhcPollPortStatusChange (
> UINT8=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0SlotId;
> USB_DEV_ROUTE=C2=A0 =C2=A0 =C2=A0RouteChart;
>=20
> +=C2=A0 EFI_USB_CONFIG_DESCRIPTOR **ConfDescBuffer;
> +=C2=A0 EFI_USB_DEVICE_DESCRIPTOR DevDescBuffer;
> +=C2=A0 UINT8=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0*ActiveAlter=
nateSettingBuffer;
> +
> +=C2=A0 ConfDescBuffer =3D NULL;
> +=C2=A0 ActiveAlternateSettingBuffer =3D NULL;
> +
> Status =3D EFI_SUCCESS;
>=20
> if ((PortState->PortChangeStatus & (USB_PORT_STAT_C_CONNECTION | USB_PORT=
_STAT_C_ENABLE | USB_PORT_STAT_C_OVERCURRENT | USB_PORT_STAT_C_RESET)) =3D=
=3D 0) {
> @@ -1635,6 +1703,14 @@ XhcPollPortStatusChange (
>=20
> SlotId =3D XhcRouteStringToSlotId (Xhc, RouteChart);
> if (SlotId !=3D 0) {
> +
> +=C2=A0 =C2=A0 // Saving the current host controller configuration for re=
use after device reset
> +=C2=A0 =C2=A0 if((PortState->PortChangeStatus & USB_PORT_STAT_C_RESET) !=
=3D 0){
> +=C2=A0 =C2=A0 =C2=A0 XhcSaveConfig(Xhc, SlotId, &ActiveAlternateSettingB=
uffer, &ConfDescBuffer, &DevDescBuffer);
> +=C2=A0 =C2=A0 }
> +
> if (Xhc->HcCParams.Data.Csz =3D=3D 0) {
> Status =3D XhcDisableSlotCmd (Xhc, SlotId);
> } else {
> @@ -1660,11 +1736,23 @@ XhcPollPortStatusChange (
> //
> SlotId =3D XhcRouteStringToSlotId (Xhc, RouteChart);
> if ((SlotId =3D=3D 0) && ((PortState->PortChangeStatus & USB_PORT_STAT_C_=
RESET) !=3D 0)) {
> +
> +
> +=C2=A0 =C2=A0 =C2=A0 // Introducing the SlotId as a new parameter in Xhc=
InitializeDeviceSlot in order to get the
> +=C2=A0 =C2=A0 =C2=A0 // new slotId assigned.
> if (Xhc->HcCParams.Data.Csz =3D=3D 0) {
> -=C2=A0 =C2=A0 =C2=A0 =C2=A0 Status =3D XhcInitializeDeviceSlot (Xhc, Par=
entRouteChart, Port, RouteChart, Speed);
> +=C2=A0 =C2=A0 =C2=A0 =C2=A0 Status =3D XhcInitializeDeviceSlot (Xhc, Par=
entRouteChart, Port, RouteChart, Speed, &SlotId);
> } else {
> -=C2=A0 =C2=A0 =C2=A0 =C2=A0 Status =3D XhcInitializeDeviceSlot64 (Xhc, P=
arentRouteChart, Port, RouteChart, Speed);
> +=C2=A0 =C2=A0 =C2=A0 =C2=A0 Status =3D XhcInitializeDeviceSlot64 (Xhc, P=
arentRouteChart, Port, RouteChart, Speed, &SlotId);
> }
> +
> +=C2=A0 =C2=A0 =C2=A0 if(!EFI_ERROR(Status) && ConfDescBuffer!=3DNULL && =
SlotId!=3D0){
> +=C2=A0 =C2=A0 =C2=A0 =C2=A0 Xhc->UsbDevContext[SlotId].DevDesc =3D DevDe=
scBuffer;
> +=C2=A0 =C2=A0 =C2=A0 =C2=A0 Xhc->UsbDevContext[SlotId].ConfDesc =3D Conf=
DescBuffer;
> +=C2=A0 =C2=A0 =C2=A0 =C2=A0 Xhc->UsbDevContext[SlotId].ActiveAlternateSe=
tting =3D ActiveAlternateSettingBuffer;
> +=C2=A0 =C2=A0 =C2=A0 }
>=20
> +
> }
> }
>=20
> @@ -1987,7 +2075,11 @@ XhcInitializeDeviceSlot (
> IN=C2=A0 USB_DEV_ROUTE=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0Par=
entRouteChart,
> IN=C2=A0 UINT16=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =
=C2=A0 =C2=A0 ParentPort,
> IN=C2=A0 USB_DEV_ROUTE=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0Rou=
teChart,
> -=C2=A0 IN=C2=A0 UINT8=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =
=C2=A0 =C2=A0 =C2=A0 =C2=A0DeviceSpeed
> +=C2=A0 IN=C2=A0 UINT8=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =
=C2=A0 =C2=A0 =C2=A0 =C2=A0DeviceSpeed,
>=20
> +=C2=A0 // OPTIONAL as this need not be used
> +=C2=A0 OPTIONAL OUT UINT8=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 *Slot=
IdStore
>=20
> )
> {
> EFI_STATUS=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =
Status;
> @@ -2175,6 +2267,12 @@ XhcInitializeDeviceSlot (
> Xhc->UsbDevContext[SlotId].XhciDevAddr =3D DeviceAddress;
> }
>=20
> +=C2=A0 if(SlotIdStore !=3D NULL){
> +=C2=A0 *SlotIdStore =3D SlotId;
> +=C2=A0 }
> +
> return Status;
> }
>=20
> @@ -2197,7 +2295,11 @@ XhcInitializeDeviceSlot64 (
> IN=C2=A0 USB_DEV_ROUTE=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0Par=
entRouteChart,
> IN=C2=A0 UINT16=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =
=C2=A0 =C2=A0 ParentPort,
> IN=C2=A0 USB_DEV_ROUTE=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0Rou=
teChart,
> -=C2=A0 IN=C2=A0 UINT8=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =
=C2=A0 =C2=A0 =C2=A0 =C2=A0DeviceSpeed
> +=C2=A0 IN=C2=A0 UINT8=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =
=C2=A0 =C2=A0 =C2=A0 =C2=A0DeviceSpeed,
>=20
> +=C2=A0 // OPTIONAL as this need not be used
> +=C2=A0 OPTIONAL OUT UINT8=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 *Slot=
IdStore
>=20
> )
> {
> EFI_STATUS=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =
Status;
> @@ -2384,6 +2486,13 @@ XhcInitializeDeviceSlot64 (
> DEBUG ((EFI_D_INFO, "=C2=A0 =C2=A0 Address %d assigned successfully\n", D=
eviceAddress));
> Xhc->UsbDevContext[SlotId].XhciDevAddr =3D DeviceAddress;
> }
> +
>=20
> +=C2=A0 if(SlotIdStore !=3D NULL){
> +=C2=A0 *SlotIdStore =3D SlotId;
> +=C2=A0 }
>=20
> +
> return Status;
> }
>=20
> diff --git a/MdeModulePkg/Bus/Pci/XhciDxe/XhciSched.h b/MdeModulePkg/Bus/=
Pci/XhciDxe/XhciSched.h
> index 4da9669..64ef878 100644
> --- a/PurleyPlatPkg/Override/MdeModulePkg/Bus/Pci/XhciDxe/XhciSched.h
> +++ b/PurleyPlatPkg/Override/MdeModulePkg/Bus/Pci/XhciDxe/XhciSched.h
> @@ -1,3 +1,6 @@
> +/**
> +*=C2=A0 CONFIDENTIAL (C) Copyright 2020 Hewlett Packard Enterprise Devel=
opment LP<BR>
> +**/
> /** @file
>=20
> This file contains the definition for XHCI host controller schedule routi=
nes.
> @@ -1120,7 +1123,11 @@ XhcInitializeDeviceSlot (
> IN=C2=A0 USB_DEV_ROUTE=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0Par=
entRouteChart,
> IN=C2=A0 UINT16=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =
=C2=A0 =C2=A0 ParentPort,
> IN=C2=A0 USB_DEV_ROUTE=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0Rou=
teChart,
> -=C2=A0 IN=C2=A0 UINT8=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =
=C2=A0 =C2=A0 =C2=A0 =C2=A0DeviceSpeed
> +=C2=A0 IN=C2=A0 UINT8=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =
=C2=A0 =C2=A0 =C2=A0 =C2=A0DeviceSpeed,
> +=C2=A0 // HPE_EXL_SS_QXCR1001775642
> +=C2=A0 // OPTIONAL as this need not be used
> +=C2=A0 OPTIONAL OUT UINT8=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 *Slot=
IdStore
> +=C2=A0 // HPE_EXL_SS_QXCR1001775642
> );
>=20
> /**
> @@ -1142,7 +1149,11 @@ XhcInitializeDeviceSlot64 (
> IN=C2=A0 USB_DEV_ROUTE=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0Par=
entRouteChart,
> IN=C2=A0 UINT16=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =
=C2=A0 =C2=A0 ParentPort,
> IN=C2=A0 USB_DEV_ROUTE=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0Rou=
teChart,
> -=C2=A0 IN=C2=A0 UINT8=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =
=C2=A0 =C2=A0 =C2=A0 =C2=A0DeviceSpeed
> +=C2=A0 IN=C2=A0 UINT8=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =
=C2=A0 =C2=A0 =C2=A0 =C2=A0DeviceSpeed,
>=20
> +=C2=A0 // OPTIONAL as this need not be used
> +=C2=A0 OPTIONAL OUT UINT8=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 *Slot=
IdStore
>=20
> );
>=20
> /**
> @@ -1458,4 +1469,24 @@ XhcCreateTransferTrb (
> IN URB=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=
=A0 =C2=A0 =C2=A0 =C2=A0 *Urb
> );
>=20
> +/**
> +=C2=A0 =C2=A0 Save the current configuration for the Slot in Host Contro=
ller
> +
> +=C2=A0 =C2=A0 @param Xhc=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0=
 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 The XHCI instance
> +=C2=A0 =C2=A0 @param SlotId=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=
=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0The Slot ID
> +=C2=A0 =C2=A0 @param ActiveAlternateSetting=C2=A0 =C2=A0 =C2=A0 =C2=A0 =
=C2=A0The Alternate interface setting that is part of the device context
> +=C2=A0 =C2=A0 @param ConfDesc=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =
=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0The Configuration Descriptors of t=
he device present in the slot
> +=C2=A0 =C2=A0 @param DevDesc=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =
=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 The Device Descriptor of the devi=
ce present in the slot
> +**/
> +VOID
> +XhcSaveConfig(
> +=C2=A0 IN USB_XHCI_INSTANCE=C2=A0 =C2=A0 *Xhc,
> +=C2=A0 IN UINT8=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =
=C2=A0SlotId,
> +=C2=A0 OUT UINT8=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0*=
*ActiveAlternateSetting,
> +=C2=A0 OUT EFI_USB_CONFIG_DESCRIPTOR ***ConfDesc,
> +=C2=A0 OUT EFI_USB_DEVICE_DESCRIPTOR *DevDesc
> +);
> +
>=20
>=20
>=20
>=20
>=20
>=20