diff mbox series

[2/2,v2] efi_loader: Disable devices before handing over control

Message ID 20201021220421.1926180-2-ilias.apalodimas@linaro.org
State New
Headers show
Series [1/2,v2] efi_loader: Sort header file ordering | expand

Commit Message

Ilias Apalodimas Oct. 21, 2020, 10:04 p.m. UTC
U-Boot Driver Model is supposed to remove devices with either
DM_REMOVE_ACTIVE_DMA or DM_REMOVE_OS_PREPARE flags set, before exiting.
Our bootm command does that by explicitly calling calling
"dm_remove_devices_flags(DM_REMOVE_ACTIVE_ALL);" and we also disable any
USB devices.

The EFI equivalent is doing none of those at the moment. As a result
probing an fTPM driver now renders it unusable in Linux. During our
(*probe) callback we open a session with OP-TEE, which is supposed to
close with our (*remove) callback. Since the (*remove) is never called,
once we boot into Linux and try to probe the device again we are getting
a busy error response. Moreover all uclass (*preremove) functions won't
run.

So let's fix this by mimicking what bootm does and disconnect devices
when efi_exit_boot_services() is called.

Signed-off-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>

---
changes since v1:
- Add a patch sorting the .h files inclusions
- Fix compilation errors for sandbox_spl_defconfig
- TravisCI: https://travis-ci.com/github/apalos/u-boot/builds/191447335
 lib/efi_loader/efi_boottime.c | 6 ++++++
 1 file changed, 6 insertions(+)

-- 
2.28.0

Comments

Ilias Apalodimas Oct. 22, 2020, 4:37 a.m. UTC | #1
+cc Mark


On Thu, 22 Oct 2020 at 01:04, Ilias Apalodimas
<ilias.apalodimas@linaro.org> wrote:
>

> U-Boot Driver Model is supposed to remove devices with either

> DM_REMOVE_ACTIVE_DMA or DM_REMOVE_OS_PREPARE flags set, before exiting.

> Our bootm command does that by explicitly calling calling

> "dm_remove_devices_flags(DM_REMOVE_ACTIVE_ALL);" and we also disable any

> USB devices.

>

> The EFI equivalent is doing none of those at the moment. As a result

> probing an fTPM driver now renders it unusable in Linux. During our

> (*probe) callback we open a session with OP-TEE, which is supposed to

> close with our (*remove) callback. Since the (*remove) is never called,

> once we boot into Linux and try to probe the device again we are getting

> a busy error response. Moreover all uclass (*preremove) functions won't

> run.

>

> So let's fix this by mimicking what bootm does and disconnect devices

> when efi_exit_boot_services() is called.

>

> Signed-off-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>

> ---

> changes since v1:

> - Add a patch sorting the .h files inclusions

> - Fix compilation errors for sandbox_spl_defconfig

> - TravisCI: https://travis-ci.com/github/apalos/u-boot/builds/191447335

>  lib/efi_loader/efi_boottime.c | 6 ++++++

>  1 file changed, 6 insertions(+)

>

> diff --git a/lib/efi_loader/efi_boottime.c b/lib/efi_loader/efi_boottime.c

> index 2896c3ea5aa8..b26ac9fbfc79 100644

> --- a/lib/efi_loader/efi_boottime.c

> +++ b/lib/efi_loader/efi_boottime.c

> @@ -8,6 +8,8 @@

>  #include <common.h>

>  #include <bootm.h>

>  #include <div64.h>

> +#include <dm/device.h>

> +#include <dm/root.h>

>  #include <efi_loader.h>

>  #include <irq_func.h>

>  #include <log.h>

> @@ -15,6 +17,7 @@

>  #include <pe.h>

>  #include <time.h>

>  #include <u-boot/crc.h>

> +#include <usb.h>

>  #include <watchdog.h>

>  #include <linux/libfdt_env.h>

>

> @@ -1993,7 +1996,10 @@ static efi_status_t EFIAPI efi_exit_boot_services(efi_handle_t image_handle,

>                         list_del(&evt->link);

>         }

>

> +       if IS_ENABLED(CONFIG_USB_DEVICE)

> +               udc_disconnect();

>         board_quiesce_devices();

> +       dm_remove_devices_flags(DM_REMOVE_ACTIVE_ALL);

>

>         /* Patch out unsupported runtime function */

>         efi_runtime_detach();

> --

> 2.28.0

>
Heinrich Schuchardt Oct. 22, 2020, 6:11 a.m. UTC | #2
On 10/22/20 12:04 AM, Ilias Apalodimas wrote:
> U-Boot Driver Model is supposed to remove devices with either

> DM_REMOVE_ACTIVE_DMA or DM_REMOVE_OS_PREPARE flags set, before exiting.

> Our bootm command does that by explicitly calling calling

> "dm_remove_devices_flags(DM_REMOVE_ACTIVE_ALL);" and we also disable any

> USB devices.

>

> The EFI equivalent is doing none of those at the moment. As a result

> probing an fTPM driver now renders it unusable in Linux. During our

> (*probe) callback we open a session with OP-TEE, which is supposed to

> close with our (*remove) callback. Since the (*remove) is never called,

> once we boot into Linux and try to probe the device again we are getting

> a busy error response. Moreover all uclass (*preremove) functions won't

> run.

>

> So let's fix this by mimicking what bootm does and disconnect devices

> when efi_exit_boot_services() is called.

>

> Signed-off-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>


Reviewed-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
diff mbox series

Patch

diff --git a/lib/efi_loader/efi_boottime.c b/lib/efi_loader/efi_boottime.c
index 2896c3ea5aa8..b26ac9fbfc79 100644
--- a/lib/efi_loader/efi_boottime.c
+++ b/lib/efi_loader/efi_boottime.c
@@ -8,6 +8,8 @@ 
 #include <common.h>
 #include <bootm.h>
 #include <div64.h>
+#include <dm/device.h>
+#include <dm/root.h>
 #include <efi_loader.h>
 #include <irq_func.h>
 #include <log.h>
@@ -15,6 +17,7 @@ 
 #include <pe.h>
 #include <time.h>
 #include <u-boot/crc.h>
+#include <usb.h>
 #include <watchdog.h>
 #include <linux/libfdt_env.h>
 
@@ -1993,7 +1996,10 @@  static efi_status_t EFIAPI efi_exit_boot_services(efi_handle_t image_handle,
 			list_del(&evt->link);
 	}
 
+	if IS_ENABLED(CONFIG_USB_DEVICE)
+		udc_disconnect();
 	board_quiesce_devices();
+	dm_remove_devices_flags(DM_REMOVE_ACTIVE_ALL);
 
 	/* Patch out unsupported runtime function */
 	efi_runtime_detach();