* [PATCH v2 1/2] USB: core: Make port power cycle a seperate helper function
@ 2019-11-29 17:41 Kai-Heng Feng
2019-11-29 17:41 ` [PATCH v2 2/2] USB: core: Attempt power cycle port when it's in eSS.Disabled state Kai-Heng Feng
0 siblings, 1 reply; 6+ messages in thread
From: Kai-Heng Feng @ 2019-11-29 17:41 UTC (permalink / raw)
To: gregkh; +Cc: stern, linux-usb, linux-kernel, Kai-Heng Feng
Add a new function, hub_port_power_cycle() to power cycle port's power.
It'll be used by a following patch.
In addition to that, check the return value of usb_hub_set_port_power(),
so we don't need to wait if the set power operation fails.
Furthermore, remove parameter *hdev from usb_hub_set_port_power(), since
we can get *hdev from *hub directly.
Signed-off-by: Kai-Heng Feng <kai.heng.feng@canonical.com>
---
v2:
- No change.
drivers/usb/core/hub.c | 30 ++++++++++++++++++++++++------
drivers/usb/core/hub.h | 3 +--
drivers/usb/core/port.c | 4 ++--
3 files changed, 27 insertions(+), 10 deletions(-)
diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c
index 1709895387b9..6b6cd76ac5e6 100644
--- a/drivers/usb/core/hub.c
+++ b/drivers/usb/core/hub.c
@@ -817,9 +817,9 @@ static void hub_tt_work(struct work_struct *work)
*
* Return: 0 if successful. A negative error code otherwise.
*/
-int usb_hub_set_port_power(struct usb_device *hdev, struct usb_hub *hub,
- int port1, bool set)
+int usb_hub_set_port_power(struct usb_hub *hub, int port1, bool set)
{
+ struct usb_device *hdev = hub->hdev;
int ret;
if (set)
@@ -2739,6 +2739,27 @@ static bool hub_port_warm_reset_required(struct usb_hub *hub, int port1,
|| link_state == USB_SS_PORT_LS_COMP_MOD;
}
+static void hub_port_power_cycle(struct usb_hub *hub, int port1)
+{
+ struct usb_port *port_dev = hub->ports[port1 - 1];
+ int ret;
+
+ ret = usb_hub_set_port_power(hub, port1, false);
+ if (ret) {
+ dev_info(&port_dev->dev, "failed to disable port power\n");
+ return;
+ }
+
+ msleep(2 * hub_power_on_good_delay(hub));
+ ret = usb_hub_set_port_power(hub, port1, true);
+ if (ret) {
+ dev_info(&port_dev->dev, "failed to enable port power\n");
+ return;
+ }
+
+ msleep(hub_power_on_good_delay(hub));
+}
+
static int hub_port_wait_reset(struct usb_hub *hub, int port1,
struct usb_device *udev, unsigned int delay, bool warm)
{
@@ -5216,10 +5237,7 @@ static void hub_port_connect(struct usb_hub *hub, int port1, u16 portstatus,
/* When halfway through our retry count, power-cycle the port */
if (i == (SET_CONFIG_TRIES / 2) - 1) {
dev_info(&port_dev->dev, "attempt power cycle\n");
- usb_hub_set_port_power(hdev, hub, port1, false);
- msleep(2 * hub_power_on_good_delay(hub));
- usb_hub_set_port_power(hdev, hub, port1, true);
- msleep(hub_power_on_good_delay(hub));
+ hub_port_power_cycle(hub, port1);
}
}
if (hub->hdev->parent ||
diff --git a/drivers/usb/core/hub.h b/drivers/usb/core/hub.h
index a9e24e4b8df1..325a55637a6f 100644
--- a/drivers/usb/core/hub.h
+++ b/drivers/usb/core/hub.h
@@ -113,8 +113,7 @@ extern int usb_hub_create_port_device(struct usb_hub *hub,
int port1);
extern void usb_hub_remove_port_device(struct usb_hub *hub,
int port1);
-extern int usb_hub_set_port_power(struct usb_device *hdev, struct usb_hub *hub,
- int port1, bool set);
+extern int usb_hub_set_port_power(struct usb_hub *hub, int port1, bool set);
extern struct usb_hub *usb_hub_to_struct_hub(struct usb_device *hdev);
extern int hub_port_debounce(struct usb_hub *hub, int port1,
bool must_be_connected);
diff --git a/drivers/usb/core/port.c b/drivers/usb/core/port.c
index bbbb35fa639f..0fc6f24c6da1 100644
--- a/drivers/usb/core/port.c
+++ b/drivers/usb/core/port.c
@@ -214,7 +214,7 @@ static int usb_port_runtime_resume(struct device *dev)
pm_runtime_get_sync(&peer->dev);
usb_autopm_get_interface(intf);
- retval = usb_hub_set_port_power(hdev, hub, port1, true);
+ retval = usb_hub_set_port_power(hub, port1, true);
msleep(hub_power_on_good_delay(hub));
if (udev && !retval) {
/*
@@ -267,7 +267,7 @@ static int usb_port_runtime_suspend(struct device *dev)
return -EBUSY;
usb_autopm_get_interface(intf);
- retval = usb_hub_set_port_power(hdev, hub, port1, false);
+ retval = usb_hub_set_port_power(hub, port1, false);
usb_clear_port_feature(hdev, port1, USB_PORT_FEAT_C_CONNECTION);
if (!port_dev->is_superspeed)
usb_clear_port_feature(hdev, port1, USB_PORT_FEAT_C_ENABLE);
--
2.17.1
^ permalink raw reply related [flat|nested] 6+ messages in thread* [PATCH v2 2/2] USB: core: Attempt power cycle port when it's in eSS.Disabled state
2019-11-29 17:41 [PATCH v2 1/2] USB: core: Make port power cycle a seperate helper function Kai-Heng Feng
@ 2019-11-29 17:41 ` Kai-Heng Feng
2019-12-11 13:45 ` Kai-Heng Feng
0 siblings, 1 reply; 6+ messages in thread
From: Kai-Heng Feng @ 2019-11-29 17:41 UTC (permalink / raw)
To: gregkh; +Cc: stern, linux-usb, linux-kernel, Kai-Heng Feng
On Dell TB16, Realtek USB ethernet (r8152) connects to an SMSC hub which
then connects to ASMedia xHCI's root hub:
/: Bus 04.Port 1: Dev 1, Class=root_hub, Driver=xhci_hcd/2p, 5000M
|__ Port 1: Dev 2, If 0, Class=Hub, Driver=hub/7p, 5000M
|__ Port 2: Dev 3, If 0, Class=Vendor Specific Class, Driver=r8152, 5000M
Bus 004 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 004 Device 002: ID 0424:5537 Standard Microsystems Corp. USB5537B
Bus 004 Device 003: ID 0bda:8153 Realtek Semiconductor Corp. RTL8153 Gigabit Ethernet Adapter
The SMSC hub may disconnect after system resume from suspend. When this
happens, the reset resume attempt fails, and the last resort to disable
the port and see something comes up later, also fails.
When the issue occurs, the link state stays in eSS.Disabled state
despite the warm reset attempts. Accoding to spec this can be caused by
invalid VBus, after some expiremets, the SMSC hub can be brought back
after a powercycle.
So let's power cycle the port at the end of reset resume attempt, if
it's in eSS.Disabled state.
Signed-off-by: Kai-Heng Feng <kai.heng.feng@canonical.com>
---
v2:
- Lower dev_info() to dev_dbg().
drivers/usb/core/hub.c | 16 ++++++++++++++++
1 file changed, 16 insertions(+)
diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c
index 6b6cd76ac5e6..a2e6001046f5 100644
--- a/drivers/usb/core/hub.c
+++ b/drivers/usb/core/hub.c
@@ -2739,6 +2739,18 @@ static bool hub_port_warm_reset_required(struct usb_hub *hub, int port1,
|| link_state == USB_SS_PORT_LS_COMP_MOD;
}
+static bool hub_port_power_cycle_required(struct usb_hub *hub, int port1,
+ u16 portstatus)
+{
+ u16 link_state;
+
+ if (!hub_is_superspeed(hub->hdev))
+ return false;
+
+ link_state = portstatus & USB_PORT_STAT_LINK_STATE;
+ return link_state == USB_SS_PORT_LS_SS_DISABLED;
+}
+
static void hub_port_power_cycle(struct usb_hub *hub, int port1)
{
struct usb_port *port_dev = hub->ports[port1 - 1];
@@ -3601,6 +3613,10 @@ int usb_port_resume(struct usb_device *udev, pm_message_t msg)
if (status < 0) {
dev_dbg(&udev->dev, "can't resume, status %d\n", status);
hub_port_logical_disconnect(hub, port1);
+ if (hub_port_power_cycle_required(hub, port1, portstatus)) {
+ dev_dbg(&udev->dev, "device in disabled state, attempt power cycle\n");
+ hub_port_power_cycle(hub, port1);
+ }
} else {
/* Try to enable USB2 hardware LPM */
usb_enable_usb2_hardware_lpm(udev);
--
2.17.1
^ permalink raw reply related [flat|nested] 6+ messages in thread* Re: [PATCH v2 2/2] USB: core: Attempt power cycle port when it's in eSS.Disabled state
2019-11-29 17:41 ` [PATCH v2 2/2] USB: core: Attempt power cycle port when it's in eSS.Disabled state Kai-Heng Feng
@ 2019-12-11 13:45 ` Kai-Heng Feng
2019-12-11 15:08 ` Alan Stern
0 siblings, 1 reply; 6+ messages in thread
From: Kai-Heng Feng @ 2019-12-11 13:45 UTC (permalink / raw)
To: Greg KH; +Cc: stern, linux-usb, linux-kernel
> On Nov 30, 2019, at 01:41, Kai-Heng Feng <kai.heng.feng@canonical.com> wrote:
>
> On Dell TB16, Realtek USB ethernet (r8152) connects to an SMSC hub which
> then connects to ASMedia xHCI's root hub:
>
> /: Bus 04.Port 1: Dev 1, Class=root_hub, Driver=xhci_hcd/2p, 5000M
> |__ Port 1: Dev 2, If 0, Class=Hub, Driver=hub/7p, 5000M
> |__ Port 2: Dev 3, If 0, Class=Vendor Specific Class, Driver=r8152, 5000M
>
> Bus 004 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
> Bus 004 Device 002: ID 0424:5537 Standard Microsystems Corp. USB5537B
> Bus 004 Device 003: ID 0bda:8153 Realtek Semiconductor Corp. RTL8153 Gigabit Ethernet Adapter
>
> The SMSC hub may disconnect after system resume from suspend. When this
> happens, the reset resume attempt fails, and the last resort to disable
> the port and see something comes up later, also fails.
>
> When the issue occurs, the link state stays in eSS.Disabled state
> despite the warm reset attempts. Accoding to spec this can be caused by
> invalid VBus, after some expiremets, the SMSC hub can be brought back
> after a powercycle.
>
> So let's power cycle the port at the end of reset resume attempt, if
> it's in eSS.Disabled state.
If there's no objection, can this fix be reviewed and merged?
Kai-Heng
>
> Signed-off-by: Kai-Heng Feng <kai.heng.feng@canonical.com>
> ---
> v2:
> - Lower dev_info() to dev_dbg().
>
> drivers/usb/core/hub.c | 16 ++++++++++++++++
> 1 file changed, 16 insertions(+)
>
> diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c
> index 6b6cd76ac5e6..a2e6001046f5 100644
> --- a/drivers/usb/core/hub.c
> +++ b/drivers/usb/core/hub.c
> @@ -2739,6 +2739,18 @@ static bool hub_port_warm_reset_required(struct usb_hub *hub, int port1,
> || link_state == USB_SS_PORT_LS_COMP_MOD;
> }
>
> +static bool hub_port_power_cycle_required(struct usb_hub *hub, int port1,
> + u16 portstatus)
> +{
> + u16 link_state;
> +
> + if (!hub_is_superspeed(hub->hdev))
> + return false;
> +
> + link_state = portstatus & USB_PORT_STAT_LINK_STATE;
> + return link_state == USB_SS_PORT_LS_SS_DISABLED;
> +}
> +
> static void hub_port_power_cycle(struct usb_hub *hub, int port1)
> {
> struct usb_port *port_dev = hub->ports[port1 - 1];
> @@ -3601,6 +3613,10 @@ int usb_port_resume(struct usb_device *udev, pm_message_t msg)
> if (status < 0) {
> dev_dbg(&udev->dev, "can't resume, status %d\n", status);
> hub_port_logical_disconnect(hub, port1);
> + if (hub_port_power_cycle_required(hub, port1, portstatus)) {
> + dev_dbg(&udev->dev, "device in disabled state, attempt power cycle\n");
> + hub_port_power_cycle(hub, port1);
> + }
> } else {
> /* Try to enable USB2 hardware LPM */
> usb_enable_usb2_hardware_lpm(udev);
> --
> 2.17.1
>
^ permalink raw reply [flat|nested] 6+ messages in thread* Re: [PATCH v2 2/2] USB: core: Attempt power cycle port when it's in eSS.Disabled state
2019-12-11 13:45 ` Kai-Heng Feng
@ 2019-12-11 15:08 ` Alan Stern
2019-12-17 11:16 ` Mathias Nyman
0 siblings, 1 reply; 6+ messages in thread
From: Alan Stern @ 2019-12-11 15:08 UTC (permalink / raw)
To: Kai-Heng Feng, Mathias Nyman; +Cc: Greg KH, USB list, Kernel development list
On Wed, 11 Dec 2019, Kai-Heng Feng wrote:
>
>
> > On Nov 30, 2019, at 01:41, Kai-Heng Feng <kai.heng.feng@canonical.com> wrote:
> >
> > On Dell TB16, Realtek USB ethernet (r8152) connects to an SMSC hub which
> > then connects to ASMedia xHCI's root hub:
> >
> > /: Bus 04.Port 1: Dev 1, Class=root_hub, Driver=xhci_hcd/2p, 5000M
> > |__ Port 1: Dev 2, If 0, Class=Hub, Driver=hub/7p, 5000M
> > |__ Port 2: Dev 3, If 0, Class=Vendor Specific Class, Driver=r8152, 5000M
> >
> > Bus 004 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
> > Bus 004 Device 002: ID 0424:5537 Standard Microsystems Corp. USB5537B
> > Bus 004 Device 003: ID 0bda:8153 Realtek Semiconductor Corp. RTL8153 Gigabit Ethernet Adapter
> >
> > The SMSC hub may disconnect after system resume from suspend. When this
> > happens, the reset resume attempt fails, and the last resort to disable
> > the port and see something comes up later, also fails.
> >
> > When the issue occurs, the link state stays in eSS.Disabled state
> > despite the warm reset attempts. Accoding to spec this can be caused by
> > invalid VBus, after some expiremets, the SMSC hub can be brought back
> > after a powercycle.
> >
> > So let's power cycle the port at the end of reset resume attempt, if
> > it's in eSS.Disabled state.
>
> If there's no objection, can this fix be reviewed and merged?
>
> Kai-Heng
The patch is okay as far as I'm concerned, since it doesn't do anything
for non-SuperSpeed connections. It should be reviewed by Mathias.
Alan Stern
> >
> > Signed-off-by: Kai-Heng Feng <kai.heng.feng@canonical.com>
> > ---
> > v2:
> > - Lower dev_info() to dev_dbg().
> >
> > drivers/usb/core/hub.c | 16 ++++++++++++++++
> > 1 file changed, 16 insertions(+)
> >
> > diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c
> > index 6b6cd76ac5e6..a2e6001046f5 100644
> > --- a/drivers/usb/core/hub.c
> > +++ b/drivers/usb/core/hub.c
> > @@ -2739,6 +2739,18 @@ static bool hub_port_warm_reset_required(struct usb_hub *hub, int port1,
> > || link_state == USB_SS_PORT_LS_COMP_MOD;
> > }
> >
> > +static bool hub_port_power_cycle_required(struct usb_hub *hub, int port1,
> > + u16 portstatus)
> > +{
> > + u16 link_state;
> > +
> > + if (!hub_is_superspeed(hub->hdev))
> > + return false;
> > +
> > + link_state = portstatus & USB_PORT_STAT_LINK_STATE;
> > + return link_state == USB_SS_PORT_LS_SS_DISABLED;
> > +}
> > +
> > static void hub_port_power_cycle(struct usb_hub *hub, int port1)
> > {
> > struct usb_port *port_dev = hub->ports[port1 - 1];
> > @@ -3601,6 +3613,10 @@ int usb_port_resume(struct usb_device *udev, pm_message_t msg)
> > if (status < 0) {
> > dev_dbg(&udev->dev, "can't resume, status %d\n", status);
> > hub_port_logical_disconnect(hub, port1);
> > + if (hub_port_power_cycle_required(hub, port1, portstatus)) {
> > + dev_dbg(&udev->dev, "device in disabled state, attempt power cycle\n");
> > + hub_port_power_cycle(hub, port1);
> > + }
> > } else {
> > /* Try to enable USB2 hardware LPM */
> > usb_enable_usb2_hardware_lpm(udev);
> > --
> > 2.17.1
^ permalink raw reply [flat|nested] 6+ messages in thread* Re: [PATCH v2 2/2] USB: core: Attempt power cycle port when it's in eSS.Disabled state
2019-12-11 15:08 ` Alan Stern
@ 2019-12-17 11:16 ` Mathias Nyman
2019-12-23 17:32 ` Kai-Heng Feng
0 siblings, 1 reply; 6+ messages in thread
From: Mathias Nyman @ 2019-12-17 11:16 UTC (permalink / raw)
To: Alan Stern, Kai-Heng Feng, Mathias Nyman
Cc: Greg KH, USB list, Kernel development list
On 11.12.2019 17.08, Alan Stern wrote:
> On Wed, 11 Dec 2019, Kai-Heng Feng wrote:
>
>>
>>
>>> On Nov 30, 2019, at 01:41, Kai-Heng Feng <kai.heng.feng@canonical.com> wrote:
>>>
>>> On Dell TB16, Realtek USB ethernet (r8152) connects to an SMSC hub which
>>> then connects to ASMedia xHCI's root hub:
>>>
>>> /: Bus 04.Port 1: Dev 1, Class=root_hub, Driver=xhci_hcd/2p, 5000M
>>> |__ Port 1: Dev 2, If 0, Class=Hub, Driver=hub/7p, 5000M
>>> |__ Port 2: Dev 3, If 0, Class=Vendor Specific Class, Driver=r8152, 5000M
>>>
>>> Bus 004 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
>>> Bus 004 Device 002: ID 0424:5537 Standard Microsystems Corp. USB5537B
>>> Bus 004 Device 003: ID 0bda:8153 Realtek Semiconductor Corp. RTL8153 Gigabit Ethernet Adapter
>>>
>>> The SMSC hub may disconnect after system resume from suspend. When this
>>> happens, the reset resume attempt fails, and the last resort to disable
>>> the port and see something comes up later, also fails.
>>>
>>> When the issue occurs, the link state stays in eSS.Disabled state
>>> despite the warm reset attempts. Accoding to spec this can be caused by
>>> invalid VBus, after some expiremets, the SMSC hub can be brought back
>>> after a powercycle.
Could you open up a bit more how this happens, mainly codepaths how the
USB3 port ends up in eSS.Disabled state
There might be something else wrong here.
My impression is that port should only end up in eSS.Disabled when directed
to with a Set_Port_Feature(PORT_LINK_STATE, eSS.Disabled) Request.
After this we shouldn't attempt warm resets, they won't work for USB3 ports in
ss.Disabled state.
-Mathias
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH v2 2/2] USB: core: Attempt power cycle port when it's in eSS.Disabled state
2019-12-17 11:16 ` Mathias Nyman
@ 2019-12-23 17:32 ` Kai-Heng Feng
0 siblings, 0 replies; 6+ messages in thread
From: Kai-Heng Feng @ 2019-12-23 17:32 UTC (permalink / raw)
To: Mathias Nyman
Cc: Alan Stern, Mathias Nyman, Greg KH, USB list, Kernel development list
> On Dec 17, 2019, at 19:16, Mathias Nyman <mathias.nyman@linux.intel.com> wrote:
>
> On 11.12.2019 17.08, Alan Stern wrote:
>> On Wed, 11 Dec 2019, Kai-Heng Feng wrote:
>>>
>>>
>>>> On Nov 30, 2019, at 01:41, Kai-Heng Feng <kai.heng.feng@canonical.com> wrote:
>>>>
>>>> On Dell TB16, Realtek USB ethernet (r8152) connects to an SMSC hub which
>>>> then connects to ASMedia xHCI's root hub:
>>>>
>>>> /: Bus 04.Port 1: Dev 1, Class=root_hub, Driver=xhci_hcd/2p, 5000M
>>>> |__ Port 1: Dev 2, If 0, Class=Hub, Driver=hub/7p, 5000M
>>>> |__ Port 2: Dev 3, If 0, Class=Vendor Specific Class, Driver=r8152, 5000M
>>>>
>>>> Bus 004 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
>>>> Bus 004 Device 002: ID 0424:5537 Standard Microsystems Corp. USB5537B
>>>> Bus 004 Device 003: ID 0bda:8153 Realtek Semiconductor Corp. RTL8153 Gigabit Ethernet Adapter
>>>>
>>>> The SMSC hub may disconnect after system resume from suspend. When this
>>>> happens, the reset resume attempt fails, and the last resort to disable
>>>> the port and see something comes up later, also fails.
>>>>
>>>> When the issue occurs, the link state stays in eSS.Disabled state
>>>> despite the warm reset attempts. Accoding to spec this can be caused by
>>>> invalid VBus, after some expiremets, the SMSC hub can be brought back
>>>> after a powercycle.
>
> Could you open up a bit more how this happens, mainly codepaths how the
> USB3 port ends up in eSS.Disabled state
It happens right after hub_resume(), the first get_port_status():
Dec 23 09:46:58 u-XPS-13-9370 kernel: usb usb4: usb resume
Dec 23 09:46:58 u-XPS-13-9370 kernel: hub 4-0:1.0: hub_resume
Dec 23 09:46:58 u-XPS-13-9370 kernel: xhci_hcd 0000:3f:00.0: Get port status 4-1 read: 0x280, return 0x280
Dec 23 09:46:58 u-XPS-13-9370 kernel: usb usb4-port1: status 0280 change 0000
Dec 23 09:46:58 u-XPS-13-9370 kernel: xhci_hcd 0000:3f:00.0: Get port status 4-2 read: 0x2a0, return 0x2a0
Dec 23 09:46:58 u-XPS-13-9370 kernel: xhci_hcd 0000:3f:00.0: Get port status 4-1 read: 0x280, return 0x280
Dec 23 09:46:58 u-XPS-13-9370 kernel: xhci_hcd 0000:3f:00.0: Get port status 4-1 read: 0x280, return 0x280
Dec 23 09:46:58 u-XPS-13-9370 kernel: xhci_hcd 0000:3f:00.0: Get port status 4-1 read: 0x280, return 0x280
And it keeps getting 0x280. It should mean PP = 1 and PLS = 4, so it's in Disabled state.
>
> There might be something else wrong here.
> My impression is that port should only end up in eSS.Disabled when directed
> to with a Set_Port_Feature(PORT_LINK_STATE, eSS.Disabled) Request.
> After this we shouldn't attempt warm resets, they won't work for USB3 ports in
> ss.Disabled state.
Do you suggest that we should power cycle the port in xHCI instead of USB core?
Kai-Heng
>
> -Mathias
^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2019-12-23 17:32 UTC | newest]
Thread overview: 6+ messages (download: mbox.gz / follow: Atom feed)
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2019-11-29 17:41 [PATCH v2 1/2] USB: core: Make port power cycle a seperate helper function Kai-Heng Feng
2019-11-29 17:41 ` [PATCH v2 2/2] USB: core: Attempt power cycle port when it's in eSS.Disabled state Kai-Heng Feng
2019-12-11 13:45 ` Kai-Heng Feng
2019-12-11 15:08 ` Alan Stern
2019-12-17 11:16 ` Mathias Nyman
2019-12-23 17:32 ` Kai-Heng Feng
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