[PATCH AUTOSEL 4.14 05/56] usb: gadget: f_fs: Use stream_open() for endpoint files

[PATCH AUTOSEL 4.14 05/56] usb: gadget: f_fs: Use stream_open() for endpoint files

[Sasha Levin]

From: Pavankumar Kondeti <quic_pkondeti@quicinc.com>

[ Upstream commit c76ef96fc00eb398c8fc836b0eb2f82bcc619dc7 ]

Function fs endpoint file operations are synchronized via an interruptible
mutex wait. However we see threads that do ep file operations concurrently
are getting blocked for the mutex lock in __fdget_pos(). This is an
uninterruptible wait and we see hung task warnings and kernel panic
if hung_task_panic systcl is enabled if host does not send/receive
the data for long time.

The reason for threads getting blocked in __fdget_pos() is due to
the file position protection introduced by the commit 9c225f2655e3
("vfs: atomic f_pos accesses as per POSIX"). Since function fs
endpoint files does not have the notion of the file position, switch
to the stream mode. This will bypass the file position mutex and
threads will be blocked in interruptible state for the function fs
mutex.

It should not affects user space as we are only changing the task state
changes the task state from UNINTERRUPTIBLE to INTERRUPTIBLE while waiting
for the USB transfers to be finished. However there is a slight change to
the O_NONBLOCK behavior. Earlier threads that are using O_NONBLOCK are also
getting blocked inside fdget_pos(). Now they reach to function fs and error
code is returned. The non blocking behavior is actually honoured now.

Reviewed-by: John Keeping <john@metanate.com>
Signed-off-by: Pavankumar Kondeti <quic_pkondeti@quicinc.com>
Link: https://lore.kernel.org/r/1636712682-1226-1-git-send-email-quic_pkondeti@quicinc.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/usb/gadget/function/f_fs.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/usb/gadget/function/f_fs.c b/drivers/usb/gadget/function/f_fs.c
index 6029f9b00b4a0..61795025f11b6 100644
--- a/drivers/usb/gadget/function/f_fs.c
+++ b/drivers/usb/gadget/function/f_fs.c
@@ -608,7 +608,7 @@ static int ffs_ep0_open(struct inode *inode, struct file *file)
 	file->private_data = ffs;
 	ffs_data_opened(ffs);
 
-	return 0;
+	return stream_open(inode, file);
 }
 
 static int ffs_ep0_release(struct inode *inode, struct file *file)
@@ -1072,7 +1072,7 @@ ffs_epfile_open(struct inode *inode, struct file *file)
 	file->private_data = epfile;
 	ffs_data_opened(epfile->ffs);
 
-	return 0;
+	return stream_open(inode, file);
 }
 
 static int ffs_aio_cancel(struct kiocb *kiocb)
-- 
2.34.1

[PATCH AUTOSEL 4.14 22/56] usb: uhci: add aspeed ast2600 uhci support

[Sasha Levin]

From: Neal Liu <neal_liu@aspeedtech.com>

[ Upstream commit 554abfe2eadec97d12c71d4a69da1518478f69eb ]

Enable ast2600 uhci quirks.

Signed-off-by: Neal Liu <neal_liu@aspeedtech.com>
Link: https://lore.kernel.org/r/20211126100021.2331024-1-neal_liu@aspeedtech.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/usb/host/uhci-platform.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/usb/host/uhci-platform.c b/drivers/usb/host/uhci-platform.c
index 6cb16d4b22578..4e91f7b21a796 100644
--- a/drivers/usb/host/uhci-platform.c
+++ b/drivers/usb/host/uhci-platform.c
@@ -113,7 +113,8 @@ static int uhci_hcd_platform_probe(struct platform_device *pdev)
 				num_ports);
 		}
 		if (of_device_is_compatible(np, "aspeed,ast2400-uhci") ||
-		    of_device_is_compatible(np, "aspeed,ast2500-uhci")) {
+		    of_device_is_compatible(np, "aspeed,ast2500-uhci") ||
+		    of_device_is_compatible(np, "aspeed,ast2600-uhci")) {
 			uhci->is_aspeed = 1;
 			dev_info(&pdev->dev,
 				 "Enabled Aspeed implementation workarounds\n");
-- 
2.34.1

[PATCH AUTOSEL 4.14 37/56] usb: hub: Add delay for SuperSpeed hub resume to let links transit to U0

[Sasha Levin]

From: Kai-Heng Feng <kai.heng.feng@canonical.com>

[ Upstream commit 00558586382891540c59c9febc671062425a6e47 ]

When a new USB device gets plugged to nested hubs, the affected hub,
which connects to usb 2-1.4-port2, doesn't report there's any change,
hence the nested hubs go back to runtime suspend like nothing happened:
[  281.032951] usb usb2: usb wakeup-resume
[  281.032959] usb usb2: usb auto-resume
[  281.032974] hub 2-0:1.0: hub_resume
[  281.033011] usb usb2-port1: status 0263 change 0000
[  281.033077] hub 2-0:1.0: state 7 ports 4 chg 0000 evt 0000
[  281.049797] usb 2-1: usb wakeup-resume
[  281.069800] usb 2-1: Waited 0ms for CONNECT
[  281.069810] usb 2-1: finish resume
[  281.070026] hub 2-1:1.0: hub_resume
[  281.070250] usb 2-1-port4: status 0203 change 0000
[  281.070272] usb usb2-port1: resume, status 0
[  281.070282] hub 2-1:1.0: state 7 ports 4 chg 0010 evt 0000
[  281.089813] usb 2-1.4: usb wakeup-resume
[  281.109792] usb 2-1.4: Waited 0ms for CONNECT
[  281.109801] usb 2-1.4: finish resume
[  281.109991] hub 2-1.4:1.0: hub_resume
[  281.110147] usb 2-1.4-port2: status 0263 change 0000
[  281.110234] usb 2-1-port4: resume, status 0
[  281.110239] usb 2-1-port4: status 0203, change 0000, 10.0 Gb/s
[  281.110266] hub 2-1.4:1.0: state 7 ports 4 chg 0000 evt 0000
[  281.110426] hub 2-1.4:1.0: hub_suspend
[  281.110565] usb 2-1.4: usb auto-suspend, wakeup 1
[  281.130998] hub 2-1:1.0: hub_suspend
[  281.137788] usb 2-1: usb auto-suspend, wakeup 1
[  281.142935] hub 2-0:1.0: state 7 ports 4 chg 0000 evt 0000
[  281.177828] usb 2-1: usb wakeup-resume
[  281.197839] usb 2-1: Waited 0ms for CONNECT
[  281.197850] usb 2-1: finish resume
[  281.197984] hub 2-1:1.0: hub_resume
[  281.198203] usb 2-1-port4: status 0203 change 0000
[  281.198228] usb usb2-port1: resume, status 0
[  281.198237] hub 2-1:1.0: state 7 ports 4 chg 0010 evt 0000
[  281.217835] usb 2-1.4: usb wakeup-resume
[  281.237834] usb 2-1.4: Waited 0ms for CONNECT
[  281.237845] usb 2-1.4: finish resume
[  281.237990] hub 2-1.4:1.0: hub_resume
[  281.238067] usb 2-1.4-port2: status 0263 change 0000
[  281.238148] usb 2-1-port4: resume, status 0
[  281.238152] usb 2-1-port4: status 0203, change 0000, 10.0 Gb/s
[  281.238166] hub 2-1.4:1.0: state 7 ports 4 chg 0000 evt 0000
[  281.238385] hub 2-1.4:1.0: hub_suspend
[  281.238523] usb 2-1.4: usb auto-suspend, wakeup 1
[  281.258076] hub 2-1:1.0: hub_suspend
[  281.265744] usb 2-1: usb auto-suspend, wakeup 1
[  281.285976] hub 2-0:1.0: hub_suspend
[  281.285988] usb usb2: bus auto-suspend, wakeup 1

USB 3.2 spec, 9.2.5.4 "Changing Function Suspend State" says that "If
the link is in a non-U0 state, then the device must transition the link
to U0 prior to sending the remote wake message", but the hub only
transits the link to U0 after signaling remote wakeup.

So be more forgiving and use a 20ms delay to let the link transit to U0
for remote wakeup.

Suggested-by: Alan Stern <stern@rowland.harvard.edu>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Kai-Heng Feng <kai.heng.feng@canonical.com>
Link: https://lore.kernel.org/r/20211215120108.336597-1-kai.heng.feng@canonical.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/usb/core/hub.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c
index 56a0bd05aa2c0..86258d3d173d7 100644
--- a/drivers/usb/core/hub.c
+++ b/drivers/usb/core/hub.c
@@ -1077,7 +1077,10 @@ static void hub_activate(struct usb_hub *hub, enum hub_activation_type type)
 		} else {
 			hub_power_on(hub, true);
 		}
-	}
+	/* Give some time on remote wakeup to let links to transit to U0 */
+	} else if (hub_is_superspeed(hub->hdev))
+		msleep(20);
+
  init2:
 
 	/*
-- 
2.34.1