FAILED: patch "[PATCH] xhci: track port suspend state correctly in unsuccessful" failed to apply to 5.4-stable tree

FAILED: patch "[PATCH] xhci: track port suspend state correctly in unsuccessful" failed to apply to 5.4-stable tree

[gregkh]

The patch below does not apply to the 5.4-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@vger.kernel.org>.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.4.y
git checkout FETCH_HEAD
git cherry-pick -x d7cdfc319b2bcf6899ab0a05eec0958bc802a9a1
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable@vger.kernel.org>' --in-reply-to '2023101517-portside-swapping-ca7a@gregkh' --subject-prefix 'PATCH 5.4.y' HEAD^..

Possible dependencies:



thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From d7cdfc319b2bcf6899ab0a05eec0958bc802a9a1 Mon Sep 17 00:00:00 2001
From: Mathias Nyman <mathias.nyman@linux.intel.com>
Date: Fri, 15 Sep 2023 17:31:06 +0300
Subject: [PATCH] xhci: track port suspend state correctly in unsuccessful
 resume cases

xhci-hub.c tracks suspended ports in a suspended_port bitfield.
This is checked when responding to a Get_Status(PORT) request to see if a
port in running U0 state was recently resumed, and adds the required
USB_PORT_STAT_C_SUSPEND change bit in those cases.

The suspended_port bit was left uncleared if a device is disconnected
during suspend. The bit remained set even when a new device was connected
and enumerated. The set bit resulted in a incorrect Get_Status(PORT)
response with a bogus USB_PORT_STAT_C_SUSPEND change
bit set once the new device reached U0 link state.

USB_PORT_STAT_C_SUSPEND change bit is only used for USB2 ports, but
xhci-hub keeps track of both USB2 and USB3 suspended ports.

Cc: stable@vger.kernel.org
Reported-by: Wesley Cheng <quic_wcheng@quicinc.com>
Closes: https://lore.kernel.org/linux-usb/d68aa806-b26a-0e43-42fb-b8067325e967@quicinc.com/
Fixes: 1d5810b6923c ("xhci: Rework port suspend structures for limited ports.")
Tested-by: Wesley Cheng <quic_wcheng@quicinc.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20230915143108.1532163-3-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/usb/host/xhci-hub.c b/drivers/usb/host/xhci-hub.c
index 0054d02239e2..0df5d807a77e 100644
--- a/drivers/usb/host/xhci-hub.c
+++ b/drivers/usb/host/xhci-hub.c
@@ -1062,19 +1062,19 @@ static void xhci_get_usb3_port_status(struct xhci_port *port, u32 *status,
 		*status |= USB_PORT_STAT_C_CONFIG_ERROR << 16;
 
 	/* USB3 specific wPortStatus bits */
-	if (portsc & PORT_POWER) {
+	if (portsc & PORT_POWER)
 		*status |= USB_SS_PORT_STAT_POWER;
-		/* link state handling */
-		if (link_state == XDEV_U0)
-			bus_state->suspended_ports &= ~(1 << portnum);
-	}
 
-	/* remote wake resume signaling complete */
-	if (bus_state->port_remote_wakeup & (1 << portnum) &&
+	/* no longer suspended or resuming */
+	if (link_state != XDEV_U3 &&
 	    link_state != XDEV_RESUME &&
 	    link_state != XDEV_RECOVERY) {
-		bus_state->port_remote_wakeup &= ~(1 << portnum);
-		usb_hcd_end_port_resume(&hcd->self, portnum);
+		/* remote wake resume signaling complete */
+		if (bus_state->port_remote_wakeup & (1 << portnum)) {
+			bus_state->port_remote_wakeup &= ~(1 << portnum);
+			usb_hcd_end_port_resume(&hcd->self, portnum);
+		}
+		bus_state->suspended_ports &= ~(1 << portnum);
 	}
 
 	xhci_hub_report_usb3_link_state(xhci, status, portsc);
@@ -1131,6 +1131,7 @@ static void xhci_get_usb2_port_status(struct xhci_port *port, u32 *status,
 			usb_hcd_end_port_resume(&port->rhub->hcd->self, portnum);
 		}
 		port->rexit_active = 0;
+		bus_state->suspended_ports &= ~(1 << portnum);
 	}
 }