From 958c0bd86075d4ef1c936998deefe1947e539240 Mon Sep 17 00:00:00 2001 From: Aaron Ma Date: Fri, 9 Nov 2018 17:21:20 +0200 Subject: usb: xhci: fix uninitialized completion when USB3 port got wrong status Realtek USB3.0 Card Reader [0bda:0328] reports wrong port status on Cannon lake PCH USB3.1 xHCI [8086:a36d] after resume from S3, after clear port reset it works fine. Since this device is registered on USB3 roothub at boot, when port status reports not superspeed, xhci_get_port_status will call an uninitialized completion in bus_state[0]. Kernel will hang because of NULL pointer. Restrict the USB2 resume status check in USB2 roothub to fix hang issue. Cc: stable@vger.kernel.org Signed-off-by: Aaron Ma Signed-off-by: Mathias Nyman Signed-off-by: Greg Kroah-Hartman --- drivers/usb/host/xhci-hub.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers/usb/host/xhci-hub.c') diff --git a/drivers/usb/host/xhci-hub.c b/drivers/usb/host/xhci-hub.c index 12eea73d9f20..60e4ac7ae4f8 100644 --- a/drivers/usb/host/xhci-hub.c +++ b/drivers/usb/host/xhci-hub.c @@ -876,7 +876,7 @@ static u32 xhci_get_port_status(struct usb_hcd *hcd, status |= USB_PORT_STAT_SUSPEND; } if ((raw_port_status & PORT_PLS_MASK) == XDEV_RESUME && - !DEV_SUPERSPEED_ANY(raw_port_status)) { + !DEV_SUPERSPEED_ANY(raw_port_status) && hcd->speed < HCD_USB3) { if ((raw_port_status & PORT_RESET) || !(raw_port_status & PORT_PE)) return 0xffffffff; -- cgit From a5baeaeabcca3244782a9b6382ebab6f8a58f583 Mon Sep 17 00:00:00 2001 From: Aaron Ma Date: Fri, 9 Nov 2018 17:21:21 +0200 Subject: usb: xhci: fix timeout for transition from RExit to U0 This definition is used by msecs_to_jiffies in milliseconds. According to the comments, max rexit timeout should be 20ms. Align with the comments to properly calculate the delay. Verified on Sunrise Point-LP and Cannon Lake. Cc: stable@vger.kernel.org Signed-off-by: Aaron Ma Signed-off-by: Mathias Nyman Signed-off-by: Greg Kroah-Hartman --- drivers/usb/host/xhci-hub.c | 4 ++-- drivers/usb/host/xhci.h | 2 +- 2 files changed, 3 insertions(+), 3 deletions(-) (limited to 'drivers/usb/host/xhci-hub.c') diff --git a/drivers/usb/host/xhci-hub.c b/drivers/usb/host/xhci-hub.c index 60e4ac7ae4f8..da98a11244e2 100644 --- a/drivers/usb/host/xhci-hub.c +++ b/drivers/usb/host/xhci-hub.c @@ -921,7 +921,7 @@ static u32 xhci_get_port_status(struct usb_hcd *hcd, time_left = wait_for_completion_timeout( &bus_state->rexit_done[wIndex], msecs_to_jiffies( - XHCI_MAX_REXIT_TIMEOUT)); + XHCI_MAX_REXIT_TIMEOUT_MS)); spin_lock_irqsave(&xhci->lock, flags); if (time_left) { @@ -935,7 +935,7 @@ static u32 xhci_get_port_status(struct usb_hcd *hcd, } else { int port_status = readl(port->addr); xhci_warn(xhci, "Port resume took longer than %i msec, port status = 0x%x\n", - XHCI_MAX_REXIT_TIMEOUT, + XHCI_MAX_REXIT_TIMEOUT_MS, port_status); status |= USB_PORT_STAT_SUSPEND; clear_bit(wIndex, &bus_state->rexit_ports); diff --git a/drivers/usb/host/xhci.h b/drivers/usb/host/xhci.h index bf0b3692dc9a..5f0c4f197f13 100644 --- a/drivers/usb/host/xhci.h +++ b/drivers/usb/host/xhci.h @@ -1680,7 +1680,7 @@ struct xhci_bus_state { * It can take up to 20 ms to transition from RExit to U0 on the * Intel Lynx Point LP xHCI host. */ -#define XHCI_MAX_REXIT_TIMEOUT (20 * 1000) +#define XHCI_MAX_REXIT_TIMEOUT_MS 20 static inline unsigned int hcd_index(struct usb_hcd *hcd) { -- cgit From 2f31a67f01a8beb22cae754c53522cb61a005750 Mon Sep 17 00:00:00 2001 From: Mathias Nyman Date: Thu, 15 Nov 2018 11:38:41 +0200 Subject: usb: xhci: Prevent bus suspend if a port connect change or polling state is detected USB3 roothub might autosuspend before a plugged USB3 device is detected, causing USB3 device enumeration failure. USB3 devices don't show up as connected and enabled until USB3 link trainig completes. On a fast booting platform with a slow USB3 link training the link might reach the connected enabled state just as the bus is suspending. If this device is discovered first time by the xhci_bus_suspend() routine it will be put to U3 suspended state like the other ports which failed to suspend earlier. The hub thread will notice the connect change and resume the bus, moving the port back to U0 This U0 -> U3 -> U0 transition right after being connected seems to be too much for some devices, causing them to first go to SS.Inactive state, and finally end up stuck in a polling state with reset asserted Fix this by failing the bus suspend if a port has a connect change or is in a polling state in xhci_bus_suspend(). Don't do any port changes until all ports are checked, buffer all port changes and only write them in the end if suspend can proceed Cc: stable@vger.kernel.org Signed-off-by: Mathias Nyman Signed-off-by: Greg Kroah-Hartman --- drivers/usb/host/xhci-hub.c | 60 ++++++++++++++++++++++++++++++++++----------- 1 file changed, 46 insertions(+), 14 deletions(-) (limited to 'drivers/usb/host/xhci-hub.c') diff --git a/drivers/usb/host/xhci-hub.c b/drivers/usb/host/xhci-hub.c index da98a11244e2..94aca1b5ac8a 100644 --- a/drivers/usb/host/xhci-hub.c +++ b/drivers/usb/host/xhci-hub.c @@ -1474,15 +1474,18 @@ int xhci_bus_suspend(struct usb_hcd *hcd) unsigned long flags; struct xhci_hub *rhub; struct xhci_port **ports; + u32 portsc_buf[USB_MAXCHILDREN]; + bool wake_enabled; rhub = xhci_get_rhub(hcd); ports = rhub->ports; max_ports = rhub->num_ports; bus_state = &xhci->bus_state[hcd_index(hcd)]; + wake_enabled = hcd->self.root_hub->do_remote_wakeup; spin_lock_irqsave(&xhci->lock, flags); - if (hcd->self.root_hub->do_remote_wakeup) { + if (wake_enabled) { if (bus_state->resuming_ports || /* USB2 */ bus_state->port_remote_wakeup) { /* USB3 */ spin_unlock_irqrestore(&xhci->lock, flags); @@ -1490,26 +1493,36 @@ int xhci_bus_suspend(struct usb_hcd *hcd) return -EBUSY; } } - - port_index = max_ports; + /* + * Prepare ports for suspend, but don't write anything before all ports + * are checked and we know bus suspend can proceed + */ bus_state->bus_suspended = 0; + port_index = max_ports; while (port_index--) { - /* suspend the port if the port is not suspended */ u32 t1, t2; - int slot_id; t1 = readl(ports[port_index]->addr); t2 = xhci_port_state_to_neutral(t1); + portsc_buf[port_index] = 0; - if ((t1 & PORT_PE) && !(t1 & PORT_PLS_MASK)) { - xhci_dbg(xhci, "port %d not suspended\n", port_index); - slot_id = xhci_find_slot_id_by_port(hcd, xhci, - port_index + 1); - if (slot_id) { + /* Bail out if a USB3 port has a new device in link training */ + if ((t1 & PORT_PLS_MASK) == XDEV_POLLING) { + bus_state->bus_suspended = 0; + spin_unlock_irqrestore(&xhci->lock, flags); + xhci_dbg(xhci, "Bus suspend bailout, port in polling\n"); + return -EBUSY; + } + + /* suspend ports in U0, or bail out for new connect changes */ + if ((t1 & PORT_PE) && (t1 & PORT_PLS_MASK) == XDEV_U0) { + if ((t1 & PORT_CSC) && wake_enabled) { + bus_state->bus_suspended = 0; spin_unlock_irqrestore(&xhci->lock, flags); - xhci_stop_device(xhci, slot_id, 1); - spin_lock_irqsave(&xhci->lock, flags); + xhci_dbg(xhci, "Bus suspend bailout, port connect change\n"); + return -EBUSY; } + xhci_dbg(xhci, "port %d not suspended\n", port_index); t2 &= ~PORT_PLS_MASK; t2 |= PORT_LINK_STROBE | XDEV_U3; set_bit(port_index, &bus_state->bus_suspended); @@ -1518,7 +1531,7 @@ int xhci_bus_suspend(struct usb_hcd *hcd) * including the USB 3.0 roothub, but only if CONFIG_PM * is enabled, so also enable remote wake here. */ - if (hcd->self.root_hub->do_remote_wakeup) { + if (wake_enabled) { if (t1 & PORT_CONNECT) { t2 |= PORT_WKOC_E | PORT_WKDISC_E; t2 &= ~PORT_WKCONN_E; @@ -1538,7 +1551,26 @@ int xhci_bus_suspend(struct usb_hcd *hcd) t1 = xhci_port_state_to_neutral(t1); if (t1 != t2) - writel(t2, ports[port_index]->addr); + portsc_buf[port_index] = t2; + } + + /* write port settings, stopping and suspending ports if needed */ + port_index = max_ports; + while (port_index--) { + if (!portsc_buf[port_index]) + continue; + if (test_bit(port_index, &bus_state->bus_suspended)) { + int slot_id; + + slot_id = xhci_find_slot_id_by_port(hcd, xhci, + port_index + 1); + if (slot_id) { + spin_unlock_irqrestore(&xhci->lock, flags); + xhci_stop_device(xhci, slot_id, 1); + spin_lock_irqsave(&xhci->lock, flags); + } + } + writel(portsc_buf[port_index], ports[port_index]->addr); } hcd->state = HC_STATE_SUSPENDED; bus_state->next_statechange = jiffies + msecs_to_jiffies(10); -- cgit