From 6e4468b9a0793dfb53eb80d9fe52c739b13b27fd Mon Sep 17 00:00:00 2001 From: Elric Fu Date: Wed, 27 Jun 2012 16:31:52 +0800 Subject: [PATCH] xHCI: cancel command after command timeout The patch is used to cancel command when the command isn't acknowledged and a timeout occurs. This patch should be backported to kernels as old as 3.0, that contain the commit 7ed603ecf8b68ab81f4c83097d3063d43ec73bb8 "xhci: Add an assertion to check for virt_dev=0 bug." That commit papers over a NULL pointer dereference, and this patch fixes the underlying issue that caused the NULL pointer dereference. Signed-off-by: Elric Fu Signed-off-by: Sarah Sharp Tested-by: Miroslav Sabljic Cc: stable@vger.kernel.org --- drivers/usb/host/xhci.c | 26 +++++++++++++++++++------- drivers/usb/host/xhci.h | 3 +++ 2 files changed, 22 insertions(+), 7 deletions(-) diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c index 3f0763d63598..b95e3e8a293e 100644 --- a/drivers/usb/host/xhci.c +++ b/drivers/usb/host/xhci.c @@ -2402,6 +2402,7 @@ static int xhci_configure_endpoint(struct xhci_hcd *xhci, struct completion *cmd_completion; u32 *cmd_status; struct xhci_virt_device *virt_dev; + union xhci_trb *cmd_trb; spin_lock_irqsave(&xhci->lock, flags); virt_dev = xhci->devs[udev->slot_id]; @@ -2447,6 +2448,7 @@ static int xhci_configure_endpoint(struct xhci_hcd *xhci, } init_completion(cmd_completion); + cmd_trb = xhci->cmd_ring->dequeue; if (!ctx_change) ret = xhci_queue_configure_endpoint(xhci, in_ctx->dma, udev->slot_id, must_succeed); @@ -2468,14 +2470,17 @@ static int xhci_configure_endpoint(struct xhci_hcd *xhci, /* Wait for the configure endpoint command to complete */ timeleft = wait_for_completion_interruptible_timeout( cmd_completion, - USB_CTRL_SET_TIMEOUT); + XHCI_CMD_DEFAULT_TIMEOUT); if (timeleft <= 0) { xhci_warn(xhci, "%s while waiting for %s command\n", timeleft == 0 ? "Timeout" : "Signal", ctx_change == 0 ? "configure endpoint" : "evaluate context"); - /* FIXME cancel the configure endpoint command */ + /* cancel the configure endpoint command */ + ret = xhci_cancel_cmd(xhci, command, cmd_trb); + if (ret < 0) + return ret; return -ETIME; } @@ -3424,8 +3429,10 @@ int xhci_alloc_dev(struct usb_hcd *hcd, struct usb_device *udev) unsigned long flags; int timeleft; int ret; + union xhci_trb *cmd_trb; spin_lock_irqsave(&xhci->lock, flags); + cmd_trb = xhci->cmd_ring->dequeue; ret = xhci_queue_slot_control(xhci, TRB_ENABLE_SLOT, 0); if (ret) { spin_unlock_irqrestore(&xhci->lock, flags); @@ -3437,12 +3444,12 @@ int xhci_alloc_dev(struct usb_hcd *hcd, struct usb_device *udev) /* XXX: how much time for xHC slot assignment? */ timeleft = wait_for_completion_interruptible_timeout(&xhci->addr_dev, - USB_CTRL_SET_TIMEOUT); + XHCI_CMD_DEFAULT_TIMEOUT); if (timeleft <= 0) { xhci_warn(xhci, "%s while waiting for a slot\n", timeleft == 0 ? "Timeout" : "Signal"); - /* FIXME cancel the enable slot request */ - return 0; + /* cancel the enable slot request */ + return xhci_cancel_cmd(xhci, NULL, cmd_trb); } if (!xhci->slot_id) { @@ -3503,6 +3510,7 @@ int xhci_address_device(struct usb_hcd *hcd, struct usb_device *udev) struct xhci_slot_ctx *slot_ctx; struct xhci_input_control_ctx *ctrl_ctx; u64 temp_64; + union xhci_trb *cmd_trb; if (!udev->slot_id) { xhci_dbg(xhci, "Bad Slot ID %d\n", udev->slot_id); @@ -3541,6 +3549,7 @@ int xhci_address_device(struct usb_hcd *hcd, struct usb_device *udev) xhci_dbg_ctx(xhci, virt_dev->in_ctx, 2); spin_lock_irqsave(&xhci->lock, flags); + cmd_trb = xhci->cmd_ring->dequeue; ret = xhci_queue_address_device(xhci, virt_dev->in_ctx->dma, udev->slot_id); if (ret) { @@ -3553,7 +3562,7 @@ int xhci_address_device(struct usb_hcd *hcd, struct usb_device *udev) /* ctrl tx can take up to 5 sec; XXX: need more time for xHC? */ timeleft = wait_for_completion_interruptible_timeout(&xhci->addr_dev, - USB_CTRL_SET_TIMEOUT); + XHCI_CMD_DEFAULT_TIMEOUT); /* FIXME: From section 4.3.4: "Software shall be responsible for timing * the SetAddress() "recovery interval" required by USB and aborting the * command on a timeout. @@ -3561,7 +3570,10 @@ int xhci_address_device(struct usb_hcd *hcd, struct usb_device *udev) if (timeleft <= 0) { xhci_warn(xhci, "%s while waiting for address device command\n", timeleft == 0 ? "Timeout" : "Signal"); - /* FIXME cancel the address device command */ + /* cancel the address device command */ + ret = xhci_cancel_cmd(xhci, NULL, cmd_trb); + if (ret < 0) + return ret; return -ETIME; } diff --git a/drivers/usb/host/xhci.h b/drivers/usb/host/xhci.h index fdfcebf342e8..e81ccfa3552f 100644 --- a/drivers/usb/host/xhci.h +++ b/drivers/usb/host/xhci.h @@ -1256,6 +1256,9 @@ struct xhci_td { union xhci_trb *last_trb; }; +/* xHCI command default timeout value */ +#define XHCI_CMD_DEFAULT_TIMEOUT (5 * HZ) + /* command descriptor */ struct xhci_cd { struct list_head cancel_cmd_list; -- 2.39.5