Commit a8089250 authored by Hongyu Xie's avatar Hongyu Xie Committed by Greg Kroah-Hartman
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xhci: Keep interrupt disabled in initialization until host is running. 



irq is disabled in xhci_quiesce(called by xhci_halt, with bit:2 cleared
in USBCMD register), but xhci_run(called by usb_add_hcd) re-enable it.
It's possible that you will receive thousands of interrupt requests
after initialization for 2.0 roothub. And you will get a lot of
warning like, "xHCI dying, ignoring interrupt. Shouldn't IRQs be
disabled?". This amount of interrupt requests will cause the entire
system to freeze.
This problem was first found on a device with ASM2142 host controller
on it.

[tidy up old code while moving it, reword header -Mathias]

Cc: stable@kernel.org
Signed-off-by: default avatarHongyu Xie <xiehongyu1@kylinos.cn>
Signed-off-by: default avatarMathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20220623111945.1557702-2-mathias.nyman@linux.intel.com


Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 2bdc2bcd

drivers/usb/host/xhci.c

+22 −13
Original line number Diff line number Diff line
@@ -611,15 +611,37 @@ static int xhci_init(struct usb_hcd *hcd) 


static int xhci_run_finished(struct xhci_hcd *xhci)

{

	unsigned long	flags;

	u32		temp;



	/*

	 * Enable interrupts before starting the host (xhci 4.2 and 5.5.2).

	 * Protect the short window before host is running with a lock

	 */

	spin_lock_irqsave(&xhci->lock, flags);



	xhci_dbg_trace(xhci, trace_xhci_dbg_init, "Enable interrupts");

	temp = readl(&xhci->op_regs->command);

	temp |= (CMD_EIE);

	writel(temp, &xhci->op_regs->command);



	xhci_dbg_trace(xhci, trace_xhci_dbg_init, "Enable primary interrupter");

	temp = readl(&xhci->ir_set->irq_pending);

	writel(ER_IRQ_ENABLE(temp), &xhci->ir_set->irq_pending);



	if (xhci_start(xhci)) {

		xhci_halt(xhci);

		spin_unlock_irqrestore(&xhci->lock, flags);

		return -ENODEV;

	}



	xhci->cmd_ring_state = CMD_RING_STATE_RUNNING;



	if (xhci->quirks & XHCI_NEC_HOST)

		xhci_ring_cmd_db(xhci);



	spin_unlock_irqrestore(&xhci->lock, flags);



	return 0;

}
@@ -668,19 +690,6 @@ int xhci_run(struct usb_hcd *hcd) 
	temp |= (xhci->imod_interval / 250) & ER_IRQ_INTERVAL_MASK;

	writel(temp, &xhci->ir_set->irq_control);



	/* Set the HCD state before we enable the irqs */

	temp = readl(&xhci->op_regs->command);

	temp |= (CMD_EIE);

	xhci_dbg_trace(xhci, trace_xhci_dbg_init,

			"// Enable interrupts, cmd = 0x%x.", temp);

	writel(temp, &xhci->op_regs->command);



	temp = readl(&xhci->ir_set->irq_pending);

	xhci_dbg_trace(xhci, trace_xhci_dbg_init,

			"// Enabling event ring interrupter %p by writing 0x%x to irq_pending",

			xhci->ir_set, (unsigned int) ER_IRQ_ENABLE(temp));

	writel(ER_IRQ_ENABLE(temp), &xhci->ir_set->irq_pending);



	if (xhci->quirks & XHCI_NEC_HOST) {

		struct xhci_command *command;