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: Hongyu Xie <xiehongyu1@kylinos.cn>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20220623111945.1557702-2-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Hongyu Xie 2022-06-23 14:19:42 +03:00 committed by Greg Kroah-Hartman
parent 2bdc2bcd9a
commit a808925075

View File

@ -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;