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Content-Language: en-US To: Mathias Nyman , CC: , Hongyu Xie , , Hongyu Xie , "# 5 . 15" References: <20220623111945.1557702-1-mathias.nyman@linux.intel.com> <20220623111945.1557702-2-mathias.nyman@linux.intel.com> From: Prashanth K In-Reply-To: <20220623111945.1557702-2-mathias.nyman@linux.intel.com> Content-Type: text/plain; charset="UTF-8"; format=flowed Content-Transfer-Encoding: 7bit X-Originating-IP: [10.80.80.8] X-ClientProxiedBy: nasanex01a.na.qualcomm.com (10.52.223.231) To nalasex01a.na.qualcomm.com (10.47.209.196) X-QCInternal: smtphost X-Proofpoint-Virus-Version: vendor=nai engine=6200 definitions=5800 signatures=585085 X-Proofpoint-GUID: ThCtHQVabx9N3tQQlffw9qp6i6mF_beo X-Proofpoint-ORIG-GUID: ThCtHQVabx9N3tQQlffw9qp6i6mF_beo X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.267,Aquarius:18.0.957,Hydra:6.0.601,FMLib:17.11.176.26 definitions=2023-09-12_24,2023-09-05_01,2023-05-22_02 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 malwarescore=0 bulkscore=0 mlxscore=0 suspectscore=0 adultscore=0 mlxlogscore=635 priorityscore=1501 impostorscore=0 spamscore=0 clxscore=1011 lowpriorityscore=0 phishscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2308100000 definitions=main-2309130050 Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org On 23-06-22 04:49 pm, Mathias Nyman wrote: > From: Hongyu Xie > > 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 > Signed-off-by: Mathias Nyman > --- > drivers/usb/host/xhci.c | 35 ++++++++++++++++++++++------------- > 1 file changed, 22 insertions(+), 13 deletions(-) > > diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c > index 9ac56e9ffc64..cb99bed5f755 100644 > --- a/drivers/usb/host/xhci.c > +++ b/drivers/usb/host/xhci.c > @@ -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; > This is not available to older kernels [< 5.19]. Can we get this backported to 5.15 as well? Please let me know if there is some other way to do it. Cc: # 5.15 Thanks, Prashanth K