6.6-stable review patch. If anyone has any objections, please let me know. ------------------ From: Oliver Neukum <oneukum@xxxxxxxx> commit 0583bc776ca5b5a3f5752869fc31cf7322df2b35 upstream. dwc2_hc_n_intr() writes back INTMASK as read but evaluates it with intmask applied. In stress testing this causes spurious interrupts like this: [Mon Aug 14 10:51:07 2023] dwc2 3f980000.usb: dwc2_hc_chhltd_intr_dma: Channel 7 - ChHltd set, but reason is unknown [Mon Aug 14 10:51:07 2023] dwc2 3f980000.usb: hcint 0x00000002, intsts 0x04600001 [Mon Aug 14 10:51:08 2023] dwc2 3f980000.usb: dwc2_hc_chhltd_intr_dma: Channel 0 - ChHltd set, but reason is unknown [Mon Aug 14 10:51:08 2023] dwc2 3f980000.usb: hcint 0x00000002, intsts 0x04600001 [Mon Aug 14 10:51:08 2023] dwc2 3f980000.usb: dwc2_hc_chhltd_intr_dma: Channel 4 - ChHltd set, but reason is unknown [Mon Aug 14 10:51:08 2023] dwc2 3f980000.usb: hcint 0x00000002, intsts 0x04600001 [Mon Aug 14 10:51:08 2023] dwc2 3f980000.usb: dwc2_update_urb_state_abn(): trimming xfer length Applying INTMASK prevents this. The issue exists in all versions of the driver. Signed-off-by: Oliver Neukum <oneukum@xxxxxxxx> Tested-by: Ivan Ivanov <ivan.ivanov@xxxxxxxx> Tested-by: Andrea della Porta <andrea.porta@xxxxxxxx> Link: https://lore.kernel.org/r/20231115144514.15248-1-oneukum@xxxxxxxx Cc: stable <stable@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/usb/dwc2/hcd_intr.c | 15 +++++++-------- 1 file changed, 7 insertions(+), 8 deletions(-) --- a/drivers/usb/dwc2/hcd_intr.c +++ b/drivers/usb/dwc2/hcd_intr.c @@ -2015,15 +2015,17 @@ static void dwc2_hc_n_intr(struct dwc2_h { struct dwc2_qtd *qtd; struct dwc2_host_chan *chan; - u32 hcint, hcintmsk; + u32 hcint, hcintraw, hcintmsk; chan = hsotg->hc_ptr_array[chnum]; - hcint = dwc2_readl(hsotg, HCINT(chnum)); + hcintraw = dwc2_readl(hsotg, HCINT(chnum)); hcintmsk = dwc2_readl(hsotg, HCINTMSK(chnum)); + hcint = hcintraw & hcintmsk; + dwc2_writel(hsotg, hcint, HCINT(chnum)); + if (!chan) { dev_err(hsotg->dev, "## hc_ptr_array for channel is NULL ##\n"); - dwc2_writel(hsotg, hcint, HCINT(chnum)); return; } @@ -2032,11 +2034,9 @@ static void dwc2_hc_n_intr(struct dwc2_h chnum); dev_vdbg(hsotg->dev, " hcint 0x%08x, hcintmsk 0x%08x, hcint&hcintmsk 0x%08x\n", - hcint, hcintmsk, hcint & hcintmsk); + hcintraw, hcintmsk, hcint); } - dwc2_writel(hsotg, hcint, HCINT(chnum)); - /* * If we got an interrupt after someone called * dwc2_hcd_endpoint_disable() we don't want to crash below @@ -2046,8 +2046,7 @@ static void dwc2_hc_n_intr(struct dwc2_h return; } - chan->hcint = hcint; - hcint &= hcintmsk; + chan->hcint = hcintraw; /* * If the channel was halted due to a dequeue, the qtd list might
