This is a note to let you know that I've just added the patch titled r8152: Increase USB control msg timeout to 5000ms as per spec to the 5.4-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: r8152-increase-usb-control-msg-timeout-to-5000ms-as-.patch and it can be found in the queue-5.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit a59209469a674eb82268f81db7fd267ed59cb202 Author: Douglas Anderson <dianders@xxxxxxxxxxxx> Date: Fri Oct 20 14:06:52 2023 -0700 r8152: Increase USB control msg timeout to 5000ms as per spec [ Upstream commit a5feba71ec9c14a54c3babdc732c5b6866d8ee43 ] According to the comment next to USB_CTRL_GET_TIMEOUT and USB_CTRL_SET_TIMEOUT, although sending/receiving control messages is usually quite fast, the spec allows them to take up to 5 seconds. Let's increase the timeout in the Realtek driver from 500ms to 5000ms (using the #defines) to account for this. This is not just a theoretical change. The need for the longer timeout was seen in testing. Specifically, if you drop a sc7180-trogdor based Chromebook into the kdb debugger and then "go" again after sitting in the debugger for a while, the next USB control message takes a long time. Out of ~40 tests the slowest USB control message was 4.5 seconds. While dropping into kdb is not exactly an end-user scenario, the above is similar to what could happen due to an temporary interrupt storm, what could happen if there was a host controller (HW or SW) issue, or what could happen if the Realtek device got into a confused state and needed time to recover. This change is fairly critical since the r8152 driver in Linux doesn't expect register reads/writes (which are backed by USB control messages) to fail. Fixes: ac718b69301c ("net/usb: new driver for RTL8152") Suggested-by: Hayes Wang <hayeswang@xxxxxxxxxxx> Signed-off-by: Douglas Anderson <dianders@xxxxxxxxxxxx> Reviewed-by: Grant Grundler <grundler@xxxxxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/net/usb/r8152.c b/drivers/net/usb/r8152.c index a19f0431e6f99..fa13a19e844c1 100644 --- a/drivers/net/usb/r8152.c +++ b/drivers/net/usb/r8152.c @@ -850,7 +850,7 @@ int get_registers(struct r8152 *tp, u16 value, u16 index, u16 size, void *data) ret = usb_control_msg(tp->udev, usb_rcvctrlpipe(tp->udev, 0), RTL8152_REQ_GET_REGS, RTL8152_REQT_READ, - value, index, tmp, size, 500); + value, index, tmp, size, USB_CTRL_GET_TIMEOUT); if (ret < 0) memset(data, 0xff, size); else @@ -873,7 +873,7 @@ int set_registers(struct r8152 *tp, u16 value, u16 index, u16 size, void *data) ret = usb_control_msg(tp->udev, usb_sndctrlpipe(tp->udev, 0), RTL8152_REQ_SET_REGS, RTL8152_REQT_WRITE, - value, index, tmp, size, 500); + value, index, tmp, size, USB_CTRL_SET_TIMEOUT); kfree(tmp); @@ -5584,7 +5584,8 @@ static u8 rtl_get_version(struct usb_interface *intf) ret = usb_control_msg(udev, usb_rcvctrlpipe(udev, 0), RTL8152_REQ_GET_REGS, RTL8152_REQT_READ, - PLA_TCR0, MCU_TYPE_PLA, tmp, sizeof(*tmp), 500); + PLA_TCR0, MCU_TYPE_PLA, tmp, sizeof(*tmp), + USB_CTRL_GET_TIMEOUT); if (ret > 0) ocp_data = (__le32_to_cpu(*tmp) >> 16) & VERSION_MASK;