On Tue, Mar 21, 2023 at 10:36:36AM +0800, Haotien Hsu wrote:
> From: Wayne Chang <waynec@xxxxxxxxxx>
>
> When we set the OTG port to Host mode, we observed the following splat:
> [ 167.057718] BUG: sleeping function called from invalid context at
> include/linux/sched/mm.h:229
> [ 167.057872] Workqueue: events tegra_xusb_usb_phy_work
> [ 167.057954] Call trace:
> [ 167.057962] dump_backtrace+0x0/0x210
> [ 167.057996] show_stack+0x30/0x50
> [ 167.058020] dump_stack_lvl+0x64/0x84
> [ 167.058065] dump_stack+0x14/0x34
> [ 167.058100] __might_resched+0x144/0x180
> [ 167.058140] __might_sleep+0x64/0xd0
> [ 167.058171] slab_pre_alloc_hook.constprop.0+0xa8/0x110
> [ 167.058202] __kmalloc_track_caller+0x74/0x2b0
> [ 167.058233] kvasprintf+0xa4/0x190
> [ 167.058261] kasprintf+0x58/0x90
> [ 167.058285] tegra_xusb_find_port_node.isra.0+0x58/0xd0
> [ 167.058334] tegra_xusb_find_port+0x38/0xa0
> [ 167.058380] tegra_xusb_padctl_get_usb3_companion+0x38/0xd0
> [ 167.058430] tegra_xhci_id_notify+0x8c/0x1e0
> [ 167.058473] notifier_call_chain+0x88/0x100
> [ 167.058506] atomic_notifier_call_chain+0x44/0x70
> [ 167.058537] tegra_xusb_usb_phy_work+0x60/0xd0
> [ 167.058581] process_one_work+0x1dc/0x4c0
> [ 167.058618] worker_thread+0x54/0x410
> [ 167.058650] kthread+0x188/0x1b0
> [ 167.058672] ret_from_fork+0x10/0x20
>
> The function tegra_xusb_padctl_get_usb3_companion eventually calls
> tegra_xusb_find_port and this in turn calls kasprintf which might sleep
> and so cannot be called from an atomic context.
>
> Fix this by moving the call to tegra_xusb_padctl_get_usb3_companion to
> the tegra_xhci_id_work function where it is really needed.
>
> Fixes: f836e7843036 ("usb: xhci-tegra: Add OTG support")
> Cc: stable@xxxxxxxxxxxxxxx
> Signed-off-by: Wayne Chang <waynec@xxxxxxxxxx>
> Signed-off-by: Haotien Hsu <haotienh@xxxxxxxxxx>
> ---
> drivers/usb/host/xhci-tegra.c | 9 +++++----
> 1 file changed, 5 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/usb/host/xhci-tegra.c b/drivers/usb/host/xhci-tegra.c
> index 1ff22f675930..8dbce2cdb7e4 100644
> --- a/drivers/usb/host/xhci-tegra.c
> +++ b/drivers/usb/host/xhci-tegra.c
> @@ -2,7 +2,7 @@
> /*
> * NVIDIA Tegra xHCI host controller driver
> *
> - * Copyright (c) 2014-2020, NVIDIA CORPORATION. All rights reserved.
> + * Copyright (c) 2014-2020,2023, NVIDIA CORPORATION. All rights reserved.
> * Copyright (C) 2014 Google, Inc.
> */
>
> @@ -1360,6 +1360,10 @@ static void tegra_xhci_id_work(struct work_struct *work)
>
> mutex_unlock(&tegra->lock);
>
> + tegra->otg_usb3_port = tegra_xusb_padctl_get_usb3_companion(
> + tegra->padctl,
> + tegra->otg_usb2_port);
> +
> if (tegra->host_mode) {
> /* switch to host mode */
> if (tegra->otg_usb3_port >= 0) {
> @@ -1474,9 +1478,6 @@ static int tegra_xhci_id_notify(struct notifier_block *nb,
> }
>
> tegra->otg_usb2_port = tegra_xusb_get_usb2_port(tegra, usbphy);
> - tegra->otg_usb3_port = tegra_xusb_padctl_get_usb3_companion(
> - tegra->padctl,
> - tegra->otg_usb2_port);
>
> tegra->host_mode = (usbphy->last_event == USB_EVENT_ID) ? true : false;
>
> --
> 2.25.1
>
Hi,
This is the friendly patch-bot of Greg Kroah-Hartman. You have sent him
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If you wish to discuss this problem further, or you have questions about
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