diff mbox series

[v4] usb: xhci: tegra: fix sleep in atomic call

Message ID	20230321072946.935211-1-haotienh@nvidia.com
State	New
Headers	Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20; Received-SPF: Pass (protection.outlook.com: domain of nvidia.com designates 216.228.117.160 as permitted sender) receiver=protection.outlook.com; client-ip=216.228.117.160; helo=mail.nvidia.com; pr=C From: Haotien Hsu <haotienh@nvidia.com> To: Mathias Nyman <mathias.nyman@intel.com>, Greg Kroah-Hartman <gregkh@linuxfoundation.org>, Thierry Reding <thierry.reding@gmail.com>, Jonathan Hunter <jonathanh@nvidia.com>, Philipp Zabel <p.zabel@pengutronix.de>, <linux-usb@vger.kernel.org>, <linux-tegra@vger.kernel.org>, <linux-kernel@vger.kernel.org> CC: JC Kuo <jckuo@nvidia.com>, Wayne Chang <waynec@nvidia.com>, Haotien Hsu <haotienh@nvidia.com> Subject: [PATCH v4] usb: xhci: tegra: fix sleep in atomic call Date: Tue, 21 Mar 2023 15:29:46 +0800 Message-ID: <20230321072946.935211-1-haotienh@nvidia.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain Precedence: bulk
Series	[v4] usb: xhci: tegra: fix sleep in atomic call \| [v4] usb: xhci: tegra: fix sleep in atomic call

Commit Message

HaoTien Hsu March 21, 2023, 7:29 a.m. UTC

  From: Wayne Chang <waynec@nvidia.com>

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@vger.kernel.org
Signed-off-by: Wayne Chang <waynec@nvidia.com>
Signed-off-by: Haotien Hsu <haotienh@nvidia.com>
---
V3 -> V4: Remove copyright change from this patch
V2 -> V3: Add version information
V1 -> V2: Add "Fixes" and "Cc:" lines and update copyright years
---
 drivers/usb/host/xhci-tegra.c | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

Comments

Greg KH March 23, 2023, 4:22 p.m. UTC | #1

On Tue, Mar 21, 2023 at 03:29:46PM +0800, Haotien Hsu wrote:
> From: Wayne Chang <waynec@nvidia.com>
> 
> When we set the OTG port to Host mode, we observed the following splat:

What "OTG" port?  That is not a USB thing anymore at all.  How is this
part of a xhci controller?

> [  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@vger.kernel.org
> Signed-off-by: Wayne Chang <waynec@nvidia.com>
> Signed-off-by: Haotien Hsu <haotienh@nvidia.com>
> ---
> V3 -> V4: Remove copyright change from this patch
> V2 -> V3: Add version information
> V1 -> V2: Add "Fixes" and "Cc:" lines and update copyright years
> ---
>  drivers/usb/host/xhci-tegra.c | 7 ++++---
>  1 file changed, 4 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/usb/host/xhci-tegra.c b/drivers/usb/host/xhci-tegra.c
> index 1ff22f675930..b40e897ec092 100644
> --- a/drivers/usb/host/xhci-tegra.c
> +++ b/drivers/usb/host/xhci-tegra.c
> @@ -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);
> +

You have 100 columns, please use them, ending a line with "(" is not
generally a good idea.

thanks,

greg k-h

HaoTien Hsu March 24, 2023, 6:46 a.m. UTC | #2

On Thu, 2023-03-23 at 17:22 +0100, Greg Kroah-Hartman wrote:
> External email: Use caution opening links or attachments
> 
> 
> On Tue, Mar 21, 2023 at 03:29:46PM +0800, Haotien Hsu wrote:
> > From: Wayne Chang <waynec@nvidia.com>
> > 
> > When we set the OTG port to Host mode, we observed the following
> > splat:
> 
> What "OTG" port?  That is not a USB thing anymore at all.  How is
> this
> part of a xhci controller?

I will use 'dual-role port' instead.

When the role of a super-speed port is switched, we need to clear or
set port power.
Our host mode controller and device mode controller share the same
super-speed port hardware.
When a SS port is going to be switched to device mode role, we have to
clear PP at host mode controller side to release SS port hardware to
device mode controller.
When a SS port is going to be switched to host mode role, we have to
set PP at host mode controller side to acquire SS port hardware.

> 
> > [  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@vger.kernel.org
> > Signed-off-by: Wayne Chang <waynec@nvidia.com>
> > Signed-off-by: Haotien Hsu <haotienh@nvidia.com>
> > ---
> > V3 -> V4: Remove copyright change from this patch
> > V2 -> V3: Add version information
> > V1 -> V2: Add "Fixes" and "Cc:" lines and update copyright years
> > ---
> >  drivers/usb/host/xhci-tegra.c | 7 ++++---
> >  1 file changed, 4 insertions(+), 3 deletions(-)
> > 
> > diff --git a/drivers/usb/host/xhci-tegra.c b/drivers/usb/host/xhci-
> > tegra.c
> > index 1ff22f675930..b40e897ec092 100644
> > --- a/drivers/usb/host/xhci-tegra.c
> > +++ b/drivers/usb/host/xhci-tegra.c
> > @@ -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);
> > +
> 
> You have 100 columns, please use them, ending a line with "(" is not
> generally a good idea.

I will resubmit a new patch.

> 
> thanks,
> 
> greg k-h

HaoTien Hsu March 24, 2023, 9:34 a.m. UTC | #3

On Fri, 2023-03-24 at 06:46 +0000, Haotien Hsu wrote:
> On Thu, 2023-03-23 at 17:22 +0100, Greg Kroah-Hartman wrote:
> > External email: Use caution opening links or attachments
> > 
> > 
> > On Tue, Mar 21, 2023 at 03:29:46PM +0800, Haotien Hsu wrote:
> > > From: Wayne Chang <waynec@nvidia.com>
> > > 
> > > When we set the OTG port to Host mode, we observed the following
> > > splat:
> > 
> > What "OTG" port?  That is not a USB thing anymore at all.  How is
> > this
> > part of a xhci controller?
> 
> I will use 'dual-role port' instead.
> 
> When the role of a super-speed port is switched, we need to clear or
> set XHCI PORTSC.PP.
> Our host mode controller and device mode controller share the same
> super-speed port hardware.
> When a super-speed port is going to be switched to device mode role,
> we have to clear XHCI PORTSC.PP at host mode controller side to
> release super-speed port hardware to device mode controller.
> When a super-speed port is going to be switched to host mode role, we
> have to set XHCI PORTSC.PP at host mode controller side to
> acquire super-speed port hardware.
> 
I replaced SS with super-speed and PP with 'XHCI PORTSC.PP' in the
above description to make it clear.

> > > [  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@vger.kernel.org
> > > Signed-off-by: Wayne Chang <waynec@nvidia.com>
> > > Signed-off-by: Haotien Hsu <haotienh@nvidia.com>
> > > ---
> > > V3 -> V4: Remove copyright change from this patch
> > > V2 -> V3: Add version information
> > > V1 -> V2: Add "Fixes" and "Cc:" lines and update copyright years
> > > ---
> > >  drivers/usb/host/xhci-tegra.c | 7 ++++---
> > >  1 file changed, 4 insertions(+), 3 deletions(-)
> > > 
> > > diff --git a/drivers/usb/host/xhci-tegra.c
> > > b/drivers/usb/host/xhci-
> > > tegra.c
> > > index 1ff22f675930..b40e897ec092 100644
> > > --- a/drivers/usb/host/xhci-tegra.c
> > > +++ b/drivers/usb/host/xhci-tegra.c
> > > @@ -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);
> > > +
> > 
> > You have 100 columns, please use them, ending a line with "(" is
> > not
> > generally a good idea.
> 
> I will resubmit a new patch.
> 
> > thanks,
> > 
> > greg k-h

diff mbox series

Patch

diff --git a/drivers/usb/host/xhci-tegra.c b/drivers/usb/host/xhci-tegra.c
index 1ff22f675930..b40e897ec092 100644
--- a/drivers/usb/host/xhci-tegra.c
+++ b/drivers/usb/host/xhci-tegra.c
@@ -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;