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usb: dwc3: gadget: Fix suspend/resume warning when no-gadget is connected

PATCH In review Michael Trimarchi 3 participants 7 messages Feb 26, 2024 – Mar 7, 2024

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#0 lore raw

PATCH v3 1/1 usb: dwc3: gadget: Fix suspend/resume warning when no-gadget is connected

This patch avoid to disconnect an already gadget in not connected state

[   45.597274] dwc3 31000000.usb: wait for SETUP phase timed out
[   45.599140] dwc3 31000000.usb: failed to set STALL on ep0out
[   45.601069] ------------[ cut here ]------------
[   45.601073] WARNING: CPU: 0 PID: 150 at drivers/usb/dwc3/ep0.c:289 dwc3_ep0_out_start+0xcc/0xd4
[   45.601102] Modules linked in: cfg80211 rfkill ipv6 rpmsg_ctrl rpmsg_char crct10dif_ce rti_wdt k3_j72xx_bandgap rtc_ti_k3 omap_mailbox sa2ul authenc [last unloaded: ti_k3_r5_remoteproc]
[   45.601151] CPU: 0 PID: 150 Comm: sh Not tainted 6.8.0-rc5 #1
[   45.601159] Hardware name: BSH - CCM-M3 (DT)
[   45.601164] pstate: 600000c5 (nZCv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[   45.601172] pc : dwc3_ep0_out_start+0xcc/0xd4
[   45.601179] lr : dwc3_ep0_out_start+0x50/0xd4
[   45.601186] sp : ffff8000832739e0
[   45.601189] x29: ffff8000832739e0 x28: ffff800082a21000 x27: ffff8000808dc630
[   45.601200] x26: 0000000000000002 x25: ffff800082530a44 x24: 0000000000000000
[   45.601210] x23: ffff000000e079a0 x22: ffff000000e07a68 x21: 0000000000000001
[   45.601219] x20: ffff000000e07880 x19: ffff000000e07880 x18: 0000000000000040
[   45.601229] x17: ffff7fff8e1ce000 x16: ffff800080000000 x15: fffffffffffe5260
[   45.601239] x14: 0000000000000000 x13: 206e6f204c4c4154 x12: 5320746573206f74
[   45.601249] x11: 0000000000000001 x10: 000000000000000a x9 : ffff800083273930
[   45.601259] x8 : 000000000000000a x7 : ffffffffffff3f0c x6 : ffffffffffff3f00
[   45.601268] x5 : ffffffffffff3f0c x4 : 0000000000000000 x3 : 0000000000000000
[   45.601278] x2 : 0000000000000000 x1 : ffff000004e7e600 x0 : 00000000ffffff92
[   45.601289] Call trace:
[   45.601293]  dwc3_ep0_out_start+0xcc/0xd4
[   45.601301]  dwc3_ep0_stall_and_restart+0x98/0xbc
[   45.601309]  dwc3_ep0_reset_state+0x5c/0x88
[   45.601315]  dwc3_gadget_soft_disconnect+0x144/0x160
[   45.601323]  dwc3_gadget_suspend+0x18/0xb0
[   45.601329]  dwc3_suspend_common+0x5c/0x18c
[   45.601341]  dwc3_suspend+0x20/0x44
[   45.601350]  platform_pm_suspend+0x2c/0x6c
[   45.601360]  __device_suspend+0x10c/0x34c
[   45.601372]  dpm_suspend+0x1a8/0x240
[   45.601382]  dpm_suspend_start+0x80/0x9c
[   45.601391]  suspend_devices_and_enter+0x1c4/0x584
[   45.601402]  pm_suspend+0x1b0/0x264
[   45.601408]  state_store+0x80/0xec
[   45.601415]  kobj_attr_store+0x18/0x2c
[   45.601426]  sysfs_kf_write+0x44/0x54
[   45.601434]  kernfs_fop_write_iter+0x120/0x1ec
[   45.601445]  vfs_write+0x23c/0x358
[   45.601458]  ksys_write+0x70/0x104
[   45.601467]  __arm64_sys_write+0x1c/0x28
[   45.601477]  invoke_syscall+0x48/0x114
[   45.601488]  el0_svc_common.constprop.0+0x40/0xe0
[   45.601498]  do_el0_svc+0x1c/0x28
[   45.601506]  el0_svc+0x34/0xb8
[   45.601516]  el0t_64_sync_handler+0x100/0x12c
[   45.601522]  el0t_64_sync+0x190/0x194
[   45.601531] ---[ end trace 0000000000000000 ]---
[   45.608794] Disabling non-boot CPUs ...
[   45.611029] psci: CPU1 killed (polled 0 ms)
[   45.611837] Enabling non-boot CPUs ...
[   45.612247] Detected VIPT I-cache on CPU1

Tested on a am62x board with a usbnet gadget

Fixes 61a348857e86 ("usb: dwc3: gadget: Fix NULL pointer dereference in dwc3_gadget_suspend)

---
V2->V3:
- Change the logic of the patch using the gadget connected state
- Change of the commit message
V1->V2:
- Add stable in CC

---
 drivers/usb/dwc3/gadget.c | 9 +++++++++
 1 file changed, 9 insertions(+)
drivers/usb/dwc3/gadget.c +9 -0
index 4c8dd6724678..a7316a1703ad 100644
@@ -2650,6 +2650,15 @@ static int dwc3_gadget_soft_disconnect(struct dwc3 *dwc)
 	int ret;
 
 	spin_lock_irqsave(&dwc->lock, flags);
+	/*
+	 * Attempt to disconnect a no connected gadget
+	 */
+	if (!dwc->connected) {
+		dev_warn(dwc->dev, "No connected device\n");
+		spin_unlock_irqrestore(&dwc->lock, flags);
+		return 0;
+	}
+
 	dwc->connected = false;
 
 	/*
Signature · 1 line
2.40.1
#1 lore raw
Quoted 76 lines · Michael Trimarchi

This patch avoid to disconnect an already gadget in not connected state

[   45.597274] dwc3 31000000.usb: wait for SETUP phase timed out
[   45.599140] dwc3 31000000.usb: failed to set STALL on ep0out
[   45.601069] ------------[ cut here ]------------
[   45.601073] WARNING: CPU: 0 PID: 150 at drivers/usb/dwc3/ep0.c:289 dwc3_ep0_out_start+0xcc/0xd4
[   45.601102] Modules linked in: cfg80211 rfkill ipv6 rpmsg_ctrl rpmsg_char crct10dif_ce rti_wdt k3_j72xx_bandgap rtc_ti_k3 omap_mailbox sa2ul authenc [last unloaded: ti_k3_r5_remoteproc]
[   45.601151] CPU: 0 PID: 150 Comm: sh Not tainted 6.8.0-rc5 #1
[   45.601159] Hardware name: BSH - CCM-M3 (DT)
[   45.601164] pstate: 600000c5 (nZCv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[   45.601172] pc : dwc3_ep0_out_start+0xcc/0xd4
[   45.601179] lr : dwc3_ep0_out_start+0x50/0xd4
[   45.601186] sp : ffff8000832739e0
[   45.601189] x29: ffff8000832739e0 x28: ffff800082a21000 x27: ffff8000808dc630
[   45.601200] x26: 0000000000000002 x25: ffff800082530a44 x24: 0000000000000000
[   45.601210] x23: ffff000000e079a0 x22: ffff000000e07a68 x21: 0000000000000001
[   45.601219] x20: ffff000000e07880 x19: ffff000000e07880 x18: 0000000000000040
[   45.601229] x17: ffff7fff8e1ce000 x16: ffff800080000000 x15: fffffffffffe5260
[   45.601239] x14: 0000000000000000 x13: 206e6f204c4c4154 x12: 5320746573206f74
[   45.601249] x11: 0000000000000001 x10: 000000000000000a x9 : ffff800083273930
[   45.601259] x8 : 000000000000000a x7 : ffffffffffff3f0c x6 : ffffffffffff3f00
[   45.601268] x5 : ffffffffffff3f0c x4 : 0000000000000000 x3 : 0000000000000000
[   45.601278] x2 : 0000000000000000 x1 : ffff000004e7e600 x0 : 00000000ffffff92
[   45.601289] Call trace:
[   45.601293]  dwc3_ep0_out_start+0xcc/0xd4
[   45.601301]  dwc3_ep0_stall_and_restart+0x98/0xbc
[   45.601309]  dwc3_ep0_reset_state+0x5c/0x88
[   45.601315]  dwc3_gadget_soft_disconnect+0x144/0x160
[   45.601323]  dwc3_gadget_suspend+0x18/0xb0
[   45.601329]  dwc3_suspend_common+0x5c/0x18c
[   45.601341]  dwc3_suspend+0x20/0x44
[   45.601350]  platform_pm_suspend+0x2c/0x6c
[   45.601360]  __device_suspend+0x10c/0x34c
[   45.601372]  dpm_suspend+0x1a8/0x240
[   45.601382]  dpm_suspend_start+0x80/0x9c
[   45.601391]  suspend_devices_and_enter+0x1c4/0x584
[   45.601402]  pm_suspend+0x1b0/0x264
[   45.601408]  state_store+0x80/0xec
[   45.601415]  kobj_attr_store+0x18/0x2c
[   45.601426]  sysfs_kf_write+0x44/0x54
[   45.601434]  kernfs_fop_write_iter+0x120/0x1ec
[   45.601445]  vfs_write+0x23c/0x358
[   45.601458]  ksys_write+0x70/0x104
[   45.601467]  __arm64_sys_write+0x1c/0x28
[   45.601477]  invoke_syscall+0x48/0x114
[   45.601488]  el0_svc_common.constprop.0+0x40/0xe0
[   45.601498]  do_el0_svc+0x1c/0x28
[   45.601506]  el0_svc+0x34/0xb8
[   45.601516]  el0t_64_sync_handler+0x100/0x12c
[   45.601522]  el0t_64_sync+0x190/0x194
[   45.601531] ---[ end trace 0000000000000000 ]---
[   45.608794] Disabling non-boot CPUs ...
[   45.611029] psci: CPU1 killed (polled 0 ms)
[   45.611837] Enabling non-boot CPUs ...
[   45.612247] Detected VIPT I-cache on CPU1

Tested on a am62x board with a usbnet gadget

Fixes 61a348857e86 ("usb: dwc3: gadget: Fix NULL pointer dereference in dwc3_gadget_suspend)

---
V2->V3:
- Change the logic of the patch using the gadget connected state
- Change of the commit message
V1->V2:
- Add stable in CC

---
 drivers/usb/dwc3/gadget.c | 9 +++++++++
 1 file changed, 9 insertions(+)
drivers/usb/dwc3/gadget.c +0 -0
index 4c8dd6724678..a7316a1703ad 100644

drivers/usb/dwc3/gadget.c static int dwc3_gadget_soft_disconnect(struct dwc3 *dwc) · line 2654

Quoted 5 lines
drivers/usb/dwc3/gadget.c +2 -0
@@ -2650,6 +2650,15 @@ static int dwc3_gadget_soft_disconnect(struct dwc3 *dwc)
 	int ret;
 
 	spin_lock_irqsave(&dwc->lock, flags);
+	/*
+	 * Attempt to disconnect a no connected gadget

What does this mean? And why a 3 line comment?

drivers/usb/dwc3/gadget.c static int dwc3_gadget_soft_disconnect(struct dwc3 *dwc) · line 2657

Quoted 3 lines
drivers/usb/dwc3/gadget.c +3 -0
+	 */
+	if (!dwc->connected) {
+		dev_warn(dwc->dev, "No connected device\n");

You are printing while a spinlock is held? What can userspace do with this message?

drivers/usb/dwc3/gadget.c static int dwc3_gadget_soft_disconnect(struct dwc3 *dwc) · line 2659

Quoted 2 lines
drivers/usb/dwc3/gadget.c +2 -0
+		spin_unlock_irqrestore(&dwc->lock, flags);
+		return 0;

No error handling? Why not?

thanks,

greg k-h

#2 lore raw

Hi Greg

Quoted 86 lines · Greg Kroah-Hartman
Quoted 76 lines · Michael Trimarchi

This patch avoid to disconnect an already gadget in not connected state

[   45.597274] dwc3 31000000.usb: wait for SETUP phase timed out
[   45.599140] dwc3 31000000.usb: failed to set STALL on ep0out
[   45.601069] ------------[ cut here ]------------
[   45.601073] WARNING: CPU: 0 PID: 150 at drivers/usb/dwc3/ep0.c:289 dwc3_ep0_out_start+0xcc/0xd4
[   45.601102] Modules linked in: cfg80211 rfkill ipv6 rpmsg_ctrl rpmsg_char crct10dif_ce rti_wdt k3_j72xx_bandgap rtc_ti_k3 omap_mailbox sa2ul authenc [last unloaded: ti_k3_r5_remoteproc]
[   45.601151] CPU: 0 PID: 150 Comm: sh Not tainted 6.8.0-rc5 #1
[   45.601159] Hardware name: BSH - CCM-M3 (DT)
[   45.601164] pstate: 600000c5 (nZCv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[   45.601172] pc : dwc3_ep0_out_start+0xcc/0xd4
[   45.601179] lr : dwc3_ep0_out_start+0x50/0xd4
[   45.601186] sp : ffff8000832739e0
[   45.601189] x29: ffff8000832739e0 x28: ffff800082a21000 x27: ffff8000808dc630
[   45.601200] x26: 0000000000000002 x25: ffff800082530a44 x24: 0000000000000000
[   45.601210] x23: ffff000000e079a0 x22: ffff000000e07a68 x21: 0000000000000001
[   45.601219] x20: ffff000000e07880 x19: ffff000000e07880 x18: 0000000000000040
[   45.601229] x17: ffff7fff8e1ce000 x16: ffff800080000000 x15: fffffffffffe5260
[   45.601239] x14: 0000000000000000 x13: 206e6f204c4c4154 x12: 5320746573206f74
[   45.601249] x11: 0000000000000001 x10: 000000000000000a x9 : ffff800083273930
[   45.601259] x8 : 000000000000000a x7 : ffffffffffff3f0c x6 : ffffffffffff3f00
[   45.601268] x5 : ffffffffffff3f0c x4 : 0000000000000000 x3 : 0000000000000000
[   45.601278] x2 : 0000000000000000 x1 : ffff000004e7e600 x0 : 00000000ffffff92
[   45.601289] Call trace:
[   45.601293]  dwc3_ep0_out_start+0xcc/0xd4
[   45.601301]  dwc3_ep0_stall_and_restart+0x98/0xbc
[   45.601309]  dwc3_ep0_reset_state+0x5c/0x88
[   45.601315]  dwc3_gadget_soft_disconnect+0x144/0x160
[   45.601323]  dwc3_gadget_suspend+0x18/0xb0
[   45.601329]  dwc3_suspend_common+0x5c/0x18c
[   45.601341]  dwc3_suspend+0x20/0x44
[   45.601350]  platform_pm_suspend+0x2c/0x6c
[   45.601360]  __device_suspend+0x10c/0x34c
[   45.601372]  dpm_suspend+0x1a8/0x240
[   45.601382]  dpm_suspend_start+0x80/0x9c
[   45.601391]  suspend_devices_and_enter+0x1c4/0x584
[   45.601402]  pm_suspend+0x1b0/0x264
[   45.601408]  state_store+0x80/0xec
[   45.601415]  kobj_attr_store+0x18/0x2c
[   45.601426]  sysfs_kf_write+0x44/0x54
[   45.601434]  kernfs_fop_write_iter+0x120/0x1ec
[   45.601445]  vfs_write+0x23c/0x358
[   45.601458]  ksys_write+0x70/0x104
[   45.601467]  __arm64_sys_write+0x1c/0x28
[   45.601477]  invoke_syscall+0x48/0x114
[   45.601488]  el0_svc_common.constprop.0+0x40/0xe0
[   45.601498]  do_el0_svc+0x1c/0x28
[   45.601506]  el0_svc+0x34/0xb8
[   45.601516]  el0t_64_sync_handler+0x100/0x12c
[   45.601522]  el0t_64_sync+0x190/0x194
[   45.601531] ---[ end trace 0000000000000000 ]---
[   45.608794] Disabling non-boot CPUs ...
[   45.611029] psci: CPU1 killed (polled 0 ms)
[   45.611837] Enabling non-boot CPUs ...
[   45.612247] Detected VIPT I-cache on CPU1

Tested on a am62x board with a usbnet gadget

Fixes 61a348857e86 ("usb: dwc3: gadget: Fix NULL pointer dereference in dwc3_gadget_suspend)

---
V2->V3:
- Change the logic of the patch using the gadget connected state
- Change of the commit message
V1->V2:
- Add stable in CC

---
 drivers/usb/dwc3/gadget.c | 9 +++++++++
 1 file changed, 9 insertions(+)
drivers/usb/dwc3/gadget.c +0 -0
index 4c8dd6724678..a7316a1703ad 100644

drivers/usb/dwc3/gadget.c static int dwc3_gadget_soft_disconnect(struct dwc3 *dwc) · line 2654

Quoted 5 lines
drivers/usb/dwc3/gadget.c +2 -0
@@ -2650,6 +2650,15 @@ static int dwc3_gadget_soft_disconnect(struct dwc3 *dwc)
      int ret;
 
      spin_lock_irqsave(&dwc->lock, flags);
+     /*
+      * Attempt to disconnect a no connected gadget

What does this mean? And why a 3 line comment?

Quoted 6 lines

drivers/usb/dwc3/gadget.c static int dwc3_gadget_soft_disconnect(struct dwc3 *dwc) · line 2657

Quoted 3 lines
drivers/usb/dwc3/gadget.c +3 -0
+      */
+     if (!dwc->connected) {
+             dev_warn(dwc->dev, "No connected device\n");

You are printing while a spinlock is held? What can userspace do with this message?

I will drop it.

Quoted 5 lines

drivers/usb/dwc3/gadget.c static int dwc3_gadget_soft_disconnect(struct dwc3 *dwc) · line 2659

Quoted 3 lines
drivers/usb/dwc3/gadget.c +2 -0
+             spin_unlock_irqrestore(&dwc->lock, flags);
+             return 0;

No error handling? Why not?

The function tries to disconnect an already disconnected gadget, so in this case is a nop. If we want to handle
an error I can check the impact on the dwc3 gadget.

Michael

Quoted 4 lines

thanks,

greg k-h

Signature · 11 lines
Michael Nazzareno Trimarchi
Co-Founder & Chief Executive Officer
M. +39 347 913 2170
[email protected]
__________________________________

Amarula Solutions BV
Joop Geesinkweg 125, 1114 AB, Amsterdam, NL
T. +31 (0)85 111 9172
[email protected]
www.amarulasolutions.com
maintainer
#3 lore raw
In reply to Michael Trimarchi

Hi,

Quoted 94 lines · Michael Trimarchi

This patch avoid to disconnect an already gadget in not connected state

[   45.597274] dwc3 31000000.usb: wait for SETUP phase timed out
[   45.599140] dwc3 31000000.usb: failed to set STALL on ep0out
[   45.601069] ------------[ cut here ]------------
[   45.601073] WARNING: CPU: 0 PID: 150 at drivers/usb/dwc3/ep0.c:289 dwc3_ep0_out_start+0xcc/0xd4
[   45.601102] Modules linked in: cfg80211 rfkill ipv6 rpmsg_ctrl rpmsg_char crct10dif_ce rti_wdt k3_j72xx_bandgap rtc_ti_k3 omap_mailbox sa2ul authenc [last unloaded: ti_k3_r5_remoteproc]
[   45.601151] CPU: 0 PID: 150 Comm: sh Not tainted 6.8.0-rc5 #1
[   45.601159] Hardware name: BSH - CCM-M3 (DT)
[   45.601164] pstate: 600000c5 (nZCv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[   45.601172] pc : dwc3_ep0_out_start+0xcc/0xd4
[   45.601179] lr : dwc3_ep0_out_start+0x50/0xd4
[   45.601186] sp : ffff8000832739e0
[   45.601189] x29: ffff8000832739e0 x28: ffff800082a21000 x27: ffff8000808dc630
[   45.601200] x26: 0000000000000002 x25: ffff800082530a44 x24: 0000000000000000
[   45.601210] x23: ffff000000e079a0 x22: ffff000000e07a68 x21: 0000000000000001
[   45.601219] x20: ffff000000e07880 x19: ffff000000e07880 x18: 0000000000000040
[   45.601229] x17: ffff7fff8e1ce000 x16: ffff800080000000 x15: fffffffffffe5260
[   45.601239] x14: 0000000000000000 x13: 206e6f204c4c4154 x12: 5320746573206f74
[   45.601249] x11: 0000000000000001 x10: 000000000000000a x9 : ffff800083273930
[   45.601259] x8 : 000000000000000a x7 : ffffffffffff3f0c x6 : ffffffffffff3f00
[   45.601268] x5 : ffffffffffff3f0c x4 : 0000000000000000 x3 : 0000000000000000
[   45.601278] x2 : 0000000000000000 x1 : ffff000004e7e600 x0 : 00000000ffffff92
[   45.601289] Call trace:
[   45.601293]  dwc3_ep0_out_start+0xcc/0xd4
[   45.601301]  dwc3_ep0_stall_and_restart+0x98/0xbc
[   45.601309]  dwc3_ep0_reset_state+0x5c/0x88
[   45.601315]  dwc3_gadget_soft_disconnect+0x144/0x160
[   45.601323]  dwc3_gadget_suspend+0x18/0xb0
[   45.601329]  dwc3_suspend_common+0x5c/0x18c
[   45.601341]  dwc3_suspend+0x20/0x44
[   45.601350]  platform_pm_suspend+0x2c/0x6c
[   45.601360]  __device_suspend+0x10c/0x34c
[   45.601372]  dpm_suspend+0x1a8/0x240
[   45.601382]  dpm_suspend_start+0x80/0x9c
[   45.601391]  suspend_devices_and_enter+0x1c4/0x584
[   45.601402]  pm_suspend+0x1b0/0x264
[   45.601408]  state_store+0x80/0xec
[   45.601415]  kobj_attr_store+0x18/0x2c
[   45.601426]  sysfs_kf_write+0x44/0x54
[   45.601434]  kernfs_fop_write_iter+0x120/0x1ec
[   45.601445]  vfs_write+0x23c/0x358
[   45.601458]  ksys_write+0x70/0x104
[   45.601467]  __arm64_sys_write+0x1c/0x28
[   45.601477]  invoke_syscall+0x48/0x114
[   45.601488]  el0_svc_common.constprop.0+0x40/0xe0
[   45.601498]  do_el0_svc+0x1c/0x28
[   45.601506]  el0_svc+0x34/0xb8
[   45.601516]  el0t_64_sync_handler+0x100/0x12c
[   45.601522]  el0t_64_sync+0x190/0x194
[   45.601531] ---[ end trace 0000000000000000 ]---
[   45.608794] Disabling non-boot CPUs ...
[   45.611029] psci: CPU1 killed (polled 0 ms)
[   45.611837] Enabling non-boot CPUs ...
[   45.612247] Detected VIPT I-cache on CPU1

Tested on a am62x board with a usbnet gadget

Fixes 61a348857e86 ("usb: dwc3: gadget: Fix NULL pointer dereference in dwc3_gadget_suspend)

---
V2->V3:
- Change the logic of the patch using the gadget connected state
- Change of the commit message
V1->V2:
- Add stable in CC

---
 drivers/usb/dwc3/gadget.c | 9 +++++++++
 1 file changed, 9 insertions(+)
drivers/usb/dwc3/gadget.c +9 -0
index 4c8dd6724678..a7316a1703ad 100644
@@ -2650,6 +2650,15 @@ static int dwc3_gadget_soft_disconnect(struct dwc3 *dwc)
 	int ret;
 
 	spin_lock_irqsave(&dwc->lock, flags);
+	/*
+	 * Attempt to disconnect a no connected gadget
+	 */
+	if (!dwc->connected) {
+		dev_warn(dwc->dev, "No connected device\n");
+		spin_unlock_irqrestore(&dwc->lock, flags);
+		return 0;
+	}
+
 	dwc->connected = false;
 
 	/*
Signature · 1 line
2.40.1

There's already a fix for this, and it's already in mainline. Let me know if this works for you:

https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=b191a18cb5c47109ca696370a74a5062a70adfd0

Thanks,
Thinh

#4 lore raw

Hi

Quoted 102 lines · Thinh Nguyen

Hi,

Quoted 92 lines · Michael Trimarchi

This patch avoid to disconnect an already gadget in not connected state

[   45.597274] dwc3 31000000.usb: wait for SETUP phase timed out
[   45.599140] dwc3 31000000.usb: failed to set STALL on ep0out
[   45.601069] ------------[ cut here ]------------
[   45.601073] WARNING: CPU: 0 PID: 150 at drivers/usb/dwc3/ep0.c:289 dwc3_ep0_out_start+0xcc/0xd4
[   45.601102] Modules linked in: cfg80211 rfkill ipv6 rpmsg_ctrl rpmsg_char crct10dif_ce rti_wdt k3_j72xx_bandgap rtc_ti_k3 omap_mailbox sa2ul authenc [last unloaded: ti_k3_r5_remoteproc]
[   45.601151] CPU: 0 PID: 150 Comm: sh Not tainted 6.8.0-rc5 #1
[   45.601159] Hardware name: BSH - CCM-M3 (DT)
[   45.601164] pstate: 600000c5 (nZCv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[   45.601172] pc : dwc3_ep0_out_start+0xcc/0xd4
[   45.601179] lr : dwc3_ep0_out_start+0x50/0xd4
[   45.601186] sp : ffff8000832739e0
[   45.601189] x29: ffff8000832739e0 x28: ffff800082a21000 x27: ffff8000808dc630
[   45.601200] x26: 0000000000000002 x25: ffff800082530a44 x24: 0000000000000000
[   45.601210] x23: ffff000000e079a0 x22: ffff000000e07a68 x21: 0000000000000001
[   45.601219] x20: ffff000000e07880 x19: ffff000000e07880 x18: 0000000000000040
[   45.601229] x17: ffff7fff8e1ce000 x16: ffff800080000000 x15: fffffffffffe5260
[   45.601239] x14: 0000000000000000 x13: 206e6f204c4c4154 x12: 5320746573206f74
[   45.601249] x11: 0000000000000001 x10: 000000000000000a x9 : ffff800083273930
[   45.601259] x8 : 000000000000000a x7 : ffffffffffff3f0c x6 : ffffffffffff3f00
[   45.601268] x5 : ffffffffffff3f0c x4 : 0000000000000000 x3 : 0000000000000000
[   45.601278] x2 : 0000000000000000 x1 : ffff000004e7e600 x0 : 00000000ffffff92
[   45.601289] Call trace:
[   45.601293]  dwc3_ep0_out_start+0xcc/0xd4
[   45.601301]  dwc3_ep0_stall_and_restart+0x98/0xbc
[   45.601309]  dwc3_ep0_reset_state+0x5c/0x88
[   45.601315]  dwc3_gadget_soft_disconnect+0x144/0x160
[   45.601323]  dwc3_gadget_suspend+0x18/0xb0
[   45.601329]  dwc3_suspend_common+0x5c/0x18c
[   45.601341]  dwc3_suspend+0x20/0x44
[   45.601350]  platform_pm_suspend+0x2c/0x6c
[   45.601360]  __device_suspend+0x10c/0x34c
[   45.601372]  dpm_suspend+0x1a8/0x240
[   45.601382]  dpm_suspend_start+0x80/0x9c
[   45.601391]  suspend_devices_and_enter+0x1c4/0x584
[   45.601402]  pm_suspend+0x1b0/0x264
[   45.601408]  state_store+0x80/0xec
[   45.601415]  kobj_attr_store+0x18/0x2c
[   45.601426]  sysfs_kf_write+0x44/0x54
[   45.601434]  kernfs_fop_write_iter+0x120/0x1ec
[   45.601445]  vfs_write+0x23c/0x358
[   45.601458]  ksys_write+0x70/0x104
[   45.601467]  __arm64_sys_write+0x1c/0x28
[   45.601477]  invoke_syscall+0x48/0x114
[   45.601488]  el0_svc_common.constprop.0+0x40/0xe0
[   45.601498]  do_el0_svc+0x1c/0x28
[   45.601506]  el0_svc+0x34/0xb8
[   45.601516]  el0t_64_sync_handler+0x100/0x12c
[   45.601522]  el0t_64_sync+0x190/0x194
[   45.601531] ---[ end trace 0000000000000000 ]---
[   45.608794] Disabling non-boot CPUs ...
[   45.611029] psci: CPU1 killed (polled 0 ms)
[   45.611837] Enabling non-boot CPUs ...
[   45.612247] Detected VIPT I-cache on CPU1

Tested on a am62x board with a usbnet gadget

Fixes 61a348857e86 ("usb: dwc3: gadget: Fix NULL pointer dereference in dwc3_gadget_suspend)

---
V2->V3:
- Change the logic of the patch using the gadget connected state
- Change of the commit message
V1->V2:
- Add stable in CC

---
 drivers/usb/dwc3/gadget.c | 9 +++++++++
 1 file changed, 9 insertions(+)
drivers/usb/dwc3/gadget.c +9 -1
index 4c8dd6724678..a7316a1703ad 100644
@@ -2650,6 +2650,15 @@ static int dwc3_gadget_soft_disconnect(struct dwc3 *dwc)
      int ret;
 
      spin_lock_irqsave(&dwc->lock, flags);
+     /*
+      * Attempt to disconnect a no connected gadget
+      */
+     if (!dwc->connected) {
+             dev_warn(dwc->dev, "No connected device\n");
+             spin_unlock_irqrestore(&dwc->lock, flags);
+             return 0;
+     }
+
      dwc->connected = false;
 
      /*
--
Quoted 2 lines

2.40.1

There's already a fix for this, and it's already in mainline. Let me know if this works for you:

Quoted 2 lines

https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=b191a18cb5c47109ca696370a74a5062a70adfd0

Can you explain to me the logic here? I mean pullsup_connected seems never protected by spin lock and so I can not figure
out it easily and the commit message does not explain so much

Michael

Quoted 2 lines

Thanks,
Thinh

maintainer
#5 lore raw

Hi,

Quoted 105 lines · Michael Nazzareno Trimarchi

Hi

Quoted 102 lines · Thinh Nguyen

Hi,

Quoted 92 lines · Michael Trimarchi

This patch avoid to disconnect an already gadget in not connected state

[   45.597274] dwc3 31000000.usb: wait for SETUP phase timed out
[   45.599140] dwc3 31000000.usb: failed to set STALL on ep0out
[   45.601069] ------------[ cut here ]------------
[   45.601073] WARNING: CPU: 0 PID: 150 at drivers/usb/dwc3/ep0.c:289 dwc3_ep0_out_start+0xcc/0xd4
[   45.601102] Modules linked in: cfg80211 rfkill ipv6 rpmsg_ctrl rpmsg_char crct10dif_ce rti_wdt k3_j72xx_bandgap rtc_ti_k3 omap_mailbox sa2ul authenc [last unloaded: ti_k3_r5_remoteproc]
[   45.601151] CPU: 0 PID: 150 Comm: sh Not tainted 6.8.0-rc5 #1
[   45.601159] Hardware name: BSH - CCM-M3 (DT)
[   45.601164] pstate: 600000c5 (nZCv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[   45.601172] pc : dwc3_ep0_out_start+0xcc/0xd4
[   45.601179] lr : dwc3_ep0_out_start+0x50/0xd4
[   45.601186] sp : ffff8000832739e0
[   45.601189] x29: ffff8000832739e0 x28: ffff800082a21000 x27: ffff8000808dc630
[   45.601200] x26: 0000000000000002 x25: ffff800082530a44 x24: 0000000000000000
[   45.601210] x23: ffff000000e079a0 x22: ffff000000e07a68 x21: 0000000000000001
[   45.601219] x20: ffff000000e07880 x19: ffff000000e07880 x18: 0000000000000040
[   45.601229] x17: ffff7fff8e1ce000 x16: ffff800080000000 x15: fffffffffffe5260
[   45.601239] x14: 0000000000000000 x13: 206e6f204c4c4154 x12: 5320746573206f74
[   45.601249] x11: 0000000000000001 x10: 000000000000000a x9 : ffff800083273930
[   45.601259] x8 : 000000000000000a x7 : ffffffffffff3f0c x6 : ffffffffffff3f00
[   45.601268] x5 : ffffffffffff3f0c x4 : 0000000000000000 x3 : 0000000000000000
[   45.601278] x2 : 0000000000000000 x1 : ffff000004e7e600 x0 : 00000000ffffff92
[   45.601289] Call trace:
[   45.601293]  dwc3_ep0_out_start+0xcc/0xd4
[   45.601301]  dwc3_ep0_stall_and_restart+0x98/0xbc
[   45.601309]  dwc3_ep0_reset_state+0x5c/0x88
[   45.601315]  dwc3_gadget_soft_disconnect+0x144/0x160
[   45.601323]  dwc3_gadget_suspend+0x18/0xb0
[   45.601329]  dwc3_suspend_common+0x5c/0x18c
[   45.601341]  dwc3_suspend+0x20/0x44
[   45.601350]  platform_pm_suspend+0x2c/0x6c
[   45.601360]  __device_suspend+0x10c/0x34c
[   45.601372]  dpm_suspend+0x1a8/0x240
[   45.601382]  dpm_suspend_start+0x80/0x9c
[   45.601391]  suspend_devices_and_enter+0x1c4/0x584
[   45.601402]  pm_suspend+0x1b0/0x264
[   45.601408]  state_store+0x80/0xec
[   45.601415]  kobj_attr_store+0x18/0x2c
[   45.601426]  sysfs_kf_write+0x44/0x54
[   45.601434]  kernfs_fop_write_iter+0x120/0x1ec
[   45.601445]  vfs_write+0x23c/0x358
[   45.601458]  ksys_write+0x70/0x104
[   45.601467]  __arm64_sys_write+0x1c/0x28
[   45.601477]  invoke_syscall+0x48/0x114
[   45.601488]  el0_svc_common.constprop.0+0x40/0xe0
[   45.601498]  do_el0_svc+0x1c/0x28
[   45.601506]  el0_svc+0x34/0xb8
[   45.601516]  el0t_64_sync_handler+0x100/0x12c
[   45.601522]  el0t_64_sync+0x190/0x194
[   45.601531] ---[ end trace 0000000000000000 ]---
[   45.608794] Disabling non-boot CPUs ...
[   45.611029] psci: CPU1 killed (polled 0 ms)
[   45.611837] Enabling non-boot CPUs ...
[   45.612247] Detected VIPT I-cache on CPU1

Tested on a am62x board with a usbnet gadget

Fixes 61a348857e86 ("usb: dwc3: gadget: Fix NULL pointer dereference in dwc3_gadget_suspend)

---
V2->V3:
- Change the logic of the patch using the gadget connected state
- Change of the commit message
V1->V2:
- Add stable in CC

---
 drivers/usb/dwc3/gadget.c | 9 +++++++++
 1 file changed, 9 insertions(+)
drivers/usb/dwc3/gadget.c +9 -1
index 4c8dd6724678..a7316a1703ad 100644
@@ -2650,6 +2650,15 @@ static int dwc3_gadget_soft_disconnect(struct dwc3 *dwc)
      int ret;
 
      spin_lock_irqsave(&dwc->lock, flags);
+     /*
+      * Attempt to disconnect a no connected gadget
+      */
+     if (!dwc->connected) {
+             dev_warn(dwc->dev, "No connected device\n");
+             spin_unlock_irqrestore(&dwc->lock, flags);
+             return 0;
+     }
+
      dwc->connected = false;
 
      /*
--
Quoted 2 lines

2.40.1

There's already a fix for this, and it's already in mainline. Let me know if this works for you:

Quoted 7 lines
Quoted 2 lines

https://urldefense.com/v3/__https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=b191a18cb5c47109ca696370a74a5062a70adfd0__;!!A4F2R9G_pg!dqF-dGSHGR41Bep_7ZG2mWfPNYWfC4T-_FpOf_pFIvqa9L1n1e6l6D3oP9bOlRRFobW4Uvh0VAP8qBkLMfNkUlfaeTc$

Can you explain to me the logic here? I mean pullsup_connected seems never protected by spin lock and so I can not figure
out it easily and the commit message does not explain so much

Sorry for the delay response.

Ah.. you're right, the spin_lock isn't useful there. My intention was to avoid soft disconnect flow to occur during system suspend along with pullup(off). I somehow forgot that it isn't protected with spin_lock.

It's a very unlikely scenario. Even if it did happen, it should be harmless. But to solve that perhaps we can:
1) Keep the code simple and enforce no sleep and hold spin_lock during the entirety of run_stop() sequence
2) Enforce a must-lock check to run_stop() and unlock during sleep. This requires more code changes and reviews.

If you have some ideas, please share. (Note that using dwc->connected isn't sufficient)

Thanks,
Thinh

#6 lore raw

Hi

Quoted 117 lines · Thinh Nguyen

Hi,

Quoted 105 lines · Michael Nazzareno Trimarchi

Hi

Quoted 102 lines · Thinh Nguyen

Hi,

Quoted 92 lines · Michael Trimarchi

This patch avoid to disconnect an already gadget in not connected state

[   45.597274] dwc3 31000000.usb: wait for SETUP phase timed out
[   45.599140] dwc3 31000000.usb: failed to set STALL on ep0out
[   45.601069] ------------[ cut here ]------------
[   45.601073] WARNING: CPU: 0 PID: 150 at drivers/usb/dwc3/ep0.c:289 dwc3_ep0_out_start+0xcc/0xd4
[   45.601102] Modules linked in: cfg80211 rfkill ipv6 rpmsg_ctrl rpmsg_char crct10dif_ce rti_wdt k3_j72xx_bandgap rtc_ti_k3 omap_mailbox sa2ul authenc [last unloaded: ti_k3_r5_remoteproc]
[   45.601151] CPU: 0 PID: 150 Comm: sh Not tainted 6.8.0-rc5 #1
[   45.601159] Hardware name: BSH - CCM-M3 (DT)
[   45.601164] pstate: 600000c5 (nZCv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[   45.601172] pc : dwc3_ep0_out_start+0xcc/0xd4
[   45.601179] lr : dwc3_ep0_out_start+0x50/0xd4
[   45.601186] sp : ffff8000832739e0
[   45.601189] x29: ffff8000832739e0 x28: ffff800082a21000 x27: ffff8000808dc630
[   45.601200] x26: 0000000000000002 x25: ffff800082530a44 x24: 0000000000000000
[   45.601210] x23: ffff000000e079a0 x22: ffff000000e07a68 x21: 0000000000000001
[   45.601219] x20: ffff000000e07880 x19: ffff000000e07880 x18: 0000000000000040
[   45.601229] x17: ffff7fff8e1ce000 x16: ffff800080000000 x15: fffffffffffe5260
[   45.601239] x14: 0000000000000000 x13: 206e6f204c4c4154 x12: 5320746573206f74
[   45.601249] x11: 0000000000000001 x10: 000000000000000a x9 : ffff800083273930
[   45.601259] x8 : 000000000000000a x7 : ffffffffffff3f0c x6 : ffffffffffff3f00
[   45.601268] x5 : ffffffffffff3f0c x4 : 0000000000000000 x3 : 0000000000000000
[   45.601278] x2 : 0000000000000000 x1 : ffff000004e7e600 x0 : 00000000ffffff92
[   45.601289] Call trace:
[   45.601293]  dwc3_ep0_out_start+0xcc/0xd4
[   45.601301]  dwc3_ep0_stall_and_restart+0x98/0xbc
[   45.601309]  dwc3_ep0_reset_state+0x5c/0x88
[   45.601315]  dwc3_gadget_soft_disconnect+0x144/0x160
[   45.601323]  dwc3_gadget_suspend+0x18/0xb0
[   45.601329]  dwc3_suspend_common+0x5c/0x18c
[   45.601341]  dwc3_suspend+0x20/0x44
[   45.601350]  platform_pm_suspend+0x2c/0x6c
[   45.601360]  __device_suspend+0x10c/0x34c
[   45.601372]  dpm_suspend+0x1a8/0x240
[   45.601382]  dpm_suspend_start+0x80/0x9c
[   45.601391]  suspend_devices_and_enter+0x1c4/0x584
[   45.601402]  pm_suspend+0x1b0/0x264
[   45.601408]  state_store+0x80/0xec
[   45.601415]  kobj_attr_store+0x18/0x2c
[   45.601426]  sysfs_kf_write+0x44/0x54
[   45.601434]  kernfs_fop_write_iter+0x120/0x1ec
[   45.601445]  vfs_write+0x23c/0x358
[   45.601458]  ksys_write+0x70/0x104
[   45.601467]  __arm64_sys_write+0x1c/0x28
[   45.601477]  invoke_syscall+0x48/0x114
[   45.601488]  el0_svc_common.constprop.0+0x40/0xe0
[   45.601498]  do_el0_svc+0x1c/0x28
[   45.601506]  el0_svc+0x34/0xb8
[   45.601516]  el0t_64_sync_handler+0x100/0x12c
[   45.601522]  el0t_64_sync+0x190/0x194
[   45.601531] ---[ end trace 0000000000000000 ]---
[   45.608794] Disabling non-boot CPUs ...
[   45.611029] psci: CPU1 killed (polled 0 ms)
[   45.611837] Enabling non-boot CPUs ...
[   45.612247] Detected VIPT I-cache on CPU1

Tested on a am62x board with a usbnet gadget

Fixes 61a348857e86 ("usb: dwc3: gadget: Fix NULL pointer dereference in dwc3_gadget_suspend)

---
V2->V3:
- Change the logic of the patch using the gadget connected state
- Change of the commit message
V1->V2:
- Add stable in CC

---
 drivers/usb/dwc3/gadget.c | 9 +++++++++
 1 file changed, 9 insertions(+)
drivers/usb/dwc3/gadget.c +9 -1
index 4c8dd6724678..a7316a1703ad 100644
@@ -2650,6 +2650,15 @@ static int dwc3_gadget_soft_disconnect(struct dwc3 *dwc)
      int ret;
 
      spin_lock_irqsave(&dwc->lock, flags);
+     /*
+      * Attempt to disconnect a no connected gadget
+      */
+     if (!dwc->connected) {
+             dev_warn(dwc->dev, "No connected device\n");
+             spin_unlock_irqrestore(&dwc->lock, flags);
+             return 0;
+     }
+
      dwc->connected = false;
 
      /*
--
Quoted 2 lines

2.40.1

There's already a fix for this, and it's already in mainline. Let me know if this works for you:

Quoted 7 lines
Quoted 2 lines

https://urldefense.com/v3/__https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=b191a18cb5c47109ca696370a74a5062a70adfd0__;!!A4F2R9G_pg!dqF-dGSHGR41Bep_7ZG2mWfPNYWfC4T-_FpOf_pFIvqa9L1n1e6l6D3oP9bOlRRFobW4Uvh0VAP8qBkLMfNkUlfaeTc$

Can you explain to me the logic here? I mean pullsup_connected seems never protected by spin lock and so I can not figure
out it easily and the commit message does not explain so much

Quoted 6 lines

Sorry for the delay response.

Ah.. you're right, the spin_lock isn't useful there. My intention was to avoid soft disconnect flow to occur during system suspend along with pullup(off). I somehow forgot that it isn't protected with spin_lock.

You reduce the window of failure but we need to rework anyway

Quoted 4 lines

It's a very unlikely scenario. Even if it did happen, it should be harmless. But to solve that perhaps we can:
1) Keep the code simple and enforce no sleep and hold spin_lock during the entirety of run_stop() sequence

If the run_stop is executing I can imagine that you only need to mark it as ongoing and protect with a spin_lock, returning -EINVAL on the suspend hook. I will keep
it simple

Michael

Quoted 8 lines

2) Enforce a must-lock check to run_stop() and unlock during sleep. This requires more code changes and reviews.

If you have some ideas, please share. (Note that using dwc->connected isn't sufficient)

Thanks,
Thinh

Signature · 11 lines
Michael Nazzareno Trimarchi
Co-Founder & Chief Executive Officer
M. +39 347 913 2170
[email protected]
__________________________________

Amarula Solutions BV
Joop Geesinkweg 125, 1114 AB, Amsterdam, NL
T. +31 (0)85 111 9172
[email protected]
www.amarulasolutions.com