Re: [PATCH stable 5.10] usb: dwc3: Remove DWC3 locking during gadget suspend/resume

[Greg KH <gregkh@linuxfoundation.org>]

On Wed, Aug 20, 2025 at 07:41:44PM +0530, Selvarasu Ganesan wrote:
> Dear stable team,
> 
> 
> Patch : usb: dwc3: Remove DWC3 locking during gadget suspend/resume
> 
> Commit id:5265397f94424eaea596026fd34dc7acf474dcec
> 
> This patch fixes a critical bug in the dwc3 driver that was introduced 
> by commit 
> (https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/drivers/usb/dwc3/gadget.c?h=v5.10.240&id=90e2820c6c30db2427d020d344dfca7de813bd24 
> <https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/drivers/usb/dwc3/gadget.c?h=v5.10.240&id=90e2820c6c30db2427d020d344dfca7de813bd24>) 
> in the 5.10 kernel series.

But that is not what the dwc3 patch says it does, how do we know it is
ok to backport this?

> The bug causes the below kernel crash (Added usleep in atomic context as 
> part of above patch) under dwc3 suspend/resume scenarios.
> 
> 35.829644] [6: kworker/6:1: 68] BUG: scheduling while atomic: 
> kworker/6:1/68/0x00000002
> 
> [ 35.829946] [6: kworker/6:1: 68] CPU: 6 PID: 68 Comm: kworker/6:1 
> Tainted: G C E 5.10.236-android13-4 #1
> 
> [ 35.830010] [6: kworker/6:1: 68] Call trace:
> 
> [ 35.830024] [6: kworker/6:1: 68] dump_backtrace.cfi_jt+0x0/0x8
> 
> [ 35.830034] [6: kworker/6:1: 68] show_stack+0x1c/0x2c
> 
> [ 35.830044] [6: kworker/6:1: 68] dump_stack_lvl+0xd8/0x134
> 
> [ 35.830053] [6: kworker/6:1: 68] __schedule_bug+0x80/0xbc
> 
> [ 35.830062] [6: kworker/6:1: 68] __schedule+0x55c/0x7e8
> 
> [ 35.830068] [6: kworker/6:1: 68] schedule+0x80/0x100
> 
> [ 35.830077] [6: kworker/6:1: 68] schedule_hrtimeout_range_clock+0xa8/0x11c
> 
> [ 35.830083] [6: kworker/6:1: 68] usleep_range+0x68/0xa4
> 
> [ 35.830093] [6: kworker/6:1: 68] dwc3_gadget_run_stop+0x170/0x448
> 
> [ 35.830099] [6: kworker/6:1: 68] dwc3_gadget_resume+0x4c/0xdc
> 
> [ 35.830108] [6: kworker/6:1: 68] dwc3_resume_common+0x6c/0x23c
> 
> [ 35.830115] [6: kworker/6:1: 68] dwc3_runtime_resume+0x40/0xcc
> 
> [ 35.830123] [6: kworker/6:1: 68] pm_generic_runtime_resume+0x48/0x88
> 
> [ 35.830131] [6: kworker/6:1: 68] __rpm_callback+0x94/0x420
> 
> The patch(5265397f9442) for this fix was originally merged in the below 
> commit:
> 
> https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/commit/drivers/usb/dwc3?h=next-20250820&id=5265397f94424eaea596026fd34dc7acf474dcec 
> <https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/commit/drivers/usb/dwc3?h=next-20250820&id=5265397f94424eaea596026fd34dc7acf474dcec>
> 
>   Please apply this patch to the stable 5.10 kernel to prevent this BUG.
> 
> Additionally the below patch also required to avoid dead lock that 
> introduced by the abovepatch (5265397f9442) in 5.10 stable kernel.
> 
> Patch:usb: dwc3: core: remove lock of otg mode during gadget 
> suspend/resume to avoid deadlock
> 
> Commit id:7838de15bb700c2898a7d741db9b1f3cbc86c136

Can you please submit a backported, and tested, series of patches here
so that we know that we got the correct ones, and we have your
signed-off-by on them to show you tested them?

thanks,

greg k-h