6.12-stable review patch. If anyone has any objections, please let me know.
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From: Ray Chi raychi@google.com
commit e3a9bd247cddfb6fa0c29c2361f70b76c359eaa0 upstream.
When the system begins to enter suspend mode, dwc3_suspend() is called by PM suspend. There is a problem that if someone interrupt the system suspend process between dwc3_suspend() and pm_suspend() of its parent device, PM suspend will be canceled and attempt to resume suspended devices so that dwc3_resume() will be called. However, dwc3 and its parent device (like the power domain or glue driver) may already be suspended by runtime PM in fact. If this sutiation happened, the pm_runtime_set_active() in dwc3_resume() will return an error since parent device was suspended. This can lead to unexpected behavior if DWC3 proceeds to execute dwc3_resume_common().
EX. RPM suspend: ... -> dwc3_runtime_suspend() -> rpm_suspend() of parent device ... PM suspend: ... -> dwc3_suspend() -> pm_suspend of parent device ^ interrupt, so resume suspended device ... <- dwc3_resume() <-/ ^ pm_runtime_set_active() returns error
To prevent the problem, this commit will skip dwc3_resume_common() and return the error if pm_runtime_set_active() fails.
Fixes: 68c26fe58182 ("usb: dwc3: set pm runtime active before resume common") Cc: stable stable@kernel.org Signed-off-by: Ray Chi raychi@google.com Acked-by: Thinh Nguyen Thinh.Nguyen@synopsys.com Link: https://lore.kernel.org/r/20250106082240.3822059-1-raychi@google.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/usb/dwc3/core.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-)
--- a/drivers/usb/dwc3/core.c +++ b/drivers/usb/dwc3/core.c @@ -2597,12 +2597,15 @@ static int dwc3_resume(struct device *de pinctrl_pm_select_default_state(dev);
pm_runtime_disable(dev); - pm_runtime_set_active(dev); + ret = pm_runtime_set_active(dev); + if (ret) + goto out;
ret = dwc3_resume_common(dwc, PMSG_RESUME); if (ret) pm_runtime_set_suspended(dev);
+out: pm_runtime_enable(dev);
return ret;