]> www.infradead.org Git - users/jedix/linux-maple.git/commit
usb: dwc3: Skip resume if pm_runtime_set_active() fails
authorRay Chi <raychi@google.com>
Mon, 6 Jan 2025 08:22:37 +0000 (16:22 +0800)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Sat, 11 Jan 2025 16:02:30 +0000 (17:02 +0100)
commite3a9bd247cddfb6fa0c29c2361f70b76c359eaa0
tree7e81bd42d6f68004989b0d3a0ca0156c5f7631f5
parenta181c8ef0b745cdb61151c710f0880d00b8442b7
usb: dwc3: Skip resume if pm_runtime_set_active() fails

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