This is a note to let you know that I've just added the patch titled
usb: dwc3: omap: fix race of pm runtime with irq handler in probe
to the 4.9-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
usb-dwc3-omap-fix-race-of-pm-runtime-with-irq-handler-in-probe.patch
and it can be found in the queue-4.9 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From foo@baz Fri Aug 4 15:15:01 PDT 2017
From: Grygorii Strashko <grygorii.strashko@xxxxxx>
Date: Mon, 12 Dec 2016 13:37:52 -0600
Subject: usb: dwc3: omap: fix race of pm runtime with irq handler in probe
From: Grygorii Strashko <grygorii.strashko@xxxxxx>
[ Upstream commit 12a7f17fac5b370bec87259e4c718faf563ce900 ]
Now races can happen between interrupt handler execution and PM runtime in
error handling code path in probe and in dwc3_omap_remove() which will lead
to system crash:
in probe:
...
err1:
pm_runtime_put_sync(dev);
^^ PM runtime can race with IRQ handler when deferred probing happening
due to extcon
pm_runtime_disable(dev);
return ret;
in dwc3_omap_remove:
...
dwc3_omap_disable_irqs(omap);
^^ IRQs are disabled in HW, but handler may still run
of_platform_depopulate(omap->dev);
pm_runtime_put_sync(&pdev->dev);
^^ PM runtime can race with IRQ handler
pm_runtime_disable(&pdev->dev);
return 0;
So, OMAP DWC3 IRQ need to be disabled before calling
pm_runtime_put() in probe and in dwc3_omap_remove().
Acked-by: Tony Lindgren <tony@xxxxxxxxxxx>
Signed-off-by: Grygorii Strashko <grygorii.strashko@xxxxxx>
Signed-off-by: Felipe Balbi <felipe.balbi@xxxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/usb/dwc3/dwc3-omap.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)
--- a/drivers/usb/dwc3/dwc3-omap.c
+++ b/drivers/usb/dwc3/dwc3-omap.c
@@ -19,6 +19,7 @@
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/slab.h>
+#include <linux/irq.h>
#include <linux/interrupt.h>
#include <linux/platform_device.h>
#include <linux/platform_data/dwc3-omap.h>
@@ -511,7 +512,7 @@ static int dwc3_omap_probe(struct platfo
/* check the DMA Status */
reg = dwc3_omap_readl(omap->base, USBOTGSS_SYSCONFIG);
-
+ irq_set_status_flags(omap->irq, IRQ_NOAUTOEN);
ret = devm_request_threaded_irq(dev, omap->irq, dwc3_omap_interrupt,
dwc3_omap_interrupt_thread, IRQF_SHARED,
"dwc3-omap", omap);
@@ -532,7 +533,7 @@ static int dwc3_omap_probe(struct platfo
}
dwc3_omap_enable_irqs(omap);
-
+ enable_irq(omap->irq);
return 0;
err2:
@@ -553,6 +554,7 @@ static int dwc3_omap_remove(struct platf
extcon_unregister_notifier(omap->edev, EXTCON_USB, &omap->vbus_nb);
extcon_unregister_notifier(omap->edev, EXTCON_USB_HOST, &omap->id_nb);
dwc3_omap_disable_irqs(omap);
+ disable_irq(omap->irq);
of_platform_depopulate(omap->dev);
pm_runtime_put_sync(&pdev->dev);
pm_runtime_disable(&pdev->dev);
Patches currently in stable-queue which might be from grygorii.strashko@xxxxxx are
queue-4.9/usb-dwc3-omap-fix-race-of-pm-runtime-with-irq-handler-in-probe.patch
queue-4.9/irqchip-keystone-fix-scheduling-while-atomic-on-rt.patch