On Mon, 15 Apr 2019, Andrey Konovalov wrote:
> On Mon, Apr 15, 2019 at 5:16 PM Andrey Konovalov <andreyknvl@xxxxxxxxxx> wrote:
> >
> > On Mon, Apr 15, 2019 at 2:34 PM syzbot
> > <syzbot+7634edaea4d0b341c625@xxxxxxxxxxxxxxxxxxxxxxxxx> wrote:
> > >
> > > Hello,
> > >
> > > syzbot has tested the proposed patch and the reproducer did not trigger
> > > crash:
> > >
> > > Reported-and-tested-by:
> > > syzbot+7634edaea4d0b341c625@xxxxxxxxxxxxxxxxxxxxxxxxx
> >
> > Hm, I think this is some kind of race and the patch affects the
> > timings, so this can't be reproduced that easily. I'll try to do it
> > manually.
>
> Hm, now I'm having troubles to reproduce it manually. Let's try your
> debug patch once more on the exact commit this was reported. If it
> doesn't trigger, I think the best thing would be to close this report
> as invalid, and wait for syzbot to (hopefully) generate a fresh
> reproducer.
>
> #syz test: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
> e12e00e388de
Okay, let's try a simpler and less intrusive debugging patch.
Alan Stern
#syz test: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git e12e00e388de
--- a/drivers/usb/core/hub.c
+++ b/drivers/usb/core/hub.c
@@ -1016,6 +1016,8 @@ static void hub_activate(struct usb_hub
bool need_debounce_delay = false;
unsigned delay;
+ dev_info(hub->intfdev, "%s type %d\n", __func__, type);
+
/* Continue a partial initialization */
if (type == HUB_INIT2 || type == HUB_INIT3) {
device_lock(&hdev->dev);
@@ -1254,6 +1256,7 @@ static void hub_activate(struct usb_hub
init3:
hub->quiescing = 0;
+ dev_info(hub->intfdev, "Submitting status URB\n");
status = usb_submit_urb(hub->urb, GFP_NOIO);
if (status < 0)
dev_err(hub->intfdev, "activate --> %d\n", status);
@@ -3711,7 +3714,7 @@ static int hub_suspend(struct usb_interf
}
}
- dev_dbg(&intf->dev, "%s\n", __func__);
+ dev_info(&intf->dev, "%s\n", __func__);
/* stop hub_wq and related activity */
hub_quiesce(hub, HUB_SUSPEND);
@@ -3756,7 +3759,7 @@ static int hub_resume(struct usb_interfa
{
struct usb_hub *hub = usb_get_intfdata(intf);
- dev_dbg(&intf->dev, "%s\n", __func__);
+ dev_info(&intf->dev, "%s\n", __func__);
hub_activate(hub, HUB_RESUME);
/*
