________________________________________ From: linux-usb-owner@xxxxxxxxxxxxxxx [linux-usb-owner@xxxxxxxxxxxxxxx] On Behalf Of Gupta, Ajay Kumar [ajay.gupta@xxxxxx] Sent: Friday, August 22, 2008 8:44 PM To: Alan Stern Cc: linux-omap@xxxxxxxxxxxxxxx; linux-usb@xxxxxxxxxxxxxxx; felipe.balbi@xxxxxxxxx; ajaykuee@xxxxxxxxx Subject: RE: [PATCH] OMAP:MUSB: Corrects urb unlink function path On Fri, 22 Aug 2008 ajay.gupta@xxxxxx wrote: > From: Ajay Kumar Gupta <ajay.gupta@xxxxxx> > > Fixes kernel panic while ISO IN transfer is aborted.Replaced usb_hcd_unlink_urb_from_ep() from musb_giveback() to __musb_giveback() to make sure urb is unlinked before giveback when __musb_giveback() is called from musb_urb_dequeue(). > > Signed-off-by: Ajay Kumar Gupta <ajay.gupta@xxxxxx> > --- > drivers/usb/musb/musb_host.c | 3 +-- > 1 files changed, 1 insertions(+), 2 deletions(-) > > diff --git a/drivers/usb/musb/musb_host.c b/drivers/usb/musb/musb_host.c > index 93b0678..a889ac4 100644 > --- a/drivers/usb/musb/musb_host.c > +++ b/drivers/usb/musb/musb_host.c > @@ -292,6 +292,7 @@ __acquires(musb->lock) > ); > > spin_unlock(&musb->lock); > + usb_hcd_unlink_urb_from_ep(musb_to_hcd(musb), urb); > usb_hcd_giveback_urb(musb_to_hcd(musb), urb, status); > spin_lock(&musb->lock); >This is wrong. You must call usb_hcd_unlink_urb_from_ep() while >holding musb->lock. > >You are correct. the unlink function should be moved above spin_unlock(). as, > >+ usb_hcd_unlink_urb_from_ep(musb_to_hcd(musb), urb); > spin_unlock(&musb->lock); > usb_hcd_giveback_urb(musb_to_hcd(musb), urb, status); > spin_lock(&musb->lock); >Simiar locking issue is also in enqueue path where unlink is being done >without holding musb->lock. I will resend the patch with other lock fixes. Ajay >Alan Stern-- >To unsubscribe from this list: send the line "unsubscribe linux-usb" in >the body of a message to majordomo@xxxxxxxxxxxxxxx >More majordomo info at http://vger.kernel.org/majordomo-info.html-- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
