On Tue, Nov 11, 2014 at 09:03:26PM -0800, Dexuan Cui wrote: > In the case the user-space daemon crashes, hangs or is killed, we > need to down the semaphore, otherwise, after the daemon starts next > time, the obsolete data in fcopy_transaction.message or > fcopy_transaction.fcopy_msg will be used immediately. > > Cc: K. Y. Srinivasan <kys@xxxxxxxxxxxxx> > Signed-off-by: Dexuan Cui <decui@xxxxxxxxxxxxx> > --- > drivers/hv/hv_fcopy.c | 9 +++++++++ > 1 file changed, 9 insertions(+) > > diff --git a/drivers/hv/hv_fcopy.c b/drivers/hv/hv_fcopy.c > index 23b2ce2..177122a 100644 > --- a/drivers/hv/hv_fcopy.c > +++ b/drivers/hv/hv_fcopy.c > @@ -86,6 +86,15 @@ static void fcopy_work_func(struct work_struct *dummy) > * process the pending transaction. > */ > fcopy_respond_to_host(HV_E_FAIL); > + > + /* In the case the user-space daemon crashes, hangs or is killed, we > + * need to down the semaphore, otherwise, after the daemon starts next > + * time, the obsolete data in fcopy_transaction.message or > + * fcopy_transaction.fcopy_msg will be used immediately. > + */ > + if (down_trylock(&fcopy_transaction.read_sema)) > + pr_debug("FCP: failed to acquire the semaphore\n"); Why is "FCP:" needed? pr_debug() should never need any type of prefix. Please fix. thanks, greg k-h _______________________________________________ devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxx http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel