> -----Original Message----- > From: Dexuan Cui [mailto:decui@xxxxxxxxxxxxx] > Sent: Wednesday, July 16, 2014 12:01 AM > To: gregkh@xxxxxxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; driverdev- > devel@xxxxxxxxxxxxxxxxxxxxxx; olaf@xxxxxxxxx; apw@xxxxxxxxxxxxx; > jasowang@xxxxxxxxxx > Cc: KY Srinivasan; Haiyang Zhang > Subject: [PATCH] Drivers: hv: hv_fcopy: fix a race condition for SMP guest > > We should schedule the 5s "timer work" before starting the data transfer, > otherwise, the data transfer code may finish so fast on another virtual cpu > that when the code(fcopy_write()) trying to cancel the 5s "timer work" can > occasionally fail because the "timer work" may haven't been scheduled yet > and as a result the fcopy process will be aborted wrongly by > fcopy_work_func() in 5s. > > Thank Liz Zhang <lizzha@xxxxxxxxxxxxx> for the initial investigation on the > bug. > > This addresses https://bugzilla.redhat.com/show_bug.cgi?id=1118123 > > Tested-by: Liz Zhang <lizzha@xxxxxxxxxxxxx> > Cc: K. Y. Srinivasan <kys@xxxxxxxxxxxxx> > Cc: Haiyang Zhang <haiyangz@xxxxxxxxxxxxx> > Cc: stable@xxxxxxxxxxxxxxx > Signed-off-by: Dexuan Cui <decui@xxxxxxxxxxxxx> Thanks Dexuan. Signed-off-by: K. Y. Srinivasan <kys@xxxxxxxxxxxxx> K. Y > --- > drivers/hv/hv_fcopy.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/hv/hv_fcopy.c b/drivers/hv/hv_fcopy.c index > eaaa3d8..23b2ce2 100644 > --- a/drivers/hv/hv_fcopy.c > +++ b/drivers/hv/hv_fcopy.c > @@ -246,8 +246,8 @@ void hv_fcopy_onchannelcallback(void *context) > /* > * Send the information to the user-level daemon. > */ > - fcopy_send_data(); > schedule_delayed_work(&fcopy_work, 5*HZ); > + fcopy_send_data(); > return; > } > icmsghdr->icflags = ICMSGHDRFLAG_TRANSACTION | > ICMSGHDRFLAG_RESPONSE; > -- > 1.9.1 _______________________________________________ devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxx http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel
