On Tue, 2013-04-23 at 12:29 -0400, Rik van Riel wrote: > Andrew, here is the patch I promised :) > > Everywhere else in the code, we check sma->sem_perm.deleted under > the semaphore array lock, so we should do teh same here. > The easy fix is to simply not drop and re-take the lock, but keep > it locked. >
CCing Linus, Sedat and Emmanuel. This looks very much like a patch I asked Sedat to test during the weekend, which according to him didn't solve his issue. The patch is correct in any case. > This patch can be folded into ipcsem-fine-grained-locking-for-semtimedop.patch > > Signed-off-by: Rik van Riel <[email protected]> Acked-by: Davidlohr Bueso <[email protected]> > --- > ipc/sem.c | 5 ++--- > 1 file changed, 2 insertions(+), 3 deletions(-) > > diff --git a/ipc/sem.c b/ipc/sem.c > index 5711616..efdaee6 100644 > --- a/ipc/sem.c > +++ b/ipc/sem.c > @@ -1243,10 +1243,9 @@ static int semctl_main(struct ipc_namespace *ns, int > semid, int semnum, > err = -EIDRM; > goto out_free; > } > - sem_unlock(sma, -1); > - } > + } else > + sem_lock(sma, NULL, -1); > > - sem_lock(sma, NULL, -1); > for (i = 0; i < sma->sem_nsems; i++) > sem_io[i] = sma->sem_base[i].semval; > sem_unlock(sma, -1); -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
