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charset="UTF-8" User-Agent: Evolution 3.52.3-0ubuntu1 Precedence: bulk X-Mailing-List: mptcp@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Hi Matt, Thanks for this fix. On Thu, 2024-10-17 at 12:16 +0200, Matthieu Baerts (NGI0) wrote: > mptcp_get_available_schedulers() needs to iterate over the > schedulers' > list only to read the names: it doesn't modify anything there. > > In this case, it is enough to hold the RCU read lock, no need to > combine > this with the associated spin lock. > > Fixes: 73c900aa3660 ("mptcp: add net.mptcp.available_schedulers") > Suggested-by: Paolo Abeni > Signed-off-by: Matthieu Baerts (NGI0) Good catch! Reviewed-by: Geliang Tang -Geliang > --- >  net/mptcp/sched.c | 2 -- >  1 file changed, 2 deletions(-) > > diff --git a/net/mptcp/sched.c b/net/mptcp/sched.c > index > 5257bc6c8cd6e8ca674c9beccaf7b27c989da76a..6da60e35932ffd8a92ad7a8b128 > e5eaf09219b82 100644 > --- a/net/mptcp/sched.c > +++ b/net/mptcp/sched.c > @@ -60,7 +60,6 @@ void mptcp_get_available_schedulers(char *buf, > size_t maxlen) >   size_t offs = 0; >   >   rcu_read_lock(); > - spin_lock(&mptcp_sched_list_lock); >   list_for_each_entry_rcu(sched, &mptcp_sched_list, list) { >   offs += snprintf(buf + offs, maxlen - offs, >   "%s%s", > @@ -69,7 +68,6 @@ void mptcp_get_available_schedulers(char *buf, > size_t maxlen) >   if (WARN_ON_ONCE(offs >= maxlen)) >   break; >   } > - spin_unlock(&mptcp_sched_list_lock); >   rcu_read_unlock(); >  } >   >