| Message ID | 20210628230051.556099-1-toke@redhat.com (mailing list archive) |
|---|---|
| State | Changes Requested |
| Delegated to: | BPF |
| Headers | show |
| Series | [bpf-next] bpf/devmap: convert remaining READ_ONCE() to rcu_dereference() | expand |
| Context | Check | Description |
|---|---|---|
| netdev/cover_letter | success | Link |
| netdev/fixes_present | success | Link |
| netdev/patch_count | success | Link |
| netdev/tree_selection | success | Clearly marked for bpf-next |
| netdev/subject_prefix | success | Link |
| netdev/cc_maintainers | fail | 1 blamed authors not CCed: daniel@iogearbox.net; 9 maintainers not CCed: yhs@fb.com kpsingh@kernel.org daniel@iogearbox.net andrii@kernel.org hawk@kernel.org ast@kernel.org john.fastabend@gmail.com songliubraving@fb.com davem@davemloft.net |
| netdev/source_inline | success | Was 0 now: 0 |
| netdev/verify_signedoff | success | Link |
| netdev/module_param | success | Was 0 now: 0 |
| netdev/build_32bit | success | Errors and warnings before: 3 this patch: 1 |
| netdev/kdoc | success | Errors and warnings before: 0 this patch: 0 |
| netdev/verify_fixes | success | Link |
| netdev/checkpatch | success | total: 0 errors, 0 warnings, 0 checks, 16 lines checked |
| netdev/build_allmodconfig_warn | success | Errors and warnings before: 3 this patch: 1 |
| netdev/header_inline | success | Link |
On Tue, Jun 29, 2021 at 01:00:51AM +0200, Toke Høiland-Jørgensen wrote: > There were a couple of READ_ONCE()-invocations left-over by the devmap RCU > conversion. Convert these to rcu_dereference() as well to avoid complaints > from sparse. > > Fixes: 782347b6bcad ("xdp: Add proper __rcu annotations to redirect map entries") > Reported-by: kernel test robot <lkp@intel.com> > Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com> Reviewed-by: Paul E. McKenney <paulmck@kernel.org> > --- > kernel/bpf/devmap.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/kernel/bpf/devmap.c b/kernel/bpf/devmap.c > index 2f6bd75cd682..7a0c008f751b 100644 > --- a/kernel/bpf/devmap.c > +++ b/kernel/bpf/devmap.c > @@ -558,7 +558,7 @@ int dev_map_enqueue_multi(struct xdp_buff *xdp, struct net_device *dev_rx, > > if (map->map_type == BPF_MAP_TYPE_DEVMAP) { > for (i = 0; i < map->max_entries; i++) { > - dst = READ_ONCE(dtab->netdev_map[i]); > + dst = rcu_dereference(dtab->netdev_map[i]); > if (!is_valid_dst(dst, xdp, exclude_ifindex)) > continue; > > @@ -654,7 +654,7 @@ int dev_map_redirect_multi(struct net_device *dev, struct sk_buff *skb, > > if (map->map_type == BPF_MAP_TYPE_DEVMAP) { > for (i = 0; i < map->max_entries; i++) { > - dst = READ_ONCE(dtab->netdev_map[i]); > + dst = rcu_dereference(dtab->netdev_map[i]); > if (!dst || dst->dev->ifindex == exclude_ifindex) > continue; > > -- > 2.32.0 >
On Tue, Jun 29, 2021 at 01:00:51AM +0200, Toke Høiland-Jørgensen wrote: > There were a couple of READ_ONCE()-invocations left-over by the devmap RCU > conversion. Convert these to rcu_dereference() as well to avoid complaints > from sparse. > > Fixes: 782347b6bcad ("xdp: Add proper __rcu annotations to redirect map entries") > Reported-by: kernel test robot <lkp@intel.com> > Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com> > --- > kernel/bpf/devmap.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/kernel/bpf/devmap.c b/kernel/bpf/devmap.c > index 2f6bd75cd682..7a0c008f751b 100644 > --- a/kernel/bpf/devmap.c > +++ b/kernel/bpf/devmap.c > @@ -558,7 +558,7 @@ int dev_map_enqueue_multi(struct xdp_buff *xdp, struct net_device *dev_rx, > > if (map->map_type == BPF_MAP_TYPE_DEVMAP) { > for (i = 0; i < map->max_entries; i++) { > - dst = READ_ONCE(dtab->netdev_map[i]); > + dst = rcu_dereference(dtab->netdev_map[i]); __dev_map_lookup_elem() uses rcu_dereference_check(dtab->netdev_map[key], rcu_read_lock_bh_held()). It is not needed here?
Martin KaFai Lau <kafai@fb.com> writes: > On Tue, Jun 29, 2021 at 01:00:51AM +0200, Toke Høiland-Jørgensen wrote: >> There were a couple of READ_ONCE()-invocations left-over by the devmap RCU >> conversion. Convert these to rcu_dereference() as well to avoid complaints >> from sparse. >> >> Fixes: 782347b6bcad ("xdp: Add proper __rcu annotations to redirect map entries") >> Reported-by: kernel test robot <lkp@intel.com> >> Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com> >> --- >> kernel/bpf/devmap.c | 4 ++-- >> 1 file changed, 2 insertions(+), 2 deletions(-) >> >> diff --git a/kernel/bpf/devmap.c b/kernel/bpf/devmap.c >> index 2f6bd75cd682..7a0c008f751b 100644 >> --- a/kernel/bpf/devmap.c >> +++ b/kernel/bpf/devmap.c >> @@ -558,7 +558,7 @@ int dev_map_enqueue_multi(struct xdp_buff *xdp, struct net_device *dev_rx, >> >> if (map->map_type == BPF_MAP_TYPE_DEVMAP) { >> for (i = 0; i < map->max_entries; i++) { >> - dst = READ_ONCE(dtab->netdev_map[i]); >> + dst = rcu_dereference(dtab->netdev_map[i]); > __dev_map_lookup_elem() uses rcu_dereference_check(dtab->netdev_map[key], rcu_read_lock_bh_held()). > It is not needed here? Hmm, I somehow managed to convince myself last night that it wasn't, but looking at it again now I think you're right. Will send a v2. -Toke
diff --git a/kernel/bpf/devmap.c b/kernel/bpf/devmap.c index 2f6bd75cd682..7a0c008f751b 100644 --- a/kernel/bpf/devmap.c +++ b/kernel/bpf/devmap.c @@ -558,7 +558,7 @@ int dev_map_enqueue_multi(struct xdp_buff *xdp, struct net_device *dev_rx, if (map->map_type == BPF_MAP_TYPE_DEVMAP) { for (i = 0; i < map->max_entries; i++) { - dst = READ_ONCE(dtab->netdev_map[i]); + dst = rcu_dereference(dtab->netdev_map[i]); if (!is_valid_dst(dst, xdp, exclude_ifindex)) continue; @@ -654,7 +654,7 @@ int dev_map_redirect_multi(struct net_device *dev, struct sk_buff *skb, if (map->map_type == BPF_MAP_TYPE_DEVMAP) { for (i = 0; i < map->max_entries; i++) { - dst = READ_ONCE(dtab->netdev_map[i]); + dst = rcu_dereference(dtab->netdev_map[i]); if (!dst || dst->dev->ifindex == exclude_ifindex) continue;
There were a couple of READ_ONCE()-invocations left-over by the devmap RCU conversion. Convert these to rcu_dereference() as well to avoid complaints from sparse. Fixes: 782347b6bcad ("xdp: Add proper __rcu annotations to redirect map entries") Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com> --- kernel/bpf/devmap.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)