| Message ID | 1377774651-5394-1-git-send-email-james.hogan@imgtec.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Quoting James Hogan (2013-08-29 04:10:51) > Commit 71472c0 (clk: add support for clock reparent on set_rate) added a > dereference of the new_parent pointer in clk_reparent(), but as detected > by smatch clk_reparent() later checks whether new_parent is NULL. > > The dereference was in order to clear the new parent's new_child pointer > to avoid duplicate POST_RATE_CHANGE notifications, so clearly isn't > necessary if the new parent is NULL, so move it inside the "if > (new_parent)" block. > > Reported-by: Dan Carpenter <dan.carpenter@oracle.com> > Signed-off-by: James Hogan <james.hogan@imgtec.com> > Cc: Mike Turquette <mturquette@linaro.org> > Cc: linux-arm-kernel@lists.infradead.org Thanks for the quick fix. I've pulled this into clk-next. Regards, Mike > --- > drivers/clk/clk.c | 13 +++++++------ > 1 file changed, 7 insertions(+), 6 deletions(-) > > diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c > index 2db08c0..02e75d4 100644 > --- a/drivers/clk/clk.c > +++ b/drivers/clk/clk.c > @@ -1108,16 +1108,17 @@ static u8 clk_fetch_parent_index(struct clk *clk, struct clk *parent) > > static void clk_reparent(struct clk *clk, struct clk *new_parent) > { > - /* avoid duplicate POST_RATE_CHANGE notifications */ > - if (new_parent->new_child == clk) > - new_parent->new_child = NULL; > - > hlist_del(&clk->child_node); > > - if (new_parent) > + if (new_parent) { > + /* avoid duplicate POST_RATE_CHANGE notifications */ > + if (new_parent->new_child == clk) > + new_parent->new_child = NULL; > + > hlist_add_head(&clk->child_node, &new_parent->children); > - else > + } else { > hlist_add_head(&clk->child_node, &clk_orphan_list); > + } > > clk->parent = new_parent; > } > -- > 1.8.1.2
diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c index 2db08c0..02e75d4 100644 --- a/drivers/clk/clk.c +++ b/drivers/clk/clk.c @@ -1108,16 +1108,17 @@ static u8 clk_fetch_parent_index(struct clk *clk, struct clk *parent) static void clk_reparent(struct clk *clk, struct clk *new_parent) { - /* avoid duplicate POST_RATE_CHANGE notifications */ - if (new_parent->new_child == clk) - new_parent->new_child = NULL; - hlist_del(&clk->child_node); - if (new_parent) + if (new_parent) { + /* avoid duplicate POST_RATE_CHANGE notifications */ + if (new_parent->new_child == clk) + new_parent->new_child = NULL; + hlist_add_head(&clk->child_node, &new_parent->children); - else + } else { hlist_add_head(&clk->child_node, &clk_orphan_list); + } clk->parent = new_parent; }
Commit 71472c0 (clk: add support for clock reparent on set_rate) added a dereference of the new_parent pointer in clk_reparent(), but as detected by smatch clk_reparent() later checks whether new_parent is NULL. The dereference was in order to clear the new parent's new_child pointer to avoid duplicate POST_RATE_CHANGE notifications, so clearly isn't necessary if the new parent is NULL, so move it inside the "if (new_parent)" block. Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Mike Turquette <mturquette@linaro.org> Cc: linux-arm-kernel@lists.infradead.org --- drivers/clk/clk.c | 13 +++++++------ 1 file changed, 7 insertions(+), 6 deletions(-)