| Message ID | 1341313938-17861-1-git-send-email-rnayak@ti.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Tuesday 03 July 2012 04:42 PM, Rajendra Nayak wrote: > The below commit introduced a bug in __clk_set_parent() > which could cause it to *skip* the parent validation > which makes sure the parent passed to the api is a valid > one. Need this fix for Tegra too. > commit 7975059db572eb47f0fb272a62afeae272a4b209 > Author: Rajendra Nayak<rnayak@ti.com> > Date: Wed Jun 6 14:41:31 2012 +0530 > > clk: Allow late cache allocation for clk->parents > > This was identified by the following compiler warning.. > > drivers/clk/clk.c: In function '__clk_set_parent': > drivers/clk/clk.c:1083:5: warning: 'i' may be used uninitialized in this function [-Wuninitialized] > > .. as reported by Marc Kleine-Budde. > > There were various options discussed on how to fix this, one > being initing 'i' to clk->num_parents, but the below approach > was found to be more appropriate as it also makes the 'parent > validation' code simpler to read. > > Reported-by: Marc Kleine-Budde<mkl@pengutronix.de> > Signed-off-by: Rajendra Nayak<rnayak@ti.com> >
On Wed, Jul 4, 2012 at 5:57 PM, Prashant Gaikwad <pgaikwad@nvidia.com> wrote: > On Tuesday 03 July 2012 04:42 PM, Rajendra Nayak wrote: >> >> The below commit introduced a bug in __clk_set_parent() >> which could cause it to *skip* the parent validation >> which makes sure the parent passed to the api is a valid >> one. > > > Need this fix for Tegra too. > Hi Prashant, You'll find it if you pull the latest clk-next. Regards, Mike > >> commit 7975059db572eb47f0fb272a62afeae272a4b209 >> Author: Rajendra Nayak<rnayak@ti.com> >> Date: Wed Jun 6 14:41:31 2012 +0530 >> >> clk: Allow late cache allocation for clk->parents >> >> This was identified by the following compiler warning.. >> >> drivers/clk/clk.c: In function '__clk_set_parent': >> drivers/clk/clk.c:1083:5: warning: 'i' may be used uninitialized in >> this function [-Wuninitialized] >> >> .. as reported by Marc Kleine-Budde. >> >> There were various options discussed on how to fix this, one >> being initing 'i' to clk->num_parents, but the below approach >> was found to be more appropriate as it also makes the 'parent >> validation' code simpler to read. >> >> Reported-by: Marc Kleine-Budde<mkl@pengutronix.de> >> Signed-off-by: Rajendra Nayak<rnayak@ti.com> >> >
diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c index 8996f46..46317cb 100644 --- a/drivers/clk/clk.c +++ b/drivers/clk/clk.c @@ -1067,26 +1067,24 @@ static int __clk_set_parent(struct clk *clk, struct clk *parent) old_parent = clk->parent; - /* find index of new parent clock using cached parent ptrs */ - if (clk->parents) - for (i = 0; i < clk->num_parents; i++) - if (clk->parents[i] == parent) - break; - else + if (!clk->parents) clk->parents = kzalloc((sizeof(struct clk*) * clk->num_parents), GFP_KERNEL); /* - * find index of new parent clock using string name comparison - * also try to cache the parent to avoid future calls to __clk_lookup + * find index of new parent clock using cached parent ptrs, + * or if not yet cached, use string name comparison and cache + * them now to avoid future calls to __clk_lookup. */ - if (i == clk->num_parents) - for (i = 0; i < clk->num_parents; i++) - if (!strcmp(clk->parent_names[i], parent->name)) { - if (clk->parents) - clk->parents[i] = __clk_lookup(parent->name); - break; - } + for (i = 0; i < clk->num_parents; i++) { + if (clk->parents && clk->parents[i] == parent) + break; + else if (!strcmp(clk->parent_names[i], parent->name)) { + if (clk->parents) + clk->parents[i] = __clk_lookup(parent->name); + break; + } + } if (i == clk->num_parents) { pr_debug("%s: clock %s is not a possible parent of clock %s\n",
The below commit introduced a bug in __clk_set_parent() which could cause it to *skip* the parent validation which makes sure the parent passed to the api is a valid one. commit 7975059db572eb47f0fb272a62afeae272a4b209 Author: Rajendra Nayak <rnayak@ti.com> Date: Wed Jun 6 14:41:31 2012 +0530 clk: Allow late cache allocation for clk->parents This was identified by the following compiler warning.. drivers/clk/clk.c: In function '__clk_set_parent': drivers/clk/clk.c:1083:5: warning: 'i' may be used uninitialized in this function [-Wuninitialized] .. as reported by Marc Kleine-Budde. There were various options discussed on how to fix this, one being initing 'i' to clk->num_parents, but the below approach was found to be more appropriate as it also makes the 'parent validation' code simpler to read. Reported-by: Marc Kleine-Budde <mkl@pengutronix.de> Signed-off-by: Rajendra Nayak <rnayak@ti.com> --- drivers/clk/clk.c | 28 +++++++++++++--------------- 1 files changed, 13 insertions(+), 15 deletions(-)