Message ID | 1399481332-9550-1-git-send-email-maxime.coquelin@st.com |
---|---|
State | Accepted |
Commit | fe52e7505f8bf365d5ab0eeee19ababe406cbaaf |
Headers | show |
Hi Mike, On Wed, May 7, 2014 at 1:48 PM, Maxime COQUELIN <maxime.coquelin@st.com> wrote: > Commit 1d9fe6b97 ("clk: divider: Fix best div calculation for power-of-two and > table dividers") introduces a regression in its _table_round_up function. > > When the divider passed to this function is greater than the max divider > available in the table, this function returns table's max divider. > Problem is that it causes an infinite loop in clk_divider_bestdiv() because > _next_div() will never return a value greater than maxdiv. > > Instead of returning table's max divider, this patch returns INT_MAX. > > Reported-by: Fabio Estevam <festevam@gmail.com> > Reported-by: Shawn Guo <shawn.guo@freescale.com> > Tested-by: Fabio Estevam <festevam@gmail.com> > Cc: Mike Turquette <mike.turquette@linaro.org> > Signed-off-by: Maxime Coquelin <maxime.coquelin@st.com> Any comments on this one? It does fix a regression. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Hi Mike, On 05/15/2014 03:28 PM, Fabio Estevam wrote: > Hi Mike, > > On Wed, May 7, 2014 at 1:48 PM, Maxime COQUELIN <maxime.coquelin@st.com> wrote: >> Commit 1d9fe6b97 ("clk: divider: Fix best div calculation for power-of-two and >> table dividers") introduces a regression in its _table_round_up function. >> >> When the divider passed to this function is greater than the max divider >> available in the table, this function returns table's max divider. >> Problem is that it causes an infinite loop in clk_divider_bestdiv() because >> _next_div() will never return a value greater than maxdiv. >> >> Instead of returning table's max divider, this patch returns INT_MAX. >> >> Reported-by: Fabio Estevam <festevam@gmail.com> >> Reported-by: Shawn Guo <shawn.guo@freescale.com> >> Tested-by: Fabio Estevam <festevam@gmail.com> >> Cc: Mike Turquette <mike.turquette@linaro.org> >> Signed-off-by: Maxime Coquelin <maxime.coquelin@st.com> > > Any comments on this one? It does fix a regression. > This patch is important as it fixes a regression, could you review it please? Thanks, Maxime -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Quoting Maxime COQUELIN (2014-05-07 09:48:52) > Commit 1d9fe6b97 ("clk: divider: Fix best div calculation for power-of-two and > table dividers") introduces a regression in its _table_round_up function. > > When the divider passed to this function is greater than the max divider > available in the table, this function returns table's max divider. > Problem is that it causes an infinite loop in clk_divider_bestdiv() because > _next_div() will never return a value greater than maxdiv. > > Instead of returning table's max divider, this patch returns INT_MAX. > > Reported-by: Fabio Estevam <festevam@gmail.com> > Reported-by: Shawn Guo <shawn.guo@freescale.com> > Tested-by: Fabio Estevam <festevam@gmail.com> > Cc: Mike Turquette <mike.turquette@linaro.org> > Signed-off-by: Maxime Coquelin <maxime.coquelin@st.com> Pulled into clk-fixes for -rc7. Regards, Mike > --- > drivers/clk/clk-divider.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/clk/clk-divider.c b/drivers/clk/clk-divider.c > index b3c8396..cf9114a 100644 > --- a/drivers/clk/clk-divider.c > +++ b/drivers/clk/clk-divider.c > @@ -158,7 +158,7 @@ static bool _is_valid_div(struct clk_divider *divider, unsigned int div) > static int _round_up_table(const struct clk_div_table *table, int div) > { > const struct clk_div_table *clkt; > - int up = _get_table_maxdiv(table); > + int up = INT_MAX; > > for (clkt = table; clkt->div; clkt++) { > if (clkt->div == div) > -- > 1.9.1 > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
On 05/23/2014 11:39 PM, Mike Turquette wrote: > Quoting Maxime COQUELIN (2014-05-07 09:48:52) >> Commit 1d9fe6b97 ("clk: divider: Fix best div calculation for power-of-two and >> table dividers") introduces a regression in its _table_round_up function. >> >> When the divider passed to this function is greater than the max divider >> available in the table, this function returns table's max divider. >> Problem is that it causes an infinite loop in clk_divider_bestdiv() because >> _next_div() will never return a value greater than maxdiv. >> >> Instead of returning table's max divider, this patch returns INT_MAX. >> >> Reported-by: Fabio Estevam <festevam@gmail.com> >> Reported-by: Shawn Guo <shawn.guo@freescale.com> >> Tested-by: Fabio Estevam <festevam@gmail.com> >> Cc: Mike Turquette <mike.turquette@linaro.org> >> Signed-off-by: Maxime Coquelin <maxime.coquelin@st.com> > > Pulled into clk-fixes for -rc7. Thanks Mike. Regards, Maxime > > Regards, > Mike > >> --- >> drivers/clk/clk-divider.c | 2 +- >> 1 file changed, 1 insertion(+), 1 deletion(-) >> >> diff --git a/drivers/clk/clk-divider.c b/drivers/clk/clk-divider.c >> index b3c8396..cf9114a 100644 >> --- a/drivers/clk/clk-divider.c >> +++ b/drivers/clk/clk-divider.c >> @@ -158,7 +158,7 @@ static bool _is_valid_div(struct clk_divider *divider, unsigned int div) >> static int _round_up_table(const struct clk_div_table *table, int div) >> { >> const struct clk_div_table *clkt; >> - int up = _get_table_maxdiv(table); >> + int up = INT_MAX; >> >> for (clkt = table; clkt->div; clkt++) { >> if (clkt->div == div) >> -- >> 1.9.1 >> -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
diff --git a/drivers/clk/clk-divider.c b/drivers/clk/clk-divider.c index b3c8396..cf9114a 100644 --- a/drivers/clk/clk-divider.c +++ b/drivers/clk/clk-divider.c @@ -158,7 +158,7 @@ static bool _is_valid_div(struct clk_divider *divider, unsigned int div) static int _round_up_table(const struct clk_div_table *table, int div) { const struct clk_div_table *clkt; - int up = _get_table_maxdiv(table); + int up = INT_MAX; for (clkt = table; clkt->div; clkt++) { if (clkt->div == div)