| Message ID | 1389096223-23934-1-git-send-email-s.nawrocki@samsung.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Hi, Sylwester Nawrocki wrote: > Ensure clk->kref is dereferenced only when clk is not NULL. > > Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com> > --- > Hi Sachin, > > please try if this patch fixes the exyno5420 boot crash. > > Thanks, > Sylwester > > 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 e3e0327..a1fe86f 100644 > --- a/drivers/clk/clk.c > +++ b/drivers/clk/clk.c > @@ -2179,24 +2179,25 @@ EXPORT_SYMBOL_GPL(devm_clk_unregister); > */ > int __clk_get(struct clk *clk) > { > - if (clk && !try_module_get(clk->owner)) > - return 0; > + if (clk) { > + if (!try_module_get(clk->owner)) > + return 0; > This change is unnecessary! The part after the && is only evaluated when clk is not NULL. Lothar Waßmann
Hi, On 07/01/14 14:00, Lothar Waßmann wrote: > Sylwester Nawrocki wrote: >> Ensure clk->kref is dereferenced only when clk is not NULL. >> >> Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com> >> --- >> Hi Sachin, >> >> please try if this patch fixes the exyno5420 boot crash. >> >> Thanks, >> Sylwester >> >> 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 e3e0327..a1fe86f 100644 >> --- a/drivers/clk/clk.c >> +++ b/drivers/clk/clk.c >> @@ -2179,24 +2179,25 @@ EXPORT_SYMBOL_GPL(devm_clk_unregister); >> */ >> int __clk_get(struct clk *clk) >> { >> - if (clk && !try_module_get(clk->owner)) >> - return 0; >> + if (clk) { >> + if (!try_module_get(clk->owner)) >> + return 0; >> > This change is unnecessary! The part after the && is only evaluated > when clk is not NULL. It is, but to ensure there is no NULL clk passed at the kref_get(&clk->ref) line everything got moved under a common "if (clk) { }". The code will look like this: ----------- if (clk) { if (!try_module_get(clk->owner)) return 0; kref_get(&clk->ref); } ------------ If preferred I could make it: ------------ if (clk && !try_module_get(clk->owner)) return 0; if (clk) kref_get(&clk->ref); ------------ -- Regards, Sylwester
Hi Sylwester, On 7 January 2014 17:33, Sylwester Nawrocki <s.nawrocki@samsung.com> wrote: > Ensure clk->kref is dereferenced only when clk is not NULL. > > Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com> > --- > Hi Sachin, > > please try if this patch fixes the exyno5420 boot crash. Confirmed that this patch works fine on 5420 as well as already working 4210 and 5250 boards. Thanks for the quick fix. Tested-by: Sachin Kamat <sachin.kamat@linaro.org>
On 08/01/14 05:44, Sachin Kamat wrote: > Hi Sylwester, > > On 7 January 2014 17:33, Sylwester Nawrocki <s.nawrocki@samsung.com> wrote: >> Ensure clk->kref is dereferenced only when clk is not NULL. >> >> Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com> >> --- >> Hi Sachin, >> >> please try if this patch fixes the exyno5420 boot crash. > > Confirmed that this patch works fine on 5420 as well as already > working 4210 and 5250 boards. > Thanks for the quick fix. > > Tested-by: Sachin Kamat <sachin.kamat@linaro.org> Thanks Sachin. Mike, it seems we need this patch on top of my clk-unregister branch. Sorry for overlooking this issue. Could you add the $subject patch to your clk-next tree ? Regards, Sylwester
On 10 January 2014 15:34, Sylwester Nawrocki <s.nawrocki@samsung.com> wrote: > On 08/01/14 05:44, Sachin Kamat wrote: >> Hi Sylwester, >> >> On 7 January 2014 17:33, Sylwester Nawrocki <s.nawrocki@samsung.com> wrote: >>> Ensure clk->kref is dereferenced only when clk is not NULL. >>> >>> Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com> >>> --- >>> Hi Sachin, >>> >>> please try if this patch fixes the exyno5420 boot crash. >> >> Confirmed that this patch works fine on 5420 as well as already >> working 4210 and 5250 boards. >> Thanks for the quick fix. >> >> Tested-by: Sachin Kamat <sachin.kamat@linaro.org> > > Thanks Sachin. Mike, it seems we need this patch on top of > my clk-unregister branch. Sorry for overlooking this issue. > Could you add the $subject patch to your clk-next tree ? Gentle ping Mike. Hope we can have this patch in rc-2.
On 30/01/14 05:50, Sachin Kamat wrote: > On 10 January 2014 15:34, Sylwester Nawrocki <s.nawrocki@samsung.com> wrote: >> > On 08/01/14 05:44, Sachin Kamat wrote: >>> >> Hi Sylwester, >>> >> >>> >> On 7 January 2014 17:33, Sylwester Nawrocki <s.nawrocki@samsung.com> wrote: >>>> >>> Ensure clk->kref is dereferenced only when clk is not NULL. >>>> >>> >>>> >>> Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com> >>>> >>> --- >>>> >>> Hi Sachin, >>>> >>> >>>> >>> please try if this patch fixes the exyno5420 boot crash. >>> >> >>> >> Confirmed that this patch works fine on 5420 as well as already >>> >> working 4210 and 5250 boards. >>> >> Thanks for the quick fix. >>> >> >>> >> Tested-by: Sachin Kamat <sachin.kamat@linaro.org> >> > >> > Thanks Sachin. Mike, it seems we need this patch on top of >> > my clk-unregister branch. Sorry for overlooking this issue. >> > Could you add the $subject patch to your clk-next tree ? > > Gentle ping Mike. Hope we can have this patch in rc-2. A gentle reminder, this patch is still not in current -rc and is required to fix booting of some exynos platforms. Thanks, Sylwester
Mike, On 10.02.2014 16:02, Sylwester Nawrocki wrote: > On 30/01/14 05:50, Sachin Kamat wrote: >> On 10 January 2014 15:34, Sylwester Nawrocki <s.nawrocki@samsung.com> wrote: >>>> On 08/01/14 05:44, Sachin Kamat wrote: >>>>>> Hi Sylwester, >>>>>> >>>>>> On 7 January 2014 17:33, Sylwester Nawrocki <s.nawrocki@samsung.com> wrote: >>>>>>>> Ensure clk->kref is dereferenced only when clk is not NULL. >>>>>>>> >>>>>>>> Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com> >>>>>>>> --- >>>>>>>> Hi Sachin, >>>>>>>> >>>>>>>> please try if this patch fixes the exyno5420 boot crash. >>>>>> >>>>>> Confirmed that this patch works fine on 5420 as well as already >>>>>> working 4210 and 5250 boards. >>>>>> Thanks for the quick fix. >>>>>> >>>>>> Tested-by: Sachin Kamat <sachin.kamat@linaro.org> >>>> >>>> Thanks Sachin. Mike, it seems we need this patch on top of >>>> my clk-unregister branch. Sorry for overlooking this issue. >>>> Could you add the $subject patch to your clk-next tree ? >> >> Gentle ping Mike. Hope we can have this patch in rc-2. > > A gentle reminder, this patch is still not in current -rc and is required > to fix booting of some exynos platforms. It's been one and a half of a month since Sylwester posted this patch. Sorry for nagging, but for this whole period we've been observing complete breakage of several platforms, including Exynos4412-Trats2 board, due to NULL pointer dereference at boot-up time, so I'd consider this patch a _critical_ fix. Can we expect this patch to be applied to your tree and sent for next rc release or I should apply it to my tree and send a pull request to Linus directly? Best regards, Tomasz
Quoting Sylwester Nawrocki (2014-01-07 04:03:43) > Ensure clk->kref is dereferenced only when clk is not NULL. > > Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com> Taken into clk-fixes toward -rc5. Thanks! Mike > --- > Hi Sachin, > > please try if this patch fixes the exyno5420 boot crash. > > Thanks, > Sylwester > > 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 e3e0327..a1fe86f 100644 > --- a/drivers/clk/clk.c > +++ b/drivers/clk/clk.c > @@ -2179,24 +2179,25 @@ EXPORT_SYMBOL_GPL(devm_clk_unregister); > */ > int __clk_get(struct clk *clk) > { > - if (clk && !try_module_get(clk->owner)) > - return 0; > + if (clk) { > + if (!try_module_get(clk->owner)) > + return 0; > > - kref_get(&clk->ref); > + kref_get(&clk->ref); > + } > return 1; > } > > void __clk_put(struct clk *clk) > { > - if (WARN_ON_ONCE(IS_ERR(clk))) > + if (!clk || WARN_ON_ONCE(IS_ERR(clk))) > return; > > clk_prepare_lock(); > kref_put(&clk->ref, __clk_release); > clk_prepare_unlock(); > > - if (clk) > - module_put(clk->owner); > + module_put(clk->owner); > } > > /*** clk rate change notifiers ***/ > -- > 1.7.9.5 >
Hi Mike, On 25.02.2014 07:16, Mike Turquette wrote: > Quoting Sylwester Nawrocki (2014-01-07 04:03:43) >> Ensure clk->kref is dereferenced only when clk is not NULL. >> >> Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com> > > Taken into clk-fixes toward -rc5. Thanks! \o/ Best regards, Tomasz > > Thanks! > Mike > >> --- >> Hi Sachin, >> >> please try if this patch fixes the exyno5420 boot crash. >> >> Thanks, >> Sylwester >> >> 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 e3e0327..a1fe86f 100644 >> --- a/drivers/clk/clk.c >> +++ b/drivers/clk/clk.c >> @@ -2179,24 +2179,25 @@ EXPORT_SYMBOL_GPL(devm_clk_unregister); >> */ >> int __clk_get(struct clk *clk) >> { >> - if (clk && !try_module_get(clk->owner)) >> - return 0; >> + if (clk) { >> + if (!try_module_get(clk->owner)) >> + return 0; >> >> - kref_get(&clk->ref); >> + kref_get(&clk->ref); >> + } >> return 1; >> } >> >> void __clk_put(struct clk *clk) >> { >> - if (WARN_ON_ONCE(IS_ERR(clk))) >> + if (!clk || WARN_ON_ONCE(IS_ERR(clk))) >> return; >> >> clk_prepare_lock(); >> kref_put(&clk->ref, __clk_release); >> clk_prepare_unlock(); >> >> - if (clk) >> - module_put(clk->owner); >> + module_put(clk->owner); >> } >> >> /*** clk rate change notifiers ***/ >> -- >> 1.7.9.5 >>
diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c index e3e0327..a1fe86f 100644 --- a/drivers/clk/clk.c +++ b/drivers/clk/clk.c @@ -2179,24 +2179,25 @@ EXPORT_SYMBOL_GPL(devm_clk_unregister); */ int __clk_get(struct clk *clk) { - if (clk && !try_module_get(clk->owner)) - return 0; + if (clk) { + if (!try_module_get(clk->owner)) + return 0; - kref_get(&clk->ref); + kref_get(&clk->ref); + } return 1; } void __clk_put(struct clk *clk) { - if (WARN_ON_ONCE(IS_ERR(clk))) + if (!clk || WARN_ON_ONCE(IS_ERR(clk))) return; clk_prepare_lock(); kref_put(&clk->ref, __clk_release); clk_prepare_unlock(); - if (clk) - module_put(clk->owner); + module_put(clk->owner); } /*** clk rate change notifiers ***/
Ensure clk->kref is dereferenced only when clk is not NULL. Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com> --- Hi Sachin, please try if this patch fixes the exyno5420 boot crash. Thanks, Sylwester drivers/clk/clk.c | 13 +++++++------ 1 file changed, 7 insertions(+), 6 deletions(-) -- 1.7.9.5