| Message ID | 20210618033132.24839-2-paul.davey@alliedtelesis.co.nz (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | bus: mhi: Fix MHI on big endian architectures | expand |
On Fri, Jun 18, 2021 at 03:31:31PM +1200, Paul Davey wrote: > On big endian architectures the mhi debugfs files which report pm state > give "Invalid State" for all states. > > Fix to_mhi_pm_state_str by using a local unsigned long as an intemediate > to pass the state to find_last_bit to avoid endianness issues with cast > from enum mhi_pm_state * to unsigned long *. > > Signed-off-by: Paul Davey <paul.davey@alliedtelesis.co.nz> Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org> Thanks, Mani > --- > drivers/bus/mhi/core/init.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/drivers/bus/mhi/core/init.c b/drivers/bus/mhi/core/init.c > index c81b377fca8f..87cc0c449078 100644 > --- a/drivers/bus/mhi/core/init.c > +++ b/drivers/bus/mhi/core/init.c > @@ -79,7 +79,8 @@ static const char * const mhi_pm_state_str[] = { > > const char *to_mhi_pm_state_str(enum mhi_pm_state state) > { > - int index = find_last_bit((unsigned long *)&state, 32); > + unsigned long tmp = state; > + int index = find_last_bit((unsigned long *)&tmp, 32); > > if (index >= ARRAY_SIZE(mhi_pm_state_str)) > return "Invalid State"; > -- > 2.32.0 >
Hi Paul, On Fri, 2021-06-18 at 15:31 +1200, Paul Davey wrote: > On big endian architectures the mhi debugfs files which report pm > state > give "Invalid State" for all states. > > Fix to_mhi_pm_state_str by using a local unsigned long as an > intemediate > to pass the state to find_last_bit to avoid endianness issues with > cast > from enum mhi_pm_state * to unsigned long *. > > Signed-off-by: Paul Davey <paul.davey@alliedtelesis.co.nz> > --- > drivers/bus/mhi/core/init.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/drivers/bus/mhi/core/init.c > b/drivers/bus/mhi/core/init.c > index c81b377fca8f..87cc0c449078 100644 > --- a/drivers/bus/mhi/core/init.c > +++ b/drivers/bus/mhi/core/init.c > @@ -79,7 +79,8 @@ static const char * const mhi_pm_state_str[] = { > > const char *to_mhi_pm_state_str(enum mhi_pm_state state) > { > - int index = find_last_bit((unsigned long *)&state, 32); > + unsigned long tmp = state; > + int index = find_last_bit((unsigned long *)&tmp, 32); > > if (index >= ARRAY_SIZE(mhi_pm_state_str)) > return "Invalid State"; Considering KASAN bugs reported in the past related to find_next_bit https://www.spinics.net/lists/alsa-devel/msg110946.html Since you are addressing the BE arch issue, would you please use this solution instead :- diff --git a/drivers/bus/mhi/core/init.c b/drivers/bus/mhi/core/init.c index 8f4cd4d..744b617 100644 --- a/drivers/bus/mhi/core/init.c +++ b/drivers/bus/mhi/core/init.c @@ -77,9 +77,12 @@ static const char * const mhi_pm_state_str[] = { const char *to_mhi_pm_state_str(enum mhi_pm_state state) { + int index; - if (index >= ARRAY_SIZE(mhi_pm_state_str)) + if (state) + index = __fls(state); + + if (!state || index >= ARRAY_SIZE(mhi_pm_state_str)) return "Invalid State"; return mhi_pm_state_str[index]; Thanks, Hemant
diff --git a/drivers/bus/mhi/core/init.c b/drivers/bus/mhi/core/init.c index c81b377fca8f..87cc0c449078 100644 --- a/drivers/bus/mhi/core/init.c +++ b/drivers/bus/mhi/core/init.c @@ -79,7 +79,8 @@ static const char * const mhi_pm_state_str[] = { const char *to_mhi_pm_state_str(enum mhi_pm_state state) { - int index = find_last_bit((unsigned long *)&state, 32); + unsigned long tmp = state; + int index = find_last_bit((unsigned long *)&tmp, 32); if (index >= ARRAY_SIZE(mhi_pm_state_str)) return "Invalid State";
On big endian architectures the mhi debugfs files which report pm state give "Invalid State" for all states. Fix to_mhi_pm_state_str by using a local unsigned long as an intemediate to pass the state to find_last_bit to avoid endianness issues with cast from enum mhi_pm_state * to unsigned long *. Signed-off-by: Paul Davey <paul.davey@alliedtelesis.co.nz> --- drivers/bus/mhi/core/init.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)