On Sat, Mar 31, 2018 at 10:09:40PM +0200, Stefan Wahren wrote: > The kernel would like to have all stack VLA usage removed[1]. The array > here is fixed (declared with a const variable) but it appears like a VLA > to the compiler. Also, currently we are putting 768 bytes on the > stack. So save stack space and removes the VLA build warning by > making it static. > > [1]: https://lkml.org/lkml/2018/3/7/621 > > CC: Tobin C. Harding <me@xxxxxxxx> > Signed-off-by: Stefan Wahren <stefan.wahren@xxxxxxxx> > --- > .../vc04_services/interface/vchiq_arm/vchiq_arm.c | 20 ++++++++++---------- > 1 file changed, 10 insertions(+), 10 deletions(-) > > diff --git a/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.c b/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.c > index 24d456b..f276437 100644 > --- a/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.c > +++ b/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.c > @@ -3414,13 +3414,18 @@ vchiq_release_service(VCHIQ_SERVICE_HANDLE_T handle) > return ret; > } > > +struct service_data_struct { > + int fourcc; > + int clientid; > + int use_count; > +}; > + > void > vchiq_dump_service_use_state(VCHIQ_STATE_T *state) > { > VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state); > + static struct service_data_struct service_data[64]; > int i, j = 0; > - /* Only dump 64 services */ > - static const int local_max_services = 64; > /* If there's more than 64 services, only dump ones with > * non-zero counts */ > int only_nonzero = 0; > @@ -3431,11 +3436,6 @@ vchiq_dump_service_use_state(VCHIQ_STATE_T *state) > int peer_count; > int vc_use_count; > int active_services; > - struct service_data_struct { > - int fourcc; > - int clientid; > - int use_count; > - } service_data[local_max_services]; > > if (!arm_state) > return; > @@ -3446,10 +3446,10 @@ vchiq_dump_service_use_state(VCHIQ_STATE_T *state) > peer_count = arm_state->peer_use_count; > vc_use_count = arm_state->videocore_use_count; > active_services = state->unused_service; > - if (active_services > local_max_services) > + if (active_services > ARRAY_SIZE(service_data)) > only_nonzero = 1; > > - for (i = 0; (i < active_services) && (j < local_max_services); i++) { > + for (i = 0; (i < active_services) && (j < ARRAY_SIZE(service_data)); i++) { > VCHIQ_SERVICE_T *service_ptr = state->services[i]; > > if (!service_ptr) > @@ -3479,7 +3479,7 @@ vchiq_dump_service_use_state(VCHIQ_STATE_T *state) > vchiq_log_warning(vchiq_susp_log_level, "Too many active " > "services (%d). Only dumping up to first %d services " > "with non-zero use-count", active_services, > - local_max_services); > + ARRAY_SIZE(service_data)); > > for (i = 0; i < j; i++) { > vchiq_log_warning(vchiq_susp_log_level, > -- > 2.7.4 > On a previous attempt to fix this VLA Linus commented that 64 was too big (it equates to 768 bytes on the stack). Here is that email for your reference https://lkml.org/lkml/2018/3/9/744 I didn't understand what he meant by 'just do the stack size limitation' Hope this helps, Tobin. _______________________________________________ devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxx http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel
