1 files changed, 12 insertions, 2 deletions

diff --git a/drivers/gpu/nvgpu/common/semaphore.c b/drivers/gpu/nvgpu/common/semaphore.c
index e1e6c027..dfed3588 100644
--- a/drivers/gpu/nvgpu/common/semaphore.c
+++ b/drivers/gpu/nvgpu/common/semaphore.c
@@ -59,6 +59,7 @@ static int __nvgpu_semaphore_sea_grow(struct nvgpu_semaphore_sea *sea)
 {
         int ret = 0;
         struct gk20a *gk20a = sea->gk20a;
+        u32 i;
 
         __lock_sema_sea(sea);
 
@@ -71,6 +72,14 @@ static int __nvgpu_semaphore_sea_grow(struct nvgpu_semaphore_sea *sea)
         sea->size = SEMAPHORE_POOL_COUNT;
         sea->map_size = SEMAPHORE_POOL_COUNT * PAGE_SIZE;
 
+        /*
+         * Start the semaphores at values that will soon overflow the 32-bit
+         * integer range. This way any buggy comparisons would start to fail
+         * sooner rather than later.
+         */
+        for (i = 0; i < PAGE_SIZE * SEMAPHORE_POOL_COUNT; i += 4)
+                nvgpu_mem_wr(gk20a, &sea->sea_mem, i, 0xfffffff0);
+
 out:
         __unlock_sema_sea(sea);
         return ret;
@@ -345,6 +354,7 @@ static int __nvgpu_init_hw_sema(struct channel_gk20a *ch)
         int ret = 0;
         struct nvgpu_semaphore_int *hw_sema;
         struct nvgpu_semaphore_pool *p = ch->vm->sema_pool;
+        int current_value;
 
         BUG_ON(!p);
 
@@ -369,8 +379,8 @@ static int __nvgpu_init_hw_sema(struct channel_gk20a *ch)
         hw_sema->p = p;
         hw_sema->idx = hw_sema_idx;
         hw_sema->offset = SEMAPHORE_SIZE * hw_sema_idx;
-        nvgpu_atomic_set(&hw_sema->next_value, 0);
-        nvgpu_mem_wr(ch->g, &p->rw_mem, hw_sema->offset, 0);
+        current_value = nvgpu_mem_rd(ch->g, &p->rw_mem, hw_sema->offset);
+        nvgpu_atomic_set(&hw_sema->next_value, current_value);
 
         nvgpu_mutex_release(&p->pool_lock);