From f5069622bb6233e62f8842c5136f2ea5e8c1e0c8 Mon Sep 17 00:00:00 2001 From: Konsta Holtta Date: Thu, 6 Oct 2016 13:13:36 +0300 Subject: gpu: nvgpu: make sure vidmem is cleared only once Protect the initial vidmem zeroing performed during the first userspace alloc with a mutex, so that it blocks next concurrent users and is run only once. Otherwise, multiple clears could end up running in parallel, so that the next ones corrupt memory allocated by the thread that has finished earlier and advanced to allocate and use memory. Jira DNVGPU-84 Change-Id: If497749abf481b230835250191d011c4a9d1483b Signed-off-by: Konsta Holtta Reviewed-on: http://git-master/r/1232461 (cherry picked from commit 79435a68e6d2713b78acdb0ec6f77cfd78651d7f) Reviewed-on: http://git-master/r/1234990 GVS: Gerrit_Virtual_Submit Reviewed-by: Terje Bergstrom --- drivers/gpu/nvgpu/gk20a/mm_gk20a.c | 15 +++++++++++---- 1 file changed, 11 insertions(+), 4 deletions(-) (limited to 'drivers/gpu/nvgpu/gk20a/mm_gk20a.c') diff --git a/drivers/gpu/nvgpu/gk20a/mm_gk20a.c b/drivers/gpu/nvgpu/gk20a/mm_gk20a.c index 570a3708..4c55f8ce 100644 --- a/drivers/gpu/nvgpu/gk20a/mm_gk20a.c +++ b/drivers/gpu/nvgpu/gk20a/mm_gk20a.c @@ -947,6 +947,8 @@ static int gk20a_init_vidmem(struct mm_gk20a *mm) mm->vidmem.bootstrap_base = bootstrap_base; mm->vidmem.bootstrap_size = bootstrap_size; + mutex_init(&mm->vidmem.first_clear_mutex); + INIT_WORK(&mm->vidmem.clear_mem_worker, gk20a_vidmem_clear_mem_worker); atomic_set(&mm->vidmem.clears_pending, 0); INIT_LIST_HEAD(&mm->vidmem.clear_list_head); @@ -2190,11 +2192,16 @@ int gk20a_vidmem_buf_alloc(struct gk20a *g, size_t bytes) buf->g = g; if (!g->mm.vidmem.cleared) { - err = gk20a_vidmem_clear_all(g); - if (err) { - gk20a_err(g->dev, "failed to clear whole vidmem"); - goto err_kfree; + mutex_lock(&g->mm.vidmem.first_clear_mutex); + if (!g->mm.vidmem.cleared) { + err = gk20a_vidmem_clear_all(g); + if (err) { + gk20a_err(g->dev, + "failed to clear whole vidmem"); + goto err_kfree; + } } + mutex_unlock(&g->mm.vidmem.first_clear_mutex); } buf->mem = kzalloc(sizeof(struct mem_desc), GFP_KERNEL); -- cgit v1.2.2