drm_mm_insert_node_generic and drm_mm_remove_node may access same resource with list ops, it's not threads safe, so protect this context with mutex lock.
Fix bug: [49451.856244] ================================================================== [49451.856350] BUG: KASAN: wild-memory-access on address dead000000000108 [49451.856379] Write of size 8 by task Binder:218_4/683 [49451.856417] CPU: 2 PID: 683 Comm: Binder:218_4 Not tainted 4.4.36 #62 [49451.856443] Hardware name: Rockchip RK3399 Excavator Board edp (Android) (DT) [49451.856469] Call trace: [49451.856519] [<ffffff900808a9d0>] dump_backtrace+0x0/0x230 [49451.856556] [<ffffff900808ac14>] show_stack+0x14/0x1c [49451.856592] [<ffffff90084a4de0>] dump_stack+0xa0/0xc8 [49451.856633] [<ffffff900821b700>] kasan_report+0x110/0x4dc [49451.856670] [<ffffff900821aa84>] __asan_store8+0x24/0x7c [49451.856715] [<ffffff90086158c4>] drm_mm_insert_node_generic+0x2dc/0x464 [49451.856760] [<ffffff90086406a8>] rockchip_gem_iommu_map+0x60/0x158 [49451.856794] [<ffffff9008640bb4>] rockchip_gem_create_object+0x278/0x488 [49451.856827] [<ffffff9008641020>] rockchip_gem_create_with_handle+0x24/0x10c [49451.856862] [<ffffff9008641364>] rockchip_gem_create_ioctl+0x3c/0x50 [49451.856896] [<ffffff900860aee4>] drm_ioctl+0x354/0x52c [49451.856939] [<ffffff900823d948>] do_vfs_ioctl+0x670/0x78c [49451.856976] [<ffffff900823dac4>] SyS_ioctl+0x60/0x88 [49451.857009] [<ffffff9008082ef0>] el0_svc_naked+0x24/0x28
Change-Id: I2ea377aa9ca24f70c59e2d86f2a6ad5ccb9c0891 Signed-off-by: Mark Yao mark.yao@rock-chips.com --- drivers/gpu/drm/rockchip/rockchip_drm_drv.c | 1 + drivers/gpu/drm/rockchip/rockchip_drm_drv.h | 2 ++ drivers/gpu/drm/rockchip/rockchip_drm_gem.c | 9 +++++++++ 3 files changed, 12 insertions(+)
diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_drv.c b/drivers/gpu/drm/rockchip/rockchip_drm_drv.c index 7a610e9..b360e62 100644 --- a/drivers/gpu/drm/rockchip/rockchip_drm_drv.c +++ b/drivers/gpu/drm/rockchip/rockchip_drm_drv.c @@ -146,6 +146,7 @@ static int rockchip_drm_init_iommu(struct drm_device *drm_dev) DRM_DEBUG("IOMMU context initialized (aperture: %#llx-%#llx)\n", start, end); drm_mm_init(&private->mm, start, end - start + 1); + mutex_init(&private->mm_lock);
return 0; } diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_drv.h b/drivers/gpu/drm/rockchip/rockchip_drm_drv.h index 7c123d9..adc3930 100644 --- a/drivers/gpu/drm/rockchip/rockchip_drm_drv.h +++ b/drivers/gpu/drm/rockchip/rockchip_drm_drv.h @@ -62,6 +62,8 @@ struct rockchip_drm_private { const struct rockchip_crtc_funcs *crtc_funcs[ROCKCHIP_MAX_CRTC]; struct drm_atomic_state *state; struct iommu_domain *domain; + /* protect drm_mm on multi-threads */ + struct mutex mm_lock; struct drm_mm mm; struct list_head psr_list; spinlock_t psr_list_lock; diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_gem.c b/drivers/gpu/drm/rockchip/rockchip_drm_gem.c index 5209392..8d27965 100644 --- a/drivers/gpu/drm/rockchip/rockchip_drm_gem.c +++ b/drivers/gpu/drm/rockchip/rockchip_drm_gem.c @@ -28,9 +28,13 @@ static int rockchip_gem_iommu_map(struct rockchip_gem_object *rk_obj) int prot = IOMMU_READ | IOMMU_WRITE; ssize_t ret;
+ mutex_lock(&private->mm_lock); + ret = drm_mm_insert_node_generic(&private->mm, &rk_obj->mm, rk_obj->base.size, PAGE_SIZE, 0, 0); + + mutex_unlock(&private->mm_lock); if (ret < 0) { DRM_ERROR("out of I/O virtual memory: %zd\n", ret); return ret; @@ -61,8 +65,13 @@ static int rockchip_gem_iommu_unmap(struct rockchip_gem_object *rk_obj) struct rockchip_drm_private *private = drm->dev_private;
iommu_unmap(private->domain, rk_obj->dma_addr, rk_obj->size); + + mutex_lock(&private->mm_lock); + drm_mm_remove_node(&rk_obj->mm);
+ mutex_unlock(&private->mm_lock); + return 0; }