Re: [PATCH v2 3/7] drm/rockchip: gem: add mutex lock for drm mm

From: Mark yao
Date: Tue Feb 07 2017 - 19:36:20 EST


On 2017å02æ07æ 20:19, Thierry Reding wrote:
On Tue, Feb 07, 2017 at 04:35:38PM +0800, Mark Yao wrote:
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
This is meaningless in an upstream tree. Please remove.

Thierry
Right, Forget to remove "Change-Id: "

Thanks.

--
ïark Yao