[ Upstream commit a7e02f7796c163ac8297b30223bf24bade9f8a50 ]
When running xrandr to change resolution of DP, the kmemleak as below
can be observed:
unreferenced object 0xffff00080a351000 (size 256):
comm "Xorg", pid 248, jiffies 4294899614 (age 19.960s)
hex dump (first 32 bytes):
98 a0 bc 01 08 00 ff ff 01 00 00 00 00 00 00 00 ................
ff ff ff ff 00 00 00 00 00 00 00 00 00 00 00 00 ................
backtrace:
[<00000000e0bd0f69>] kmemleak_alloc+0x30/0x40
[<00000000cde2f318>] kmem_cache_alloc+0x3d4/0x588
[<0000000088ea9bd7>] drm_atomic_helper_setup_commit+0x84/0x5f8
[<000000002290a264>] drm_atomic_helper_commit+0x58/0x388
[<00000000f6ea78c3>] drm_atomic_commit+0x4c/0x60
[<00000000c8e0725e>] drm_atomic_connector_commit_dpms+0xe8/0x110
[<0000000020ade187>] drm_mode_obj_set_property_ioctl+0x1b0/0x450
[<00000000918206d6>] drm_connector_property_set_ioctl+0x3c/0x68
[<000000008d51e7a5>] drm_ioctl_kernel+0xc4/0x118
[<000000002a819b75>] drm_ioctl+0x214/0x448
[<000000008ca4e588>] __arm64_sys_ioctl+0xa8/0xf0
[<0000000034e15a35>] el0_svc_common.constprop.0+0x74/0x190
[<000000001b93d916>] do_el0_svc+0x24/0x90
[<00000000ce9230e0>] el0_svc+0x14/0x20
[<00000000e3607d82>] el0_sync_handler+0xb0/0xb8
[<000000003e79c15f>] el0_sync+0x174/0x180
This is because there is a scenario that a drm_crtc_commit commit is
allocated but not freed. The drm subsystem require/release references
to a CRTC commit by calling drm_crtc_commit_get/put, and when
drm_crtc_commit_put find that commit.ref.refcount is zero, it will
call __drm_crtc_commit_free to free this CRTC commit. Among these
drm_crtc_commit_get/put pairs, there is a drm_crtc_commit_get in
drm_atomic_helper_setup_commit as below:
...
new_crtc_state->event->base.completion = &commit->flip_done;
new_crtc_state->event->base.completion_release = release_crtc_commit;
drm_crtc_commit_get(commit);
...
This reference to the CRTC commit should be released at the function
release_crtc_commit by calling e->completion_release(e->completion) in
drm_send_event_locked. So we need to call drm_send_event_locked at
two places: handling vblank event in the irq handler and the crtc disable
helper. But in zynqmp_disp_crtc_atomic_disable, it only marks the flip
is done and not call drm_crtc_commit_put. This result that the refcount
of this commit is always non-zero and this commit will never be freed.
Since the function drm_crtc_send_vblank_event has operations both sending
a flip_done signal and releasing reference to the CRTC commit, let's use
it instead.
Signed-off-by: Quanyang Wang <quanyang.wang@windriver.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20210202064121.173362-1-quanyang.wang@windriver.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
The Xilinx ZynqMP SoC has a hardened display pipeline named DisplayPort
Subsystem. It includes a buffer manager, a video pipeline renderer
(blender), an audio mixer and a DisplayPort source controller
(transmitter). The DMA engine the provide data to the buffer manager, as
well as the DisplayPort PHYs that drive the lanes, are external to the
subsystem and interfaced using the DMA engine and PHY APIs respectively.
This driver supports the DisplayPort Subsystem and implements
- Two planes, for graphics and video
- One CRTC that supports alpha blending
- One encoder for the DisplayPort transmitter
- One connector for an external monitor
It currently doesn't support
- Color keying
- Test pattern generation
- Audio
- Live input from the Programmable Logic (FPGA)
- Output to the Programmable Logic (FPGA)
Signed-off-by: Hyun Kwon <hyun.kwon@xilinx.com>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
