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Quanyang Wang 1f683fd2c2 drm/xlnx: fix kmemleak by sending vblank_event in atomic_disable
[ Upstream commit a7e02f7796 ]

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>
2021-02-26 10:13:01 +01:00
arch KVM: x86: Zap the oldest MMU pages, not the newest 2021-02-26 10:13:00 +01:00
block bfq-iosched: Revert "bfq: Fix computation of shallow depth" 2021-02-17 11:02:24 +01:00
certs .gitignore: add SPDX License Identifier 2020-03-25 11:50:48 +01:00
crypto crypto: xor - Fix divide error in do_xor_speed() 2021-01-27 11:54:52 +01:00
Documentation ovl: implement volatile-specific fsync error behaviour 2021-02-10 09:29:16 +01:00
drivers drm/xlnx: fix kmemleak by sending vblank_event in atomic_disable 2021-02-26 10:13:01 +01:00
fs mm: provide a saner PTE walking API for modules 2021-02-26 10:13:01 +01:00
include mm: provide a saner PTE walking API for modules 2021-02-26 10:13:01 +01:00
init fgraph: Initialize tracing_graph_pause at task creation 2021-02-10 09:29:16 +01:00
ipc ipc: adjust proc_ipc_sem_dointvec definition to match prototype 2020-09-05 12:14:29 -07:00
kernel bpf: Fix truncation handling for mod32 dst reg wrt zero 2021-02-26 10:12:59 +01:00
lib udp: fix skb_copy_and_csum_datagram with odd segment sizes 2021-02-17 11:02:28 +01:00
LICENSES LICENSES/deprecated: add Zlib license text 2020-09-16 14:33:49 +02:00
mm mm: provide a saner PTE walking API for modules 2021-02-26 10:13:01 +01:00
net RDMA: Lift ibdev_to_node from rds to common code 2021-02-26 10:12:59 +01:00
samples samples/bpf: Fix possible hang in xdpsock with multiple threads 2020-12-30 11:53:49 +01:00
scripts scripts: set proper OpenSSL include dir also for sign-file 2021-02-17 11:02:28 +01:00
security cap: fix conversions on getxattr 2021-02-17 11:02:22 +01:00
sound ASoC: Intel: sof_sdw: set proper flags for Dell TGL-H SKU 0A5E 2021-02-13 13:55:07 +01:00
tools selftests: txtimestamp: fix compilation issue 2021-02-17 11:02:26 +01:00
usr Merge branch 'work.fdpic' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2020-08-07 13:29:39 -07:00
virt KVM: Use kvm_pfn_t for local PFN variable in hva_to_pfn_remapped() 2021-02-26 10:13:01 +01:00
.clang-format RDMA 5.10 pull request 2020-10-17 11:18:18 -07:00
.cocciconfig
.get_maintainer.ignore
.gitattributes .gitattributes: use 'dts' diff driver for dts files 2019-12-04 19:44:11 -08:00
.gitignore .gitignore: docs: ignore sphinx_*/ directories 2020-09-10 10:44:31 -06:00
.mailmap mailmap: add two more addresses of Uwe Kleine-König 2020-12-06 10:19:07 -08:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS MAINTAINERS: Move Jason Cooper to CREDITS 2020-11-30 10:20:34 +01:00
Kbuild kbuild: rename hostprogs-y/always to hostprogs/always-y 2020-02-04 01:53:07 +09:00
Kconfig kbuild: ensure full rebuild when the compiler is updated 2020-05-12 13:28:33 +09:00
MAINTAINERS Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2020-12-10 15:30:13 -08:00
Makefile Linux 5.10.18 2021-02-23 15:53:25 +01:00
README

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