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baozhu.liu 0c8eda600e drm/komeda: drop all currently held locks if deadlock happens
[ Upstream commit 19ecbe8325a2a7ffda5ff4790955b84eaccba49f ]

If komeda_pipeline_unbound_components() returns -EDEADLK,
it means that a deadlock happened in the locking context.
Currently, komeda is not dealing with the deadlock properly,producing the
following output when CONFIG_DEBUG_WW_MUTEX_SLOWPATH is enabled:

 ------------[ cut here ]------------
[   26.103984] WARNING: CPU: 2 PID: 345 at drivers/gpu/drm/arm/display/komeda/komeda_pipeline_state.c:1248
	       komeda_release_unclaimed_resources+0x13c/0x170
[   26.117453] Modules linked in:
[   26.120511] CPU: 2 PID: 345 Comm: composer@2.1-se Kdump: loaded Tainted: G   W  5.10.110-SE-SDK1.8-dirty #16
[   26.131374] Hardware name: Siengine Se1000 Evaluation board (DT)
[   26.137379] pstate: 20400009 (nzCv daif +PAN -UAO -TCO BTYPE=--)
[   26.143385] pc : komeda_release_unclaimed_resources+0x13c/0x170
[   26.149301] lr : komeda_release_unclaimed_resources+0xbc/0x170
[   26.155130] sp : ffff800017b8b8d0
[   26.158442] pmr_save: 000000e0
[   26.161493] x29: ffff800017b8b8d0 x28: ffff000cf2f96200
[   26.166805] x27: ffff000c8f5a8800 x26: 0000000000000000
[   26.172116] x25: 0000000000000038 x24: ffff8000116a0140
[   26.177428] x23: 0000000000000038 x22: ffff000cf2f96200
[   26.182739] x21: ffff000cfc300300 x20: ffff000c8ab77080
[   26.188051] x19: 0000000000000003 x18: 0000000000000000
[   26.193362] x17: 0000000000000000 x16: 0000000000000000
[   26.198672] x15: b400e638f738ba38 x14: 0000000000000000
[   26.203983] x13: 0000000106400a00 x12: 0000000000000000
[   26.209294] x11: 0000000000000000 x10: 0000000000000000
[   26.214604] x9 : ffff800012f80000 x8 : ffff000ca3308000
[   26.219915] x7 : 0000000ff3000000 x6 : ffff80001084034c
[   26.225226] x5 : ffff800017b8bc40 x4 : 000000000000000f
[   26.230536] x3 : ffff000ca3308000 x2 : 0000000000000000
[   26.235847] x1 : 0000000000000000 x0 : ffffffffffffffdd
[   26.241158] Call trace:
[   26.243604] komeda_release_unclaimed_resources+0x13c/0x170
[   26.249175] komeda_crtc_atomic_check+0x68/0xf0
[   26.253706] drm_atomic_helper_check_planes+0x138/0x1f4
[   26.258929] komeda_kms_check+0x284/0x36c
[   26.262939] drm_atomic_check_only+0x40c/0x714
[   26.267381] drm_atomic_nonblocking_commit+0x1c/0x60
[   26.272344] drm_mode_atomic_ioctl+0xa3c/0xb8c
[   26.276787] drm_ioctl_kernel+0xc4/0x120
[   26.280708] drm_ioctl+0x268/0x534
[   26.284109] __arm64_sys_ioctl+0xa8/0xf0
[   26.288030] el0_svc_common.constprop.0+0x80/0x240
[   26.292817] do_el0_svc+0x24/0x90
[   26.296132] el0_svc+0x20/0x30
[   26.299185] el0_sync_handler+0xe8/0xf0
[   26.303018] el0_sync+0x1a4/0x1c0
[   26.306330] irq event stamp: 0
[   26.309384] hardirqs last  enabled at (0): [<0000000000000000>] 0x0
[   26.315650] hardirqs last disabled at (0): [<ffff800010056d34>] copy_process+0x5d0/0x183c
[   26.323825] softirqs last  enabled at (0): [<ffff800010056d34>] copy_process+0x5d0/0x183c
[   26.331997] softirqs last disabled at (0): [<0000000000000000>] 0x0
[   26.338261] ---[ end trace 20ae984fa860184a ]---
[   26.343021] ------------[ cut here ]------------
[   26.347646] WARNING: CPU: 3 PID: 345 at drivers/gpu/drm/drm_modeset_lock.c:228 drm_modeset_drop_locks+0x84/0x90
[   26.357727] Modules linked in:
[   26.360783] CPU: 3 PID: 345 Comm: composer@2.1-se Kdump: loaded Tainted: G   W  5.10.110-SE-SDK1.8-dirty #16
[   26.371645] Hardware name: Siengine Se1000 Evaluation board (DT)
[   26.377647] pstate: 20400009 (nzCv daif +PAN -UAO -TCO BTYPE=--)
[   26.383649] pc : drm_modeset_drop_locks+0x84/0x90
[   26.388351] lr : drm_mode_atomic_ioctl+0x860/0xb8c
[   26.393137] sp : ffff800017b8bb10
[   26.396447] pmr_save: 000000e0
[   26.399497] x29: ffff800017b8bb10 x28: 0000000000000001
[   26.404807] x27: 0000000000000038 x26: 0000000000000002
[   26.410115] x25: ffff000cecbefa00 x24: ffff000cf2f96200
[   26.415423] x23: 0000000000000001 x22: 0000000000000018
[   26.420731] x21: 0000000000000001 x20: ffff800017b8bc10
[   26.426039] x19: 0000000000000000 x18: 0000000000000000
[   26.431347] x17: 0000000002e8bf2c x16: 0000000002e94c6b
[   26.436655] x15: 0000000002ea48b9 x14: ffff8000121f0300
[   26.441963] x13: 0000000002ee2ca8 x12: ffff80001129cae0
[   26.447272] x11: ffff800012435000 x10: ffff000ed46b5e88
[   26.452580] x9 : ffff000c9935e600 x8 : 0000000000000000
[   26.457888] x7 : 000000008020001e x6 : 000000008020001f
[   26.463196] x5 : ffff80001085fbe0 x4 : fffffe0033a59f20
[   26.468504] x3 : 000000008020001e x2 : 0000000000000000
[   26.473813] x1 : 0000000000000000 x0 : ffff000c8f596090
[   26.479122] Call trace:
[   26.481566] drm_modeset_drop_locks+0x84/0x90
[   26.485918] drm_mode_atomic_ioctl+0x860/0xb8c
[   26.490359] drm_ioctl_kernel+0xc4/0x120
[   26.494278] drm_ioctl+0x268/0x534
[   26.497677] __arm64_sys_ioctl+0xa8/0xf0
[   26.501598] el0_svc_common.constprop.0+0x80/0x240
[   26.506384] do_el0_svc+0x24/0x90
[   26.509697] el0_svc+0x20/0x30
[   26.512748] el0_sync_handler+0xe8/0xf0
[   26.516580] el0_sync+0x1a4/0x1c0
[   26.519891] irq event stamp: 0
[   26.522943] hardirqs last  enabled at (0): [<0000000000000000>] 0x0
[   26.529207] hardirqs last disabled at (0): [<ffff800010056d34>] copy_process+0x5d0/0x183c
[   26.537379] softirqs last  enabled at (0): [<ffff800010056d34>] copy_process+0x5d0/0x183c
[   26.545550] softirqs last disabled at (0): [<0000000000000000>] 0x0
[   26.551812] ---[ end trace 20ae984fa860184b ]---

According to the call trace information,it can be located to be
WARN_ON(IS_ERR(c_st)) in the komeda_pipeline_unbound_components function;
Then follow the function.
komeda_pipeline_unbound_components
-> komeda_component_get_state_and_set_user
  -> komeda_pipeline_get_state_and_set_crtc
    -> komeda_pipeline_get_state
      ->drm_atomic_get_private_obj_state
        -> drm_atomic_get_private_obj_state
          -> drm_modeset_lock

komeda_pipeline_unbound_components
-> komeda_component_get_state_and_set_user
  -> komeda_component_get_state
    -> drm_atomic_get_private_obj_state
     -> drm_modeset_lock

ret = drm_modeset_lock(&obj->lock, state->acquire_ctx); if (ret)
	return ERR_PTR(ret);
Here it return -EDEADLK.

deal with the deadlock as suggested by [1], using the
function drm_modeset_backoff().
[1] https://docs.kernel.org/gpu/drm-kms.html?highlight=kms#kms-locking

Therefore, handling this problem can be solved
by adding return -EDEADLK back to the drm_modeset_backoff processing flow
in the drm_mode_atomic_ioctl function.

Signed-off-by: baozhu.liu <lucas.liu@siengine.com>
Signed-off-by: menghui.huang <menghui.huang@siengine.com>
Reviewed-by: Liviu Dudau <liviu.dudau@arm.com>
Signed-off-by: Liviu Dudau <liviu.dudau@arm.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230804013117.6870-1-menghui.huang@siengine.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-11-28 17:06:57 +00:00
arch x86/mm: Drop the 4 MB restriction on minimal NUMA node memory size 2023-11-28 17:06:55 +00:00
block blk-core: use pr_warn_ratelimited() in bio_check_ro() 2023-11-20 11:52:17 +01:00
certs certs: Fix build error when PKCS#11 URI contains semicolon 2023-02-09 11:28:11 +01:00
crypto crypto: lrw,xts - Replace strlcpy with strscpy 2023-09-23 11:11:01 +02:00
Documentation smp,csd: Throw an error if a CSD lock is stuck for too long 2023-11-28 17:06:55 +00:00
drivers drm/komeda: drop all currently held locks if deadlock happens 2023-11-28 17:06:57 +00:00
fs btrfs: use u64 for buffer sizes in the tree search ioctls 2023-11-20 11:52:18 +01:00
include vsock: read from socket's error queue 2023-11-28 17:06:56 +00:00
init sched/psi: Select KERNFS as needed 2023-09-13 09:42:28 +02:00
io_uring io_uring/net: ensure socket is marked connected on connect retry 2023-11-20 11:52:18 +01:00
ipc ipc: fix memory leak in init_mqueue_fs() 2022-12-31 13:32:01 +01:00
kernel bpf: Ensure proper register state printing for cond jumps 2023-11-28 17:06:56 +00:00
lib lib/generic-radix-tree.c: Don't overflow in peek() 2023-11-28 17:06:54 +00:00
LICENSES LICENSES/LGPL-2.1: Add LGPL-2.1-or-later as valid identifiers 2021-12-16 14:33:10 +01:00
mm filemap: add filemap_get_folios_tag() 2023-11-20 11:52:09 +01:00
net Bluetooth: Fix double free in hci_conn_cleanup 2023-11-28 17:06:56 +00:00
rust rust: allocator: Prevent mis-aligned allocation 2023-08-11 12:08:18 +02:00
samples fprobe: Pass entry_data to handlers 2023-10-25 12:03:12 +02:00
scripts modpost: fix ishtp MODULE_DEVICE_TABLE built on big-endian host 2023-11-20 11:52:12 +01:00
security apparmor: fix invalid reference on profile->disconnected 2023-11-20 11:52:09 +01:00
sound ASoC: dapm: fix clock get name 2023-11-20 11:52:18 +01:00
tools selftests/lkdtm: Disable CONFIG_UBSAN_TRAP in test config 2023-11-28 17:06:54 +00:00
usr usr/gen_init_cpio.c: remove unnecessary -1 values from int file 2022-10-03 14:21:44 -07:00
virt kvm/vfio: ensure kvg instance stays around in kvm_vfio_group_add() 2023-09-13 09:42:46 +02:00
.clang-format inet: ping: use hlist_nulls rcu iterator during lookup 2022-12-01 12:42:46 +01:00
.cocciconfig
.get_maintainer.ignore get_maintainer: add Alan to .get_maintainer.ignore 2022-08-20 15:17:44 -07:00
.gitattributes .gitattributes: use 'dts' diff driver for dts files 2019-12-04 19:44:11 -08:00
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.mailmap 9 hotfixes. 6 for MM, 3 for other areas. Four of these patches address 2022-12-10 17:10:52 -08:00
.rustfmt.toml rust: add .rustfmt.toml 2022-09-28 09:02:20 +02:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS MAINTAINERS: Remove Michal Marek from Kbuild maintainers 2022-11-16 14:53:00 +09:00
Kbuild Kbuild updates for v6.1 2022-10-10 12:00:45 -07:00
Kconfig kbuild: ensure full rebuild when the compiler is updated 2020-05-12 13:28:33 +09:00
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Makefile Linux 6.1.63 2023-11-20 11:52:19 +01:00
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