[GIT PULL] orphaned patches for 6.11

From: Tetsuo Handa
Date: Wed Jul 17 2024 - 06:08:57 EST

The following changes since commit 771ed66105de9106a6f3e4311e06451881cdac5e:

Merge tag 'clk-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux (2024-06-08 19:14:02 -0700)

are available in the Git repository at:

git://git.code.sf.net/p/tomoyo/tomoyo.git tags/misc-pr-20240717

for you to fetch changes up to 92295a0cacb6d2888ca6a6d07cfd007a5dfe1ebf:

Input: MT - limit max slots (2024-06-09 13:19:12 +0900)

----------------------------------------------------------------
These are two of orphaned patches which nobody can take (and as a result
bugs remain unfixed for years). These patches have been tested using
linux-next tree via my tomoyo tree since 20240611, and nobody found problems.

----------------------------------------------------------------
Tetsuo Handa (2):
profiling: initialize prof_cpu_mask from profile_online_cpu()
Input: MT - limit max slots

drivers/input/input-mt.c | 3 +++
kernel/ksysfs.c | 27 ++++++++++++++++++++++-----
kernel/profile.c | 6 +++---
3 files changed, 28 insertions(+), 8 deletions(-)



By the way, there remains a bug which this pull request does not address.
Either booting with

profile=sleep

kernel command line option added or executing

# echo -n sleep > /sys/kernel/profiling

after boot causes the system to lock up.

I've reported this problem at
https://lkml.kernel.org/r/60011cc3-b9fc-49c8-b0c0-35aafe46f313@xxxxxxxxxxxxxxxxxxx
but nobody was interested in. Can somebody test this problem using real hardware?
If this problem happens with real hardware, maybe nobody is using "kernel sleep
profiling" and we can remove "kernel sleep profiling" functionality.



Booting with profile=sleep added:
----------------------------------------
[ 7.254439] kernel profiling enabled schedstats, disable via kernel.sched_schedstats.
[ 7.254514] kernel sleep profiling enabled (shift: 0)
(...snipped...)
[ 13.334555] smpboot: CPU0: 12th Gen Intel(R) Core(TM) i7-1255U (family: 0x6, model: 0x9a, stepping: 0x4)
[ 13.337444]
[ 13.337857] ============================================
[ 13.337857] WARNING: possible recursive locking detected
[ 13.337857] 6.10.0 #95 Not tainted
[ 13.337857] --------------------------------------------
[ 13.337857] swapper/0/1 is trying to acquire lock:
[ 13.337857] ffff8a1784955d38 (&p->pi_lock){....}-{2:2}, at: get_wchan+0x32/0x80
[ 13.337857]
[ 13.337857] but task is already holding lock:
[ 13.337857] ffff8a1784955d38 (&p->pi_lock){....}-{2:2}, at: try_to_wake_up+0x54/0x5f0
[ 13.337857]
[ 13.337857] other info that might help us debug this:
[ 13.337857] Possible unsafe locking scenario:
[ 13.337857]
[ 13.337857] CPU0
[ 13.337857] ----
[ 13.337857] lock(&p->pi_lock);
[ 13.337857] lock(&p->pi_lock);
[ 13.337857]
[ 13.337857] *** DEADLOCK ***
[ 13.337857]
[ 13.337857] May be due to missing lock nesting notation
[ 13.337857]
[ 13.337857] 2 locks held by swapper/0/1:
[ 13.337857] #0: ffff8a1784955d38 (&p->pi_lock){....}-{2:2}, at: try_to_wake_up+0x54/0x5f0
[ 13.337857] #1: ffff8a1819ff7dd8 (&rq->__lock){-.-.}-{2:2}, at: try_to_wake_up+0x16c/0x5f0
[ 13.337857]
[ 13.337857] stack backtrace:
[ 13.337857] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 6.10.0 #95
[ 13.337857] Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 11/12/2020
[ 13.337857] Call Trace:
[ 13.337857] <TASK>
[ 13.337857] dump_stack_lvl+0x79/0xb0
[ 13.337857] validate_chain+0x300/0x4c0
[ 13.337857] __lock_acquire+0x51f/0xb90
[ 13.337857] lock_acquire.part.0+0x6e/0x1c0
[ 13.337857] ? get_wchan+0x32/0x80
[ 13.337857] ? lock_acquire+0xf4/0x130
[ 13.337857] ? get_wchan+0x32/0x80
[ 13.337857] __raw_spin_lock_irq+0x40/0x90
[ 13.337857] ? get_wchan+0x32/0x80
[ 13.337857] get_wchan+0x32/0x80
[ 13.337857] __update_stats_enqueue_sleeper+0x153/0x380
[ 13.337857] enqueue_entity+0x42b/0x580
[ 13.337857] enqueue_task_fair+0x97/0x3d0
[ 13.337857] activate_task+0x4e/0xe0
[ 13.337857] ttwu_do_activate+0x5d/0x2a0
[ 13.337857] try_to_wake_up+0x1cf/0x5f0
[ 13.337857] ? __wait_for_common+0x4d/0x220
[ 13.337857] __kthread_create_worker+0xab/0x100
[ 13.337857] kthread_create_worker+0x61/0x80
[ 13.337857] workqueue_init+0x1d/0x390
[ 13.337857] kernel_init_freeable+0xc4/0x230
[ 13.337857] ? __pfx_kernel_init+0x10/0x10
[ 13.337857] kernel_init+0x1a/0x1d0
[ 13.337857] ret_from_fork+0x31/0x50
[ 13.337857] ? __pfx_kernel_init+0x10/0x10
[ 13.337857] ret_from_fork_asm+0x1a/0x30
[ 13.337857] </TASK>
----------------------------------------

Writing to /sys/kernel/profiling after boot:
----------------------------------------
[ 69.085956] kernel profiling enabled schedstats, disable via kernel.sched_schedstats.
[ 69.096289] kernel sleep profiling enabled (shift: 0)
[ 69.102141]
[ 69.105003] ======================================================
[ 69.111960] WARNING: possible circular locking dependency detected
[ 69.118765] 6.10.0 #95 Not tainted
[ 69.122478] ------------------------------------------------------
[ 69.128995] swapper/2/0 is trying to acquire lock:
[ 69.134270] ffff94bac09cb5b8 (&p->pi_lock){-.-.}-{2:2}, at: get_wchan+0x32/0x80
[ 69.141938]
[ 69.141938] but task is already holding lock:
[ 69.148104] ffff94bb5a7f7dd8 (&rq->__lock){-.-.}-{2:2}, at: _raw_spin_rq_lock_irqsave+0x2c/0x50
[ 69.157339]
[ 69.157339] which lock already depends on the new lock.
[ 69.157339]
[ 69.165841]
[ 69.165841] the existing dependency chain (in reverse order) is:
[ 69.173805]
[ 69.173805] -> #1 (&rq->__lock){-.-.}-{2:2}:
[ 69.180186] __lock_acquire+0x51f/0xb90
[ 69.184799] lock_acquire.part.0+0x6e/0x1c0
[ 69.190031] _raw_spin_lock_nested+0x33/0x80
[ 69.195285] raw_spin_rq_lock_nested+0x15/0x30
[ 69.200854] task_fork_fair+0x3e/0xe0
[ 69.206084] sched_cgroup_fork+0x11e/0x160
[ 69.211425] copy_process+0x12d6/0x1c70
[ 69.216385] kernel_clone+0x9e/0x390
[ 69.220996] user_mode_thread+0x5f/0x90
[ 69.225841] rest_init+0x1e/0x190
[ 69.230291] start_kernel+0x5d6/0x6a0
[ 69.235052] x86_64_start_reservations+0x18/0x30
[ 69.240660] x86_64_start_kernel+0x92/0xa0
[ 69.245837] common_startup_64+0x13e/0x141
[ 69.250905]
[ 69.250905] -> #0 (&p->pi_lock){-.-.}-{2:2}:
[ 69.257221] check_prev_add+0xf1/0xce0
[ 69.262034] validate_chain+0x406/0x4c0
[ 69.266893] __lock_acquire+0x51f/0xb90
[ 69.271676] lock_acquire.part.0+0x6e/0x1c0
[ 69.276901] __raw_spin_lock_irq+0x40/0x90
[ 69.281950] get_wchan+0x32/0x80
[ 69.286109] __update_stats_enqueue_sleeper+0x153/0x380
[ 69.292413] enqueue_entity+0x42b/0x580
[ 69.297274] enqueue_task_fair+0x97/0x3d0
[ 69.302301] activate_task+0x4e/0xe0
[ 69.306790] ttwu_do_activate+0x5d/0x2a0
[ 69.311689] sched_ttwu_pending+0xe7/0x1a0
[ 69.316756] __flush_smp_call_function_queue+0x1d9/0x690
[ 69.323108] __sysvec_call_function_single+0x3c/0x150
[ 69.329181] sysvec_call_function_single+0x68/0x90
[ 69.334953] asm_sysvec_call_function_single+0x1a/0x20
[ 69.341089] pv_native_safe_halt+0xf/0x20
[ 69.346141] acpi_safe_halt+0x14/0x20
[ 69.350757] acpi_idle_enter+0x83/0xd0
[ 69.355541] cpuidle_enter_state+0xcb/0x550
[ 69.360770] cpuidle_enter+0x2d/0x40
[ 69.365292] cpuidle_idle_call+0xf4/0x160
[ 69.370263] do_idle+0x96/0xf0
[ 69.374282] cpu_startup_entry+0x29/0x30
[ 69.379178] start_secondary+0x121/0x140
[ 69.384062] common_startup_64+0x13e/0x141
[ 69.389210]
[ 69.389210] other info that might help us debug this:
[ 69.389210]
[ 69.397778] Possible unsafe locking scenario:
[ 69.397778]
[ 69.404212] CPU0 CPU1
[ 69.409217] ---- ----
[ 69.414230] lock(&rq->__lock);
[ 69.417973] lock(&p->pi_lock);
[ 69.424200] lock(&rq->__lock);
[ 69.430373] lock(&p->pi_lock);
[ 69.434115]
[ 69.434115] *** DEADLOCK ***
[ 69.434115]
[ 69.440608] 1 lock held by swapper/2/0:
[ 69.444875] #0: ffff94bb5a7f7dd8 (&rq->__lock){-.-.}-{2:2}, at: _raw_spin_rq_lock_irqsave+0x2c/0x50
[ 69.454596]
[ 69.454596] stack backtrace:
[ 69.459437] CPU: 2 PID: 0 Comm: swapper/2 Kdump: loaded Not tainted 6.10.0 #95
[ 69.467336] Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 11/12/2020
[ 69.478770] Call Trace:
[ 69.481622] <IRQ>
[ 69.484047] dump_stack_lvl+0x79/0xb0
[ 69.488303] check_noncircular+0x133/0x150
[ 69.492874] ? lock_is_held_type+0xaf/0x130
[ 69.497547] ? update_sd_lb_stats.constprop.0+0x284/0x2d0
[ 69.503424] check_prev_add+0xf1/0xce0
[ 69.507613] ? add_chain_cache+0x111/0x310
[ 69.512100] validate_chain+0x406/0x4c0
[ 69.516327] __lock_acquire+0x51f/0xb90
[ 69.520523] lock_acquire.part.0+0x6e/0x1c0
[ 69.525068] ? get_wchan+0x32/0x80
[ 69.528858] ? lock_acquire+0xf4/0x130
[ 69.533053] ? get_wchan+0x32/0x80
[ 69.536923] __raw_spin_lock_irq+0x40/0x90
[ 69.541444] ? get_wchan+0x32/0x80
[ 69.545240] get_wchan+0x32/0x80
[ 69.548942] __update_stats_enqueue_sleeper+0x153/0x380
[ 69.554443] enqueue_entity+0x42b/0x580
[ 69.558693] enqueue_task_fair+0x97/0x3d0
[ 69.563127] activate_task+0x4e/0xe0
[ 69.567123] ttwu_do_activate+0x5d/0x2a0
[ 69.571500] sched_ttwu_pending+0xe7/0x1a0
[ 69.576099] __flush_smp_call_function_queue+0x1d9/0x690
[ 69.581823] __sysvec_call_function_single+0x3c/0x150
[ 69.587257] sysvec_call_function_single+0x68/0x90
[ 69.592491] </IRQ>
[ 69.595084] <TASK>
[ 69.597586] asm_sysvec_call_function_single+0x1a/0x20
[ 69.603105] RIP: 0010:pv_native_safe_halt+0xf/0x20
[ 69.608395] Code: 22 d7 c3 cc cc cc cc 0f 1f 40 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa eb 07 0f 00 2d 65 3f 3e 00 fb f4 <c3> cc cc cc cc 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90
[ 69.627892] RSP: 0018:ffffb58b000efe50 EFLAGS: 00000246
[ 69.633594] RAX: 0000000000004000 RBX: 0000000000000001 RCX: 0000000000000000
[ 69.641202] RDX: ffff94bb5a600000 RSI: ffff94bb79020800 RDI: ffff94bb79020864
[ 69.648787] RBP: ffff94bb79020864 R08: ffffffff96b63420 R09: 0000000000000000
[ 69.656489] R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000001
[ 69.663706] R13: ffffffff96b634a0 R14: 0000000000000001 R15: 00000000001f6a0c
[ 69.671313] acpi_safe_halt+0x14/0x20
[ 69.675411] acpi_idle_enter+0x83/0xd0
[ 69.679550] cpuidle_enter_state+0xcb/0x550
[ 69.684224] cpuidle_enter+0x2d/0x40
[ 69.688203] cpuidle_idle_call+0xf4/0x160
[ 69.692204] do_idle+0x96/0xf0
[ 69.695673] cpu_startup_entry+0x29/0x30
[ 69.699998] start_secondary+0x121/0x140
[ 69.704366] common_startup_64+0x13e/0x141
[ 69.708374] </TASK>
----------------------------------------