[PATCH] drivers/core: Remove lockdep_set_novalidate_class() usage

From: Tetsuo Handa
Date: Mon Jan 23 2023 - 05:32:26 EST

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This patch experimentally removes lockdep_set_novalidate_class() call
from device_initialize() introduced by commit 1704f47b50b5 ("lockdep:
Add novalidate class for dev->mutex conversion"), for this commit made it
impossible to find real deadlocks unless timing dependent testings manage
to trigger hung task like [1] and [2]. Let's try if we can find remaining
drivers which need to use separate classes without causing too many crashes
to continue.

[1] https://syzkaller.appspot.com/bug?extid=2d6ac90723742279e101
[2] https://syzkaller.appspot.com/bug?extid=2e39bc6569d281acbcfb

Signed-off-by: Tetsuo Handa <penguin-kernel@xxxxxxxxxxxxxxxxxxx>
---
drivers/base/core.c | 1 -
1 file changed, 1 deletion(-)

diff --git a/drivers/base/core.c b/drivers/base/core.c
index a3e14143ec0c..68189722e343 100644
--- a/drivers/base/core.c
+++ b/drivers/base/core.c
@@ -2941,7 +2941,6 @@ void device_initialize(struct device *dev)
kobject_init(&dev->kobj, &device_ktype);
INIT_LIST_HEAD(&dev->dma_pools);
mutex_init(&dev->mutex);
- lockdep_set_novalidate_class(&dev->mutex);
spin_lock_init(&dev->devres_lock);
INIT_LIST_HEAD(&dev->devres_head);
device_pm_init(dev);
--
2.18.4
----------

----------
[ 2.241650][ T9] Trying to unpack rootfs image as initramfs...
[ 2.241630][ T1] software IO TLB: mapped [mem 0x00000000bbed0000-0x00000000bfed0000] (64MB)
[ 2.241670][ T1] workingset: timestamp_bits=46 max_order=21 bucket_order=0
[ 2.241670][ T1] SGI XFS with ACLs, security attributes, verbose warnings, quota, no debug enabled
[ 2.241670][ T1] Block layer SCSI generic (bsg) driver version 0.4 loaded (major 252)
[ 2.798150][ T1]
[ 2.798660][ T1] ======================================================
[ 2.798660][ T1] WARNING: possible circular locking dependency detected
[ 2.798660][ T1] 6.2.0-rc5+ #9 Not tainted
[ 2.798660][ T1] ------------------------------------------------------
[ 2.798660][ T1] swapper/0/1 is trying to acquire lock:
[ 2.798660][ T1] ffffffffb002e888 (cpu_add_remove_lock){+.+.}-{3:3}, at: cpu_hotplug_disable+0x12/0x30
[ 2.798660][ T1]
[ 2.798660][ T1] but task is already holding lock:
[ 2.798660][ T1] ffff941940a161b8 (&dev->mutex){+.+.}-{3:3}, at: __device_driver_lock+0x28/0x40
[ 2.798660][ T1]
[ 2.798660][ T1] which lock already depends on the new lock.
[ 2.798660][ T1]
[ 2.798660][ T1]
[ 2.798660][ T1] the existing dependency chain (in reverse order) is:
[ 2.798660][ T1]
[ 2.798660][ T1] -> #3 (&dev->mutex){+.+.}-{3:3}:
[ 2.798660][ T1] lock_acquire+0xc7/0x2e0
[ 2.798660][ T1] __mutex_lock+0x99/0xf00
[ 2.798660][ T1] mutex_lock_nested+0x16/0x20
[ 2.798660][ T1] __device_attach+0x35/0x1a0
[ 2.798660][ T1] device_initial_probe+0xe/0x10
[ 2.798660][ T1] bus_probe_device+0x9b/0xb0
[ 2.798660][ T1] device_add+0x3e1/0x900
[ 2.798660][ T1] pmu_dev_alloc+0x98/0xf0
[ 2.798660][ T1] perf_event_sysfs_init+0x56/0x8f
[ 2.798660][ T1] do_one_initcall+0x58/0x300
[ 2.798660][ T1] kernel_init_freeable+0x181/0x1d2
[ 2.798660][ T1] kernel_init+0x15/0x120
[ 2.798660][ T1] ret_from_fork+0x1f/0x30
[ 2.798660][ T1]
[ 2.798660][ T1] -> #2 (pmus_lock){+.+.}-{3:3}:
[ 2.798660][ T1] lock_acquire+0xc7/0x2e0
[ 2.798660][ T1] __mutex_lock+0x99/0xf00
[ 2.798660][ T1] mutex_lock_nested+0x16/0x20
[ 2.798660][ T1] perf_event_init_cpu+0x4c/0x110
[ 2.798660][ T1] cpuhp_invoke_callback+0x17a/0x880
[ 2.798660][ T1] __cpuhp_invoke_callback_range+0x77/0xb0
[ 2.798660][ T1] _cpu_up+0xdc/0x240
[ 2.798660][ T1] cpu_up+0x8c/0xa0
[ 2.798660][ T1] bringup_nonboot_cpus+0x56/0x60
[ 2.798660][ T1] smp_init+0x25/0x5f
[ 2.798660][ T1] kernel_init_freeable+0xb4/0x1d2
[ 2.798660][ T1] kernel_init+0x15/0x120
[ 2.798660][ T1] ret_from_fork+0x1f/0x30
[ 2.798660][ T1]
[ 2.798660][ T1] -> #1 (cpu_hotplug_lock){++++}-{0:0}:
[ 2.798660][ T1] lock_acquire+0xc7/0x2e0
[ 2.798660][ T1] percpu_down_write+0x44/0x2c0
[ 2.798660][ T1] _cpu_up+0x35/0x240
[ 2.798660][ T1] cpu_up+0x8c/0xa0
[ 2.798660][ T1] bringup_nonboot_cpus+0x56/0x60
[ 2.798660][ T1] smp_init+0x25/0x5f
[ 2.798660][ T1] kernel_init_freeable+0xb4/0x1d2
[ 2.798660][ T1] kernel_init+0x15/0x120
[ 2.798660][ T1] ret_from_fork+0x1f/0x30
[ 2.798660][ T1]
[ 2.798660][ T1] -> #0 (cpu_add_remove_lock){+.+.}-{3:3}:
[ 2.798660][ T1] check_prevs_add+0x16a/0x1070
[ 2.798660][ T1] __lock_acquire+0x11bd/0x1670
[ 2.798660][ T1] lock_acquire+0xc7/0x2e0
[ 2.798660][ T1] __mutex_lock+0x99/0xf00
[ 2.798660][ T1] mutex_lock_nested+0x16/0x20
[ 2.798660][ T1] cpu_hotplug_disable+0x12/0x30
[ 2.798660][ T1] pci_device_probe+0x8c/0x150
[ 2.798660][ T1] really_probe+0xd9/0x340
[ 2.798660][ T1] __driver_probe_device+0x78/0x170
[ 2.798660][ T1] driver_probe_device+0x1f/0x90
[ 2.798660][ T1] __driver_attach+0xaa/0x160
[ 2.798660][ T1] bus_for_each_dev+0x75/0xb0
[ 2.798660][ T1] driver_attach+0x19/0x20
[ 2.798660][ T1] bus_add_driver+0x1be/0x210
[ 2.798660][ T1] driver_register+0x6b/0xc0
[ 2.798660][ T1] __pci_register_driver+0x7c/0x80
[ 2.798660][ T1] pcie_portdrv_init+0x3d/0x45
[ 2.798660][ T1] do_one_initcall+0x58/0x300
[ 2.798660][ T1] kernel_init_freeable+0x181/0x1d2
[ 2.798660][ T1] kernel_init+0x15/0x120
[ 2.798660][ T1] ret_from_fork+0x1f/0x30
[ 2.798660][ T1]
[ 2.798660][ T1] other info that might help us debug this:
[ 2.798660][ T1]
[ 2.798660][ T1] Chain exists of:
[ 2.798660][ T1] cpu_add_remove_lock --> pmus_lock --> &dev->mutex
[ 2.798660][ T1]
[ 2.798660][ T1] Possible unsafe locking scenario:
[ 2.798660][ T1]
[ 2.798660][ T1] CPU0 CPU1
[ 2.798660][ T1] ---- ----
[ 2.798660][ T1] lock(&dev->mutex);
[ 2.798660][ T1] lock(pmus_lock);
[ 2.798660][ T1] lock(&dev->mutex);
[ 2.798660][ T1] lock(cpu_add_remove_lock);
[ 2.798660][ T1]
[ 2.798660][ T1] *** DEADLOCK ***
[ 2.798660][ T1]
[ 2.798660][ T1] 1 lock held by swapper/0/1:
[ 2.798660][ T1] #0: ffff941940a161b8 (&dev->mutex){+.+.}-{3:3}, at: __device_driver_lock+0x28/0x40
[ 2.798660][ T1]
[ 2.798660][ T1] stack backtrace:
[ 2.798660][ T1] CPU: 3 PID: 1 Comm: swapper/0 Not tainted 6.2.0-rc5+ #9
[ 2.798660][ T1] Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 11/12/2020
[ 2.798660][ T1] Call Trace:
[ 2.798660][ T1] <TASK>
[ 2.798660][ T1] dump_stack_lvl+0x49/0x5e
[ 2.798660][ T1] dump_stack+0x10/0x12
[ 2.798660][ T1] print_circular_bug.isra.46.cold.66+0x13e/0x143
[ 2.798660][ T1] check_noncircular+0xfe/0x110
[ 2.798660][ T1] check_prevs_add+0x16a/0x1070
[ 2.798660][ T1] __lock_acquire+0x11bd/0x1670
[ 2.798660][ T1] lock_acquire+0xc7/0x2e0
[ 2.798660][ T1] ? cpu_hotplug_disable+0x12/0x30
[ 2.798660][ T1] __mutex_lock+0x99/0xf00
[ 2.798660][ T1] ? cpu_hotplug_disable+0x12/0x30
[ 2.798660][ T1] ? pci_match_device+0xd5/0x130
[ 2.798660][ T1] ? __this_cpu_preempt_check+0x13/0x20
[ 2.798660][ T1] ? cpu_hotplug_disable+0x12/0x30
[ 2.798660][ T1] ? kernfs_add_one+0xf1/0x130
[ 2.798660][ T1] mutex_lock_nested+0x16/0x20
[ 2.798660][ T1] ? mutex_lock_nested+0x16/0x20
[ 2.798660][ T1] cpu_hotplug_disable+0x12/0x30
[ 2.798660][ T1] pci_device_probe+0x8c/0x150
[ 2.798660][ T1] really_probe+0xd9/0x340
[ 2.798660][ T1] ? pm_runtime_barrier+0x52/0xb0
[ 2.798660][ T1] __driver_probe_device+0x78/0x170
[ 2.798660][ T1] driver_probe_device+0x1f/0x90
[ 2.798660][ T1] __driver_attach+0xaa/0x160
[ 2.798660][ T1] ? __device_attach_driver+0x100/0x100
[ 2.798660][ T1] bus_for_each_dev+0x75/0xb0
[ 2.798660][ T1] driver_attach+0x19/0x20
[ 2.798660][ T1] bus_add_driver+0x1be/0x210
[ 2.798660][ T1] ? dmi_pcie_pme_disable_msi+0x1f/0x1f
[ 2.798660][ T1] ? dmi_pcie_pme_disable_msi+0x1f/0x1f
[ 2.798660][ T1] ? rdinit_setup+0x27/0x27
[ 2.798660][ T1] driver_register+0x6b/0xc0
[ 2.798660][ T1] ? dmi_pcie_pme_disable_msi+0x1f/0x1f
[ 2.798660][ T1] __pci_register_driver+0x7c/0x80
[ 2.798660][ T1] pcie_portdrv_init+0x3d/0x45
[ 2.798660][ T1] do_one_initcall+0x58/0x300
[ 2.798660][ T1] ? rdinit_setup+0x27/0x27
[ 2.798660][ T1] ? rcu_read_lock_sched_held+0x4a/0x70
[ 2.798660][ T1] kernel_init_freeable+0x181/0x1d2
[ 2.798660][ T1] ? rest_init+0x190/0x190
[ 2.798660][ T1] kernel_init+0x15/0x120
[ 2.798660][ T1] ret_from_fork+0x1f/0x30
[ 2.798660][ T1] </TASK>
[ 3.991673][ T92] tsc: Refined TSC clocksource calibration: 2611.210 MHz
[ 3.991673][ T92] clocksource: tsc: mask: 0xffffffffffffffff max_cycles: 0x25a399d04c4, max_idle_ns: 440795206293 ns
[ 4.992946][ T92] clocksource: Switched to clocksource tsc
----------

Next message: Bartosz Golaszewski: "[PATCH] clk: qcom: gcc-sa8775p: remove unused variables"
Previous message: Christian.Gromm: "Re: [PATCH] most: fix kernel-doc warnings"
Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]