Kernel sources for Moto G9 (Play) (Guamp)
Find a file
Alexis Lothoré f573c3f37b pinctrl: at91-pio4: use dedicated lock class for IRQ
[ Upstream commit 14694179e561b5f2f7e56a0f590e2cb49a9cc7ab ]

Trying to suspend to RAM on SAMA5D27 EVK leads to the following lockdep
warning:

 ============================================
 WARNING: possible recursive locking detected
 6.7.0-rc5-wt+ #532 Not tainted
 --------------------------------------------
 sh/92 is trying to acquire lock:
 c3cf306c (&irq_desc_lock_class){-.-.}-{2:2}, at: __irq_get_desc_lock+0xe8/0x100

 but task is already holding lock:
 c3d7c46c (&irq_desc_lock_class){-.-.}-{2:2}, at: __irq_get_desc_lock+0xe8/0x100

 other info that might help us debug this:
  Possible unsafe locking scenario:

        CPU0
        ----
   lock(&irq_desc_lock_class);
   lock(&irq_desc_lock_class);

  *** DEADLOCK ***

  May be due to missing lock nesting notation

 6 locks held by sh/92:
  #0: c3aa0258 (sb_writers#6){.+.+}-{0:0}, at: ksys_write+0xd8/0x178
  #1: c4c2df44 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x138/0x284
  #2: c32684a0 (kn->active){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x148/0x284
  #3: c232b6d4 (system_transition_mutex){+.+.}-{3:3}, at: pm_suspend+0x13c/0x4e8
  #4: c387b088 (&dev->mutex){....}-{3:3}, at: __device_suspend+0x1e8/0x91c
  #5: c3d7c46c (&irq_desc_lock_class){-.-.}-{2:2}, at: __irq_get_desc_lock+0xe8/0x100

 stack backtrace:
 CPU: 0 PID: 92 Comm: sh Not tainted 6.7.0-rc5-wt+ #532
 Hardware name: Atmel SAMA5
  unwind_backtrace from show_stack+0x18/0x1c
  show_stack from dump_stack_lvl+0x34/0x48
  dump_stack_lvl from __lock_acquire+0x19ec/0x3a0c
  __lock_acquire from lock_acquire.part.0+0x124/0x2d0
  lock_acquire.part.0 from _raw_spin_lock_irqsave+0x5c/0x78
  _raw_spin_lock_irqsave from __irq_get_desc_lock+0xe8/0x100
  __irq_get_desc_lock from irq_set_irq_wake+0xa8/0x204
  irq_set_irq_wake from atmel_gpio_irq_set_wake+0x58/0xb4
  atmel_gpio_irq_set_wake from irq_set_irq_wake+0x100/0x204
  irq_set_irq_wake from gpio_keys_suspend+0xec/0x2b8
  gpio_keys_suspend from dpm_run_callback+0xe4/0x248
  dpm_run_callback from __device_suspend+0x234/0x91c
  __device_suspend from dpm_suspend+0x224/0x43c
  dpm_suspend from dpm_suspend_start+0x9c/0xa8
  dpm_suspend_start from suspend_devices_and_enter+0x1e0/0xa84
  suspend_devices_and_enter from pm_suspend+0x460/0x4e8
  pm_suspend from state_store+0x78/0xe4
  state_store from kernfs_fop_write_iter+0x1a0/0x284
  kernfs_fop_write_iter from vfs_write+0x38c/0x6f4
  vfs_write from ksys_write+0xd8/0x178
  ksys_write from ret_fast_syscall+0x0/0x1c
 Exception stack(0xc52b3fa8 to 0xc52b3ff0)
 3fa0:                   00000004 005a0ae8 00000001 005a0ae8 00000004 00000001
 3fc0: 00000004 005a0ae8 00000001 00000004 00000004 b6c616c0 00000020 0059d190
 3fe0: 00000004 b6c61678 aec5a041 aebf1a26

This warning is raised because pinctrl-at91-pio4 uses chained IRQ. Whenever
a wake up source configures an IRQ through irq_set_irq_wake, it will
lock the corresponding IRQ desc, and then call irq_set_irq_wake on "parent"
IRQ which will do the same on its own IRQ desc, but since those two locks
share the same class, lockdep reports this as an issue.

Fix lockdep false positive by setting a different class for parent and
children IRQ

Fixes: 776180848b ("pinctrl: introduce driver for Atmel PIO4 controller")
Signed-off-by: Alexis Lothoré <alexis.lothore@bootlin.com>
Link: https://lore.kernel.org/r/20231215-lockdep_warning-v1-1-8137b2510ed5@bootlin.com
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-01-08 11:27:34 +01:00
arch s390/vx: fix save/restore of fpu kernel context 2024-01-08 11:27:33 +01:00
block blk-throttle: fix lockdep warning of "cgroup_mutex or RCU read lock required!" 2023-12-20 15:38:02 +01:00
certs certs/blacklist_hashes.c: fix const confusion in certs blacklist 2022-06-25 11:49:16 +02:00
crypto crypto: pcrypt - Fix hungtask for PADATA_RESET 2023-11-28 16:46:31 +00:00
Documentation Documentation: security-bugs.rst: clarify CVE handling 2023-08-11 11:45:34 +02:00
drivers pinctrl: at91-pio4: use dedicated lock class for IRQ 2024-01-08 11:27:34 +01:00
firmware Fix built-in early-load Intel microcode alignment 2020-01-23 08:21:29 +01:00
fs afs: Fix the dynamic root's d_delete to always delete unused dentries 2024-01-08 11:27:34 +01:00
include asm-generic: qspinlock: fix queued_spin_value_unlocked() implementation 2023-12-20 15:38:03 +01:00
init init, x86: Move mem_encrypt_init() into arch_cpu_finalize_init() 2023-08-08 19:49:18 +02:00
ipc ipc/sem: Fix dangling sem_array access in semtimedop race 2022-12-08 11:18:35 +01:00
kernel ring-buffer: Fix memory leak of free page 2023-12-20 15:38:03 +01:00
lib kobject: Fix slab-out-of-bounds in fill_kobj_path() 2023-11-08 11:22:17 +01:00
LICENSES LICENSES: Remove CC-BY-SA-4.0 license text 2018-10-18 11:28:50 +02:00
mm vfs: fix readahead(2) on block devices 2023-11-20 10:29:16 +01:00
net net: check dev->gso_max_size in gso_features_check() 2024-01-08 11:27:34 +01:00
samples samples/bpf: Fix buffer overflow in tcp_basertt 2023-08-11 11:45:03 +02:00
scripts sign-file: Fix incorrect return values check 2023-12-20 15:38:01 +01:00
security ima: detect changes to the backing overlay file 2023-12-08 08:43:26 +01:00
sound ALSA: hda/realtek: Enable headset on Lenovo M90 Gen5 2024-01-08 11:27:33 +01:00
tools tools headers UAPI: Sync linux/perf_event.h with the kernel sources 2023-12-13 17:42:20 +01:00
usr initramfs: restore default compression behavior 2020-04-13 10:44:59 +02:00
virt KVM: arm64: vgic: Fix exit condition in scan_its_table() 2022-11-03 23:52:24 +09:00
.clang-format clang-format: Set IndentWrappedFunctionNames false 2018-08-01 18:38:51 +02:00
.cocciconfig
.get_maintainer.ignore
.gitattributes .gitattributes: set git diff driver for C source code files 2016-10-07 18:46:30 -07:00
.gitignore Kbuild updates for v4.17 (2nd) 2018-04-15 17:21:30 -07:00
.mailmap libnvdimm-for-4.19_misc 2018-08-25 18:13:10 -07:00
COPYING COPYING: use the new text with points to the license files 2018-03-23 12:41:45 -06:00
CREDITS 9p: remove Ron Minnich from MAINTAINERS 2018-08-17 16:20:26 -07:00
Kbuild Kbuild updates for v4.15 2017-11-17 17:45:29 -08:00
Kconfig kconfig: move the "Executable file formats" menu to fs/Kconfig.binfmt 2018-08-02 08:06:55 +09:00
MAINTAINERS MAINTAINERS: r8169: Update path to the driver 2023-11-08 11:22:19 +01:00
Makefile Linux 4.19.303 2023-12-20 15:38:04 +01:00
README Docs: Added a pointer to the formatted docs to README 2018-03-21 09:02:53 -06:00

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
See Documentation/00-INDEX for a list of what is contained in each file.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.