John Ogness e37577ebbf printk: Fail pr_flush() if before SYSTEM_SCHEDULING ...

A follow-up change adds pr_flush() to console unregistration.
However, with boot consoles unregistration can happen very
early if there are also regular consoles registering as well.
In this case the pr_flush() is not important because all
consoles are flushed when checking the initial console sequence
number.

Allow pr_flush() to fail if @system_state has not yet reached
SYSTEM_SCHEDULING. This avoids might_sleep() and msleep()
explosions that would otherwise occur:

[    0.436739][    T0] printk: legacy console [ttyS0] enabled
[    0.439820][    T0] printk: legacy bootconsole [earlyser0] disabled
[    0.446822][    T0] BUG: scheduling while atomic: swapper/0/0/0x00000002
[    0.450491][    T0] 1 lock held by swapper/0/0:
[    0.457897][    T0]  #0: ffffffff82ae5f88 (console_mutex){+.+.}-{4:4}, at: console_list_lock+0x20/0x70
[    0.463141][    T0] Modules linked in:
[    0.465307][    T0] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 6.10.0-rc1+ #372
[    0.469394][    T0] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.14.0-2 04/01/2014
[    0.474402][    T0] Call Trace:
[    0.476246][    T0]  <TASK>
[    0.481473][    T0]  dump_stack_lvl+0x93/0xb0
[    0.483949][    T0]  dump_stack+0x10/0x20
[    0.486256][    T0]  __schedule_bug+0x68/0x90
[    0.488753][    T0]  __schedule+0xb9b/0xd80
[    0.491179][    T0]  ? lock_release+0xb5/0x270
[    0.493732][    T0]  schedule+0x43/0x170
[    0.495998][    T0]  schedule_timeout+0xc5/0x1e0
[    0.498634][    T0]  ? __pfx_process_timeout+0x10/0x10
[    0.501522][    T0]  ? msleep+0x13/0x50
[    0.503728][    T0]  msleep+0x3c/0x50
[    0.505847][    T0]  __pr_flush.constprop.0.isra.0+0x56/0x500
[    0.509050][    T0]  ? _printk+0x58/0x80
[    0.511332][    T0]  ? lock_is_held_type+0x9c/0x110
[    0.514106][    T0]  unregister_console_locked+0xe1/0x450
[    0.517144][    T0]  register_console+0x509/0x620
[    0.519827][    T0]  ? __pfx_univ8250_console_init+0x10/0x10
[    0.523042][    T0]  univ8250_console_init+0x24/0x40
[    0.525845][    T0]  console_init+0x43/0x210
[    0.528280][    T0]  start_kernel+0x493/0x980
[    0.530773][    T0]  x86_64_start_reservations+0x18/0x30
[    0.533755][    T0]  x86_64_start_kernel+0xae/0xc0
[    0.536473][    T0]  common_startup_64+0x12c/0x138
[    0.539210][    T0]  </TASK>

And then the kernel goes into an infinite loop complaining about:

1. releasing a pinned lock
2. unpinning an unpinned lock
3. bad: scheduling from the idle thread!
4. goto 1

Signed-off-by: John Ogness <john.ogness@linutronix.de>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20240904120536.115780-3-john.ogness@linutronix.de
Signed-off-by: Petr Mladek <pmladek@suse.com>

2024-09-04 15:56:32 +02:00

..

bpf

bpf: Fix a kernel verifier crash in stacksafe()

2024-08-12 18:09:48 -07:00

cgroup

Merge branch 'for-6.10-fixes' into for-6.11

2024-07-14 18:04:03 -10:00

configs

mm/slab: Plumb kmem_buckets into __do_kmalloc_node()

2024-07-03 12:24:19 +02:00

debug

kdb: Get rid of redundant kdb_curr_task()

2024-06-21 15:49:29 +01:00

dma

dma-debug: avoid deadlock between dma debug vs printk and netconsole

2024-08-06 10:29:32 -07:00

entry

entry: Respect changes to system call number by trace_sys_enter()

2024-03-12 13:23:32 +01:00

events

perf/bpf: Don't call bpf_overflow_handler() for tracing events

2024-08-13 10:25:28 -07:00

futex

printk: Change type of CONFIG_BASE_SMALL to bool

2024-05-06 17:39:09 +02:00

gcov

gcov: add support for GCC 14

2024-06-15 10:43:06 -07:00

irq

genirq/irqdesc: Honor caller provided affinity in alloc_desc()

2024-08-07 17:27:00 +02:00

kcsan

kcsan: Add missing MODULE_DESCRIPTION() macro

2024-06-06 11:21:14 -07:00

livepatch

livepatch: Replace snprintf() with sysfs_emit()

2024-07-02 16:56:18 +02:00

locking

lockdep: Mark emergency sections in lockdep splats

2024-08-21 15:03:04 +02:00

module

module: make waiting for a concurrent module loader interruptible

2024-08-09 08:33:28 -07:00

power

mm: remove the implementation of swap_free() and always use swap_free_nr()

2024-07-03 19:30:01 -07:00

printk

printk: Fail pr_flush() if before SYSTEM_SCHEDULING

2024-09-04 15:56:32 +02:00

rcu

rcu: Mark emergency sections in rcu stalls

2024-08-21 15:03:04 +02:00

sched

profiling: remove profile=sleep support

2024-08-04 13:36:28 -07:00

time

timekeeping: Fix bogus clock_was_set() invocation in do_adjtimex()

2024-08-05 16:14:14 +02:00

trace

tracing: Return from tracing_buffers_read() if the file has been closed

2024-08-09 12:59:35 -04:00

.gitignore

…

acct.c

kernel misc: Remove the now superfluous sentinel elements from ctl_table array

2024-04-24 09:43:53 +02:00

async.c

async: Use a dedicated unbound workqueue with raised min_active

2024-02-09 11:13:59 -10:00

audit_fsnotify.c

…

audit_tree.c

fsnotify: create a wrapper fsnotify_find_inode_mark()

2024-04-04 16:24:16 +02:00

audit_watch.c

fsnotify: create a wrapper fsnotify_find_inode_mark()

2024-04-04 16:24:16 +02:00

audit.c

audit: use KMEM_CACHE() instead of kmem_cache_create()

2024-01-25 10:12:22 -05:00

audit.h

…

auditfilter.c

ima: Avoid blocking in RCU read-side critical section

2024-06-13 14:26:50 -04:00

auditsc.c

audit,io_uring: io_uring openat triggers audit reference count underflow

2023-10-13 18:34:46 +02:00

backtracetest.c

backtracetest: add MODULE_DESCRIPTION()

2024-06-24 22:24:55 -07:00

bounds.c

bounds: Use the right number of bits for power-of-two CONFIG_NR_CPUS

2024-04-29 08:29:29 -07:00

capability.c

lsm: constify the 'target' parameter in security_capget()

2023-08-08 16:48:47 -04:00

cfi.c

…

compat.c

…

configs.c

…

context_tracking.c

context_tracking: Make context_tracking_key __ro_after_init

2024-03-22 11:18:18 +01:00

cpu_pm.c

…

cpu.c

cpu/SMT: Enable SMT only if a core is online

2024-08-13 10:31:24 +10:00

crash_core.c

Merge tag 'mm-nonmm-stable-2024-05-19-11-56' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

2024-05-19 14:02:03 -07:00

crash_reserve.c

crash: fix riscv64 crash memory reserve dead loop

2024-08-15 22:16:16 -07:00

cred.c

cred: Use KMEM_CACHE() instead of kmem_cache_create()

2024-02-23 17:33:31 -05:00

delayacct.c

sysctl: treewide: constify the ctl_table argument of proc_handlers

2024-07-24 20:59:29 +02:00

dma.c

…

elfcorehdr.c

crash: remove dependency of FA_DUMP on CRASH_DUMP

2024-02-23 17:48:22 -08:00

exec_domain.c

…

exit.c

Merge tag 'mm-stable-2024-07-21-14-50' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

2024-07-21 17:15:46 -07:00

exit.h

exit: add internal include file with helpers

2023-09-21 12:03:50 -06:00

extable.c

…

fail_function.c

…

fork.c

pidfd: prevent creation of pidfds for kthreads

2024-08-12 22:03:26 +02:00

freezer.c

Merge tag 'v6.7-rc6' into sched/core, to pick up fixes

2023-12-23 15:52:13 +01:00

gen_kheaders.sh

kheaders: use command -v to test for existence of cpio

2024-05-30 01:13:20 +09:00

groups.c

groups: Convert group_info.usage to refcount_t

2023-09-29 11:28:39 -07:00

hung_task.c

sysctl: treewide: constify the ctl_table argument of proc_handlers

2024-07-24 20:59:29 +02:00

iomem.c

kernel/iomem.c: remove __weak ioremap_cache helper

2023-08-21 13:37:28 -07:00

irq_work.c

…

jump_label.c

jump_label: Fix the fix, brown paper bags galore

2024-07-31 12:57:39 +02:00

kallsyms_internal.h

kallsyms: get rid of code for absolute kallsyms

2024-07-20 16:33:21 +09:00

kallsyms_selftest.c

kallsyms: Match symbols exactly with CONFIG_LTO_CLANG

2024-08-15 09:33:35 -07:00

kallsyms_selftest.h

…

kallsyms.c

kallsyms: Match symbols exactly with CONFIG_LTO_CLANG

2024-08-15 09:33:35 -07:00

kcmp.c

file: convert to SLAB_TYPESAFE_BY_RCU

2023-10-19 11:02:48 +02:00

Kconfig.freezer

…

Kconfig.hz

…

Kconfig.kexec

crash: clean up kdump related config items

2024-02-23 17:48:22 -08:00

Kconfig.locks

…

Kconfig.preempt

…

kcov.c

kcov: properly check for softirq context

2024-08-07 18:33:56 -07:00

kexec_core.c

sysctl: treewide: constify the ctl_table argument of proc_handlers

2024-07-24 20:59:29 +02:00

kexec_elf.c

…

kexec_file.c

crash: add a new kexec flag for hotplug support

2024-04-23 14:59:01 +10:00

kexec_internal.h

crash: remove dependency of FA_DUMP on CRASH_DUMP

2024-02-23 17:48:22 -08:00

kexec.c

crash: add a new kexec flag for hotplug support

2024-04-23 14:59:01 +10:00

kheaders.c

…

kprobes.c

kprobes: Fix to check symbol prefixes correctly

2024-08-05 14:04:03 +09:00

ksyms_common.c

…

ksysfs.c

profiling: remove prof_cpu_mask

2024-07-29 10:45:54 -07:00

kthread.c

kunit: Handle test faults

2024-05-06 14:22:02 -06:00

latencytop.c

sysctl: treewide: constify the ctl_table argument of proc_handlers

2024-07-24 20:59:29 +02:00

Makefile

crash: split crash dumping code out from kexec_core.c

2024-02-23 17:48:22 -08:00

module_signature.c

…

notifier.c

…

nsproxy.c

pidfd: add pidfs

2024-03-01 12:23:37 +01:00

numa.c

kernel/numa.c: Move logging out of numa.h

2023-12-20 19:26:30 -05:00

padata.c

padata: Fix possible divide-by-0 panic in padata_mt_helper()

2024-08-07 18:33:56 -07:00

panic.c

panic: Mark emergency section in oops

2024-08-21 15:03:04 +02:00

params.c

params: Fix multi-line comment style

2023-12-01 09:51:44 -08:00

pid_namespace.c

sysctl: treewide: constify the ctl_table argument of proc_handlers

2024-07-24 20:59:29 +02:00

pid_sysctl.h

sysctl: treewide: constify the ctl_table argument of proc_handlers

2024-07-24 20:59:29 +02:00

pid.c

pidfs: remove config option

2024-03-13 12:53:53 -07:00

profile.c

profiling: remove profile=sleep support

2024-08-04 13:36:28 -07:00

ptrace.c

ptrace_attach: shift send(SIGSTOP) into ptrace_set_stopped()

2024-02-22 15:38:52 -08:00

range.c

…

reboot.c

kernel misc: Remove the now superfluous sentinel elements from ctl_table array

2024-04-24 09:43:53 +02:00

regset.c

regset: use kvzalloc() for regset_get_alloc()

2024-04-25 21:07:03 -07:00

relay.c

kernel: relay: remove relay_file_splice_read dead code, doesn't work

2023-12-29 12:22:27 -08:00

resource_kunit.c

resource: add missing MODULE_DESCRIPTION()

2024-06-28 19:36:30 -07:00

resource.c

resource: Export find_resource_space()

2024-05-28 11:14:14 -05:00

rseq.c

…

scftorture.c

scftorture: Make torture_type static

2024-05-30 15:31:51 -07:00

scs.c

…

seccomp.c

sysctl: treewide: constify the ctl_table argument of proc_handlers

2024-07-24 20:59:29 +02:00

signal.c

kernel: rerun task_work while freezing in get_signal()

2024-07-11 01:51:44 -06:00

smp.c

smp: Add missing destroy_work_on_stack() call in smp_call_on_cpu()

2024-07-10 22:40:39 +02:00

smpboot.c

kthread: add kthread_stop_put

2023-10-04 10:41:57 -07:00

smpboot.h

…

softirq.c

softirq: Fix suspicious RCU usage in __do_softirq()

2024-04-29 05:03:51 +02:00

stackleak.c

sysctl: treewide: constify the ctl_table argument of proc_handlers

2024-07-24 20:59:29 +02:00

stacktrace.c

stacktrace: fix kernel-doc typo

2023-12-29 12:22:29 -08:00

static_call_inline.c

…

static_call.c

…

stop_machine.c

…

sys_ni.c

Merge tag 'probes-v6.11' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace

2024-07-18 12:19:20 -07:00

sys.c

Merge tag 'riscv-for-linus-6.10-mw1' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux

2024-05-22 09:56:00 -07:00

sysctl-test.c

sysctl: Add module description to sysctl-testing

2024-06-03 15:20:37 +02:00

sysctl.c

sysctl: treewide: constify the ctl_table argument of proc_handlers

2024-07-24 20:59:29 +02:00

task_work.c

task_work: make TWA_NMI_CURRENT handling conditional on IRQ_WORK

2024-07-29 12:05:06 -07:00

taskstats.c

taskstats: fill_stats_for_tgid: use for_each_thread()

2023-10-04 10:41:57 -07:00

torture.c

torture: Add MODULE_DESCRIPTION()

2024-05-30 15:31:38 -07:00

tracepoint.c

…

tsacct.c

tsacct: replace strncpy() with strscpy()

2024-07-12 16:39:53 -07:00

ucount.c

Merge tag 'sysctl-6.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/sysctl/sysctl

2024-05-17 17:31:24 -07:00

uid16.c

…

uid16.h

…

umh.c

sysctl: treewide: constify the ctl_table argument of proc_handlers

2024-07-24 20:59:29 +02:00

up.c

smp: Change function signatures to use call_single_data_t

2023-09-13 14:59:24 +02:00

user_namespace.c

user_namespace: remove unnecessary NULL values from kbuf

2024-02-22 15:38:52 -08:00

user-return-notifier.c

…

user.c

printk: Change type of CONFIG_BASE_SMALL to bool

2024-05-06 17:39:09 +02:00

usermode_driver.c

…

utsname_sysctl.c

sysctl: treewide: constify the ctl_table argument of proc_handlers

2024-07-24 20:59:29 +02:00

utsname.c

…

vhost_task.c

vhost_task: Handle SIGKILL by flushing work and exiting

2024-05-22 08:31:15 -04:00

vmcore_info.c

kallsyms: get rid of code for absolute kallsyms

2024-07-20 16:33:21 +09:00

watch_queue.c

watch_queue: fix kcalloc() arguments order

2023-12-21 13:17:54 +01:00

watchdog_buddy.c

…

watchdog_perf.c

watchdog/perf: properly initialize the turbo mode timestamp and rearm counter

2024-07-17 21:11:34 -07:00

watchdog.c

sysctl: treewide: constify the ctl_table argument of proc_handlers

2024-07-24 20:59:29 +02:00

workqueue_internal.h

workqueue: Drop the special locking rule for worker->flags and worker_pool->flags

2023-08-07 15:57:22 -10:00

workqueue.c

workqueue: Remove unneeded lockdep_assert_cpus_held()

2024-07-15 14:01:14 -10:00