Repository files (latest commit first)

Filename	Latest commit message	Latest commit date
Petr Mladek b5fa6d9143 printk: Correctly handle preemption in console_unlock() ... [ Upstream commit 257ab443118bffc7fdcef38f49cf59be68a3e362 ] Some console drivers code calls console_conditional_schedule() that looks at @console_may_schedule. The value must be cleared when the drivers are called from console_unlock() with interrupts disabled. But rescheduling is fine when the same code is called, for example, from tty operations where the console semaphore is taken via console_lock(). This is why @console_may_schedule is cleared before calling console drivers. The original value is stored to decide if we could sleep between lines. Now, @console_may_schedule is not cleared when we call console_trylock() and jump back to the "again" goto label. This has become a problem, since the commit 6b97a20d3a ("printk: set may_schedule for some of console_trylock() callers"). @console_may_schedule might get enabled now. There is also the opposite problem. console_lock() can be called only from preemptive context. It can always enable scheduling in the console code. But console_trylock() is not able to detect it when CONFIG_PREEMPT_COUNT is disabled. Therefore we should use the original @console_may_schedule value after re-acquiring the console semaphore in console_unlock(). This patch solves both problems by moving the "again" goto label. Alternative solution was to clear and restore the value around call_console_drivers(). Then console_conditional_schedule() could be used also inside console_unlock(). But there was a potential race with console_flush_on_panic() as reported by Sergey Senozhatsky. That function should be called only where there is only one CPU and with interrupts disabled. But better be on the safe side because stopping CPUs might fail. Fixes: 6b97a20d3a ("printk: set may_schedule for some of console_trylock() callers") Link: http://lkml.kernel.org/r/1490372045-22288-1-git-send-email-pmladek@suse.com Suggested-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Jiri Slaby <jslaby@suse.cz> Cc: linux-fbdev@vger.kernel.org Cc: linux-kernel@vger.kernel.org Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Signed-off-by: Petr Mladek <pmladek@suse.com> Signed-off-by: Sasha Levin <alexander.levin@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		2018-03-22 09:17:47 +01:00
..
bpf	bpf: add schedule points in percpu arrays management	2018-03-11 16:21:35 +01:00
configs	config: android: enable CONFIG_SECCOMP	2016-10-11 15:06:32 -07:00
debug	kdb: Fix handling of kallsyms_symbol_next() return value	2017-12-14 09:28:13 +01:00
events	perf/x86/intel: Account interrupts for PEBS errors	2017-12-09 22:01:52 +01:00
gcov	gcov: support GCC 7.1	2017-09-02 07:07:53 +02:00
irq	genirq: Guard handle_bad_irq log messages	2018-03-03 10:23:25 +01:00
livepatch	livepatch/module: make TAINT_LIVEPATCH module-specific	2016-08-26 14:42:08 +02:00
locking	rtmutex: Fix PI chain order integrity	2018-03-22 09:17:47 +01:00
power	sched/cpuset/pm: Fix cpuset vs. suspend-resume bugs	2017-10-12 11:51:25 +02:00
printk	printk: Correctly handle preemption in console_unlock()	2018-03-22 09:17:47 +01:00
rcu	rcu: Allow for page faults in NMI handlers	2017-10-18 09:35:38 +02:00
sched	sched/rt: Up the root domain ref count when passing it around via IPIs	2018-02-17 13:21:13 +01:00
time	sysrq: Reset the watchdog timers while displaying high-resolution timers	2018-03-22 09:17:42 +01:00
trace	blktrace: fix unlocked registration of tracepoints	2018-02-25 11:05:41 +01:00
.gitignore
acct.c	kernel/acct.c: fix the acct->needcheck check in check_free_space()	2018-01-10 09:29:51 +01:00
async.c	kernel/async.c: revert "async: simplify lowest_in_progress()"	2018-02-17 13:21:18 +01:00
audit.c	audit: ensure that 'audit=1' actually enables audit for PID 1	2017-12-16 16:25:47 +01:00
audit.h	Merge branch 'stable-4.8' of git://git.infradead.org/users/pcmoore/audit	2016-07-29 17:54:17 -07:00
audit_fsnotify.c
audit_tree.c	audit: cleanup prune_tree_thread	2016-04-04 09:46:47 -04:00
audit_watch.c	audit: Fix use after free in audit_remove_watch_rule()	2017-08-24 17:12:18 -07:00
auditfilter.c	audit: add fields to exclude filter by reusing user filter	2016-06-27 11:01:00 -04:00
auditsc.c	Merge branch 'stable-4.9' of git://git.infradead.org/users/pcmoore/audit	2016-10-04 14:21:41 -07:00
backtracetest.c
bounds.c
capability.c	ptrace: Capture the ptracer's creds not PT_PTRACE_CAP	2017-01-06 10:40:13 +01:00
cgroup.c	cgroup: fix error return value from cgroup_subtree_control()	2017-08-11 08:49:28 -07:00
cgroup_freezer.c
cgroup_pids.c	cgroup/pids: remove spurious suspicious RCU usage warning	2017-03-26 13:05:58 +02:00
compat.c
configs.c
context_tracking.c
cpu.c	timers: Reinitialize per cpu bases on hotplug	2018-01-02 20:35:17 +01:00
cpu_pm.c
cpuset.c	sched/cpuset/pm: Fix cpuset vs. suspend-resume bugs	2017-10-12 11:51:25 +02:00
crash_dump.c
cred.c	cred: Reject inodes with invalid ids in set_create_file_as()	2016-06-30 18:05:09 -05:00
delayacct.c
dma.c
elfcore.c
exec_domain.c
exit.c	sched/autogroup: Do not use autogroup->tg in zombie threads	2016-11-22 12:33:43 +01:00
extable.c	kernel/extable.c: mark core_kernel_text notrace	2017-07-21 07:42:21 +02:00
fork.c	kaiser: stack map PAGE_SIZE at THREAD_SIZE-PAGE_SIZE	2018-01-05 15:46:32 +01:00
freezer.c	freezer, oom: check TIF_MEMDIE on the correct task	2016-07-28 16:07:41 -07:00
futex.c	futex: Prevent overflow by strengthen input validation	2018-01-23 19:57:04 +01:00
futex_compat.c
groups.c	kernel: make groups_sort calling a responsibility group_info allocators	2018-01-10 09:29:52 +01:00
hung_task.c	hung_task: allow hung_task_panic when hung_task_warnings is 0	2016-10-11 15:06:33 -07:00
irq_work.c
jump_label.c	jump_label: Invoke jump_label_test() via early_initcall()	2017-12-14 09:28:24 +01:00
kallsyms.c	kallsyms: add support for relative offsets in kallsyms address table	2016-03-15 16:55:16 -07:00
kcmp.c
Kconfig.freezer
Kconfig.hz
Kconfig.locks
Kconfig.preempt
kcov.c	kcov: detect double association with a single task	2018-02-25 11:05:42 +01:00
kexec.c	kexec: allow architectures to override boot mapping	2016-08-02 19:35:27 -04:00
kexec_core.c	kexec: add restriction on kexec_load() segment sizes	2016-08-02 19:35:31 -04:00
kexec_file.c	kexec: fix double-free when failing to relocate the purgatory	2016-09-01 17:52:01 -07:00
kexec_internal.h
kmod.c
kprobes.c	tracing/kprobes: Enforce kprobes teardown after testing	2017-05-25 15:44:47 +02:00
ksysfs.c	kexec: add a kexec_crash_loaded() function	2016-08-02 19:35:30 -04:00
kthread.c	cgroup, kthread: close race window where new kthreads can be migrated to non-root cgroups	2017-04-21 09:31:18 +02:00
latencytop.c
Makefile	kernel/watchdog.c: move hardlockup detector to separate file	2017-06-17 06:41:57 +02:00
membarrier.c	Fix: Disable sys_membarrier when nohz_full is enabled	2017-03-12 06:41:45 +01:00
memremap.c	mm: Fix devm_memremap_pages() collision handling	2018-02-28 10:18:34 +01:00
module-internal.h
module.c	module/retpoline: Warn about missing retpoline in module	2018-02-13 12:35:58 +01:00
module_signing.c	KEYS: Move the point of trust determination to __key_link()	2016-04-11 22:43:43 +01:00
notifier.c
nsproxy.c
padata.c	padata: free correct variable	2017-05-20 14:28:40 +02:00
panic.c	kernel/panic.c: add missing \n	2017-07-05 14:40:24 +02:00
params.c
pid.c	pids: make task_tgid_nr_ns() safe	2017-08-24 17:12:21 -07:00
pid_namespace.c	pid_ns: Sleep in TASK_INTERRUPTIBLE in zap_pid_ns_processes	2017-05-25 15:44:38 +02:00
profile.c	profile: Convert to hotplug state machine	2016-07-15 10:41:42 +02:00
ptrace.c	ptrace: Properly initialize ptracer_cred on fork	2017-06-14 15:05:54 +02:00
range.c
reboot.c
relay.c	kernel/relay.c: revert "kernel/relay.c: fix potential memory leak"	2018-02-17 13:21:18 +01:00
resource.c	/proc/iomem: only expose physical resource addresses to privileged users	2016-04-14 12:56:09 -07:00
seccomp.c	seccomp: fix the usage of get/put_seccomp_filter() in seccomp_get_filter()	2017-10-05 09:44:02 +02:00
signal.c	kernel/signal.c: remove the no longer needed SIGNAL_UNKILLABLE check in complete_signal()	2018-01-10 09:29:53 +01:00
smp.c	smp: Allocate smp_call_on_cpu() workqueue on stack too	2016-09-22 14:49:10 +02:00
smpboot.c	kthread/smpboot: do not park in kthread_create_on_cpu()	2016-10-11 15:06:33 -07:00
smpboot.h
softirq.c	softirq: Display IRQ_POLL for irq-poll statistics	2016-10-21 15:45:47 -06:00
stacktrace.c	stacktrace, lockdep: Fix address, newline ugliness	2017-02-14 15:25:42 -08:00
stop_machine.c	Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip	2016-10-03 13:39:00 -07:00
sys.c	prctl: make PR_SET_THP_DISABLE wait for mmap_sem killable	2016-05-23 17:04:14 -07:00
sys_ni.c	x86/pkeys: Fix pkeys build breakage for some non-x86 arches	2016-09-13 14:41:36 +02:00
sysctl.c	timer/sysclt: Restrict timer migration sysctl values to 0 and 1	2017-10-05 09:44:04 +02:00
sysctl_binary.c	kernel/sysctl_binary.c: use generic UUID library	2016-05-20 17:58:30 -07:00
task_work.c	task_work: use READ_ONCE/lockless_dereference, avoid pi_lock if !task_works	2016-08-02 19:35:02 -04:00
taskstats.c	taskstats: fix the length of cgroupstats_cmd_get_policy	2016-11-03 16:55:58 -04:00
test_kprobes.c
torture.c	torture: Convert torture_shutdown() to hrtimer	2016-08-22 10:01:49 -07:00
tracepoint.c	kernel/...: convert pr_warning to pr_warn	2016-03-22 15:36:02 -07:00
tsacct.c
ucount.c	kernel/ucount.c: mark user_header with kmemleak_ignore()	2017-06-17 06:41:51 +02:00
uid16.c	kernel: make groups_sort calling a responsibility group_info allocators	2018-01-10 09:29:52 +01:00
up.c	smp: Add function to execute a function synchronously on a CPU	2016-09-05 13:52:39 +02:00
user-return-notifier.c
user.c
user_namespace.c	Merge branch 'nsfs-ioctls' into HEAD	2016-09-22 20:00:36 -05:00
utsname.c	Merge branch 'nsfs-ioctls' into HEAD	2016-09-22 20:00:36 -05:00
utsname_sysctl.c
watchdog.c	kernel/watchdog: prevent false hardlockup on overloaded system	2017-06-17 06:41:57 +02:00
watchdog_hld.c	kernel/watchdog: prevent false hardlockup on overloaded system	2017-06-17 06:41:57 +02:00
workqueue.c	workqueue: Allow retrieval of current task's work struct	2018-03-18 11:18:48 +01:00
workqueue_internal.h	workqueue: Fix NULL pointer dereference	2017-11-15 15:53:17 +01:00