archives/linux
1
0
Fork 0
mirror of https://github.com/torvalds/linux.git synced 2026-03-08 08:24:47 +01:00
Code Issues Projects Releases Packages Wiki Activity Actions
linux/kernel
History
Anna-Maria Behnsen facd40aa5c timers/migration: Do not rely always on group->parent 
When reading group->parent without holding the group lock it is racy
against CPUs coming online the first time and thereby creating another
level of the hierarchy. This is not a problem when this value is read once
to decide whether to abort a propagation or not. The worst outcome is an
unnecessary/early CPU wake up. But it is racy when reading it several times
during a single 'action' (like activation, deactivation, checking for
remote timer expiry,...) and relying on the consitency of this value
without holding the lock. This happens at the moment e.g. in
tmigr_inactive_up() which is also calling tmigr_udpate_events(). Code relys
on group->parent not to change during this 'action'.

Update parent struct member description to explain the above only
once. Remove parent pointer checks when they are not mandatory (like update
of data->childmask). Remove a warning, which would be nice but the trigger
of this warning is not reliable and add expand the data structure member
description instead. Expand a comment, why it is safe to rely on parent
pointer here (inside hierarchy update).

Fixes: 7ee9887703 ("timers: Implement the hierarchical pull model")
Reported-by: Borislav Petkov <bp@alien8.de>
Signed-off-by: Anna-Maria Behnsen <anna-maria@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lore.kernel.org/r/20240716-tmigr-fixes-v4-1-757baa7803fe@linutronix.de
2024-07-22 18:03:33 +02:00
..
bpf asm-generic fixes for 6.10 2024-06-27 10:53:52 -07:00
cgroup Misc fixes: 2024-05-19 11:38:15 -07:00
configs hardening updates for 6.10-rc1 2024-05-13 14:14:05 -07:00
debug kdb: Simplify management of tmpbuffer in kdb_read() 2024-04-26 17:13:31 +01:00
dma dma-mapping: benchmark: handle NUMA_NO_NODE correctly 2024-05-23 15:06:48 +02:00
entry entry: Respect changes to system call number by trace_sys_enter() 2024-03-12 13:23:32 +01:00
events perf/core: Fix missing wakeup when waiting for context reference 2024-06-05 15:52:33 +02:00
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: Prevent use-after-free in irq_find_at_or_after() 2024-05-24 12:49:35 +02:00
kcsan kcsan, compiler_types: Introduce __data_racy type qualifier 2024-05-07 11:39:50 -07:00
livepatch livepatch: Rename KLP_* to KLP_TRANSITION_* 2024-05-09 15:48:01 +02:00
locking - Core Frameworks 2024-05-22 10:49:54 -07:00
module kallsyms: rework symbol lookup return codes 2024-06-27 17:43:40 +02:00
power vfs-6.10-rc2.fixes 2024-05-27 08:09:12 -07:00
printk Revert "printk: Save console options for add_preferred_console_match()" 2024-06-25 07:58:10 +02:00
rcu Merge branches 'fixes.2024.04.15a', 'misc.2024.04.12a', 'rcu-sync-normal-improve.2024.04.15a', 'rcu-tasks.2024.04.15a' and 'rcutorture.2024.04.15a' into rcu-merge.2024.04.15a 2024-05-01 13:04:02 +02:00
sched bitmap patches for 6.10 2024-05-21 15:29:01 -07:00
time timers/migration: Do not rely always on group->parent 2024-07-22 18:03:33 +02:00
trace kallsyms: rework symbol lookup return codes 2024-06-27 17:43:40 +02:00
.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.c audit: use KMEM_CACHE() instead of kmem_cache_create() 2024-01-25 10:12:22 -05:00
audit.h audit: correct audit_filter_inodes() definition 2023-07-21 12:17:25 -04:00
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
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: Convert from tasklet to BH workqueue 2024-02-05 13:22:34 -10:00
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.c cpu: Fix broken cmdline "nosmp" and "maxcpus=0" 2024-06-23 20:04:14 +02:00
cpu_pm.c
crash_core.c Mainly singleton patches, documented in their respective changelogs. 2024-05-19 14:02:03 -07:00
crash_reserve.c crash: add prefix for crash dumping messages 2024-05-08 08:41:26 -07:00
cred.c cred: Use KMEM_CACHE() instead of kmem_cache_create() 2024-02-23 17:33:31 -05:00
delayacct.c delayacct: Remove the now superfluous sentinel elements from ctl_table array 2024-04-24 09:43:54 +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 virtio: features, fixes, cleanups 2024-05-23 12:04:36 -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 mm: rename mm_put_huge_zero_page to mm_put_huge_zero_folio 2024-04-25 20:56:20 -07:00
freezer.c Linux 6.7-rc6 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 kernel misc: Remove the now superfluous sentinel elements from ctl_table array 2024-04-24 09:43:53 +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,module: Don't alloc static_key_mod for __ro_after_init keys 2024-03-22 11:18:16 +01:00
kallsyms.c kallsyms: rework symbol lookup return codes 2024-06-27 17:43:40 +02:00
kallsyms_internal.h kallsyms: Avoid weak references for kallsyms symbols 2024-05-02 19:48:26 +09:00
kallsyms_selftest.c mm: vmalloc: enable memory allocation profiling 2024-04-25 20:55:57 -07:00
kallsyms_selftest.h
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: don't lose track of remote references during softirqs 2024-06-15 10:43:08 -07:00
kexec.c crash: add a new kexec flag for hotplug support 2024-04-23 14:59:01 +10:00
kexec_core.c kernel misc: Remove the now superfluous sentinel elements from ctl_table array 2024-04-24 09:43:53 +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
kheaders.c
kprobes.c kprobe/ftrace: fix build error due to bad function definition 2024-05-17 19:17:55 -07:00
ksyms_common.c
ksysfs.c vmlinux: Avoid weak reference to notes section 2024-05-02 19:48:26 +09:00
kthread.c kunit: Handle test faults 2024-05-06 14:22:02 -06:00
latencytop.c kernel misc: Remove the now superfluous sentinel elements from ctl_table array 2024-04-24 09:43:53 +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: Disable BH when taking works lock on MT path 2024-04-12 15:07:51 +08:00
panic.c kernel misc: Remove the now superfluous sentinel elements from ctl_table array 2024-04-24 09:43:53 +02:00
params.c params: Fix multi-line comment style 2023-12-01 09:51:44 -08:00
pid.c pidfs: remove config option 2024-03-13 12:53:53 -07:00
pid_namespace.c zap_pid_ns_processes: clear TIF_NOTIFY_SIGNAL along with TIF_SIGPENDING 2024-06-15 10:43:06 -07:00
pid_sysctl.h kernel misc: Remove the now superfluous sentinel elements from ctl_table array 2024-04-24 09:43:53 +02:00
profile.c profiling: Remove create_prof_cpu_mask(). 2024-04-27 11:17:48 -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.c Quite a lot of kexec work this time around. Many singleton patches in 2024-01-09 11:46:20 -08:00
resource_kunit.c
rseq.c
scftorture.c scftorture: Pause testing after memory-allocation failure 2023-07-14 15:02:57 -07:00
scs.c
seccomp.c sysctl changes for v6.10-rc1 2024-05-17 17:31:24 -07:00
signal.c virtio: features, fixes, cleanups 2024-05-23 12:04:36 -07:00
smp.c CSD lock commits for v6.7 2023-10-30 17:56:53 -10:00
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 changes for v6.10-rc1 2024-05-17 17:31:24 -07:00
stacktrace.c stacktrace: fix kernel-doc typo 2023-12-29 12:22:29 -08:00
static_call.c
static_call_inline.c
stop_machine.c
sys.c RISC-V Patches for the 6.10 Merge Window, Part 1 2024-05-22 09:56:00 -07:00
sys_ni.c syscalls: fix compat_sys_io_pgetevents_time64 usage 2024-06-25 15:57:20 +02:00
sysctl-test.c
sysctl.c kernel misc: Remove the now superfluous sentinel elements from ctl_table array 2024-04-24 09:43:53 +02:00
task_work.c task_work: add kerneldoc annotation for 'data' argument 2023-09-19 13:21:32 -07:00
taskstats.c taskstats: fill_stats_for_tgid: use for_each_thread() 2023-10-04 10:41:57 -07:00
torture.c torture: Print out torture module parameters 2023-09-24 17:24:01 +02:00
tracepoint.c
tsacct.c
ucount.c sysctl changes for v6.10-rc1 2024-05-17 17:31:24 -07:00
uid16.c
uid16.h
umh.c umh: Remove the now superfluous sentinel elements from ctl_table array 2024-04-24 09:43:53 +02:00
up.c smp: Change function signatures to use call_single_data_t 2023-09-13 14:59:24 +02:00
user-return-notifier.c
user.c printk: Change type of CONFIG_BASE_SMALL to bool 2024-05-06 17:39:09 +02:00
user_namespace.c user_namespace: remove unnecessary NULL values from kbuf 2024-02-22 15:38:52 -08:00
usermode_driver.c
utsname.c
utsname_sysctl.c kernel misc: Remove the now superfluous sentinel elements from ctl_table array 2024-04-24 09:43:53 +02:00
vhost_task.c vhost_task: Handle SIGKILL by flushing work and exiting 2024-05-22 08:31:15 -04:00
vmcore_info.c mm: free up PG_slab 2024-04-25 20:56:00 -07:00
watch_queue.c watch_queue: fix kcalloc() arguments order 2023-12-21 13:17:54 +01:00
watchdog.c Mainly singleton patches, documented in their respective changelogs. 2024-05-19 14:02:03 -07:00
watchdog_buddy.c watchdog/hardlockup: move SMP barriers from common code to buddy code 2023-06-19 16:25:28 -07:00
watchdog_perf.c kernel/watchdog_perf.c: tidy up kerneldoc 2024-05-08 08:41:29 -07:00
workqueue.c workqueue: Refactor worker ID formatting and make wq_worker_comm() use full ID string 2024-05-20 13:28:40 -10:00
workqueue_internal.h workqueue: Drop the special locking rule for worker->flags and worker_pool->flags 2023-08-07 15:57:22 -10:00