linux/kernel
Sven Schnelle c57824d4fe workqueue: Fix selection of wake_cpu in kick_pool()
commit 57a01eafdc upstream.

With cpu_possible_mask=0-63 and cpu_online_mask=0-7 the following
kernel oops was observed:

smp: Bringing up secondary CPUs ...
smp: Brought up 1 node, 8 CPUs
Unable to handle kernel pointer dereference in virtual kernel address space
Failing address: 0000000000000000 TEID: 0000000000000803
[..]
 Call Trace:
arch_vcpu_is_preempted+0x12/0x80
select_idle_sibling+0x42/0x560
select_task_rq_fair+0x29a/0x3b0
try_to_wake_up+0x38e/0x6e0
kick_pool+0xa4/0x198
__queue_work.part.0+0x2bc/0x3a8
call_timer_fn+0x36/0x160
__run_timers+0x1e2/0x328
__run_timer_base+0x5a/0x88
run_timer_softirq+0x40/0x78
__do_softirq+0x118/0x388
irq_exit_rcu+0xc0/0xd8
do_ext_irq+0xae/0x168
ext_int_handler+0xbe/0xf0
psw_idle_exit+0x0/0xc
default_idle_call+0x3c/0x110
do_idle+0xd4/0x158
cpu_startup_entry+0x40/0x48
rest_init+0xc6/0xc8
start_kernel+0x3c4/0x5e0
startup_continue+0x3c/0x50

The crash is caused by calling arch_vcpu_is_preempted() for an offline
CPU. To avoid this, select the cpu with cpumask_any_and_distribute()
to mask __pod_cpumask with cpu_online_mask. In case no cpu is left in
the pool, skip the assignment.

tj: This doesn't fully fix the bug as CPUs can still go down between picking
the target CPU and the wake call. Fixing that likely requires adding
cpu_online() test to either the sched or s390 arch code. However, regardless
of how that is fixed, workqueue shouldn't be picking a CPU which isn't
online as that would result in unpredictable and worse behavior.

Signed-off-by: Sven Schnelle <svens@linux.ibm.com>
Fixes: 8639ecebc9 ("workqueue: Implement non-strict affinity scope for unbound workqueues")
Cc: stable@vger.kernel.org # v6.6+
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-05-17 12:02:31 +02:00
..
bpf bpf: Check bloom filter map value size 2024-05-17 12:02:11 +02:00
cgroup cgroup/cpuset: Fix retval in update_cpumask() 2024-04-03 15:28:40 +02:00
configs Kbuild updates for v6.6 2023-09-05 11:01:47 -07:00
debug kdb: Fix a potential buffer overflow in kdb_local() 2024-01-25 15:36:00 -08:00
dma swiotlb: initialise restricted pool list_head when SWIOTLB_DYNAMIC=y 2024-05-17 12:02:08 +02:00
entry entry: Respect changes to system call number by trace_sys_enter() 2024-04-03 15:28:50 +02:00
events perf: Fix the nr_addr_filters fix 2024-02-05 20:14:33 +00:00
futex futex: Don't include process MM in futex key on no-MMU 2023-11-20 11:58:53 +01:00
gcov gcov: shut up missing prototype warnings for internal stubs 2023-08-18 10:18:58 -07:00
irq genirq: Initialize resend_node hlist for all interrupt descriptors 2024-01-31 16:19:13 -08:00
kcsan kcsan: Don't expect 64 bits atomic builtins from 32 bits architectures 2023-06-09 23:29:50 +10:00
livepatch livepatch: Fix missing newline character in klp_resolve_symbols() 2023-11-20 11:59:25 +01:00
locking lockdep: Fix block chain corruption 2023-12-03 07:33:06 +01:00
module modules: wait do_free_init correctly 2024-03-26 18:19:55 -04:00
power PM: s2idle: Make sure CPUs will wakeup directly on resume 2024-04-17 11:19:26 +02:00
printk printk: For @suppress_panic_printk check for other CPU in panic 2024-04-13 13:07:29 +02:00
rcu rcu/nocb: Fix WARN_ON_ONCE() in the rcu_nocb_bypass_lock() 2024-04-13 13:07:34 +02:00
sched sched/eevdf: Prevent vlag from going out of bounds in reweight_eevdf() 2024-05-02 16:32:49 +02:00
time timekeeping: Fix cross-timestamp interpolation for non-x86 2024-03-26 18:19:19 -04:00
trace tracing: hide unused ftrace_event_id_fops 2024-04-17 11:19:33 +02:00
.gitignore
acct.c audit/stable-6.6 PR 20230829 2023-08-30 08:17:35 -07:00
async.c async: Introduce async_schedule_dev_nocall() 2024-01-31 16:18:49 -08:00
audit_fsnotify.c
audit_tree.c
audit_watch.c audit: don't WARN_ON_ONCE(!current->mm) in audit_exe_compare() 2023-11-28 17:19:56 +00:00
audit.c audit: Send netlink ACK before setting connection in auditd_set 2024-02-05 20:14:14 +00:00
audit.h audit: correct audit_filter_inodes() definition 2023-07-21 12:17:25 -04:00
auditfilter.c audit: move trailing statements to next line 2023-08-15 18:16:14 -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
bounds.c bounds: Use the right number of bits for power-of-two CONFIG_NR_CPUS 2024-05-02 16:32:50 +02:00
capability.c lsm: constify the 'target' parameter in security_capget() 2023-08-08 16:48:47 -04:00
cfi.c
compat.c sched_getaffinity: don't assume 'cpumask_size()' is fully initialized 2023-03-14 19:32:38 -07:00
configs.c
context_tracking.c locking/atomic: treewide: use raw_atomic*_<op>() 2023-06-05 09:57:20 +02:00
cpu_pm.c cpuidle, cpu_pm: Remove RCU fiddling from cpu_pm_{enter,exit}() 2023-01-13 11:48:15 +01:00
cpu.c cpu: Re-enable CPU mitigations by default for !X86 architectures 2024-05-02 16:32:44 +02:00
crash_core.c mm: turn folio_test_hugetlb into a PageType 2024-05-02 16:32:47 +02:00
crash_dump.c
cred.c cred: get rid of CONFIG_DEBUG_CREDENTIALS 2023-12-20 17:01:51 +01:00
delayacct.c delayacct: track delays from IRQ/SOFTIRQ 2023-04-18 16:39:34 -07:00
dma.c
exec_domain.c
exit.c cred: get rid of CONFIG_DEBUG_CREDENTIALS 2023-12-20 17:01:51 +01:00
extable.c
fail_function.c kernel/fail_function: fix memory leak with using debugfs_lookup() 2023-02-08 13:36:22 +01:00
fork.c fork: defer linking file vma until vma is fully initialized 2024-05-02 16:32:42 +02:00
freezer.c
gen_kheaders.sh Revert "kheaders: substituting --sort in archive creation" 2023-05-28 16:20:21 +09:00
groups.c
hung_task.c kernel/hung_task.c: set some hung_task.c variables storage-class-specifier to static 2023-04-08 13:45:37 -07:00
iomem.c kernel/iomem.c: remove __weak ioremap_cache helper 2023-08-21 13:37:28 -07:00
irq_work.c trace: Add trace_ipi_send_cpu() 2023-03-24 11:01:29 +01:00
jump_label.c jump_label: Prevent key->enabled int overflow 2022-12-01 15:53:05 -08:00
kallsyms_internal.h
kallsyms_selftest.c Modules changes for v6.6-rc1 2023-08-29 17:32:32 -07:00
kallsyms_selftest.h
kallsyms.c kallsyms: Change func signature for cleanup_symbol_name() 2023-08-25 15:00:36 -07:00
kcmp.c
Kconfig.freezer
Kconfig.hz
Kconfig.kexec kexec: select CRYPTO from KEXEC_FILE instead of depending on it 2024-01-05 15:19:41 +01:00
Kconfig.locks
Kconfig.preempt
kcov.c kcov: add prototypes for helper functions 2023-06-09 17:44:17 -07:00
kexec_core.c kexec: do syscore_shutdown() in kernel_kexec 2024-01-31 16:18:56 -08:00
kexec_elf.c
kexec_file.c integrity-v6.6 2023-08-30 09:16:56 -07:00
kexec_internal.h
kexec.c kernel: kexec: copy user-array safely 2023-11-28 17:19:40 +00:00
kheaders.c kheaders: Use array declaration instead of char 2023-03-24 20:10:59 -07:00
kprobes.c kprobes: Fix possible use-after-free issue on kprobe registration 2024-04-17 11:19:34 +02:00
ksyms_common.c kallsyms: make kallsyms_show_value() as generic function 2023-06-08 12:27:20 -07:00
ksysfs.c crash: hotplug support for kexec_load() 2023-08-24 16:25:14 -07:00
kthread.c kthread: unexport __kthread_should_park() 2023-08-18 10:18:59 -07:00
latencytop.c
Makefile v6.5-rc1-modules-next 2023-06-28 15:51:08 -07:00
module_signature.c
notifier.c notifiers: add tracepoints to the notifiers infrastructure 2023-04-08 13:45:38 -07:00
nsproxy.c nsproxy: Convert nsproxy.count to refcount_t 2023-08-21 11:29:12 -07:00
padata.c crypto: pcrypt - Fix hungtask for PADATA_RESET 2023-11-28 17:19:42 +00:00
panic.c panic: Flush kernel log buffer at the end 2024-04-13 13:07:29 +02:00
params.c kernel: params: Remove unnecessary ‘0’ values from err 2023-07-10 12:47:01 -07:00
pid_namespace.c memfd: replace ratcheting feature from vm.memfd_noexec with hierarchy 2023-08-21 13:37:59 -07:00
pid_sysctl.h memfd: replace ratcheting feature from vm.memfd_noexec with hierarchy 2023-08-21 13:37:59 -07:00
pid.c pidfd: prevent a kernel-doc warning 2023-09-19 13:21:33 -07:00
profile.c
ptrace.c ptrace: Provide set/get interface for syscall user dispatch 2023-04-16 14:23:07 +02:00
range.c
reboot.c kernel/reboot: emergency_restart: Set correct system_state 2023-11-28 17:20:04 +00:00
regset.c
relay.c kernel: relay: remove unnecessary NULL values from relay_open_buf 2023-08-18 10:18:55 -07:00
resource_kunit.c
resource.c kernel/resource: Increment by align value in get_free_mem_region() 2024-01-10 17:16:58 +01:00
rseq.c rseq: Extend struct rseq with per-memory-map concurrency ID 2022-12-27 12:52:12 +01:00
scftorture.c scftorture: Pause testing after memory-allocation failure 2023-07-14 15:02:57 -07:00
scs.c
seccomp.c seccomp: Add missing kerndoc notations 2023-08-17 12:32:15 -07:00
signal.c signal: print comm and exe name on fatal signals 2023-08-18 10:18:50 -07:00
smp.c smp,csd: Throw an error if a CSD lock is stuck for too long 2023-11-28 17:19:36 +00:00
smpboot.c cpu/hotplug: Remove unused state functions 2023-05-15 13:45:00 +02:00
smpboot.h
softirq.c sched/core: introduce sched_core_idle_cpu() 2023-07-13 15:21:50 +02:00
stackleak.c stackleak: allow to specify arch specific stackleak poison function 2023-04-20 11:36:35 +02:00
stacktrace.c
static_call_inline.c
static_call.c
stop_machine.c
sys_ni.c posix-timers: Get rid of [COMPAT_]SYS_NI() uses 2024-01-20 11:51:46 +01:00
sys.c prctl: generalize PR_SET_MDWE support check to be per-arch 2024-04-03 15:28:54 +02:00
sysctl-test.c
sysctl.c v6.5-rc1-sysctl-next 2023-06-28 16:05:21 -07:00
task_work.c task_work: add kerneldoc annotation for 'data' argument 2023-09-19 13:21:32 -07:00
taskstats.c
torture.c rcutorture: Fix stuttering races and other issues 2023-11-28 17:20:08 +00:00
tracepoint.c tracepoint: Allow livepatch module add trace event 2023-02-18 14:34:36 -05:00
tsacct.c
ucount.c sysctl: Add size to register_sysctl 2023-08-15 15:26:17 -07:00
uid16.c
uid16.h
umh.c sysctl: fix unused proc_cap_handler() function warning 2023-06-29 15:19:43 -07:00
up.c
user_namespace.c userns: fix a struct's kernel-doc notation 2023-02-02 22:50:04 -08:00
user-return-notifier.c
user.c kernel/user: Allow user_struct::locked_vm to be usable for iommufd 2022-11-30 20:16:49 -04:00
usermode_driver.c
utsname_sysctl.c utsname: simplify one-level sysctl registration for uts_kern_table 2023-04-13 11:49:35 -07:00
utsname.c
vhost_task.c vhost: Fix worker hangs due to missed wake up calls 2023-06-08 15:43:09 -04:00
watch_queue.c kernel: watch_queue: copy user-array safely 2023-11-28 17:19:40 +00:00
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 watchdog/perf: add a weak function for an arch to detect if perf can use NMIs 2023-06-09 17:44:21 -07:00
watchdog.c watchdog: move softlockup_panic back to early_param 2023-11-28 17:19:57 +00:00
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: Fix selection of wake_cpu in kick_pool() 2024-05-17 12:02:31 +02:00