From: Oleg Nesterov <oleg@xxxxxxxxxx> [ Upstream commit 7904e53ed5a20fc678c01d5d1b07ec486425bb6a ] do/while_each_thread should be avoided when possible. Link: https://lkml.kernel.org/r/20230909164501.GA11581@xxxxxxxxxx Signed-off-by: Oleg Nesterov <oleg@xxxxxxxxxx> Cc: Eric W. Biederman <ebiederm@xxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> Stable-dep-of: 7601df8031fd ("fs/proc: do_task_stat: use sig->stats_lock to gather the threads/children stats") [mheyne: adjusted context] Signed-off-by: Maximilian Heyne <mheyne@xxxxxxxxx> --- Compile-tested only. We're seeing soft lock-ups with 5.10.237 because of the backport of commit 4fe85bdaabd6 ("fs/proc: do_task_stat: use sig->stats_lock to gather the threads/children stats"). I'm assuming this is broken on 5.15 too. --- fs/proc/array.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/fs/proc/array.c b/fs/proc/array.c index 2cb01aaa67187..2ff568dc58387 100644 --- a/fs/proc/array.c +++ b/fs/proc/array.c @@ -530,18 +530,18 @@ static int do_task_stat(struct seq_file *m, struct pid_namespace *ns, cgtime = sig->cgtime; if (whole) { - struct task_struct *t = task; + struct task_struct *t; min_flt = sig->min_flt; maj_flt = sig->maj_flt; gtime = sig->gtime; rcu_read_lock(); - do { + __for_each_thread(sig, t) { min_flt += t->min_flt; maj_flt += t->maj_flt; gtime += task_gtime(t); - } while_each_thread(task, t); + } rcu_read_unlock(); } } while (need_seqretry(&sig->stats_lock, seq)); -- 2.47.1 Amazon Web Services Development Center Germany GmbH Tamara-Danz-Str. 13 10243 Berlin Geschaeftsfuehrung: Christian Schlaeger, Jonathan Weiss Eingetragen am Amtsgericht Charlottenburg unter HRB 257764 B Sitz: Berlin Ust-ID: DE 365 538 597