Hello, On 02/19, gregkh@xxxxxxxxxxxxxxxxxxx wrote: > > This is a note to let you know that I've just added the patch titled > > exit: wait_task_zombie: kill the no longer necessary spin_lock_irq(siglock) > > to the 6.1-stable tree which can be found at: > http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary > > The filename of the patch is: > exit-wait_task_zombie-kill-the-no-longer-necessary-spin_lock_irq-siglock.patch > and it can be found in the queue-6.1 subdirectory. > > If you, or anyone else, feels it should not be added to the stable tree, > please let <stable@xxxxxxxxxxxxxxx> know about it. This patch depends on f7ec1cd5cc7e getrusage: use sig->stats_lock rather than lock_task_sighand() 7601df8031fd fs/proc: do_task_stat: use sig->stats_lock to gather the threads/children stats but since FAILED: patch "[PATCH] getrusage: use sig->stats_lock rather than" failed to apply to 6.1-stable tree FAILED: patch "[PATCH] fs/proc: do_task_stat: use sig->stats_lock to gather the" failed to apply to 6.1-stable tree this patch should not be added to 6.1-stable. And in any case this particular patch is not a stable material. Oleg. > From c1be35a16b2f1fe21f4f26f9de030ad6eaaf6a25 Mon Sep 17 00:00:00 2001 > From: Oleg Nesterov <oleg@xxxxxxxxxx> > Date: Tue, 23 Jan 2024 16:34:00 +0100 > Subject: exit: wait_task_zombie: kill the no longer necessary spin_lock_irq(siglock) > > From: Oleg Nesterov <oleg@xxxxxxxxxx> > > commit c1be35a16b2f1fe21f4f26f9de030ad6eaaf6a25 upstream. > > After the recent changes nobody use siglock to read the values protected > by stats_lock, we can kill spin_lock_irq(¤t->sighand->siglock) and > update the comment. > > With this patch only __exit_signal() and thread_group_start_cputime() take > stats_lock under siglock. > > Link: https://lkml.kernel.org/r/20240123153359.GA21866@xxxxxxxxxx > Signed-off-by: Oleg Nesterov <oleg@xxxxxxxxxx> > Signed-off-by: Dylan Hatch <dylanbhatch@xxxxxxxxxx> > Cc: Eric W. Biederman <ebiederm@xxxxxxxxxxxx> > Cc: <stable@xxxxxxxxxxxxxxx> > Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> > Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> > --- > kernel/exit.c | 10 +++------- > 1 file changed, 3 insertions(+), 7 deletions(-) > > --- a/kernel/exit.c > +++ b/kernel/exit.c > @@ -1146,17 +1146,14 @@ static int wait_task_zombie(struct wait_ > * and nobody can change them. > * > * psig->stats_lock also protects us from our sub-threads > - * which can reap other children at the same time. Until > - * we change k_getrusage()-like users to rely on this lock > - * we have to take ->siglock as well. > + * which can reap other children at the same time. > * > * We use thread_group_cputime_adjusted() to get times for > * the thread group, which consolidates times for all threads > * in the group including the group leader. > */ > thread_group_cputime_adjusted(p, &tgutime, &tgstime); > - spin_lock_irq(¤t->sighand->siglock); > - write_seqlock(&psig->stats_lock); > + write_seqlock_irq(&psig->stats_lock); > psig->cutime += tgutime + sig->cutime; > psig->cstime += tgstime + sig->cstime; > psig->cgtime += task_gtime(p) + sig->gtime + sig->cgtime; > @@ -1179,8 +1176,7 @@ static int wait_task_zombie(struct wait_ > psig->cmaxrss = maxrss; > task_io_accounting_add(&psig->ioac, &p->ioac); > task_io_accounting_add(&psig->ioac, &sig->ioac); > - write_sequnlock(&psig->stats_lock); > - spin_unlock_irq(¤t->sighand->siglock); > + write_sequnlock_irq(&psig->stats_lock); > } > > if (wo->wo_rusage) > > > Patches currently in stable-queue which might be from oleg@xxxxxxxxxx are > > queue-6.1/exit-wait_task_zombie-kill-the-no-longer-necessary-spin_lock_irq-siglock.patch > queue-6.1/fs-proc-do_task_stat-move-thread_group_cputime_adjusted-outside-of-lock_task_sighand.patch >
