On Mon, Jun 17, 2024 at 10:35:10PM +0200, Thomas Gleixner wrote: > > From: Oleg Nesterov <oleg@xxxxxxxxxx> > > commit 07c54cc5988f19c9642fd463c2dbdac7fc52f777 upstream. > > After the recent commit 5097cbcb38e6 ("sched/isolation: Prevent boot crash > when the boot CPU is nohz_full") the kernel no longer crashes, but there is > another problem. > > In this case tick_setup_device() calls tick_take_do_timer_from_boot() to > update tick_do_timer_cpu and this triggers the WARN_ON_ONCE(irqs_disabled) > in smp_call_function_single(). > > Kill tick_take_do_timer_from_boot() and just use WRITE_ONCE(), the new > comment explains why this is safe (thanks Thomas!). > > Fixes: 08ae95f4fd3b ("nohz_full: Allow the boot CPU to be nohz_full") > Signed-off-by: Oleg Nesterov <oleg@xxxxxxxxxx> > Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx> > Cc: stable@xxxxxxxxxxxxxxx > Link: https://lore.kernel.org/r/20240528122019.GA28794@xxxxxxxxxx > Link: https://lore.kernel.org/all/20240522151742.GA10400@xxxxxxxxxx > --- > Backport to v6.6.y and earlier Now queued up, thanks. greg k-h