[v2,0/9] A few more cpuidle vs rcu fixes

Message

Peter Zijlstra Jan. 26, 2023, 3:08 p.m. UTC

0-day robot reported graph-tracing made the cpuidle-vs-rcu rework go splat.

These patches appear to cure this, the ftrace selftest now runs to completion
without spamming scary messages to dmesg.

Since v1:

 - fixed recursive RCU splats
 - fixed psci thingies for arm (null)
 - improved the tracing WARN (rostedt)
 - fixed TRACE_PREEMPT_TOGGLE (null)

---
 arch/x86/include/asm/atomic64_32.h | 44 +++++++++++++++++++-------------------
 arch/x86/include/asm/atomic64_64.h | 36 +++++++++++++++----------------
 arch/x86/include/asm/kvmclock.h    |  2 +-
 arch/x86/include/asm/paravirt.h    |  2 +-
 arch/x86/include/asm/pvclock.h     |  3 ++-
 arch/x86/kernel/cpu/vmware.c       |  2 +-
 arch/x86/kernel/kvmclock.c         |  6 +++---
 arch/x86/kernel/pvclock.c          | 22 +++++++++++++------
 arch/x86/kernel/tsc.c              |  7 +++---
 arch/x86/xen/time.c                | 12 +++++++++--
 drivers/cpuidle/cpuidle.c          |  2 +-
 drivers/cpuidle/poll_state.c       |  2 --
 drivers/firmware/psci/psci.c       | 31 ++++++++++++++++-----------
 include/linux/context_tracking.h   | 27 +++++++++++++++++++++++
 include/linux/math64.h             |  4 ++--
 include/linux/sched/clock.h        |  8 +++----
 include/linux/trace_recursion.h    | 18 ++++++++++++++++
 kernel/locking/lockdep.c           |  3 +++
 kernel/panic.c                     |  5 +++++
 kernel/sched/clock.c               | 27 +++++++++++++++++------
 kernel/trace/trace_preemptirq.c    |  6 ++----
 lib/bug.c                          | 15 ++++++++++++-
 22 files changed, 192 insertions(+), 92 deletions(-)

Comments

Paul E. McKenney Jan. 29, 2023, 11:23 p.m. UTC | #1

On Thu, Jan 26, 2023 at 04:08:29PM +0100, Peter Zijlstra wrote:
> 0-day robot reported graph-tracing made the cpuidle-vs-rcu rework go splat.
> 
> These patches appear to cure this, the ftrace selftest now runs to completion
> without spamming scary messages to dmesg.
> 
> Since v1:
> 
>  - fixed recursive RCU splats
>  - fixed psci thingies for arm (null)
>  - improved the tracing WARN (rostedt)
>  - fixed TRACE_PREEMPT_TOGGLE (null)
> 
> ---

Applying this gets me the name objtool warnings noted before, but only
on KASAN kernels.  Other than that, works fine as far as rcutorture
is concerned.

							Thanx, Paul