On Wed, 31 Oct 2018, Daniel Wagner wrote:
Backporting all qspinlock related patches is very likely to introduce regressions on v4.4. Therefore, the recommended solution by Peter and Thomas is to drop back to ticket spinlocks for v4.4.
Link :https://lkml.kernel.org/r/20180921120226.6xjgr4oiho22ex75@linutronix.de Link: https://lkml.kernel.org/r/20180926110117.405325143@infradead.org Cc: Sebastian Andrzej Siewior bigeasy@linutronix.de Cc: Peter Zijlstra peterz@infradead.org Cc: Thomas Gleixner tglx@linutronix.de
Acked-by: Thomas Gleixner tglx@linutronix.de
Signed-off-by: Daniel Wagner daniel.wagner@siemens.com
Thomas suggest following plan for fixing the issues on the varous stable trees:
4.4: Trivial by switching back to ticket locks.
4.9: Decide whether bringing back ticket locks or backporting all qrlock fixes. Sebastian has done the latter already and it's probably the right solution
4.14: 4.18: Backporting the qrlock fixes
4.19: Either the fix ends up in 4.19 final or it needs to be backported
Looks about right. Sebastian, can you please provide the 4.9 backport as a patch series?
Thanks,
tglx