3e4f7a4956
Pull an urgent RCU fix from Paul E. McKenney: "This series contains a pair of commits that permit RCU synchronous grace periods (synchronize_rcu() and friends) to work correctly throughout boot. This eliminates the current "dead time" starting when the scheduler spawns its first taks and ending when the last of RCU's kthreads is spawned (this last happens during early_initcall() time). Although RCU's synchronous grace periods have long been documented as not working during this time, prior to 4.9, the expedited grace periods worked by accident, and some ACPI code came to rely on this unintentional behavior. (Note that this unintentional behavior was -not- reliable. For example, failures from ACPI could occur on !SMP systems and on systems booting with the rcu_normal kernel boot parameter.) Either way, there is a bug that needs fixing, and the 4.9 switch of RCU's expedited grace periods to workqueues could be considered to have caused a regression. This series therefore makes RCU's expedited grace periods operate correctly throughout the boot process. This has been demonstrated to fix the problems ACPI was encountering, and has the added longer-term benefit of simplifying RCU's behavior." Signed-off-by: Ingo Molnar <mingo@kernel.org> |
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| .. | ||
| acpi | ||
| asm-generic | ||
| clocksource | ||
| crypto | ||
| drm | ||
| dt-bindings | ||
| keys | ||
| kvm | ||
| linux | ||
| math-emu | ||
| media | ||
| memory | ||
| misc | ||
| net | ||
| pcmcia | ||
| ras | ||
| rdma | ||
| rxrpc | ||
| scsi | ||
| soc | ||
| sound | ||
| target | ||
| trace | ||
| uapi | ||
| video | ||
| xen | ||
| Kbuild | ||