Messages in this thread | | | Date | Tue, 04 Mar 2014 20:43:38 -0000 | From | Thomas Gleixner <> | Subject | [patch 0/5] genirq: Sanitize irq_set_affinity callbacks |
| |
In my last tree wide sweep of irq controller related oddities I discovered that some controllers have an broken implementation versus selecting a single target cpu from the given cpu mask.
The core merily guarantees that at least one of the cpus in the mask is online.
If the controller callback does not restrict the search for a single target to the online cpus it might run into the following situation:
Assume 4 cores online: online mask = 0x0f
Offline Core 1 online mask = 0x0d
Set affinity to 0xe is valid due to online mask 0xd
cpumask_first(0xe) picks core 1, which is offline
The following series takes care of this. The patches should be tagged stable if there are no objections.
I'm pondering to extend the core functionality to select a target cpu before calling into irq_set_affinity() to prevent future copy and paste failures and get rid of all the duplicated code.
Thanks,
tglx
| |