Panic: Bad link elm 0x... next->prev != elm

["Magliano Andre\'" <masterblaster@xxxxxxxxxx>]

Hi all,

i'm running v2.11.0.397.g4b06a0-DEVELOPMENT x86_64

I got this kind of panic on a daily basis, always at night (probably
while hammer does reblocking?):

Jun 20 03:09:14 randy kernel: ahci0.1: disk_rw: unknown state 6
Jun 20 03:09:14 randy last message repeated 18 times
Jun 20 03:09:14 randy kernel: panic: Bad link elm 0xffffffe01e019e78
next->prev != elm
Jun 20 03:09:14 randy kernel: cpuid = 0
Jun 20 03:09:14 randy kernel: Trace beginning at frame 0xffffffe01de1fa00
Jun 20 03:09:14 randy kernel: panic() at panic+0x1ed
Jun 20 03:09:14 randy kernel: panic() at panic+0x1ed
Jun 20 03:09:14 randy kernel: camisr_runqueue() at camisr_runqueue+0x87
Jun 20 03:09:14 randy kernel: swi_cambio() at swi_cambio+0x169
Jun 20 03:09:14 randy kernel: ithread_handler() at ithread_handler+0x1ba
Jun 20 03:09:14 randy kernel: boot() called on cpu#0

After applying these two patches it's running stable since 4 days.

The difference is now that TAILQ_EMPTY (patch 0002) is in
camisr_runqueue() *and* is protected by a spinlock too. The last maybe
fixes the panic? Does it makes sense?

ByE!

Attachment: 0001-Optimize-isr-routine-from-FreeBSD-proved-to-work.patch
Description: Binary data

Attachment: 0002-TAILQ_EMPTY-now-done-in-camisr_runqueue-so-useless-h.patch
Description: Binary data