On Fri, 16 Aug 2019 15:04:44 +0000, Vlad Buslov wrote: > >> [ 401.511871] RSP: 002b:00007ffca2a9fad8 EFLAGS: 00000246 ORIG_RAX: > >> 0000000000000001 > >> [ 401.511875] RAX: ffffffffffffffda RBX: 0000000000000002 RCX: > >> 00007fad892d30f8 > >> [ 401.511878] RDX: 0000000000000002 RSI: 000055afeb072a90 RDI: > >> 0000000000000001 > >> [ 401.511881] RBP: 000055afeb072a90 R08: 00000000ffffffff R09: > >> 000000000000000a > >> [ 401.511884] R10: 000055afeb058710 R11: 0000000000000246 R12: > >> 0000000000000002 > >> [ 401.511887] R13: 00007fad893a8780 R14: 0000000000000002 R15: > >> 00007fad893a3740 > >> > >> I don't think it is correct approach to try to call these callbacks with > >> rcu protection because: > >> > >> - Cls API uses sleeping locks that cannot be used in rcu read section > >> (hence the included trace). > >> > >> - It assumes that all implementation of classifier ops reoffload() don't > >> sleep. > >> > >> - And that all driver offload callbacks (both block and classifier > >> setup) don't sleep, which is not the case. > >> > >> I don't see any straightforward way to fix this, besides using some > >> other locking mechanism to protect block_ing_cb_list. > >> > >> Regards, > >> Vlad > > > > Maybe get the mutex flow_indr_block_ing_cb_lock for both lookup, add, > > delete? > > > > the callbacks_lists. the add and delete is work only on modules init case. > > So the > > > > lookup is also not frequently(ony [un]register) and can protect with the > > locks. > > That should do the job. I'll send the patch.
Hi Vlad! While looking into this, would you mind also add the missing flow_block_cb_is_busy() calls in the indirect handlers in the drivers? LMK if you're too busy, I don't want this to get forgotten :)
