[lkml]   [2021]   [Feb]   [23]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
SubjectRe: [PATCH v4 bpf-next 2/6] bpf: prevent deadlock from recursive bpf_task_storage_[get|delete]
On Mon, Feb 22, 2021 at 05:20:10PM -0800, Song Liu wrote:
> BPF helpers bpf_task_storage_[get|delete] could hold two locks:
> bpf_local_storage_map_bucket->lock and bpf_local_storage->lock. Calling
> these helpers from fentry/fexit programs on functions in bpf_*_storage.c
> may cause deadlock on either locks.
> Prevent such deadlock with a per cpu counter, bpf_task_storage_busy, which
> is similar to bpf_prog_active. We need this counter to be global, because

So bpf_prog_active is one of the biggest turds around, and now you're
making it worse ?!

 \ /
  Last update: 2021-02-23 12:09    [W:0.106 / U:14.356 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site