Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]


Groups > linux.kernel > #1433341

Re: kthread_stop insanity (Re: [[DEBUG] force] 2642458962: BUG: unable to handle kernel paging request at ffffc90000997f18)

From Linus Torvalds <torvalds@linux-foundation.org>
Newsgroups linux.kernel
Subject Re: kthread_stop insanity (Re: [[DEBUG] force] 2642458962: BUG: unable to handle kernel paging request at ffffc90000997f18)
Date 2016-06-28 23:50 +0200
Message-ID <rP93k-3WI-23@gated-at.bofh.it> (permalink)
References (6 earlier) <rP7Ee-3d8-45@gated-at.bofh.it> <rP8gW-3r9-31@gated-at.bofh.it> <rP8Ah-3MT-9@gated-at.bofh.it> <rP8JY-3Qa-9@gated-at.bofh.it> <rP8TD-3Tn-11@gated-at.bofh.it>
Organization linux.* mail to news gateway

Show all headers | View raw


On Tue, Jun 28, 2016 at 2:35 PM, Linus Torvalds
<torvalds@linux-foundation.org> wrote:
> On Tue, Jun 28, 2016 at 2:21 PM, Andy Lutomirski <luto@amacapital.net> wrote:
>
>> If so, that seems considerably more complicated than just adding a reference count.
>
> Fair enough.

Ahh, and if you put the reference count just in the task_struct (next
to the ->stack pointer), then I guess that's particularly trivial.

Then try_get_task_stack(tsk) becomes

     void *try_get_task_stack(struct task_struct *tsk)
     {
          void *stack = tsk->stack;
          if (!atomic_inc_not_zero(&tsk->stackref))
               stack = NULL;
          return stack;
     }

ok, color me convinced.

               Linus

Back to linux.kernel | Previous | NextPrevious in thread | Next in thread | Find similar | Unroll thread


Thread

kthread_stop insanity (Re: [[DEBUG] force] 2642458962: BUG: unable to  handle kernel paging request at ffffc90000997f18) Andy Lutomirski <luto@kernel.org> - 2016-06-27 07:30 +0200
  Re: kthread_stop insanity (Re: [[DEBUG] force] 2642458962: BUG:  unable to handle kernel paging request at ffffc90000997f18) Peter Zijlstra <peterz@infradead.org> - 2016-06-27 10:30 +0200
  Re: kthread_stop insanity (Re: [[DEBUG] force] 2642458962: BUG:  unable to handle kernel paging request at ffffc90000997f18) Oleg Nesterov <oleg@redhat.com> - 2016-06-27 17:00 +0200
    Re: kthread_stop insanity (Re: [[DEBUG] force] 2642458962: BUG:  unable to handle kernel paging request at ffffc90000997f18) Andy Lutomirski <luto@amacapital.net> - 2016-06-27 17:50 +0200
      Re: kthread_stop insanity (Re: [[DEBUG] force] 2642458962: BUG:  unable to handle kernel paging request at ffffc90000997f18) Oleg Nesterov <oleg@redhat.com> - 2016-06-27 19:00 +0200
        Re: kthread_stop insanity (Re: [[DEBUG] force] 2642458962: BUG:  unable to handle kernel paging request at ffffc90000997f18) Oleg Nesterov <oleg@redhat.com> - 2016-06-28 21:00 +0200
          Re: kthread_stop insanity (Re: [[DEBUG] force] 2642458962: BUG:  unable to handle kernel paging request at ffffc90000997f18) Andy Lutomirski <luto@amacapital.net> - 2016-06-28 21:20 +0200
            Re: kthread_stop insanity (Re: [[DEBUG] force] 2642458962: BUG:  unable to handle kernel paging request at ffffc90000997f18) Oleg Nesterov <oleg@redhat.com> - 2016-06-28 22:20 +0200
              Re: kthread_stop insanity (Re: [[DEBUG] force] 2642458962: BUG:  unable to handle kernel paging request at ffffc90000997f18) Andy Lutomirski <luto@amacapital.net> - 2016-06-28 23:00 +0200
                Re: kthread_stop insanity (Re: [[DEBUG] force] 2642458962: BUG:  unable to handle kernel paging request at ffffc90000997f18) Linus Torvalds <torvalds@linux-foundation.org> - 2016-06-28 23:20 +0200
                Re: kthread_stop insanity (Re: [[DEBUG] force] 2642458962: BUG:  unable to handle kernel paging request at ffffc90000997f18) Linus Torvalds <torvalds@linux-foundation.org> - 2016-06-28 23:20 +0200
                Re: kthread_stop insanity (Re: [[DEBUG] force] 2642458962: BUG:  unable to handle kernel paging request at ffffc90000997f18) Andy Lutomirski <luto@amacapital.net> - 2016-06-28 23:30 +0200
                Re: kthread_stop insanity (Re: [[DEBUG] force] 2642458962: BUG:  unable to handle kernel paging request at ffffc90000997f18) Linus Torvalds <torvalds@linux-foundation.org> - 2016-06-28 23:40 +0200
                Re: kthread_stop insanity (Re: [[DEBUG] force] 2642458962: BUG:  unable to handle kernel paging request at ffffc90000997f18) Linus Torvalds <torvalds@linux-foundation.org> - 2016-06-28 23:50 +0200
                Re: kthread_stop insanity (Re: [[DEBUG] force] 2642458962: BUG:  unable to handle kernel paging request at ffffc90000997f18) Oleg Nesterov <oleg@redhat.com> - 2016-06-29 01:00 +0200
                Re: kthread_stop insanity (Re: [[DEBUG] force] 2642458962: BUG:  unable to handle kernel paging request at ffffc90000997f18) Oleg Nesterov <oleg@redhat.com> - 2016-06-29 01:10 +0200
                Re: kthread_stop insanity (Re: [[DEBUG] force] 2642458962: BUG:  unable to handle kernel paging request at ffffc90000997f18) Andy Lutomirski <luto@amacapital.net> - 2016-06-29 17:40 +0200
                [PATCH] kthread: to_live_kthread() needs try_get_task_stack() Oleg Nesterov <oleg@redhat.com> - 2016-06-29 20:10 +0200
                Re: [PATCH] kthread: to_live_kthread() needs try_get_task_stack() kbuild test robot <lkp@intel.com> - 2016-06-29 20:40 +0200
                Re: [PATCH] kthread: to_live_kthread() needs try_get_task_stack() Oleg Nesterov <oleg@redhat.com> - 2016-06-29 20:50 +0200
                Re: [PATCH] kthread: to_live_kthread() needs try_get_task_stack() kbuild test robot <lkp@intel.com> - 2016-06-29 21:00 +0200
                Re: [PATCH] kthread: to_live_kthread() needs try_get_task_stack() Andy Lutomirski <luto@amacapital.net> - 2016-06-30 01:10 +0200
          Re: kthread_stop insanity (Re: [[DEBUG] force] 2642458962: BUG:  unable to handle kernel paging request at ffffc90000997f18) Andy Lutomirski <luto@amacapital.net> - 2016-06-30 01:40 +0200
  Re: kthread_stop insanity (Re: [[DEBUG] force] 2642458962: BUG:  unable to handle kernel paging request at ffffc90000997f18) Linus Torvalds <torvalds@linux-foundation.org> - 2016-06-27 19:20 +0200

csiph-web