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

Groups > linux.kernel > #1728424

Re: [PATCH] mm/debug: Change BUG_ON() crashes to survivable WARN_ON() warnings

Show all headers | View raw

On Thu, Sep 7, 2017 at 12:01 AM, Ingo Molnar <mingo@kernel.org> wrote:
>
> On a related note, this bug could have been more debuggable I think.
> Could we _please_ change VM_BUG_ON() to WARN_ON() or such?

I think it should be WARN_ON_ONCE(), or at least rate-limited some way.

Because once you have one of the VM bugs, they tend to repeat.

(We had a discussion long ago about making the "ONCE" behavior
actually be "once in a blue moon", and just mean that you warn at most
once every five minutes or something like that. Because the "once"
behavior has also resulted in people missing bugs, because the machine
has been up a long time, and maybe you got a warning at boot time, but
then five days later something fails silently again).

Also, should you do a "dump_vma()" if you then don't give a call stack
because you already did it earlier? So the rate limiting would need to
cover that part too, methinks.

                  Linus

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

Thread

[PATCH 1/2] x86/mm: Reinitialize TLB state on hotplug and resume Andy Lutomirski <luto@kernel.org> - 2017-09-07 05:00 +0200
  [PATCH] mm/debug: Change BUG_ON() crashes to survivable WARN_ON()  warnings Ingo Molnar <mingo@kernel.org> - 2017-09-07 09:10 +0200
    Re: [PATCH] mm/debug: Change BUG_ON() crashes to survivable WARN_ON() warnings Linus Torvalds <torvalds@linux-foundation.org> - 2017-09-07 23:00 +0200
  Re: [PATCH 1/2] x86/mm: Reinitialize TLB state on hotplug and  resume Jiri Kosina <jikos@kernel.org> - 2017-09-07 09:40 +0200
    Re: [PATCH 1/2] x86/mm: Reinitialize TLB state on hotplug and resume Ingo Molnar <mingo@kernel.org> - 2017-09-07 09:50 +0200
      Re: [PATCH 1/2] x86/mm: Reinitialize TLB state on hotplug and  resume Jiri Kosina <jikos@kernel.org> - 2017-09-07 22:00 +0200
        Re: [PATCH 1/2] x86/mm: Reinitialize TLB state on hotplug and resume Andy Lutomirski <luto@amacapital.net> - 2017-09-08 03:30 +0200
  Re: [PATCH 1/2] x86/mm: Reinitialize TLB state on hotplug and resume Ingo Molnar <mingo@kernel.org> - 2017-09-07 12:00 +0200
    Re: [PATCH 1/2] x86/mm: Reinitialize TLB state on hotplug and resume Borislav Petkov <bp@suse.de> - 2017-09-07 12:20 +0200
  Re: [PATCH 1/2] x86/mm: Reinitialize TLB state on hotplug and resume Borislav Petkov <bp@suse.de> - 2017-09-07 12:00 +0200

csiph-web