Re: [PATCH 2/2] perf/hw_breakpoint: Modify breakpoint even if the new attr has disabled set

From: Oleg Nesterov
Date: Mon Aug 06 2018 - 09:49:52 EST


On 08/06, Jiri Olsa wrote:
>
> On Mon, Aug 06, 2018 at 03:07:31PM +0200, Oleg Nesterov wrote:
> > On 08/06, Oleg Nesterov wrote:
> > >
> > > But, with or without this fix, shouldn't we set .disabled = 1 if modify_() fails?
> > > IIUC this doesn't matter, bp->attr.disabled is not really used anyway, but looks a
> > > bit confusing.
> >
> > I am looking at another caller perf_event_modify_breakpoint(). It too doesn't set
> > attr.disabled = 1 on failure, it does _perf_event_enable() instead so attr.disabled
> > should be correct.
> >
> > But this looks wrong. If modify_user_hw_breakpoint_check() paths fails after
> > arch_validate_hwbkpt_settings() was called, then we can not simply restore
>
> hum, arch_validate_hwbkpt_settings was removed recently.. r u checking the last sources?

I do not see this change in Linus's tree...


Nevermind, if this was already changed/fixed somewhere, please forget.

Oleg.