From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Ananyev, Konstantin" <konstantin.ananyev@intel.com>
Subject: Re: [PATCH V20 2/4] eal: add failure handler mechanism
	for hot plug
Date: Fri, 20 Apr 2018 16:16:23 +0000
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> > +
> > +static void sigbus_handler(int signum __rte_unused, siginfo_t *info,
> > +				void *ctx __rte_unused)
> > +{
> > +	int ret;
> > +
> > +	RTE_LOG(ERR, EAL, "SIGBUS error, fault address:%p\n", info->si_addr);
> > +	ret =3D dev_uev_failure_process(NULL, info->si_addr);
>=20
> As now you can try to mmap/munmap same address from two or more different=
 threads
> you probably need some synchronization here.
> Something simple as spinlock seems to be enough here.
> We might have one per device or might be even a global one would be ok he=
re.
>=20
> > +	if (!ret)
> > +		RTE_LOG(DEBUG, EAL,
> > +			"SIGBUS error is because of hot unplug!\n");

Also if sigbus handler wasn't able to fix things - failure addr doesn't bel=
ong to=20
any devices, or remaping fails - we probably should invoke previously insta=
lled handler
or just apply default action.
Konstantin

> > +}
> > +