RE: [RH72 Spectre] ibpb_enabled = 1 leads to hard LOCKUP under x86_64 host machine

From: Van De Ven, Arjan
Date: Sat Jan 20 2018 - 08:56:22 EST


well first of all don't use IBRS, use retpoline

and if Andrea says this was a known issue in their code then I think that closes the issue.




> -----Original Message-----
> From: David Woodhouse [mailto:dwmw2@xxxxxxxxxxxxx]
> Sent: Saturday, January 20, 2018 1:03 AM
> To: Hou Tao <houtao1@xxxxxxxxxx>; aarcange@xxxxxxxxxx; linux-
> kernel@xxxxxxxxxxxxxxx; Van De Ven, Arjan <arjan.van.de.ven@xxxxxxxxx>
> Cc: mingo@xxxxxxxxxx; Thomas Gleixner <tglx@xxxxxxxxxxxxx>;
> ak@xxxxxxxxxxxxxxx; dave.hansen@xxxxxxxxxxxxxxx; peterz@xxxxxxxxxxxxx;
> qiuxishi@xxxxxxxxxx; wangkefeng.wang@xxxxxxxxxx
> Subject: Re: [RH72 Spectre] ibpb_enabled = 1 leads to hard LOCKUP under
> x86_64 host machine
>
> On Sat, 2018-01-20 at 17:00 +0800, Hou Tao wrote:
> >
> > So has anyone encountered a similar problem before, and any suggestions
> > and directions for the hard LOCKUP problems ?
>
> Arjan, what is the Intel recommendation here?