Re: [PATCH] LoongArch: add spectre boundry for syscall dispatch table

[Bibo Mao]

On 2026/4/2 下午10:36, Greg Kroah-Hartman wrote:
> On Wed, Mar 25, 2026 at 09:53:09AM +0100, Greg Kroah-Hartman wrote:
> > On Wed, Mar 25, 2026 at 11:26:29AM +0800, Xi Ruoyao wrote:
> > > On Tue, 2026-03-24 at 17:30 +0100, Greg Kroah-Hartman wrote:
> > > > The LoongArch syscall number is directly controlled by userspace, but
> > > > does not have a array_index_nospec() boundry to prevent access past
> > > > the
> > > > syscall function pointer tables.
> > > >
> > > > Cc: Huacai Chen <chenhuacai@xxxxxxxxxx>
> > > > Cc: WANG Xuerui <kernel@xxxxxxxxxx>
> > > > Assisted-by: gkh_clanker_2000
> > > > Cc: stable <stable@xxxxxxxxxx>
> > > > Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
> > > > ---
> > > > My scripts caught this as I think LoongArch is vulnerable to the
> > >
> > > There's no evidence.  The kernel currently report all LoongArch
> > > processors invulnerable to spectre V1 via cpuinfo.
> >
> > Where is that?  In the sysfs files, or in the actual silicon testing?
> >
> > > So NAK unless there's a reproducer of spectre V1 on LoongArch.  If so
> > > we'd also need to adjust the cpuinfo output.
> >
> > I really thought this cpu was vulnerable to this, but if the companies
> > say it isn't, then great, but reports like this:
> > 	https://cc-sw.com/chinese-loongarch-architecture-evaluation-part-3-of-3/
> > say that the silicon is vulnerable.  So, which is it?
>
> Any thoughts about this?
co-ask though it is hard to decide :(

Regards
Bibo Mao
> thanks,
>
> greg k-h