Re: [PATCH 2/3] MIPS: cpu-probe: Vulnerabilities for MIPS cores

From: Huacai Chen <chenhuacai@kernel.org>
To: Jiaxun Yang <jiaxun.yang@flygoat.com>
Cc: "open list:MIPS" <linux-mips@vger.kernel.org>,
	"Thomas Bogendoerfer" <tsbogend@alpha.franken.de>,
	"Serge Semin" <Sergey.Semin@baikalelectronics.ru>,
	"WANG Xuerui" <git@xen0n.name>,
	"Alexey Malahov" <Alexey.Malahov@baikalelectronics.ru>,
	"Paul Burton" <paulburton@kernel.org>,
	"周琰杰 (Zhou Yanjie)" <zhouyanjie@wanyeetech.com>,
	"Tiezhu Yang" <yangtiezhu@loongson.cn>,
	"Paul Cercueil" <paul@crapouillou.net>,
	"YunQiang Su" <syq@debian.org>,
	"Liangliang Huang" <huanglllzu@gmail.com>,
	LKML <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH 2/3] MIPS: cpu-probe: Vulnerabilities for MIPS cores
Date: Thu, 31 Dec 2020 08:31:41 +0800	[thread overview]
Message-ID: <CAAhV-H7xP03NnpQPiP7jH3DH3DnoRnZqLWdtCm9eun7B_ems=A@mail.gmail.com> (raw)
In-Reply-To: <20201230032314.10042-2-jiaxun.yang@flygoat.com>

Reviewed-by: Huacai Chen <chenhuacai@kernel.org>

On Wed, Dec 30, 2020 at 11:25 AM Jiaxun Yang <jiaxun.yang@flygoat.com> wrote:
>
> Accorading to MIPS's announcement[1], only P5600 and P6600 is
> affected by spectre v1 and v2, other cores are not affected.
>
> So we mark vulnerabilities states for MIPS cores as known and
> set P5600 and P6600 as vulnerable.
>
> [1]: https://www.mips.com/blog/mips-response-on-speculative-execution-and-side-channel-vulnerabilities/
>
> Signed-off-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
> ---
>  arch/mips/kernel/cpu-probe.c | 5 +++++
>  1 file changed, 5 insertions(+)
>
> diff --git a/arch/mips/kernel/cpu-probe.c b/arch/mips/kernel/cpu-probe.c
> index 03adeed58efb..2460783dbdb1 100644
> --- a/arch/mips/kernel/cpu-probe.c
> +++ b/arch/mips/kernel/cpu-probe.c
> @@ -1688,6 +1688,9 @@ static inline void cpu_probe_legacy(struct cpuinfo_mips *c, unsigned int cpu)
>  static inline void cpu_probe_mips(struct cpuinfo_mips *c, unsigned int cpu)
>  {
>         c->writecombine = _CACHE_UNCACHED_ACCELERATED;
> +       c->vulnerabilities |= MIPS_VULNBL_MELTDOWN |
> +                             MIPS_VULNBL_SPECTRE_V1 | MIPS_VULNBL_SPECTRE_V2;
> +
>         switch (c->processor_id & PRID_IMP_MASK) {
>         case PRID_IMP_QEMU_GENERIC:
>                 c->writecombine = _CACHE_UNCACHED;
> @@ -1794,10 +1797,12 @@ static inline void cpu_probe_mips(struct cpuinfo_mips *c, unsigned int cpu)
>         case PRID_IMP_P5600:
>                 c->cputype = CPU_P5600;
>                 __cpu_name[cpu] = "MIPS P5600";
> +               c->vulnerable |= MIPS_VULNBL_SPECTRE_V1 | MIPS_VULNBL_SPECTRE_V2;
>                 break;
>         case PRID_IMP_P6600:
>                 c->cputype = CPU_P6600;
>                 __cpu_name[cpu] = "MIPS P6600";
> +               c->vulnerable |= MIPS_VULNBL_SPECTRE_V1 | MIPS_VULNBL_SPECTRE_V2;
>                 break;
>         case PRID_IMP_I6400:
>                 c->cputype = CPU_I6400;
> --
> 2.30.0
>