linux-kernel - RE: [PATCH] arch/riscv: disable too many harts before pick main boot hart

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <MN2PR04MB60618CCE4EAE01B58D25CBCC8D890@MN2PR04MB6061.namprd04.prod.outlook.com>
Date:   Thu, 19 Sep 2019 10:55:05 +0000
From:   Anup Patel <Anup.Patel@....com>
To:     Paul Walmsley <paul.walmsley@...ive.com>,
        Xiang Wang <merle@...denedlinux.org>
CC:     "palmer@...ive.com" <palmer@...ive.com>,
        "aou@...s.berkeley.edu" <aou@...s.berkeley.edu>,
        "linux-riscv@...ts.infradead.org" <linux-riscv@...ts.infradead.org>,
        "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
        "citypw@...denedlinux.org" <citypw@...denedlinux.org>
Subject: RE: [PATCH] arch/riscv: disable too many harts before pick main boot
 hart



> -----Original Message-----
> From: linux-kernel-owner@...r.kernel.org <linux-kernel-
> owner@...r.kernel.org> On Behalf Of Paul Walmsley
> Sent: Thursday, September 19, 2019 3:56 PM
> To: Xiang Wang <merle@...denedlinux.org>
> Cc: palmer@...ive.com; aou@...s.berkeley.edu; linux-
> riscv@...ts.infradead.org; linux-kernel@...r.kernel.org;
> citypw@...denedlinux.org
> Subject: Re: [PATCH] arch/riscv: disable too many harts before pick main
> boot hart
> 
> On Fri, 6 Sep 2019, Xiang Wang wrote:
> 
> > From 12300865d1103618c9d4c375f7d7fbe601b6618c Mon Sep 17 00:00:00
> 2001
> > From: Xiang Wang <merle@...denedlinux.org>
> > Date: Fri, 6 Sep 2019 11:56:09 +0800
> > Subject: [PATCH] arch/riscv: disable too many harts before pick main
> > boot hart
> >
> > These harts with id greater than or equal to CONFIG_NR_CPUS need to be
> disabled.
> > But pick the main Hart can choose any one. So, before pick the main
> > hart, you need to disable the hart with id greater than or equal to
> CONFIG_NR_CPUS.
> >
> > Signed-off-by: Xiang Wang <merle@...denedlinux.org>
> 
> Thanks, here's what I'm planning to queue for v5.4-rc1.  Please let me know
> ASAP if you want to change the patch description.
> 
> 
> - Paul
> 
> From: Xiang Wang <merle@...denedlinux.org>
> Date: Fri, 6 Sep 2019 11:56:09 +0800
> Subject: [PATCH] arch/riscv: disable excess harts before picking main boot
> hart
> 
> Harts with id greater than or equal to CONFIG_NR_CPUS need to be
> disabled.  But the kernel can pick any hart as the main hart.  So,
> before picking the main hart, the kernel must disable harts with ids
> greater than or equal to CONFIG_NR_CPUS.
> 
> Signed-off-by: Xiang Wang <merle@...denedlinux.org>

You missed my Reviewed-by here.

Regards,
Anup

> Reviewed-by: Palmer Dabbelt <palmer@...ive.com>
> [paul.walmsley@...ive.com: updated to apply; cleaned up patch
>  description]
> Signed-off-by: Paul Walmsley <paul.walmsley@...ive.com>
> ---
>  arch/riscv/kernel/head.S | 8 +++++---
>  1 file changed, 5 insertions(+), 3 deletions(-)
> 
> diff --git a/arch/riscv/kernel/head.S b/arch/riscv/kernel/head.S
> index 15a9189f91ad..72f89b7590dd 100644
> --- a/arch/riscv/kernel/head.S
> +++ b/arch/riscv/kernel/head.S
> @@ -63,6 +63,11 @@ _start_kernel:
>  	li t0, SR_FS
>  	csrc CSR_SSTATUS, t0
> 
> +#ifdef CONFIG_SMP
> +	li t0, CONFIG_NR_CPUS
> +	bgeu a0, t0, .Lsecondary_park
> +#endif
> +
>  	/* Pick one hart to run the main boot sequence */
>  	la a3, hart_lottery
>  	li a2, 1
> @@ -154,9 +159,6 @@ relocate:
> 
>  .Lsecondary_start:
>  #ifdef CONFIG_SMP
> -	li a1, CONFIG_NR_CPUS
> -	bgeu a0, a1, .Lsecondary_park
> -
>  	/* Set trap vector to spin forever to help debug */
>  	la a3, .Lsecondary_park
>  	csrw CSR_STVEC, a3
> --
> 2.23.0