Messages in this thread | | | Date | Fri, 13 Sep 2019 12:04:32 -0700 (PDT) | Subject | Re: arch/riscv: disable too many harts before pick main boot hart | From | Palmer Dabbelt <> |
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On Thu, 05 Sep 2019 23:51:15 PDT (-0700), merle@hardenedlinux.org wrote: > From 12300865d1103618c9d4c375f7d7fbe601b6618c Mon Sep 17 00:00:00 2001 > From: Xiang Wang <merle@hardenedlinux.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@hardenedlinux.org> > --- > 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 0f1ba17e476f..cfffea38eb17 100644 > --- a/arch/riscv/kernel/head.S > +++ b/arch/riscv/kernel/head.S > @@ -63,6 +63,11 @@ _start_kernel: > li t0, SR_FS > csrc 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
It would be better to decouple the hart masks from NR_CPUS, as there's really no reason for these to be the same.
Reviewed-by: Palmer Dabbelt <palmer@sifive.com>
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