From: Alexandru Elisei <alexandru.elisei@arm.com>
To: Marc Zyngier <maz@kernel.org>,
linux-arm-kernel@lists.infradead.org,
kvmarm@lists.cs.columbia.edu, kvm@vger.kernel.org
Cc: Will Deacon <will@kernel.org>, kernel-team@android.com
Subject: Re: [PATCH 7/8] KVM: arm64: Simplify __kvm_enable_ssbs()
Date: Mon, 2 Nov 2020 15:30:29 +0000 [thread overview]
Message-ID: <efe49392-b8ae-76fa-b581-d7ec8db2cac7@arm.com> (raw)
In-Reply-To: <20201026095116.72051-8-maz@kernel.org>
Hi Marc,
On 10/26/20 9:51 AM, Marc Zyngier wrote:
> Move the setting of SSBS directly into the HVC handler, using
> the C helpers rather than the inline asssembly code.
>
> Signed-off-by: Marc Zyngier <maz@kernel.org>
> ---
> arch/arm64/include/asm/kvm_asm.h | 2 --
> arch/arm64/include/asm/sysreg.h | 1 +
> arch/arm64/kvm/hyp/nvhe/hyp-main.c | 6 +++++-
> arch/arm64/kvm/hyp/nvhe/sysreg-sr.c | 11 -----------
> 4 files changed, 6 insertions(+), 14 deletions(-)
>
> diff --git a/arch/arm64/include/asm/kvm_asm.h b/arch/arm64/include/asm/kvm_asm.h
> index 54387ccd1ab2..a542c422a036 100644
> --- a/arch/arm64/include/asm/kvm_asm.h
> +++ b/arch/arm64/include/asm/kvm_asm.h
> @@ -189,8 +189,6 @@ extern void __kvm_timer_set_cntvoff(u64 cntvoff);
>
> extern int __kvm_vcpu_run(struct kvm_vcpu *vcpu);
>
> -extern void __kvm_enable_ssbs(void);
> -
> extern u64 __vgic_v3_get_ich_vtr_el2(void);
> extern u64 __vgic_v3_read_vmcr(void);
> extern void __vgic_v3_write_vmcr(u32 vmcr);
> diff --git a/arch/arm64/include/asm/sysreg.h b/arch/arm64/include/asm/sysreg.h
> index d52c1b3ce589..c9423f36e05c 100644
> --- a/arch/arm64/include/asm/sysreg.h
> +++ b/arch/arm64/include/asm/sysreg.h
> @@ -461,6 +461,7 @@
>
> #define SYS_PMCCFILTR_EL0 sys_reg(3, 3, 14, 15, 7)
>
> +#define SYS_SCTLR_EL2 sys_reg(3, 4, 1, 0, 0)
> #define SYS_ZCR_EL2 sys_reg(3, 4, 1, 2, 0)
> #define SYS_DACR32_EL2 sys_reg(3, 4, 3, 0, 0)
> #define SYS_SPSR_EL2 sys_reg(3, 4, 4, 0, 0)
> diff --git a/arch/arm64/kvm/hyp/nvhe/hyp-main.c b/arch/arm64/kvm/hyp/nvhe/hyp-main.c
> index 2af8a5e902af..5125e934da22 100644
> --- a/arch/arm64/kvm/hyp/nvhe/hyp-main.c
> +++ b/arch/arm64/kvm/hyp/nvhe/hyp-main.c
> @@ -58,7 +58,11 @@ static void handle___kvm_timer_set_cntvoff(struct kvm_cpu_context *host_ctxt)
>
> static void handle___kvm_enable_ssbs(struct kvm_cpu_context *host_ctxt)
> {
> - __kvm_enable_ssbs();
> + u64 tmp;
> +
> + tmp = read_sysreg_el2(SYS_SCTLR);
> + tmp |= SCTLR_ELx_DSSBS;
> + write_sysreg_el2(tmp, SYS_SCTLR);
This looks identical to me to the inline assembly version:
Reviewed-by: Alexandru Elisei <alexandru.elisei@arm.com>
Thanks,
Alex
> }
>
> static void handle___vgic_v3_get_ich_vtr_el2(struct kvm_cpu_context *host_ctxt)
> diff --git a/arch/arm64/kvm/hyp/nvhe/sysreg-sr.c b/arch/arm64/kvm/hyp/nvhe/sysreg-sr.c
> index 88a25fc8fcd3..29305022bc04 100644
> --- a/arch/arm64/kvm/hyp/nvhe/sysreg-sr.c
> +++ b/arch/arm64/kvm/hyp/nvhe/sysreg-sr.c
> @@ -33,14 +33,3 @@ void __sysreg_restore_state_nvhe(struct kvm_cpu_context *ctxt)
> __sysreg_restore_user_state(ctxt);
> __sysreg_restore_el2_return_state(ctxt);
> }
> -
> -void __kvm_enable_ssbs(void)
> -{
> - u64 tmp;
> -
> - asm volatile(
> - "mrs %0, sctlr_el2\n"
> - "orr %0, %0, %1\n"
> - "msr sctlr_el2, %0"
> - : "=&r" (tmp) : "L" (SCTLR_ELx_DSSBS));
> -}
_______________________________________________
kvmarm mailing list
kvmarm@lists.cs.columbia.edu
https://lists.cs.columbia.edu/mailman/listinfo/kvmarm
next prev parent reply other threads:[~2020-11-02 15:29 UTC|newest]
Thread overview: 15+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-10-26 9:51 [PATCH 0/8] KVM: arm64: Host EL2 entry improvements Marc Zyngier
2020-10-26 9:51 ` [PATCH 1/8] KVM: arm64: Don't corrupt tpidr_el2 on failed HVC call Marc Zyngier
2020-10-26 14:36 ` Quentin Perret
2020-10-26 9:51 ` [PATCH 2/8] KVM: arm64: Remove leftover kern_hyp_va() in nVHE TLB invalidation Marc Zyngier
2020-11-02 13:30 ` Alexandru Elisei
2020-10-26 9:51 ` [PATCH 3/8] KVM: arm64: Drop useless PAN setting on host EL1 to EL2 transition Marc Zyngier
2020-10-26 10:48 ` Vladimir Murzin
2020-10-26 9:51 ` [PATCH 4/8] KVM: arm64: Add kimg_hyp_va() helper Marc Zyngier
2020-10-26 9:51 ` [PATCH 5/8] KVM: arm64: Turn host HVC handling into a dispatch table Marc Zyngier
2020-11-02 14:19 ` Alexandru Elisei
2020-10-26 9:51 ` [PATCH 6/8] KVM: arm64: Patch kimage_voffset instead of loading the EL1 value Marc Zyngier
2020-10-26 9:51 ` [PATCH 7/8] KVM: arm64: Simplify __kvm_enable_ssbs() Marc Zyngier
2020-11-02 15:30 ` Alexandru Elisei [this message]
2020-10-26 9:51 ` [PATCH 8/8] KVM: arm64: Avoid repetitive stack access on host EL1 to EL2 exception Marc Zyngier
2020-11-02 16:28 ` Alexandru Elisei
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=efe49392-b8ae-76fa-b581-d7ec8db2cac7@arm.com \
--to=alexandru.elisei@arm.com \
--cc=kernel-team@android.com \
--cc=kvm@vger.kernel.org \
--cc=kvmarm@lists.cs.columbia.edu \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=maz@kernel.org \
--cc=will@kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).