From: Marc Zyngier <maz@kernel.org>
To: Oliver Upton <oliver.upton@linux.dev>
Cc: kvmarm@lists.linux.dev, Joey Gouly <joey.gouly@arm.com>,
Suzuki K Poulose <suzuki.poulose@arm.com>,
Zenghui Yu <yuzenghui@huawei.com>,
Mingwei Zhang <mizhang@google.com>,
Colton Lewis <coltonlewis@google.com>,
Alexandru Elisei <alexandru.elisei@arm.com>
Subject: Re: [PATCH 11/15] KVM: arm64: Use debug_owner to track if debug regs need save/restore
Date: Sat, 09 Nov 2024 22:37:49 +0000 [thread overview]
Message-ID: <87bjyot4n6.wl-maz@kernel.org> (raw)
In-Reply-To: <Zy-Zbj_BYovU5qch@linux.dev>
On Sat, 09 Nov 2024 17:18:38 +0000,
Oliver Upton <oliver.upton@linux.dev> wrote:
>
> On Sat, Nov 09, 2024 at 12:11:39PM +0000, Marc Zyngier wrote:
> > > static bool trap_debug_regs(struct kvm_vcpu *vcpu,
> > > struct sys_reg_params *p,
> > > const struct sys_reg_desc *r)
> > > {
> > > access_rw(vcpu, p, r);
> > > if (p->is_write)
> > > - vcpu_set_flag(vcpu, DEBUG_DIRTY);
> > >
> > > kvm_handle_debug_access(vcpu);
> >
> > Something has gone wrong here, and I don't think you wanted to make
> > the ownership conditional on the access being only a write.
>
> That's very much intentional (probably not clear enough in changelog). I
> don't think there's any value in special-casing this to writes.
Look again. You *are* special-casing it by only dropping the
vcpu_set_flag() call. Hint, the indentation is misleading.
M.
--
Without deviation from the norm, progress is not possible.
next prev parent reply other threads:[~2024-11-09 22:37 UTC|newest]
Thread overview: 36+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-11-08 22:24 [PATCH 00/15] KVM: arm64: Debug cleanups Oliver Upton
2024-11-08 22:24 ` [PATCH 01/15] KVM: arm64: Drop MDSCR_EL1_DEBUG_MASK Oliver Upton
2024-11-08 22:24 ` [PATCH 02/15] KVM: arm64: Get rid of __kvm_get_mdcr_el2() and related warts Oliver Upton
2024-11-11 11:00 ` Suzuki K Poulose
2024-11-12 7:22 ` Oliver Upton
2024-11-08 22:24 ` [PATCH 03/15] KVM: arm64: Track presence of SPE/TRBE in kvm_host_data instead of vCPU Oliver Upton
2024-11-11 13:47 ` Suzuki K Poulose
2024-11-11 15:58 ` Suzuki K Poulose
2024-11-11 16:09 ` James Clark
2024-11-11 18:17 ` Oliver Upton
2024-11-08 22:24 ` [PATCH 04/15] KVM: arm64: Move host SME/SVE tracking flags to host data Oliver Upton
2024-11-09 11:39 ` Marc Zyngier
2024-11-08 22:24 ` [PATCH 05/15] KVM: arm64: Evaluate debug owner at vcpu_load() Oliver Upton
2024-11-08 22:24 ` [PATCH 06/15] KVM: arm64: Advance debug_owner state machine for sysreg traps Oliver Upton
2024-11-09 11:47 ` Marc Zyngier
2024-11-08 22:24 ` [PATCH 07/15] KVM: arm64: Clean up KVM_SET_GUEST_DEBUG handler Oliver Upton
2024-11-08 22:24 ` [PATCH 08/15] KVM: arm64: Select debug state to save/restore based on debug owner Oliver Upton
2024-11-09 11:57 ` Marc Zyngier
2024-11-09 17:13 ` Oliver Upton
2024-11-08 22:24 ` [PATCH 09/15] KVM: arm64: Remove debug tracepoints Oliver Upton
2024-11-09 12:02 ` Marc Zyngier
2024-11-09 13:17 ` Marc Zyngier
2024-11-08 22:24 ` [PATCH 10/15] KVM: arm64: Remove vestiges of debug_ptr Oliver Upton
2024-11-08 22:24 ` [PATCH 11/15] KVM: arm64: Use debug_owner to track if debug regs need save/restore Oliver Upton
2024-11-09 12:11 ` Marc Zyngier
2024-11-09 17:18 ` Oliver Upton
2024-11-09 22:37 ` Marc Zyngier [this message]
2024-11-09 23:46 ` Oliver Upton
2024-11-08 22:24 ` [PATCH 12/15] KVM: arm64: Reload vCPU for accesses to OSLAR_EL1 Oliver Upton
2024-11-08 22:24 ` [PATCH 13/15] KVM: arm64: Compute MDCR_EL2 at vcpu_load() Oliver Upton
2024-11-09 12:28 ` Marc Zyngier
2024-11-08 22:24 ` [PATCH 14/15] KVM: arm64: Don't hijack guest context MDSCR_EL1 Oliver Upton
2024-11-09 12:59 ` Marc Zyngier
2024-11-08 22:24 ` [PATCH 15/15] KVM: arm64: Manage software step state at load/put Oliver Upton
2024-11-09 13:13 ` [PATCH 00/15] KVM: arm64: Debug cleanups Marc Zyngier
2024-11-09 17:08 ` Oliver Upton
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