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Date:   Fri, 22 Jul 2022 11:48:31 +0100
From:   Oliver Upton <oliver.upton@linux.dev>
To:     Kalesh Singh <kaleshsingh@google.com>
Cc:     maz@kernel.org, mark.rutland@arm.com, broonie@kernel.org,
        madvenka@linux.microsoft.com, tabba@google.com, will@kernel.org,
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        yuzenghui@huawei.com, ardb@kernel.org,
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Subject: Re: [PATCH v5 00/17] KVM nVHE Hypervisor stack unwinder
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References: <20220721055728.718573-1-kaleshsingh@google.com>
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In-Reply-To: <20220721055728.718573-1-kaleshsingh@google.com>
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Hi Kalesh,

On Wed, Jul 20, 2022 at 10:57:11PM -0700, Kalesh Singh wrote:

[...]

> Kalesh Singh (17):
>   arm64: stacktrace: Add shared header for common stack unwinding code
>   arm64: stacktrace: Factor out on_accessible_stack_common()
>   arm64: stacktrace: Factor out unwind_next_common()
>   arm64: stacktrace: Handle frame pointer from different address spaces
>   arm64: stacktrace: Factor out common unwind()
>   arm64: stacktrace: Add description of stacktrace/common.h
>   KVM: arm64: On stack overflow switch to hyp overflow_stack
>   KVM: arm64: Add PROTECTED_NVHE_STACKTRACE Kconfig
>   KVM: arm64: Allocate shared pKVM hyp stacktrace buffers
>   KVM: arm64: Stub implementation of pKVM HYP stack unwinder
>   KVM: arm64: Stub implementation of non-protected nVHE HYP stack
>     unwinder
>   KVM: arm64: Save protected-nVHE (pKVM) hyp stacktrace
>   KVM: arm64: Prepare non-protected nVHE hypervisor stacktrace
>   KVM: arm64: Implement protected nVHE hyp stack unwinder
>   KVM: arm64: Implement non-protected nVHE hyp stack unwinder
>   KVM: arm64: Introduce pkvm_dump_backtrace()
>   KVM: arm64: Introduce hyp_dump_backtrace()

Adding a general comment on the organization of the series. I think for
the next spin it'd be good to organize the entire non-pKVM
implementation first, followed by the pKVM implementation. Otherwise,
reviewers need to jump around the series a lot in order to page in the
appropriate context.

I had mentioned this about the last two patches earlier, but after
grokking the stack I see the comment applies to the entire KVM portion
of the series.

--
Thanks,
Oliver