Re: [PATCH v3 3/3] KVM: arm64: Don't pass host_debug_state to BRBE world-switch routines

[Will Deacon <will@kernel.org>]

On Thu, Mar 26, 2026 at 02:12:13PM +0000, Will Deacon wrote:
> Now that the SPE and BRBE nVHE world-switch routines operate on the
> host_debug_state directly, tweak the BRBE code to do the same for
> consistency.
> 
> This is purely cosmetic.
> 
> Cc: Marc Zyngier <maz@kernel.org>
> Cc: Oliver Upton <oupton@kernel.org>
> Cc: James Clark <james.clark@linaro.org>
> Cc: Leo Yan <leo.yan@arm.com>
> Cc: Suzuki K Poulose <suzuki.poulose@arm.com>
> Cc: Fuad Tabba <tabba@google.com>
> Cc: Alexandru Elisei <alexandru.elisei@arm.com>
> Tested-by: Fuad Tabba <tabba@google.com>
> Reviewed-by: Fuad Tabba <tabba@google.com>
> Signed-off-by: Will Deacon <will@kernel.org>
> ---
>  arch/arm64/kvm/hyp/nvhe/debug-sr.c | 12 +++++++-----
>  1 file changed, 7 insertions(+), 5 deletions(-)
> 
> diff --git a/arch/arm64/kvm/hyp/nvhe/debug-sr.c b/arch/arm64/kvm/hyp/nvhe/debug-sr.c
> index 84bc80f4e36b..50413171bd1a 100644
> --- a/arch/arm64/kvm/hyp/nvhe/debug-sr.c
> +++ b/arch/arm64/kvm/hyp/nvhe/debug-sr.c
> @@ -156,9 +156,9 @@ static void __trace_switch_to_host(void)
>  			  *host_data_ptr(host_debug_state.trfcr_el1));
>  }
>  
> -static void __debug_save_brbe(u64 *brbcr_el1)
> +static void __debug_save_brbe(void)
>  {
> -	*brbcr_el1 = 0;
> +	u64 *brbcr_el1 = host_data_ptr(host_debug_state.brbcr_el1);

Oh no, I've been sashiko'd!

The above is definitely not "purely cosmetic" and I should retain the
'*brbcr_el1 = 0; ' line.

Will