linux-kernel - Re: [PATCH v8 24/28] KVM: arm64: Add trace reset to the pKVM hyp

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <875xarfjzd.wl-maz@kernel.org>
Date: Sun, 30 Nov 2025 18:33:58 +0000
From: Marc Zyngier <maz@...nel.org>
To: Vincent Donnefort <vdonnefort@...gle.com>
Cc: rostedt@...dmis.org,
	mhiramat@...nel.org,
	mathieu.desnoyers@...icios.com,
	linux-trace-kernel@...r.kernel.org,
	oliver.upton@...ux.dev,
	joey.gouly@....com,
	suzuki.poulose@....com,
	yuzenghui@...wei.com,
	kvmarm@...ts.linux.dev,
	linux-arm-kernel@...ts.infradead.org,
	jstultz@...gle.com,
	qperret@...gle.com,
	will@...nel.org,
	aneesh.kumar@...nel.org,
	kernel-team@...roid.com,
	linux-kernel@...r.kernel.org
Subject: Re: [PATCH v8 24/28] KVM: arm64: Add trace reset to the pKVM hyp

On Fri, 07 Nov 2025 09:38:36 +0000,
Vincent Donnefort <vdonnefort@...gle.com> wrote:
> 

[...]

> +int __pkvm_reset_tracing(unsigned int cpu)
> +{
> +	int ret = 0;
> +
> +	if (cpu >= hyp_nr_cpus)
> +		return -EINVAL;
> +
> +	hyp_spin_lock(&trace_buffer.lock);
> +
> +	if (hyp_trace_buffer_loaded(&trace_buffer))
> +		ret = simple_ring_buffer_reset(per_cpu_ptr(trace_buffer.simple_rbs, cpu));
> +	else
> +		ret = -ENODEV;
> +
> +	hyp_spin_unlock(&trace_buffer.lock);
> +
> +	return ret;

nit; there is no case where the 'ret' default value can be used.
Either drop the init or make it so that the default value is
meaningful (-ENODEV).

Thanks,

	M.

-- 
Jazz isn't dead. It just smells funny.