linux-kernel - Re: [PATCH v6 08/16] KVM: x86/pmu: Add IA32_DS

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: <3b13359c-5b7a-f103-74ff-1f57389db181@linux.intel.com>
Date:   Mon, 17 May 2021 07:50:02 -0700
From:   Andi Kleen <ak@...ux.intel.com>
To:     Peter Zijlstra <peterz@...radead.org>,
        Like Xu <like.xu@...ux.intel.com>
Cc:     Paolo Bonzini <pbonzini@...hat.com>,
        Borislav Petkov <bp@...en8.de>,
        Sean Christopherson <seanjc@...gle.com>,
        Vitaly Kuznetsov <vkuznets@...hat.com>,
        Wanpeng Li <wanpengli@...cent.com>,
        Jim Mattson <jmattson@...gle.com>,
        Joerg Roedel <joro@...tes.org>, weijiang.yang@...el.com,
        Kan Liang <kan.liang@...ux.intel.com>, wei.w.wang@...el.com,
        eranian@...gle.com, liuxiangdong5@...wei.com,
        linux-kernel@...r.kernel.org, x86@...nel.org, kvm@...r.kernel.org
Subject: Re: [PATCH v6 08/16] KVM: x86/pmu: Add IA32_DS_AREA MSR emulation to
 support guest DS


On 5/17/2021 6:26 AM, Peter Zijlstra wrote:
> On Tue, May 11, 2021 at 10:42:06AM +0800, Like Xu wrote:
>> @@ -3897,6 +3898,8 @@ static struct perf_guest_switch_msr *intel_guest_get_msrs(int *nr, void *data)
>>   {
>>   	struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events);
>>   	struct perf_guest_switch_msr *arr = cpuc->guest_switch_msrs;
>> +	struct debug_store *ds = __this_cpu_read(cpu_hw_events.ds);
>> +	struct kvm_pmu *pmu = (struct kvm_pmu *)data;
> You can do without the cast, this is C, 'void *' silently casts to any
> other pointer type.

FWIW doing the C++ like casts for void * is fairly standard C coding 
style. I generally prefer it too for better documentation. K&R is 
written this way.

-Andi (my last email on this topic to avoid any bike shedding)