From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id DBAE4C433EF for ; Mon, 13 Dec 2021 14:27:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239230AbhLMO1t (ORCPT ); Mon, 13 Dec 2021 09:27:49 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39956 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235055AbhLMO1s (ORCPT ); Mon, 13 Dec 2021 09:27:48 -0500 Received: from mail-ed1-x533.google.com (mail-ed1-x533.google.com [IPv6:2a00:1450:4864:20::533]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4EE7BC061574; Mon, 13 Dec 2021 06:27:48 -0800 (PST) Received: by mail-ed1-x533.google.com with SMTP id r25so52220891edq.7; Mon, 13 Dec 2021 06:27:48 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=sender:message-id:date:mime-version:user-agent:subject :content-language:to:cc:references:from:in-reply-to :content-transfer-encoding; bh=5uz2bkPs9pu4ybBTlw8INklC2IY/HyciJ34wdpnt1cA=; b=PZX8RlKlhtrHTBr3+MPycG9W385C0LeJWaMA/bcECVbKL8fJwdA2TQBbIXquRKbGM3 WvK/FsAUrwksaBfWtRpJI4Z9GCYNnvk5oY8VjL0g6G54dw+rAIi5x71fUTvOejFzT/Ax 7DIptUZfWjwlrKTC/lRDwnwGlLO0mimG8sGT9du08XyVPZo+eip10eapIVc+ctMork1j ZWOHGw28SBrczIIaQ9AdFurt1zBvxJ2kCjihXgguXRmA5c9AtV9tUAMRQgN/WTCLhhvU JHd2CbEtQMnwDDEUq/wWqdysSUeaEUv8VvBSCAFo3Q1pDsLSk2nCqYmLAjMs9rU5JyWC MXhw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:sender:message-id:date:mime-version:user-agent :subject:content-language:to:cc:references:from:in-reply-to :content-transfer-encoding; bh=5uz2bkPs9pu4ybBTlw8INklC2IY/HyciJ34wdpnt1cA=; b=SFO6AiLo7hMjmv94g3vS6u+QnQKwEWZTs10juzPurIfA3usr63UNRrIZ8i8JyvV1uF l43/cSjbvhsebZXTH/ccqhvMXzjuk7PiD8zYLgXMOEQ97yQ2yxAOy6guxusF250pgzRU fErM0nDUBDTtCnzCbb3Lbm4zWDPBMA/DurbHCpKAn3jalVbW4aL4DDn+5GFqrQevA//s wyRPY5Ga0U1ei1sWLXVOjIUii7GaB4iCNiq3CfIR1U8AsEq1bEHBU+sMejmGBtcUcSym iP3vZZL+7YEO8KQGEeQrMpKbEcrqbW/ppkAu4xGPMCODXHNbXrZczA+h94+rTtsJCR1H SdDA== X-Gm-Message-State: AOAM531QizpsmFYS6eH9neNVYOyijfpQnxBdk7tlhRrN/1SLkvzOArQ+ pHddQBLlr4MrpGlzHxtuxh8= X-Google-Smtp-Source: ABdhPJyZZvAP9DR71TNi/kbNtqFoG9VKoIhctK7pqYCRxr1qrpcJC++LKCj1kf4UQxfE0PrsodEZKw== X-Received: by 2002:a17:907:6e10:: with SMTP id sd16mr45440822ejc.158.1639405663099; Mon, 13 Dec 2021 06:27:43 -0800 (PST) Received: from ?IPV6:2001:b07:6468:f312:c8dd:75d4:99ab:290a? ([2001:b07:6468:f312:c8dd:75d4:99ab:290a]) by smtp.googlemail.com with ESMTPSA id f22sm6603789edf.93.2021.12.13.06.27.42 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Mon, 13 Dec 2021 06:27:42 -0800 (PST) Sender: Paolo Bonzini Message-ID: Date: Mon, 13 Dec 2021 15:27:41 +0100 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.2.0 Subject: Re: [PATCH MANUALSEL 5.15 4/9] KVM: SEV: do not take kvm->lock when destroying Content-Language: en-US To: Sasha Levin , linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Sean Christopherson , tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, x86@kernel.org, kvm@vger.kernel.org References: <20211213141944.352249-1-sashal@kernel.org> <20211213141944.352249-4-sashal@kernel.org> From: Paolo Bonzini In-Reply-To: <20211213141944.352249-4-sashal@kernel.org> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 12/13/21 15:19, Sasha Levin wrote: > From: Paolo Bonzini > > [ Upstream commit 10a37929efeb4c51a0069afdd537c4fa3831f6e5 ] > > Taking the lock is useless since there are no other references, > and there are already accesses (e.g. to sev->enc_context_owner) > that do not take it. So get rid of it. > > Reviewed-by: Sean Christopherson > Message-Id: <20211123005036.2954379-12-pbonzini@redhat.com> > Signed-off-by: Paolo Bonzini > Signed-off-by: Sasha Levin > --- > arch/x86/kvm/svm/sev.c | 4 ---- > 1 file changed, 4 deletions(-) > > diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c > index 134c4ea5e6ad8..ae8092f0d401e 100644 > --- a/arch/x86/kvm/svm/sev.c > +++ b/arch/x86/kvm/svm/sev.c > @@ -1842,8 +1842,6 @@ void sev_vm_destroy(struct kvm *kvm) > return; > } > > - mutex_lock(&kvm->lock); > - > /* > * Ensure that all guest tagged cache entries are flushed before > * releasing the pages back to the system for use. CLFLUSH will > @@ -1863,8 +1861,6 @@ void sev_vm_destroy(struct kvm *kvm) > } > } > > - mutex_unlock(&kvm->lock); > - > sev_unbind_asid(kvm, sev->handle); > sev_asid_free(sev); > } > This is cosmetic only, so NACK Paolo