From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pg1-f201.google.com (mail-pg1-f201.google.com [209.85.215.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id D09873148CD for ; Mon, 23 Feb 2026 16:40:21 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.215.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1771864824; cv=none; b=GzBtUx/tWkeWc1gS2Ksl/W2OBkc2ayIgG9o23aYlTTbk6qIN1VqwJ7wrCILxP0VVRGanp28Qz59pSUzbxq9LeYzJ0qN7QJtKdscjEXxNhFBqcCHNqItSltS5jWHv0NCMbCVHrM41SQuS6ZtdHaLCkkdLLrTW9wBvr0M2V+UG6oU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1771864824; c=relaxed/simple; bh=IXJhAAH1/nmIyhl+YBK57kQ2alnGFS9TAjMkhdnb+3s=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=dqtEvN2RKqLxqpQzGClMyMbQCiSKnDM4kSrf1BPN/faCBSzzAT5vyEdlg6BaEduc6QVvWxQBabVSb2mwZY+CqWK8NEwIUvDlli8FN38pHDpIYWgyZxq5onmunm0IQbjbOePRKVuwPO9i5QHeD32SBYdzb1RXD+eBsRaiS0+O+wU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--seanjc.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=qpD9R9Tp; arc=none smtp.client-ip=209.85.215.201 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--seanjc.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="qpD9R9Tp" Received: by mail-pg1-f201.google.com with SMTP id 41be03b00d2f7-b630753cc38so28051556a12.1 for ; Mon, 23 Feb 2026 08:40:21 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1771864821; x=1772469621; darn=vger.kernel.org; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=ZRtHqCOflJjuPuiCBSIsHs0ADNxbSUOiJ4HAHkLUWyE=; b=qpD9R9Tp0iRXgJB9LWTSr1kD7uwTsK4NNVck1Eum3lHKA6pJaOD5xYYfWAlGNu3T1a 0m6abhsLoxTsW1mHX/LMpzwkscBTp0aJ7bxgJTFmiSRoIJoJg2qOBIfU5hBgR/XLf5ZI a44dXN+u3G9hFhcVwAuln5rAsO3+1gxZIuZtIDrI3dhDxfuXtg7vvZWuL7LST3paZh8z Q32NxfedTW9UUiSp7eO3+dryeAI8xA51u8q3JaX1pW66iU0P9oNNw+UbIuouuZMcRFTw RXF/erVmIGugrqdsc2cwGWqVYgXFpdJs/d/L/mg0Lr4GmH+/9eLLMxD1hG0H0nmnOSiT yGgg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1771864821; x=1772469621; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=ZRtHqCOflJjuPuiCBSIsHs0ADNxbSUOiJ4HAHkLUWyE=; b=H95unJCzKXwLsFaHUBBodI4PPl/0ZtdE67IF6Kx7IN9iVe2SeTiGhjzGuvaHIo2Iq3 h/lRseQnZuZLlF1rmXH5zLtERaqRfQdtDy4yeEL0JbmIUo29VSId6LRwTRAYYX8txZBu qohSh/Xk/odIN59FmWHn57ikbJt6CQ7Mga28fP0UGFu2eoDvVh/s1bGaXMOmPpiWrSSI 7bfN6idGD/YnIHpZEzKGdrbziqjUcJU8G+fxqcndMYcNlsrvSWhnKitwL6lmB0a+5W+2 GbXbzt/OlAZeXFqBhUZHTnJIkX1yWp3lfke+6buDQpOEL9EWuycxcJYcZt9rDzBC+l3F jGEw== X-Forwarded-Encrypted: i=1; AJvYcCX/vfS7iTwuE5drjFFBjnsAKqpMWHxkAHr83IlelT2UVkOjcL9+zLrFrvgVXuwMZpmz7NTHVY11KsodqNQ=@vger.kernel.org X-Gm-Message-State: AOJu0YwCvAWK1Kf7nRHiLL0j2xGUbRsWWncyGpe6+thXTLDxAwGPBCiM CA5wJt6/X9RNeQJQb7tpYFxUAXWlRnHVIxoNDGtSIxGqjiYkcRiRp+85hBQD6GxIaxjNtL8uzb+ wgDkUsQ== X-Received: from pgbcp13.prod.google.com ([2002:a05:6a02:400d:b0:c48:d03e:cc20]) (user=seanjc job=prod-delivery.src-stubby-dispatcher) by 2002:a05:6a21:9987:b0:366:19e9:f43 with SMTP id adf61e73a8af0-39545e527a0mr8858315637.6.1771864820987; Mon, 23 Feb 2026 08:40:20 -0800 (PST) Date: Mon, 23 Feb 2026 08:40:19 -0800 In-Reply-To: <20260223162900.772669-4-tycho@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20260223162900.772669-1-tycho@kernel.org> <20260223162900.772669-4-tycho@kernel.org> Message-ID: Subject: Re: [PATCH 3/4] crypto/ccp: support setting RAPL_DIS in SNP_INIT_EX From: Sean Christopherson To: Tycho Andersen Cc: Ashish Kalra , Tom Lendacky , John Allen , Herbert Xu , Paolo Bonzini , Shuah Khan , "David S. Miller" , linux-crypto@vger.kernel.org, linux-kernel@vger.kernel.org, kvm@vger.kernel.org, linux-kselftest@vger.kernel.org Content-Type: text/plain; charset="us-ascii" On Mon, Feb 23, 2026, Tycho Andersen wrote: > From: "Tycho Andersen (AMD)" > > The kernel allows setting the RAPL_DIS policy bit, but had no way to set Please actually say what RAPL_DIS is and does, and explain why this is the correct approach. I genuinely have no idea what the impact of this patch is, (beyond disabling something, obviously). > the RAPL_DIS bit during SNP_INIT_EX. Setting the policy bit would always > result in: > > [ 898.840286] ccp 0000:a9:00.5: sev command 0xa0 failed (0x00000007) > > Allow setting the RAPL_DIS bit during SNP_INIT_EX via a module parameter. > If the hardware does not support RAPL_DIS, log and disable the module > parameter. > > Signed-off-by: Tycho Andersen (AMD) > --- > drivers/crypto/ccp/sev-dev.c | 14 ++++++++++++++ > 1 file changed, 14 insertions(+) > > diff --git a/drivers/crypto/ccp/sev-dev.c b/drivers/crypto/ccp/sev-dev.c > index 096f993974d1..362126453ef0 100644 > --- a/drivers/crypto/ccp/sev-dev.c > +++ b/drivers/crypto/ccp/sev-dev.c > @@ -75,6 +75,10 @@ static bool psp_init_on_probe = true; > module_param(psp_init_on_probe, bool, 0444); > MODULE_PARM_DESC(psp_init_on_probe, " if true, the PSP will be initialized on module init. Else the PSP will be initialized on the first command requiring it"); > > +static bool rapl_disable; > +module_param(rapl_disable, bool, 0444); > +MODULE_PARM_DESC(rapl_disable, " if true, the RAPL_DIS bit will be set during INIT_EX if supported"); > + > #if IS_ENABLED(CONFIG_PCI_TSM) > static bool sev_tio_enabled = true; > module_param_named(tio, sev_tio_enabled, bool, 0444); > @@ -1428,6 +1432,16 @@ static int __sev_snp_init_locked(int *error, unsigned int max_snp_asid) > data.max_snp_asid = max_snp_asid; > } > > + if (rapl_disable) { > + if (sev->snp_feat_info_0.ecx & SNP_RAPL_DISABLE_SUPPORTED) { > + data.rapl_dis = 1; > + } else { > + dev_info(sev->dev, > + "SEV: RAPL_DIS requested, but not supported"); > + rapl_disable = false; > + } > + } > + > data.init_rmp = 1; > data.list_paddr_en = 1; > data.list_paddr = __psp_pa(snp_range_list); > -- > 2.53.0 >