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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 5A7B0C44536 for ; Thu, 22 Jan 2026 11:22:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Type:Cc:To:From: Subject:Message-ID:References:Mime-Version:In-Reply-To:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=GbpJOUsj+jmFdKgKTCHaN8Qj3FdeUCxTExCcXcyJF/8=; b=O4+DUdVeZrmh0JaBu1+lh2TUwt 4u/GKXrkdNgNvMpcAojwffDm+wemuy+uW7nZyqS4EVfj7wiZUGAtfQVLAp0VXgcA1e8c8Kcr1rM/2 EeT+Zq/bSscKZRLBzoc/L1E7Lcix3Zo0LyUZ6KjccL9e/PJy/N1+Sq5E4VoLLnUsxJiINSeckoQds Ajz4xMMUsSFhoV7TyUT7fOFVc9SeT2qUkVTWGPMZJ2bHA2CxuvHOdQ/e+V4+tOAUgBIwRERcpbiUq 7FpiW4GEc8nHHJRsBzE8sWS8G6tmnTP6AJuZEw4F9KqEVuqlrB5YIBWuQa/o9DGKXHc0v++XUgqhJ h6lbcSkg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1vislg-00000006x1t-3w3Z; Thu, 22 Jan 2026 11:22:28 +0000 Received: from mail-wr1-x449.google.com ([2a00:1450:4864:20::449]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1visla-00000006wz4-2gU9 for linux-arm-kernel@lists.infradead.org; Thu, 22 Jan 2026 11:22:23 +0000 Received: by mail-wr1-x449.google.com with SMTP id ffacd0b85a97d-43065ad16a8so537989f8f.1 for ; Thu, 22 Jan 2026 03:22:21 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1769080940; x=1769685740; darn=lists.infradead.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=GbpJOUsj+jmFdKgKTCHaN8Qj3FdeUCxTExCcXcyJF/8=; b=GSvOkqBfWKXSjd2cYuiRuh0XqI76EnyVEOCcJ2Avf9T0wkysdokIv3JNJL3ExxBtDq ldfqO/zdiOaAyKeXpwcze7jX5meUp2YBaDBfFUvExn0YkfXMMVBj2PWRsKlDtNb5R8wc eH2i8H2N5+AmMA42lyBqjnYzA94xAeYKd+QOpkzsxooMJO3oinuwYNWftOcXwz+C4dM8 1otgdvoJv60MWaRq3JYMkDEX6FlolzRC5D4HqR+LGa0vaXPp5vAkLJ7GzET8f4eNRRq0 q6aIGPyeahrpSPx1NRLMRVeBrASnGPcuJyd3GeswARbcauDkqf7H9jl3675RR6wlGzWu CesQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1769080940; x=1769685740; 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=GbpJOUsj+jmFdKgKTCHaN8Qj3FdeUCxTExCcXcyJF/8=; b=pmdhwns5bfyA8PxNrw92/ZFWBVhDyjttsHuxpiNg87IM4qizt2Pv0f5hbKEE6TzKCx aRVrpwv9ElriPc9UmaHYSwnKwMKZEbXIZprCeEpPk4QQpQwaEpkqgrnRlG5n1uoggTuz 4miLgdAdtL/y57XcrMP9I+fkQUISukgYTsfiW9q9wG9PyuN0bFZVSv98cU3iqYtFnoJo GpE79eB+3GX47/1MwzW49KKQzdarL2ocUgvXqe99PDzrx+Oa25wc/1ubn0uf8u6WprWV PKpfCj1UCHyZzB0QkCnI3BS8MM1GdstjC2uBeI6CnOBYya6u9ae2BK1Oobhafa4p4WX9 EjXQ== X-Forwarded-Encrypted: i=1; AJvYcCUIOJLCFD1DTkKWvVvUHMRrBcrjoyczOmsfiCAUHxTQPVnNysGSEmO3NIFsP41v/oIIH71mLlMqixkbKAdN0cQL@lists.infradead.org X-Gm-Message-State: AOJu0YwfKrtZ34sz9YFECYByBBK9bJoHrcSowEo/hCegO+NMm4O8OHyO Y+uq4cM929dgN+LGAqlbF+ymHjgmONU/fENHCsXCh0nq5xEbCrB5e+3h8ivnAal9v4E4KIxpaE+ kKw== X-Received: from wrbcp14.prod.google.com ([2002:a05:6000:400e:b0:430:f2e6:376e]) (user=tabba job=prod-delivery.src-stubby-dispatcher) by 2002:a5d:5552:0:b0:435:97b2:a9b with SMTP id ffacd0b85a97d-43597b20ad9mr9445342f8f.37.1769080939974; Thu, 22 Jan 2026 03:22:19 -0800 (PST) Date: Thu, 22 Jan 2026 11:22:15 +0000 In-Reply-To: <20260122112218.531948-1-tabba@google.com> Mime-Version: 1.0 References: <20260122112218.531948-1-tabba@google.com> X-Mailer: git-send-email 2.52.0.457.g6b5491de43-goog Message-ID: <20260122112218.531948-2-tabba@google.com> Subject: [PATCH v3 1/4] KVM: arm64: Remove dead code resetting HCR_EL2 for pKVM From: Fuad Tabba To: kvmarm@lists.linux.dev, linux-arm-kernel@lists.infradead.org Cc: maz@kernel.org, oliver.upton@linux.dev, joey.gouly@arm.com, suzuki.poulose@arm.com, yuzenghui@huawei.com, catalin.marinas@arm.com, will@kernel.org, tabba@google.com Content-Type: text/plain; charset="UTF-8" X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260122_032222_680662_43C2937B X-CRM114-Status: UNSURE ( 9.40 ) X-CRM114-Notice: Please train this message. X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org The pKVM lifecycle does not support tearing down the hypervisor and returning to the hyp stub once initialized. The transition to protected mode is one-way. Consequently, the code path in hyp-init.S responsible for resetting EL2 registers (triggered by kexec or hibernation) is unreachable in protected mode. Remove the dead code handling HCR_EL2 reset for ARM64_KVM_PROTECTED_MODE. No functional change intended. Signed-off-by: Fuad Tabba --- arch/arm64/kvm/hyp/nvhe/hyp-init.S | 5 ----- 1 file changed, 5 deletions(-) diff --git a/arch/arm64/kvm/hyp/nvhe/hyp-init.S b/arch/arm64/kvm/hyp/nvhe/hyp-init.S index aada42522e7b..0d42eedc7167 100644 --- a/arch/arm64/kvm/hyp/nvhe/hyp-init.S +++ b/arch/arm64/kvm/hyp/nvhe/hyp-init.S @@ -260,11 +260,6 @@ reset: msr sctlr_el2, x5 isb -alternative_if ARM64_KVM_PROTECTED_MODE - mov_q x5, HCR_HOST_NVHE_FLAGS - msr_hcr_el2 x5 -alternative_else_nop_endif - /* Install stub vectors */ adr_l x5, __hyp_stub_vectors msr vbar_el2, x5 -- 2.52.0.457.g6b5491de43-goog