From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pj1-f73.google.com (mail-pj1-f73.google.com [209.85.216.73]) (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 7023528D83E for ; Sat, 14 Feb 2026 01:27:24 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.216.73 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1771032449; cv=none; b=HZ6GObUdU7HEfjTaO73aGaTTYWesxUAf07zQYJeA5eZGCzcGWYgOliHEMdjnA84pFScbUVCFFbRV/ujpgXD0v9rsdX2GF3qZPptqy5ER3jGK3dUX9r38/xWpJn0YHHxdVG2OqvV1+X1R0mzMJUMLNPC2J0/FX8azd/pbfalGUCg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1771032449; c=relaxed/simple; bh=hftPp1cgH316yfhw8k/dPrCnpI6uxskVDDg5/T2D/XQ=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=d2w/L7QMxu2HSYRcXCxX7zHRmFS6gidl+s1Ob0QKUJABR3MfaWnskUj+Czv+YsR6uML0UpDme6bGupNNoR6AHLFwmeQHoxNBFhlKVHUMoZZZBcWLAk8/8kI7OSyIH2AEjP7PcWyHdhpmtJNKkxQu+D33Wv90VjUh+rbBkQuqzuQ= 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=gNqdhUDU; arc=none smtp.client-ip=209.85.216.73 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="gNqdhUDU" Received: by mail-pj1-f73.google.com with SMTP id 98e67ed59e1d1-3561f5bd22eso1474591a91.2 for ; Fri, 13 Feb 2026 17:27:24 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1771032444; x=1771637244; darn=lists.linux.dev; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:reply-to:from:to:cc:subject:date:message-id:reply-to; bh=H80q9SD+282s080Ud0tbsBB2WQnuDfalKG9TFAGQvtU=; b=gNqdhUDUhCaMqFoCttB57OihSr1sW/YozUck1qYN1PnKDsPPKh6buqCcVRPfkG7nKJ VqQsZfTgYqS77DE0vWExN1j/OXNOg6f09IDyKJqgz1WRsl3Q7k6P80lWJJyyMBW8u2cR Qx+/D6lm4Z0r71znjRlBZ0ieJ0Vp272e0D0AdfQcZ3mGW6YL5cJWahu4HZ+flVkjxZyn JZhp5HY2amwWdVV7WhAvpRaJ5qNA87sIlV+SgZEb9m/cg8PnONp0d6TaXqrQ0+wLc0Wr Uso7+R2JqIClM7iA17fKWiakBAkG6IpnIemvAgALhjZvJjY7+Q7tPmzy9xqhPP41XVHA cc3A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1771032444; x=1771637244; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:reply-to:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=H80q9SD+282s080Ud0tbsBB2WQnuDfalKG9TFAGQvtU=; b=Vt+xozKEr0THRxEufgbQSPkTc+a0j8a0uR2lg4ZsnQQy84Mi70CSCNCMHGgfpBSr9x 2/H5FeexdCNt19GsAp+lap4gVo+O75Viu/tabbpG07tHv9PVOf368xqDb6Uamnz2IJo3 iZweEDd4OtkbRhicheXPbK6sox9s1p35AiP8xw+jZ91kTaBERBhJU/bxgJ62eEit8HSU Q/2dNtbE3+P+mdzgcX78iNQBYjkuQWUVcbSax4ie4b0P7x1ioqGfv3N8SaNpOxMBreBP qF+713t6QWSfCCrxESQCMowcYkVJbAhtI/ytUWZr2KB6Y3W0ikuTmUOQgh9xMP3eWDhZ Xf+w== X-Forwarded-Encrypted: i=1; AJvYcCVcPwR28UFRBr7thQ2KaBtt10dM0TTI0JqZR+0/ks6v7y4luvvl0218rbC1TbNAEDoCpdvK8wTEmHBo@lists.linux.dev X-Gm-Message-State: AOJu0Yymue0ggyiFxcbY0844VbezS9J4JYFrfCn7eWueL9p1NzieRtR1 Xc8/ZPYjIouvZXZeYqOUn/+Q0m3xpk+yoSBQavXxo59r49m35/oMruC1XiMjDh15bSqK75E1zpR etHSQCw== X-Received: from pgvt5.prod.google.com ([2002:a65:64c5:0:b0:c65:e24e:cef1]) (user=seanjc job=prod-delivery.src-stubby-dispatcher) by 2002:a05:6a20:43a5:b0:38e:9cc5:218c with SMTP id adf61e73a8af0-3946c8be39amr3465099637.54.1771032443485; Fri, 13 Feb 2026 17:27:23 -0800 (PST) Reply-To: Sean Christopherson Date: Fri, 13 Feb 2026 17:26:56 -0800 In-Reply-To: <20260214012702.2368778-1-seanjc@google.com> Precedence: bulk X-Mailing-List: linux-coco@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20260214012702.2368778-1-seanjc@google.com> X-Mailer: git-send-email 2.53.0.310.g728cabbaf7-goog Message-ID: <20260214012702.2368778-11-seanjc@google.com> Subject: [PATCH v3 10/16] x86/virt/tdx: Drop the outdated requirement that TDX be enabled in IRQ context From: Sean Christopherson To: Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, Kiryl Shutsemau , Peter Zijlstra , Arnaldo Carvalho de Melo , Namhyung Kim , Sean Christopherson , Paolo Bonzini Cc: linux-kernel@vger.kernel.org, linux-coco@lists.linux.dev, kvm@vger.kernel.org, linux-perf-users@vger.kernel.org, Chao Gao , Xu Yilun , Dan Williams Content-Type: text/plain; charset="UTF-8" Remove TDX's outdated requirement that per-CPU enabling be done via IPI function call, which was a stale artifact leftover from early versions of the TDX enablement series. The requirement that IRQs be disabled should have been dropped as part of the revamped series that relied on a the KVM rework to enable VMX at module load. In other words, the kernel's "requirement" was never a requirement at all, but instead a reflection of how KVM enabled VMX (via IPI callback) when the TDX subsystem code was merged. Note, accessing per-CPU information is safe even without disabling IRQs, as tdx_online_cpu() is invoked via a cpuhp callback, i.e. from a per-CPU thread. Link: https://lore.kernel.org/all/ZyJOiPQnBz31qLZ7@google.com Signed-off-by: Sean Christopherson --- arch/x86/kvm/vmx/tdx.c | 9 +-------- arch/x86/virt/vmx/tdx/tdx.c | 4 ---- 2 files changed, 1 insertion(+), 12 deletions(-) diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c index 0c790eb0bfa6..582469118b79 100644 --- a/arch/x86/kvm/vmx/tdx.c +++ b/arch/x86/kvm/vmx/tdx.c @@ -3294,17 +3294,10 @@ int tdx_gmem_max_mapping_level(struct kvm *kvm, kvm_pfn_t pfn, bool is_private) static int tdx_online_cpu(unsigned int cpu) { - unsigned long flags; - int r; - /* Sanity check CPU is already in post-VMXON */ WARN_ON_ONCE(!(cr4_read_shadow() & X86_CR4_VMXE)); - local_irq_save(flags); - r = tdx_cpu_enable(); - local_irq_restore(flags); - - return r; + return tdx_cpu_enable(); } static int tdx_offline_cpu(unsigned int cpu) diff --git a/arch/x86/virt/vmx/tdx/tdx.c b/arch/x86/virt/vmx/tdx/tdx.c index 5ce4ebe99774..dfd82fac0498 100644 --- a/arch/x86/virt/vmx/tdx/tdx.c +++ b/arch/x86/virt/vmx/tdx/tdx.c @@ -148,8 +148,6 @@ static int try_init_module_global(void) * global initialization SEAMCALL if not done) on local cpu to make this * cpu be ready to run any other SEAMCALLs. * - * Always call this function via IPI function calls. - * * Return 0 on success, otherwise errors. */ int tdx_cpu_enable(void) @@ -160,8 +158,6 @@ int tdx_cpu_enable(void) if (!boot_cpu_has(X86_FEATURE_TDX_HOST_PLATFORM)) return -ENODEV; - lockdep_assert_irqs_disabled(); - if (__this_cpu_read(tdx_lp_initialized)) return 0; -- 2.53.0.310.g728cabbaf7-goog