From nobody Sun Feb 8 23:04:14 2026 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 EADC52BE057 for ; Fri, 17 Oct 2025 00:33:23 +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=1760661206; cv=none; b=DzT+eq8Ygvv7xqV/AJKsPHJcqemM0dkDQ7qk/KUl2iiT7vmDJUkaT3jEsy9Se8/srCQhHoS8CigfJ7D/q5v1AQyKDllsw7XVEmbcjq924dZiP5K8JKjc/5qcr2t4KcpOhLOtr8DvHN7/x6Bt/jf6b4ou1l0Qt1TIW6/M7ruxvv0= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760661206; c=relaxed/simple; bh=M6cFRGQS8meCCuYW0/U+4dFHJMyHGWBHr9QMgQL+DJ0=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=mmqHtCdjFQtsZtkmnK/OGby8fpwAF8H8XOWAqd7vgoYONIiBcNrvPfnyuEROlFLiJ04WHP2wuZNVH4LeE2AewyP4qYAxIIyd3Iyucnmyi5CzSjKttKatXQReNcWT4m3ZtWtIow4rMcUcucge5pgYb2kCRpVaJ0bvqeGSOctaYYM= 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=JG8w4U4N; 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="JG8w4U4N" Received: by mail-pj1-f73.google.com with SMTP id 98e67ed59e1d1-3304def7909so1195965a91.3 for ; Thu, 16 Oct 2025 17:33:23 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1760661203; x=1761266003; darn=vger.kernel.org; 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=jejy5GHiX1n5ZzK7FS/SwKAPXTIMDzw65QOVqYwFQBI=; b=JG8w4U4Niq55dlrwX/1lGDMW9qhuGwx2MPE04ytJyxTMKWU4aqUHtxNQ4nsCFJyNaB nnLs9iS7YXdN6SneGXWiV3Xd/9zi5q0PUx3Qt+FQvzCuABxjrT5v1VIT32yCNVFCGaZy gBS0LzGGlhEY6lpXnBlfzMh/dUCNpC0mrk1b+2S1ioHkzTfkL2MpfEzO9ipUEkwTWt9O gzpvqgARSoJm5RtnX2Rrg7g6EWJE4oZNHga1deTKV1kRu09blFhE3JFnEbC4iT4bx1h9 T9zImFJj9V8gNd8S2jasDPTlFPWeS6JGAX8WM1gZtwFVDWR0QTU2j/91uNMKIy1ocUeZ i1Bw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1760661203; x=1761266003; 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=jejy5GHiX1n5ZzK7FS/SwKAPXTIMDzw65QOVqYwFQBI=; b=qqH2BJHorPdG8DIZoGMkUGiKqvUk21blQfEjGiHvX8tchVQKMpMk2EmV5K69JbJFMp g2GXCmmNScuJzdp3GY9GIgjgcJxhBwyIVxc2uKebJhX0RY3D4xURezYrE7DaTcKCA2pq pYzF4D6TZ8EAVvTvAOzj3pfQXsxPgTfeFyQHQDcqNgHt5nogPq+Q1A+H6zIUQoTnCIzy s5NyrH7WW7B/e1d6zzgXBcJiMBXplCXffIaQKIRlBIk/XKeQiW0acu5LoIVLS0aGGFVo msHXxY+bI+pPKqgp3InX2ZdP59sK9SNA/GsJbloJPTWDvXT8H3R3/NfkZ1AuY5wl2gEn 9lVw== X-Forwarded-Encrypted: i=1; AJvYcCUqLoQDBKnouP/ThpT4IjgBquEIrjs98zaAPiHJcgJCLcC7k45Mu9LbZ/OrIxbL7RPTQ8WjXKPA5aI0XGI=@vger.kernel.org X-Gm-Message-State: AOJu0Yy/sQVFzDFIYS/Mnjjtw1U/s8sv+RE0G99PI4AJr6hCHR9akxFp gqyss5tQBoHxuH2r3nvAC58XkH8AcBPf5cYJ7ErmWRaH5FO8IOdL4a+8U7Mv5MvuUulm3F1yCFP bmvsCqA== X-Google-Smtp-Source: AGHT+IFl8lCxI7RawbIX2CACJWbI5vFGM8HhgndqIpbMEKI2O7QrNwa82jxnXWK9S77FfTXYSbFZaN83qL4= X-Received: from pjqx20.prod.google.com ([2002:a17:90a:b014:b0:338:3e6b:b835]) (user=seanjc job=prod-delivery.src-stubby-dispatcher) by 2002:a17:90b:3c02:b0:32c:38b0:593e with SMTP id 98e67ed59e1d1-33bcf85ffa4mr1903883a91.5.1760661203423; Thu, 16 Oct 2025 17:33:23 -0700 (PDT) Reply-To: Sean Christopherson Date: Thu, 16 Oct 2025 17:32:38 -0700 In-Reply-To: <20251017003244.186495-1-seanjc@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20251017003244.186495-1-seanjc@google.com> X-Mailer: git-send-email 2.51.0.858.gf9c4a03a3a-goog Message-ID: <20251017003244.186495-21-seanjc@google.com> Subject: [PATCH v3 20/25] KVM: TDX: Add macro to retry SEAMCALLs when forcing vCPUs out of guest From: Sean Christopherson To: Marc Zyngier , Oliver Upton , Tianrui Zhao , Bibo Mao , Huacai Chen , Madhavan Srinivasan , Anup Patel , Paul Walmsley , Palmer Dabbelt , Albert Ou , Christian Borntraeger , Janosch Frank , Claudio Imbrenda , Sean Christopherson , Paolo Bonzini , "Kirill A. Shutemov" Cc: linux-arm-kernel@lists.infradead.org, kvmarm@lists.linux.dev, kvm@vger.kernel.org, loongarch@lists.linux.dev, linux-mips@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, kvm-riscv@lists.infradead.org, linux-riscv@lists.infradead.org, x86@kernel.org, linux-coco@lists.linux.dev, linux-kernel@vger.kernel.org, Ira Weiny , Kai Huang , Michael Roth , Yan Zhao , Vishal Annapurve , Rick Edgecombe , Ackerley Tng , Binbin Wu Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Add a macro to handle kicking vCPUs out of the guest and retrying SEAMCALLs on -EBUSY instead of providing small helpers to be used by each SEAMCALL. Wrapping the SEAMCALLs in a macro makes it a little harder to tease out which SEAMCALL is being made, but significantly reduces the amount of copy+paste code and makes it all but impossible to leave an elevated wait_for_sept_zap. Signed-off-by: Sean Christopherson --- arch/x86/kvm/vmx/tdx.c | 72 ++++++++++++++---------------------------- 1 file changed, 23 insertions(+), 49 deletions(-) diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c index f6782b0ffa98..2e2dab89c98f 100644 --- a/arch/x86/kvm/vmx/tdx.c +++ b/arch/x86/kvm/vmx/tdx.c @@ -294,25 +294,24 @@ static inline void tdx_disassociate_vp(struct kvm_vcp= u *vcpu) vcpu->cpu =3D -1; } =20 -static void tdx_no_vcpus_enter_start(struct kvm *kvm) -{ - struct kvm_tdx *kvm_tdx =3D to_kvm_tdx(kvm); - - lockdep_assert_held_write(&kvm->mmu_lock); - - WRITE_ONCE(kvm_tdx->wait_for_sept_zap, true); - - kvm_make_all_cpus_request(kvm, KVM_REQ_OUTSIDE_GUEST_MODE); -} - -static void tdx_no_vcpus_enter_stop(struct kvm *kvm) -{ - struct kvm_tdx *kvm_tdx =3D to_kvm_tdx(kvm); - - lockdep_assert_held_write(&kvm->mmu_lock); - - WRITE_ONCE(kvm_tdx->wait_for_sept_zap, false); -} +#define tdh_do_no_vcpus(tdh_func, kvm, args...) \ +({ \ + struct kvm_tdx *__kvm_tdx =3D to_kvm_tdx(kvm); \ + u64 __err; \ + \ + lockdep_assert_held_write(&kvm->mmu_lock); \ + \ + __err =3D tdh_func(args); \ + if (unlikely(tdx_operand_busy(__err))) { \ + WRITE_ONCE(__kvm_tdx->wait_for_sept_zap, true); \ + kvm_make_all_cpus_request(kvm, KVM_REQ_OUTSIDE_GUEST_MODE); \ + \ + __err =3D tdh_func(args); \ + \ + WRITE_ONCE(__kvm_tdx->wait_for_sept_zap, false); \ + } \ + __err; \ +}) =20 /* TDH.PHYMEM.PAGE.RECLAIM is allowed only when destroying the TD. */ static int __tdx_reclaim_page(struct page *page) @@ -1711,14 +1710,7 @@ static void tdx_track(struct kvm *kvm) if (unlikely(kvm_tdx->state !=3D TD_STATE_RUNNABLE)) return; =20 - err =3D tdh_mem_track(&kvm_tdx->td); - if (unlikely(tdx_operand_busy(err))) { - /* After no vCPUs enter, the second retry is expected to succeed */ - tdx_no_vcpus_enter_start(kvm); - err =3D tdh_mem_track(&kvm_tdx->td); - tdx_no_vcpus_enter_stop(kvm); - } - + err =3D tdh_do_no_vcpus(tdh_mem_track, kvm, &kvm_tdx->td); TDX_BUG_ON(err, TDH_MEM_TRACK, kvm); =20 kvm_make_all_cpus_request(kvm, KVM_REQ_OUTSIDE_GUEST_MODE); @@ -1770,14 +1762,8 @@ static void tdx_sept_remove_private_spte(struct kvm = *kvm, gfn_t gfn, if (KVM_BUG_ON(level !=3D PG_LEVEL_4K, kvm)) return; =20 - err =3D tdh_mem_range_block(&kvm_tdx->td, gpa, tdx_level, &entry, &level_= state); - if (unlikely(tdx_operand_busy(err))) { - /* After no vCPUs enter, the second retry is expected to succeed */ - tdx_no_vcpus_enter_start(kvm); - err =3D tdh_mem_range_block(&kvm_tdx->td, gpa, tdx_level, &entry, &level= _state); - tdx_no_vcpus_enter_stop(kvm); - } - + err =3D tdh_do_no_vcpus(tdh_mem_range_block, kvm, &kvm_tdx->td, gpa, + tdx_level, &entry, &level_state); if (TDX_BUG_ON_2(err, TDH_MEM_RANGE_BLOCK, entry, level_state, kvm)) return; =20 @@ -1792,20 +1778,8 @@ static void tdx_sept_remove_private_spte(struct kvm = *kvm, gfn_t gfn, * with other vcpu sept operation. * Race with TDH.VP.ENTER due to (0-step mitigation) and Guest TDCALLs. */ - err =3D tdh_mem_page_remove(&kvm_tdx->td, gpa, tdx_level, &entry, - &level_state); - - if (unlikely(tdx_operand_busy(err))) { - /* - * The second retry is expected to succeed after kicking off all - * other vCPUs and prevent them from invoking TDH.VP.ENTER. - */ - tdx_no_vcpus_enter_start(kvm); - err =3D tdh_mem_page_remove(&kvm_tdx->td, gpa, tdx_level, &entry, - &level_state); - tdx_no_vcpus_enter_stop(kvm); - } - + err =3D tdh_do_no_vcpus(tdh_mem_page_remove, kvm, &kvm_tdx->td, gpa, + tdx_level, &entry, &level_state); if (TDX_BUG_ON_2(err, TDH_MEM_PAGE_REMOVE, entry, level_state, kvm)) return; =20 --=20 2.51.0.858.gf9c4a03a3a-goog