From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pl1-f202.google.com (mail-pl1-f202.google.com [209.85.214.202]) (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 6559220B80B for ; Sat, 13 Jun 2026 00:20:39 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.214.202 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781310042; cv=none; b=LJX32jHhxQ5tG6gfsBSDx+2YJchK4tz+c03rMxymD3dp6KRDMFgLb/+EzHQxqoG2vRtJYhmBAKnRLDpkaCGmu3DyNGMmMOzx4og3ug1sn4WDDkGE0Vr0jfCB42l6nNCK4sjL9/y+RSsuY0RiHGln4w4mbWFBEt2B7nCYxr6e45k= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781310042; c=relaxed/simple; bh=JV1d9mTxVyznuvXEHzHbiL6DP5o6g8Jk2shnAwWUw40=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=RT/eE7yUiK7hbVp3/cUov2qTUuz04SU0DYVRTcPVFo9pIxIP0scrawDMFhUiDCNLdoOvhTR63a6OE7dLALvdRc5rNEQloG90+7DdZEypG+L4rdjWfwkTfaLTgYNP24+Xl8tBBcuPXoIsDc7CaxMPF0jg7ZafylRY8VlPND49Zfg= 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=dzwFjX9G; arc=none smtp.client-ip=209.85.214.202 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="dzwFjX9G" Received: by mail-pl1-f202.google.com with SMTP id d9443c01a7336-2beff6b6e74so20147665ad.1 for ; Fri, 12 Jun 2026 17:20:39 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20251104; t=1781310039; x=1781914839; 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=O+I565ELukpP/rjfHIhv+TORYO3S6R2jcA7ns197jWA=; b=dzwFjX9GY0CSkCBXRt/58WrcYLpeiLuHg9QoPiD33dU/zLbtS1UHo9/qa+OgFBZz/q T+vlISLH6h55IZf12nxNjvdPKQ75S6dvNXhy1UczUOB0UvIsBZbnUbe65IdXrpEDZ2qP 2lyTuDrd0t1J/0uB8TOuBYw4LVtxeACHc9OFeJnmR1yJNGMSfEvVZocpllGiwTEzF/Di OPd1XkFptI35D/zAI7wbeLlXMkoX2s+BHkgMqFluEa5KwT9UNkUYBRApU/IMHDGOPEwO mlu0jdeCCRcXrFDRkojlq0cxjfDPC6yKHMLwzHcY5Z+J3VcLyhK08Mmo/Z9kdlVDNXF5 y2Bg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1781310039; x=1781914839; 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=O+I565ELukpP/rjfHIhv+TORYO3S6R2jcA7ns197jWA=; b=CK/3X4ZK+sBMzNFADgPOH38dSByFnhVgPcbqYefBjzYqxtHYFUnmT0A/bjqvTHsvqN 7Vk3x91k+t54X7CeCCqY7ApNp1QGaNddWOzohEGXzC0c3hFUUfsS0l/h1PcMqteGYwsg dGN8UnQ2ACe9grLe0gY6aj1f+0sZfFfjHxXLFN72nx/U1Vk6ZqwvgHeqRa5TyeCk/IHh 6yu5RgNCTm/hT194+H918V4m0JVZp+bB0TNDUlFuKAF/DQo+KoSsX19o8rwgxGLLkW9j AZm4vJNyKoRecQWY8EkO3FZT4v8FXfhT75b3ONkzFk1t12Y+qtsQWcykhJQGR9JhspgE bdgQ== X-Forwarded-Encrypted: i=1; AFNElJ87kf7GD31/q1fMuwNwmWGYFp+EUoWGVdKcTFAY8BXhQtcbbhnDSmvY+D0igagfNxNHG2fylFOwcYfWlsU=@vger.kernel.org X-Gm-Message-State: AOJu0Yx8lzM8kZoS8Yd0JtsBG/rQLtgtCcVSx8oePB4HDkDFq9fb6qIT FK/vhyq+iQf8XiAEhWrxQMMu/DaxRIuKrts5rmKilc3/Yj0U57W7zPuS2LLptFux76GEvpAzN/p Okz90tw== X-Received: from plbjb12.prod.google.com ([2002:a17:903:258c:b0:2b2:425f:b4f1]) (user=seanjc job=prod-delivery.src-stubby-dispatcher) by 2002:a17:903:1248:b0:2c1:69cb:4423 with SMTP id d9443c01a7336-2c4111b8e7cmr56455115ad.14.1781310038540; Fri, 12 Jun 2026 17:20:38 -0700 (PDT) Reply-To: Sean Christopherson Date: Fri, 12 Jun 2026 17:20:15 -0700 In-Reply-To: <20260613002031.745413-1-seanjc@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20260613002031.745413-1-seanjc@google.com> X-Mailer: git-send-email 2.54.0.1136.gdb2ca164c4-goog Message-ID: <20260613002031.745413-5-seanjc@google.com> Subject: [PATCH v7 04/20] KVM: selftests: Initialize the default/global pRNG during kvm_selftest_init() From: Sean Christopherson To: Paolo Bonzini , Marc Zyngier , Oliver Upton , Sean Christopherson Cc: Joey Gouly , Steffen Eiden , Suzuki K Poulose , Zenghui Yu , kvm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, kvmarm@lists.linux.dev, linux-kernel@vger.kernel.org, David Matlack , Josh Hilke Content-Type: text/plain; charset="UTF-8" Initialize the default kvm_rng during selftest initialization so that the pRNG can be used by tests before creating a VM. As pointed out by Sashiko, failure to actually initialize the generate makes it decidedly not random. Signed-off-by: Sean Christopherson --- tools/testing/selftests/kvm/lib/kvm_util.c | 18 +++++++++++------- 1 file changed, 11 insertions(+), 7 deletions(-) diff --git a/tools/testing/selftests/kvm/lib/kvm_util.c b/tools/testing/selftests/kvm/lib/kvm_util.c index 875030c22d07..1016865d3f7a 100644 --- a/tools/testing/selftests/kvm/lib/kvm_util.c +++ b/tools/testing/selftests/kvm/lib/kvm_util.c @@ -24,6 +24,13 @@ u32 kvm_random_seed; struct kvm_random_state kvm_rng; static u32 last_kvm_seed; +static void kvm_seed_rng(u32 seed) +{ + kvm_random_seed = last_kvm_seed = seed; + pr_info("Random seed: 0x%x\n", kvm_random_seed); + kvm_rng = new_kvm_random_state(kvm_random_seed); +} + static size_t vcpu_mmap_sz(void); int __open_path_or_exit(const char *path, int flags, const char *enoent_help) @@ -515,11 +522,9 @@ struct kvm_vm *__vm_create(struct vm_shape shape, u32 nr_runnable_vcpus, slot0 = memslot2region(vm, 0); ucall_init(vm, slot0->region.guest_phys_addr + slot0->region.memory_size); - if (kvm_random_seed != last_kvm_seed) { - pr_info("Random seed: 0x%x\n", kvm_random_seed); - last_kvm_seed = kvm_random_seed; - } - kvm_rng = new_kvm_random_state(kvm_random_seed); + if (kvm_random_seed != last_kvm_seed) + kvm_seed_rng(kvm_random_seed); + sync_global_to_guest(vm, kvm_rng); kvm_arch_vm_post_create(vm, nr_runnable_vcpus); @@ -2279,8 +2284,7 @@ void __attribute((constructor)) kvm_selftest_init(void) sigaction(SIGILL, &sig_sa, NULL); sigaction(SIGFPE, &sig_sa, NULL); - kvm_random_seed = last_kvm_seed = random(); - pr_info("Random seed: 0x%x\n", kvm_random_seed); + kvm_seed_rng(random()); kvm_selftest_arch_init(); } -- 2.54.0.1136.gdb2ca164c4-goog