From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pl1-f201.google.com (mail-pl1-f201.google.com [209.85.214.201]) (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 66E571EB1AE for ; Thu, 27 Feb 2025 02:19:33 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.214.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1740622776; cv=none; b=BrU854OL8Whb4lst3NqzGloResDfCUWpdG5lw2loDACZf7vozus6u8lLYf8tJWpxh81g7O7lR2Qp+uFM9LtOW6bu2E6rOcN+PR8yNZC6VtepNMWAmva6uaBrhRJgt9tWVV6/b+rwL939hwDpqpJ4lIwMruT1yO19kAyfRFZObu4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1740622776; c=relaxed/simple; bh=P0O5mmkSnDe0SpsR7bTvnzJu0+xYte77F3QT24wbpm0=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=M6KfPdHlJ9TGs4b9RlRhC4enfMKL73f7mFMu773upBam+F9zTpzMq4OQdrCCblSpu/gW6NNiohQwDKBvpaIkAVX1/1miy+cz7EWVpT67L+9pYVqtM9n3hrxmVM5JsoXUvJBQLKJBPeM4LImmt+woFf/32sf7H2oyCUGwobmwsFw= 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=4MEraazr; arc=none smtp.client-ip=209.85.214.201 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="4MEraazr" Received: by mail-pl1-f201.google.com with SMTP id d9443c01a7336-21f6cb3097bso9346525ad.3 for ; Wed, 26 Feb 2025 18:19:33 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1740622773; x=1741227573; 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=iUPGjlm6EABKAwlimnT9Yj0uy9Y0kc3vikfZk6zMyUM=; b=4MEraazrPpH2deogFNyPM2zmleFoewK18sJnfMPVHXcdv/kiR+E1vz+Pd1fELSHPJS 9t5nSSy20f5lye383UjWcMkBKLS6rBOozh9nC4z4R0pNOnXwaIHK4flSBNGMabIZYEJM XI2s0vflf7SFhDtay0JOnjQNKuQGS75hqI741PbjcHMQUW5gOqfuAjAt9lc8tjIkkkTs r7nt6qa0ozzIU+hpS4TaIcwbLzy+3w+DQeEQ+Q3Sal9ov0xFIoY3MXdMQNDf/b4ZutFo LIC2RfNoy1wIWDZJNFWp0wWcRsVl192voVQe/io8w4Sp3CJlAUb6QhyW1Ryb+Ss96VG9 walA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1740622773; x=1741227573; 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=iUPGjlm6EABKAwlimnT9Yj0uy9Y0kc3vikfZk6zMyUM=; b=DY5u+/AqRQ0eugPwa3xDflMpGGUs4aU5usWjCIMZZdXx8QiLfATkpQJdOdRxBTUr3x d6iKwzaJsyBQase2J92jaYNJbQNAd+IvGaXXwcNdRElLRi00TFLpd8r5xgnmnNtOoWDM oyIgE87XQiGXAKZoimNG4Ag9miMNJHMX00LNG3LEQ1y+u/hPkFQr79eiBzw0S16OgcCS x8+SPV7KOVDIhN/hEe4keUYwjfTUv/uSO0jDq6SlYKXv0Roio9Rlvue+jpkiBr/wxvs2 VsNkRhY42XDapBcujq3IMBx5QqFSwSpocta+I/b9k6/9P6de5zJmS4r5KRR0ht89Dq5U dakA== X-Forwarded-Encrypted: i=1; AJvYcCU6vnLIEqDhIyCn9+zDhfA676TqwlxUs0HeYLqyhy5LQkfyxNOVxmm9QnvK7p0wLK+xRRTXgIPEUwiI@lists.linux.dev X-Gm-Message-State: AOJu0YxcT5SZAAGoRnBEh/373LSAdK3zJqm8M2mfVHLsg+6IgfMa1F/j Ju5MuHHZAaUlAJu3+yYTUz6cjoJra7Vc+I4lTPvuQrPDMB9p6JD6/VIBi92nxj82keIpuQIqJPD R4Q== X-Google-Smtp-Source: AGHT+IESbVD77xvo7C+ciGzHtrGqGL0Rj+DzLIK2/TaODo5QawXajXsWSJTUc7OSugj7U0H5GgKBaGLNEhI= X-Received: from pfld12.prod.google.com ([2002:a05:6a00:198c:b0:732:7e28:8f7d]) (user=seanjc job=prod-delivery.src-stubby-dispatcher) by 2002:a05:6a00:1813:b0:732:6221:7180 with SMTP id d2e1a72fcca58-73426c943c4mr38161657b3a.5.1740622772828; Wed, 26 Feb 2025 18:19:32 -0800 (PST) Reply-To: Sean Christopherson Date: Wed, 26 Feb 2025 18:18:33 -0800 In-Reply-To: <20250227021855.3257188-1-seanjc@google.com> Precedence: bulk X-Mailing-List: linux-coco@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20250227021855.3257188-1-seanjc@google.com> X-Mailer: git-send-email 2.48.1.711.g2feabab25a-goog Message-ID: <20250227021855.3257188-18-seanjc@google.com> Subject: [PATCH v2 17/38] x86/tsc: WARN if TSC sched_clock save/restore used with PV sched_clock From: Sean Christopherson To: Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, "Kirill A. Shutemov" , Paolo Bonzini , Sean Christopherson , Juergen Gross , "K. Y. Srinivasan" , Haiyang Zhang , Wei Liu , Dexuan Cui , Ajay Kaher , Jan Kiszka , Andy Lutomirski , Peter Zijlstra , Daniel Lezcano , John Stultz Cc: linux-kernel@vger.kernel.org, linux-coco@lists.linux.dev, kvm@vger.kernel.org, virtualization@lists.linux.dev, linux-hyperv@vger.kernel.org, xen-devel@lists.xenproject.org, Tom Lendacky , Nikunj A Dadhania Content-Type: text/plain; charset="UTF-8" Now that all PV clocksources override the sched_clock save/restore hooks when overriding sched_clock, WARN if the "default" TSC hooks are invoked when using a PV sched_clock, e.g. to guard against regressions. Signed-off-by: Sean Christopherson --- arch/x86/kernel/tsc.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/x86/kernel/tsc.c b/arch/x86/kernel/tsc.c index 472d6c71d3a5..5501d76243c8 100644 --- a/arch/x86/kernel/tsc.c +++ b/arch/x86/kernel/tsc.c @@ -990,7 +990,7 @@ static unsigned long long cyc2ns_suspend; void tsc_save_sched_clock_state(void) { - if (!sched_clock_stable()) + if (!sched_clock_stable() || WARN_ON_ONCE(!using_native_sched_clock())) return; cyc2ns_suspend = sched_clock(); @@ -1010,7 +1010,7 @@ void tsc_restore_sched_clock_state(void) unsigned long flags; int cpu; - if (!sched_clock_stable()) + if (!sched_clock_stable() || WARN_ON_ONCE(!using_native_sched_clock())) return; local_irq_save(flags); -- 2.48.1.711.g2feabab25a-goog