From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pf1-f201.google.com (mail-pf1-f201.google.com [209.85.210.201]) (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 15BB3379993 for ; Thu, 16 Apr 2026 22:44:51 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.210.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776379493; cv=none; b=ZLsm64VLq8Zs4HEtS163TfO31XSvun4JA+GBGv9LS84ve7YD+nYhC40Mna/RszLNRSzA/w8ZAqJq0jpLQ3/1OzldV7wqjtRkpGwStv2v9x1ulHaRnwq8Y7A28wah/WtmjCJG+d77e2zLghggC9aae7eryVR39amJ179COrgaBI0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776379493; c=relaxed/simple; bh=QnH1vIimESyZ2peW1iohZ3MwmBA4oBxKLRs7rK4wSqQ=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=ggxgkqFzE3B4lND3H3/xoRJ9Rw0U+HQ/q18by+vTa0KfWPOOLqbf9y6RPP/OHxjU/mZ0Znk+1FdgLoK0bTypiBHvRU3hXvpPejSWb9jyVi/wGOJm+5DwBVMH4s9rGLJtCfE4z/UlLafkQI0rjtpn/kVZ+QCDZ+/jRoV4ISC1Xeo= 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=VeIywNGF; arc=none smtp.client-ip=209.85.210.201 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="VeIywNGF" Received: by mail-pf1-f201.google.com with SMTP id d2e1a72fcca58-82f7bec24fdso47220b3a.2 for ; Thu, 16 Apr 2026 15:44:51 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20251104; t=1776379491; x=1776984291; darn=vger.kernel.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=UqyYEqZgyMpoZKxskZj0QRqQl7ttahHyrPikYOVHCGs=; b=VeIywNGFDT898urzHsB6Lhv0CzlE8C3vn6rrp3ax65KnTTLVOjOmQaJ+bco7wSJcEK Uy2LteuxTCZUjkfGmcCfIm4Fo2uEZTOoWx5DyDzyt9YbtQhMuczlsGBBysKy9fqF8fpu KecMu0Mc4aRkDSV5sL7F5BhQtELHwHFx5LOSL/h6sLPYcGPdO68JwgPnKMwqygpU5OsU wYtHN1iyi0qbTfX9FV81jWlwUJHqQnESeK1b9u3YR1ZmbdLLxZZNcW/3Swyvej0rCDDe 9ZQDd3gYL35i9oiaMKBf1YXy9Vm18CoXnTB4wWFJQSeoqAdWfBeUctSDwor4lSHE2cal jfBw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1776379491; x=1776984291; 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=UqyYEqZgyMpoZKxskZj0QRqQl7ttahHyrPikYOVHCGs=; b=Kp2uInOW4DakQ+y/rxOmgth5lJchfv/KXyz+7LnyGUfkcKV5oqpkYZ7vZ9KD3mN/76 x8Lx1qBFOyp+9Abm2EFtYq/xajpbGjB4i1iAsWwOkQafQ/NFy93I2cSeOo2HpbUiK8dR dXqzrCOvcCTgnr5y7eUXEW6/ChdN3nBb8Vcku6I5KOoZF1+RUVxbn6VM/f9bSiBbFXTH ibJbd2tbLyMjf8fxSISak5RiOCH6l0KNgcEl4QXn4ZNY+T23eHMNYjgErpws9PEwa9AL Js1rdx/U66tk6+oJ1AMDL5qBcLdxAGgYdtBqALiSyKJfLex3jpv1EHyctv/HKV52qmvb FYZA== X-Forwarded-Encrypted: i=1; AFNElJ9G5KYr+gAYre/AHQ6Sgj0zz/8jHVSqvjS85Ro1yf++f75frbwP0Nipr+PrTlhw8/KLJOs=@vger.kernel.org X-Gm-Message-State: AOJu0YyMCh0iCRfp7g7elNOB2ZqwdjtsWp1n7PcSvv9WyVd5yxtbwlGY HmV8Qpz3Tj/i6Gk8RPlQ8diGeHsrjJUMu+ti7cYFJrMrKeWJXadCtcFy/Ta9yJIbJ+BZTNmHlMT WMEm//g== X-Received: from pfbho13.prod.google.com ([2002:a05:6a00:880d:b0:7ba:8e68:3140]) (user=seanjc job=prod-delivery.src-stubby-dispatcher) by 2002:a05:6a00:439b:b0:82f:8696:5a75 with SMTP id d2e1a72fcca58-82f8c8bb700mr145981b3a.28.1776379491191; Thu, 16 Apr 2026 15:44:51 -0700 (PDT) Date: Thu, 16 Apr 2026 15:44:49 -0700 In-Reply-To: <20260414-vmscape-bhb-v10-8-efa924abae5f@linux.intel.com> Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20260414-vmscape-bhb-v10-0-efa924abae5f@linux.intel.com> <20260414-vmscape-bhb-v10-8-efa924abae5f@linux.intel.com> Message-ID: Subject: Re: [PATCH v10 08/12] kvm: Define EXPORT_STATIC_CALL_FOR_KVM() From: Sean Christopherson To: Pawan Gupta Cc: x86@kernel.org, Jon Kohler , Nikolay Borisov , "H. Peter Anvin" , Josh Poimboeuf , David Kaplan , Borislav Petkov , Dave Hansen , Peter Zijlstra , Alexei Starovoitov , Daniel Borkmann , Andrii Nakryiko , KP Singh , Jiri Olsa , "David S. Miller" , David Laight , Andy Lutomirski , Thomas Gleixner , Ingo Molnar , David Ahern , Martin KaFai Lau , Eduard Zingerman , Song Liu , Yonghong Song , John Fastabend , Stanislav Fomichev , Hao Luo , Paolo Bonzini , Jonathan Corbet , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, Asit Mallick , Tao Zhang , bpf@vger.kernel.org, netdev@vger.kernel.org, linux-doc@vger.kernel.org Content-Type: text/plain; charset="us-ascii" On Tue, Apr 14, 2026, Pawan Gupta wrote: > EXPORT_SYMBOL_FOR_KVM() exists to export symbols to KVM modules. Static > calls need the same treatment when the core kernel defines a static_call > that KVM needs access to (e.g. from a VM-exit path). > > Define EXPORT_STATIC_CALL_FOR_KVM() as the static_call analogue of > EXPORT_SYMBOL_FOR_KVM(). The same three-way logic applies: > > - KVM_SUB_MODULES defined: export to "kvm," plus all sub-modules > - KVM=m, no sub-modules: export to "kvm" only > - KVM built-in: no export needed (noop) > > As with EXPORT_SYMBOL_FOR_KVM(), allow architectures to override the > definition (e.g. to suppress the export when kvm.ko itself will not be > built despite CONFIG_KVM=m). Add the x86 no-op override in > arch/x86/include/asm/kvm_types.h for that case. > > Signed-off-by: Pawan Gupta > --- > arch/x86/include/asm/kvm_types.h | 1 + > include/linux/kvm_types.h | 13 ++++++++++++- > 2 files changed, 13 insertions(+), 1 deletion(-) > > diff --git a/arch/x86/include/asm/kvm_types.h b/arch/x86/include/asm/kvm_types.h > index d7c704ed1be9..bceeaed2940e 100644 > --- a/arch/x86/include/asm/kvm_types.h > +++ b/arch/x86/include/asm/kvm_types.h > @@ -15,6 +15,7 @@ > * at least one vendor module is enabled. > */ > #define EXPORT_SYMBOL_FOR_KVM(symbol) > +#define EXPORT_STATIC_CALL_FOR_KVM(symbol) > #endif > > #define KVM_ARCH_NR_OBJS_PER_MEMORY_CACHE 40 > diff --git a/include/linux/kvm_types.h b/include/linux/kvm_types.h > index a568d8e6f4e8..c81f4fdba625 100644 > --- a/include/linux/kvm_types.h > +++ b/include/linux/kvm_types.h > @@ -13,6 +13,8 @@ > EXPORT_SYMBOL_FOR_MODULES(symbol, __stringify(KVM_SUB_MODULES)) > #define EXPORT_SYMBOL_FOR_KVM(symbol) \ > EXPORT_SYMBOL_FOR_MODULES(symbol, "kvm," __stringify(KVM_SUB_MODULES)) > +#define EXPORT_STATIC_CALL_FOR_KVM(symbol) \ > + EXPORT_STATIC_CALL_FOR_MODULES(symbol, "kvm," __stringify(KVM_SUB_MODULES)) > #else > #define EXPORT_SYMBOL_FOR_KVM_INTERNAL(symbol) > /* > @@ -27,7 +29,16 @@ > #define EXPORT_SYMBOL_FOR_KVM(symbol) > #endif /* IS_MODULE(CONFIG_KVM) */ > #endif /* EXPORT_SYMBOL_FOR_KVM */ > -#endif > + > +#ifndef EXPORT_STATIC_CALL_FOR_KVM > +#if IS_MODULE(CONFIG_KVM) > +#define EXPORT_STATIC_CALL_FOR_KVM(symbol) EXPORT_STATIC_CALL_FOR_MODULES(symbol, "kvm") > +#else > +#define EXPORT_STATIC_CALL_FOR_KVM(symbol) > +#endif /* IS_MODULE(CONFIG_KVM) */ > +#endif /* EXPORT_STATIC_CALL_FOR_KVM */ > + > +#endif /* KVM_SUB_MODULES */ I think I'd prefer to require EXPORT_SYMBOL_FOR_KVM and EXPORT_STATIC_CALL_FOR_KVM to come as a pair from arch code. I can't think of a scenario where arch code should override one but not the other. The end result is slightly less ugly :-) --- arch/x86/include/asm/kvm_types.h | 1 + include/linux/kvm_types.h | 10 +++++++++- 2 files changed, 10 insertions(+), 1 deletion(-) diff --git a/arch/x86/include/asm/kvm_types.h b/arch/x86/include/asm/kvm_types.h index d7c704ed1be9..bceeaed2940e 100644 --- a/arch/x86/include/asm/kvm_types.h +++ b/arch/x86/include/asm/kvm_types.h @@ -15,6 +15,7 @@ * at least one vendor module is enabled. */ #define EXPORT_SYMBOL_FOR_KVM(symbol) +#define EXPORT_STATIC_CALL_FOR_KVM(symbol) #endif #define KVM_ARCH_NR_OBJS_PER_MEMORY_CACHE 40 diff --git a/include/linux/kvm_types.h b/include/linux/kvm_types.h index a568d8e6f4e8..be602d3f287e 100644 --- a/include/linux/kvm_types.h +++ b/include/linux/kvm_types.h @@ -13,6 +13,8 @@ EXPORT_SYMBOL_FOR_MODULES(symbol, __stringify(KVM_SUB_MODULES)) #define EXPORT_SYMBOL_FOR_KVM(symbol) \ EXPORT_SYMBOL_FOR_MODULES(symbol, "kvm," __stringify(KVM_SUB_MODULES)) +#define EXPORT_STATIC_CALL_FOR_KVM(symbol) \ + EXPORT_STATIC_CALL_FOR_MODULES(symbol, "kvm," __stringify(KVM_SUB_MODULES)) #else #define EXPORT_SYMBOL_FOR_KVM_INTERNAL(symbol) /* @@ -23,11 +25,17 @@ #ifndef EXPORT_SYMBOL_FOR_KVM #if IS_MODULE(CONFIG_KVM) #define EXPORT_SYMBOL_FOR_KVM(symbol) EXPORT_SYMBOL_FOR_MODULES(symbol, "kvm") +#define EXPORT_STATIC_CALL_FOR_KVM(symbol) EXPORT_STATIC_CALL_FOR_MODULES(symbol, "kvm") #else #define EXPORT_SYMBOL_FOR_KVM(symbol) +#define EXPORT_STATIC_CALL_FOR_KVM(symbol) #endif /* IS_MODULE(CONFIG_KVM) */ +#else +#ifndef EXPORT_STATIC_CALL_FOR_KVM +#error Must #define EXPORT_STATIC_CALL_FOR_KVM if #defining EXPORT_SYMBOL_FOR_KVM +#endif #endif /* EXPORT_SYMBOL_FOR_KVM */ -#endif +#endif /* KVM_SUB_MODULES */ #ifndef __ASSEMBLER__ base-commit: 56b7ace84970ff647b095849e80bc36c094760aa --