From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id BD1DE3DCD94; Thu, 2 Apr 2026 10:08:11 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1775124491; cv=none; b=A21dc2ND5JisZXADVGzPOV2QcWolWMUlyWau31iHEQr5UHluXrmL6RNEHGgAdAA3PkZxT1AEA+njBW+Y8QdoDHb5MfYXp2EaOp2U5uFp71J+bP5QbwyCWy6+rvCHVItQz3qqM1ksFrXvjye+5sB3jbM3Xw0Sp1jwT3Fu/fS+PB0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1775124491; c=relaxed/simple; bh=CBS+GA9IR1SPiqF1Zs3xHYu+WRK7gcHd7ay77pLTTSQ=; h=Date:Message-ID:From:To:Cc:Subject:In-Reply-To:References: MIME-Version:Content-Type; b=OqeQ/NtbBuOBxYw3S6UpTRnkzAg8vS2F2377Q9eLRFbWRTNF6jiGryc4Bw9TUJGtiYRrxNgPfS6Cgj8rqo/93tTsJsSPnB5Pv7CvWrNafO7i4bLE6ypUGSGY45AGN2YgoS26UGGM8lblxlaengKz2rWbPfraLyyZcg1VgTXg/cE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=DDQH8THI; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="DDQH8THI" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 424ECC116C6; Thu, 2 Apr 2026 10:08:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1775124491; bh=CBS+GA9IR1SPiqF1Zs3xHYu+WRK7gcHd7ay77pLTTSQ=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=DDQH8THI/aMmucvI6wWnm3KXZEZqhFulzEirJn8NerYH3ZBOf8F3ZLx+/Zh5HprfH 1lXp9wV6RfUmEXC0YFNV+eXoUSik/8mwCkCLFEQTl1g1NDJQh7frn/D8XMqVxN1kH+ 88oI/W+z/9TzPu8/WOnZh71qzNpLYN48XWYjX25ZsQXfFP6lX0eKHSDJS3hM9aDZq4 sxnZG78mVSzAQCxH4UId0BDxjGJMx8wd6LAHcsaDjOrC8jwh5F6N8D1YNJyiW86/zI 7ALJ49MORB0CqhjcdWqA5zEvPOlEdyHmOTgePAqeymOlFIlYZuSt8ku5ONlE9gtz9G BbOaJ3Kz4JzEA== Received: from sofa.misterjones.org ([185.219.108.64] helo=goblin-girl.misterjones.org) by disco-boy.misterjones.org with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.98.2) (envelope-from ) id 1w8Ey8-00000008DGP-3CBA; Thu, 02 Apr 2026 10:08:08 +0000 Date: Thu, 02 Apr 2026 11:08:08 +0100 Message-ID: <86y0j53caf.wl-maz@kernel.org> From: Marc Zyngier To: Steffen Eiden Cc: kvm@vger.kernel.org, kvmarm@lists.linux.dev, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-s390@vger.kernel.org, Andreas Grapentin , Arnd Bergmann , Catalin Marinas , Christian Borntraeger , Claudio Imbrenda , David Hildenbrand , Gautam Gala , Hendrik Brueckner , Janosch Frank , Joey Gouly , Nina Schoetterl-Glausch , Oliver Upton , Paolo Bonzini , Suzuki K Poulose , Ulrich Weigand , Will Deacon , Zenghui Yu Subject: Re: [PATCH v1 07/27] KVM: arm64: Provide arm64 KVM API for non-native architectures In-Reply-To: <20260402042125.3948963-8-seiden@linux.ibm.com> References: <20260402042125.3948963-1-seiden@linux.ibm.com> <20260402042125.3948963-8-seiden@linux.ibm.com> User-Agent: Wanderlust/2.15.9 (Almost Unreal) SEMI-EPG/1.14.7 (Harue) FLIM-LB/1.14.9 (=?UTF-8?B?R29qxY0=?=) APEL-LB/10.8 EasyPG/1.0.0 Emacs/30.1 (aarch64-unknown-linux-gnu) MULE/6.0 (HANACHIRUSATO) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 (generated by SEMI-EPG 1.14.7 - "Harue") Content-Type: text/plain; charset=US-ASCII X-SA-Exim-Connect-IP: 185.219.108.64 X-SA-Exim-Rcpt-To: seiden@linux.ibm.com, kvm@vger.kernel.org, kvmarm@lists.linux.dev, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-s390@vger.kernel.org, Andreas.Grapentin@ibm.com, arnd@arndb.de, catalin.marinas@arm.com, borntraeger@linux.ibm.com, imbrenda@linux.ibm.com, david@kernel.org, ggala@linux.ibm.com, brueckner@linux.ibm.com, frankja@linux.ibm.com, joey.gouly@arm.com, oss@nina.schoetterlglausch.eu, oupton@kernel.org, pbonzini@redhat.com, suzuki.poulose@arm.com, Ulrich.Weigand@de.ibm.com, will@kernel.org, yuzenghui@huawei.com X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on disco-boy.misterjones.org); SAEximRunCond expanded to false On Thu, 02 Apr 2026 05:21:03 +0100, Steffen Eiden wrote: Drive-by comment as I was idly going through this patch. [...] > diff --git a/include/kvm/arm64/kvm_host.h b/include/kvm/arm64/kvm_host.h > new file mode 100644 > index 000000000000..3a434f47497b > --- /dev/null > +++ b/include/kvm/arm64/kvm_host.h [...] > +static inline bool kvm_supports_32bit_el0(void) > +{ > + return false; > +} > + This looks wrong. The original file still has: #define kvm_supports_32bit_el0() \ (system_supports_32bit_el0() && \ !static_branch_unlikely(&arm64_mismatched_32bit_el0)) which should not be tampered with. I guess we are simply lucky that the preprocessor is braindead enough to make this sort of things go unnoticed, but I'd expect this predicate to be directly provided by the s390 code one way or another. Thanks, M. -- Without deviation from the norm, progress is not possible.