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 93D8835898; Wed, 6 Aug 2025 22:26:03 +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=1754519163; cv=none; b=OQ8HwK9JdAADoV69Nje8XTJacFXpclfAEaMj8Ct19OcGTZiFD+NPznK4xqV4GrhldKjMh7AsX8uzkdlZN+osgpNPNakgYDUHzjem96MqLKDXSPreFDo6NmIYInvKQgWtCNM4K55pmqtuadEwa5DdITO1yRM4p/rgbGIJX0VmY8M= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1754519163; c=relaxed/simple; bh=wSP/FnjATYBkD9tjSijm87GKcLGQ9Dv8hJCzfo90h/s=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=BbbPQJwcc2cAWRYMqvaOFjhP1PlLsQCwMv2f7xABJE/7t4C4cIOF4dU/Y2p8nje5lXcz0oFSafZZLBEngAix3h1QeX7ljfkucagZ5SFkhmpOulxjM4LrSS2BMTevY4ZqOK/Y1oGz265ljcdwzqyGtNUBozayk6JqENMTq3BgRJw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=iZVZtpHc; 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="iZVZtpHc" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 487F9C4CEE7; Wed, 6 Aug 2025 22:26:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1754519163; bh=wSP/FnjATYBkD9tjSijm87GKcLGQ9Dv8hJCzfo90h/s=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=iZVZtpHcJ84kPEusQRbGh0yw0RjPpg0xx99EEBSWIBT7fatVExcSR13RCFr0P/Am9 f2rvIpIy9szjA5QOgilFY47ledEhI6DZBUnBeVsHIa6foNSKny7oPvL/byTHW/fhTr UnwXixzezWxz5XRhtEWzuk1Ypp9tdH5bYTc9opJToSJ/fx2bbRqIebIzkKbNENvG1W NJsvHnXcqdajLfRfpjWXrBzmSSTm5hIwNg4NCzwwUmkZyCA8zHEis15KZ4E///gMeC XEO+0WBvsRRHw7PazG7Z22ryiE+ERSdb085I8LV78NiNdQmClZ/9uAxCOAHac92DHo 97Th+tup2Yegw== Date: Wed, 6 Aug 2025 15:25:57 -0700 From: Nathan Chancellor To: Justin Stitt Cc: Marc Zyngier , James Morse , Alexandru Elisei , Suzuki K Poulose , Oliver Upton , Catalin Marinas , Will Deacon , Tom Rix , linux-arm-kernel@lists.infradead.org, kvmarm@lists.linux.dev, linux-kernel@vger.kernel.org, llvm@lists.linux.dev, stable@vger.kernel.org Subject: Re: [PATCH 6.1.y] KVM: arm64: sys_regs: disable -Wuninitialized-const-pointer warning Message-ID: <20250806222557.GA1654483@ax162> References: <20250728-stable-disable-unit-ptr-warn-v1-1-958be9b66520@google.com> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20250728-stable-disable-unit-ptr-warn-v1-1-958be9b66520@google.com> On Mon, Jul 28, 2025 at 02:07:36PM -0700, Justin Stitt wrote: > A new warning in Clang 22 [1] complains that @clidr passed to > get_clidr_el1() is an uninitialized const pointer. get_clidr_el1() > doesn't really care since it casts away the const-ness anyways -- it is > a false positive. > > | ../arch/arm64/kvm/sys_regs.c:2978:23: warning: variable 'clidr' is uninitialized when passed as a const pointer argument here [-Wuninitialized-const-pointer] > | 2978 | get_clidr_el1(NULL, &clidr); /* Ugly... */ > | | ^~~~~ > > Disable this warning for sys_regs.o with an iron fist as it doesn't make > sense to waste maintainer's time or potentially break builds by > backporting large changelists from 6.2+. > > This patch isn't needed for anything past 6.1 as this code section was > reworked in Commit 7af0c2534f4c ("KVM: arm64: Normalize cache > configuration"). > > Cc: stable@vger.kernel.org > Fixes: 7c8c5e6a9101e ("arm64: KVM: system register handling") > Link: https://github.com/llvm/llvm-project/commit/00dacf8c22f065cb52efb14cd091d441f19b319e [1] > Signed-off-by: Justin Stitt > --- Yes, I think this is an appropriate way to address this for stable. Reviewed-by: Nathan Chancellor > --- > arch/arm64/kvm/Makefile | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/arch/arm64/kvm/Makefile b/arch/arm64/kvm/Makefile > index 5e33c2d4645a..5fdb5331bfad 100644 > --- a/arch/arm64/kvm/Makefile > +++ b/arch/arm64/kvm/Makefile > @@ -24,6 +24,9 @@ kvm-y += arm.o mmu.o mmio.o psci.o hypercalls.o pvtime.o \ > > kvm-$(CONFIG_HW_PERF_EVENTS) += pmu-emul.o pmu.o > > +# Work around a false positive Clang 22 -Wuninitialized-const-pointer warning > +CFLAGS_sys_regs.o := $(call cc-disable-warning, uninitialized-const-pointer) > + > always-y := hyp_constants.h hyp-constants.s > > define rule_gen_hyp_constants > > --- > base-commit: 830b3c68c1fb1e9176028d02ef86f3cf76aa2476 > change-id: 20250728-stable-disable-unit-ptr-warn-281fee82539c > > Best regards, > -- > Justin Stitt >