From nobody Mon Feb 9 13:39:24 2026 Received: from galois.linutronix.de (Galois.linutronix.de [193.142.43.55]) (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 A82C52DF12F; Thu, 15 Jan 2026 07:36:00 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=193.142.43.55 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768462562; cv=none; b=lZxd75o/IP0nbwzhzKVXv72eqi0HgyKt5NcEIaFfhN3CWa3kakx+C0cmckNnr3Ljtct1het16nUeWaZXpkIIf8JZZ9XuacTN0LnKUOfPEchmuJepFeoE7ewRESyNLclsQIEqvTjl7JbO/Yzni+32S42VqSiMSXGsmGrru6iLpCU= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768462562; c=relaxed/simple; bh=gQlXs4q19xMLM8Wc0CIfifmCM1u8xor1ADjg8gkJ/Mk=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=ubR848okkoKyEVp85wIwngOsrX3ITXb7ULOnOfUiVllEihF8l3LdmA/MuKvw3xxagozyr9XPmPtzgCix0DIHzwJvE3eeEnhbLD2GbLcSfATj8gYipkn3dOhxpQFI1Oc79Pd6SSZsLiS9ILSTyOCdn6hJlMbdweITlDS2Ir87xOA= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linutronix.de; spf=pass smtp.mailfrom=linutronix.de; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b=rON4D/uq; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b=IzWc++SX; arc=none smtp.client-ip=193.142.43.55 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linutronix.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linutronix.de Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="rON4D/uq"; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="IzWc++SX" From: =?utf-8?q?Thomas_Wei=C3=9Fschuh?= DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1768462559; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=SuFTyZHzQGk2QqDXdX5OISfkQ27KHUy/T6UHqgFncd4=; b=rON4D/uqufLb7MBQX7MP9+157kpnGJfYzYe693nFE0CfGwYJqMsg6c1qiF9tj9lYct82+1 Q5WEarD5jWgy0/rsFEA3vAZlK6CpgNWfTRvvMDVPSByFuOmkp5REJlXa4U27nqcgt7/IA4 JEUi6zCP8Nl1P6tzcdg9nBo0m6Dxh826ha2VOdmKkLhET9Taz5PvNvZK7puuwD734Z2bgL SyLkE0kiMwKUagONYKFDX0I34gQUhl+IEKvH2mejMLgGEOY5MybB7vmTUTFEGm9DRqrQUY oAD9MTXEqR3lE/90PtkfCDKYDMyh2Q+EaoAw6bS5vEPTK/JaweMqpxIMCN8XeA== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1768462559; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=SuFTyZHzQGk2QqDXdX5OISfkQ27KHUy/T6UHqgFncd4=; b=IzWc++SXQVXqyTI6SLJupr/3UgPlHEDDdzHpCHUjM0XhXA1tkcyxgTJvlbqw1lB0XNH6aW 18FPsH7CsUWBP/Dg== Date: Thu, 15 Jan 2026 08:35:44 +0100 Subject: [PATCH 1/2] hyper-v: Mark inner union in hv_kvp_exchg_msg_value as packed Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Message-Id: <20260115-kbuild-alignment-vbox-v1-1-076aed1623ff@linutronix.de> References: <20260115-kbuild-alignment-vbox-v1-0-076aed1623ff@linutronix.de> In-Reply-To: <20260115-kbuild-alignment-vbox-v1-0-076aed1623ff@linutronix.de> To: "K. Y. Srinivasan" , Haiyang Zhang , Wei Liu , Dexuan Cui , Long Li , Nathan Chancellor , Nick Desaulniers , Bill Wendling , Justin Stitt , Hans de Goede , Arnd Bergmann , Greg Kroah-Hartman Cc: linux-hyperv@vger.kernel.org, linux-kernel@vger.kernel.org, llvm@lists.linux.dev, =?utf-8?q?Thomas_Wei=C3=9Fschuh?= , kernel test robot X-Developer-Signature: v=1; a=ed25519-sha256; t=1768462556; l=1716; i=thomas.weissschuh@linutronix.de; s=20240209; h=from:subject:message-id; bh=gQlXs4q19xMLM8Wc0CIfifmCM1u8xor1ADjg8gkJ/Mk=; b=SIoPm7+F/yGCU03lpF4m0kxUTlX7Bb+SOZO7DxAscLIoTmLE0klPAVbhDlHusnht1D/WG98ND q/0fZdrq4gnDQSjppUjJXcfn92bIN6mKVkogvcWF+E+xoranVUtvIPg X-Developer-Key: i=thomas.weissschuh@linutronix.de; a=ed25519; pk=pfvxvpFUDJV2h2nY0FidLUml22uGLSjByFbM6aqQQws= The unpacked union within a packed struct generates alignment warnings on clang for 32-bit ARM: ./usr/include/linux/hyperv.h:361:2: error: field within 'struct hv_kvp_exc= hg_msg_value' is less aligned than 'union hv_kvp_exchg_msg_value::(anonymous at ./usr/i= nclude/linux/hyperv.h:361:2)' and is usually due to 'struct hv_kvp_exchg_msg_value' being packed, which can lead to unaligned accesses [-Werror,-Wunaligned-access] 361 | union { | ^ With the recent changes to compile-test the UAPI headers in more cases, this warning in combination with CONFIG_WERROR breaks the build. Fix the warning. Reported-by: kernel test robot Closes: https://lore.kernel.org/oe-kbuild-all/202512140314.DzDxpIVn-lkp@int= el.com/ Reported-by: Nathan Chancellor Closes: https://lore.kernel.org/linux-kbuild/20260110-uapi-test-disable-hea= ders-arm-clang-unaligned-access-v1-1-b7b0fa541daa@kernel.org/ Suggested-by: Arnd Bergmann Link: https://lore.kernel.org/linux-kbuild/29b2e736-d462-45b7-a0a9-85f8d8a3= de56@app.fastmail.com/ Signed-off-by: Thomas Wei=C3=9Fschuh Acked-by: Greg Kroah-Hartman Acked-by: Wei Liu (Microsoft) Reviewed-by: Nicolas Schier Tested-by: Nicolas Schier --- include/uapi/linux/hyperv.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/include/uapi/linux/hyperv.h b/include/uapi/linux/hyperv.h index aaa502a7bff4..1749b35ab2c2 100644 --- a/include/uapi/linux/hyperv.h +++ b/include/uapi/linux/hyperv.h @@ -362,7 +362,7 @@ struct hv_kvp_exchg_msg_value { __u8 value[HV_KVP_EXCHANGE_MAX_VALUE_SIZE]; __u32 value_u32; __u64 value_u64; - }; + } __attribute__((packed)); } __attribute__((packed)); =20 struct hv_kvp_msg_enumerate { --=20 2.52.0 From nobody Mon Feb 9 13:39:24 2026 Received: from galois.linutronix.de (Galois.linutronix.de [193.142.43.55]) (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 64B1B31578F; Thu, 15 Jan 2026 07:36:01 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=193.142.43.55 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768462564; cv=none; b=sBkpTn/NgqaBbUiIX1e0EQAgqGsLQmhyhkCdzKGEI7ux5KHUFS87GPZ62HkJZKVLwcVmghntgrPsaBPOm5/4mlH8yBO5GfimBxtchI+tii1bawSCP3SQPpPjTxUfWbVbh2dhHcZZpdG7Zy7cK6Db/Od8W7I7oGRRCSLXySxlL3s= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768462564; c=relaxed/simple; bh=Uf4LnRBelGVyDvh256L7550y1T4VRuzh8TwYPxjXxWE=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=MNHyojIbtmwKxuCiuT/sK9UaxxvcPBRNUxtfd9ACYU/1nfaOLRaG7IfO81RDYViMLU9yvXtfzCP5Tf3cmIW6H944bDR4s9yR3YI5M1QPuw0kYO/+HoZ0lnneVpIynKN1h93UM5O50/Vcchr84q15hipoiv82I7FPkJV3No0zSuU= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linutronix.de; spf=pass smtp.mailfrom=linutronix.de; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b=rsiFZqv3; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b=LESULiCJ; arc=none smtp.client-ip=193.142.43.55 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linutronix.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linutronix.de Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="rsiFZqv3"; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="LESULiCJ" From: =?utf-8?q?Thomas_Wei=C3=9Fschuh?= DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1768462559; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=ZmJfbgsi5ZQog2/tvaxio1e94jEe7ryoDan67NooQFU=; b=rsiFZqv34iH7cqVI5zlA0ZsX5brXxKxkZv5NHg/roCNR4COcMx0rwulyevzYMS3oJqEaml 62pELoOvg1yExFEYAmBKLXXNh0RO5/oJxdlNGUZCzQav+UebPfmwEs4042Ptlve8M9xtpC 2hLBWmKfZDY17vRCwA5m0RIIgsKINAzUi9gjs93al1BbrBFgatiCisYnkyvD5FMpCZc6iE Z8hAGpsi/9h+rjLg6cIxLVO3e/L83my5waE/0PmuUiHStxuHdYNDMH37XA8C2Gdb6i8dFm CqoQpkA5JRoP/duCRSmMTyBaIxsRKKMW+7m/qwz2M7idw5enJp8p44qFK2dhnQ== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1768462559; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=ZmJfbgsi5ZQog2/tvaxio1e94jEe7ryoDan67NooQFU=; b=LESULiCJlpZ5X+Z6LNcgrw/nSUW6xEXYvqeNuo2AZv1t3DZBwpuO/6ubTvnHYKsvVRvxXb AVS3AzpfXTrYXJBQ== Date: Thu, 15 Jan 2026 08:35:45 +0100 Subject: [PATCH 2/2] virt: vbox: uapi: Mark inner unions in packed structs as packed Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Message-Id: <20260115-kbuild-alignment-vbox-v1-2-076aed1623ff@linutronix.de> References: <20260115-kbuild-alignment-vbox-v1-0-076aed1623ff@linutronix.de> In-Reply-To: <20260115-kbuild-alignment-vbox-v1-0-076aed1623ff@linutronix.de> To: "K. Y. Srinivasan" , Haiyang Zhang , Wei Liu , Dexuan Cui , Long Li , Nathan Chancellor , Nick Desaulniers , Bill Wendling , Justin Stitt , Hans de Goede , Arnd Bergmann , Greg Kroah-Hartman Cc: linux-hyperv@vger.kernel.org, linux-kernel@vger.kernel.org, llvm@lists.linux.dev, =?utf-8?q?Thomas_Wei=C3=9Fschuh?= , kernel test robot X-Developer-Signature: v=1; a=ed25519-sha256; t=1768462556; l=2576; i=thomas.weissschuh@linutronix.de; s=20240209; h=from:subject:message-id; bh=Uf4LnRBelGVyDvh256L7550y1T4VRuzh8TwYPxjXxWE=; b=lNuIsxK9kyAW4nia9it1+N+6Jv4CmihW70V0JoQD+pak81IehyJF6TLWmzvPrCduaYm3I7hUX bfz/a8mBwO5BHP/sqVrHQoVqJb7DHhSYlMsihjoW/4SehIUBtuhzPPT X-Developer-Key: i=thomas.weissschuh@linutronix.de; a=ed25519; pk=pfvxvpFUDJV2h2nY0FidLUml22uGLSjByFbM6aqQQws= The unpacked unions within a packed struct generates alignment warnings on clang for 32-bit ARM: ./usr/include/linux/vbox_vmmdev_types.h:239:4: error: field u within 'struc= t vmmdev_hgcm_function_parameter32' is less aligned than 'union (unnamed union at ./usr/include/linux/vbox_vm= mdev_types.h:223:2)' and is usually due to 'struct vmmdev_hgcm_function_parameter32' being pac= ked, which can lead to unaligned accesses [-Werror,-Wunaligned-access] 239 | } u; | ^ ./usr/include/linux/vbox_vmmdev_types.h:254:6: error: field u within 'struct vmmdev_hgcm_function_parameter64::(anonymous union)::(unnamed at = ./usr/include/linux/vbox_vmmdev_types.h:249:3)' is less aligned than 'union (unnamed union at ./usr/include/linux/vbox_vm= mdev_types.h:251:4)' and is usually due to 'struct vmmdev_hgcm_function_parameter64::(anonymous union)::(unnamed at = ./usr/include/linux/vbox_vmmdev_types.h:249:3)' being packed, which can lead to unaligned accesses [-Werror,-Wunaligned-a= ccess] With the recent changes to compile-test the UAPI headers in more cases, these warning in combination with CONFIG_WERROR breaks the build. Fix the warnings. Reported-by: kernel test robot Closes: https://lore.kernel.org/oe-kbuild-all/202512140314.DzDxpIVn-lkp@int= el.com/ Reported-by: Nathan Chancellor Closes: https://lore.kernel.org/linux-kbuild/20260110-uapi-test-disable-hea= ders-arm-clang-unaligned-access-v1-1-b7b0fa541daa@kernel.org/ Suggested-by: Arnd Bergmann Link: https://lore.kernel.org/linux-kbuild/29b2e736-d462-45b7-a0a9-85f8d8a3= de56@app.fastmail.com/ Signed-off-by: Thomas Wei=C3=9Fschuh Acked-by: Greg Kroah-Hartman Reviewed-by: Nicolas Schier Tested-by: Nicolas Schier --- include/uapi/linux/vbox_vmmdev_types.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/include/uapi/linux/vbox_vmmdev_types.h b/include/uapi/linux/vb= ox_vmmdev_types.h index 6073858d52a2..11f3627c3729 100644 --- a/include/uapi/linux/vbox_vmmdev_types.h +++ b/include/uapi/linux/vbox_vmmdev_types.h @@ -236,7 +236,7 @@ struct vmmdev_hgcm_function_parameter32 { /** Relative to the request header. */ __u32 offset; } page_list; - } u; + } __packed u; } __packed; VMMDEV_ASSERT_SIZE(vmmdev_hgcm_function_parameter32, 4 + 8); =20 @@ -251,7 +251,7 @@ struct vmmdev_hgcm_function_parameter64 { union { __u64 phys_addr; __u64 linear_addr; - } u; + } __packed u; } __packed pointer; struct { /** Size of the buffer described by the page list. */ --=20 2.52.0