From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mx0a-0031df01.pphosted.com (mx0a-0031df01.pphosted.com [205.220.168.131]) (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 91EE5320A1A for ; Thu, 15 Jan 2026 20:14:18 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=205.220.168.131 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768508059; cv=none; b=hkC4mquk/SaOEwcmeztm1SERfmLwjXHmGrXicP5gIa1pt7E8v39m9WK3FDkgJdTA+m27lc3MOKRtXz3gXAgsVbsVf+2BjcUtyQlTXEel6ptxC90GDhUR6E3kni3pc6Ab71zfBBjKaquhGUScZaF75IAAETDuCjODMuysdDJQ8yU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768508059; c=relaxed/simple; bh=3m1JDKUE6dCwtGw1I+GY5YI4+Ska1S2i/RrQAxVN7+4=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=YnLun4p16CO87Wyv4m/iBWyCc5gZ/3rZ4HDojo5GVU1v7H5O1RqA7he+32xebrp5+aXAoDrrKauCG6GQJEpZhuK68L0T6V6OlmjWwGgU66PbPTWRUF0vxy+1f5AzC7ii6CswP83qojWWaF4CkSs58gpzLpySY0pSdGw+beRYj8o= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=oss.qualcomm.com; spf=pass smtp.mailfrom=oss.qualcomm.com; dkim=pass (2048-bit key) header.d=qualcomm.com header.i=@qualcomm.com header.b=JD+4LhsY; dkim=pass (2048-bit key) header.d=oss.qualcomm.com header.i=@oss.qualcomm.com header.b=coy7tj/4; arc=none smtp.client-ip=205.220.168.131 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=oss.qualcomm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=oss.qualcomm.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=qualcomm.com header.i=@qualcomm.com header.b="JD+4LhsY"; dkim=pass (2048-bit key) header.d=oss.qualcomm.com header.i=@oss.qualcomm.com header.b="coy7tj/4" Received: from pps.filterd (m0279864.ppops.net [127.0.0.1]) by mx0a-0031df01.pphosted.com (8.18.1.11/8.18.1.11) with ESMTP id 60FFY7qN347705 for ; Thu, 15 Jan 2026 20:14:18 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=qualcomm.com; h= cc:content-transfer-encoding:content-type:date:from:in-reply-to :message-id:mime-version:references:subject:to; s=qcppdkim1; bh= LKwHoFo1Q1ynCePJR7x2gLgJu/69dXmFcv2uVKcHJ+g=; b=JD+4LhsYsd/zjfgQ 5xcwxy8GIOeREQp1A/K/Tlmc1lp/UuMnIWpB4Xzm6lCiSFbF2vJURh+n3gXpYrQd NKHjmf23+KlBuKa4zJvsme4zlCh4kGVqG26SVV+ZETAKkOmOGrWbMW7ASbGHbJiO Bx/ch6a1e6WkHQM+uu4jL7KG0hFitk6forjT/sQVYjtL3ju9f7LWpn8s5ITmBOjW E6xnjcjtuwh57wYT3aPbQzLHIoWcpxgdvbh4ruRK9vg13M5YM2N+902KHZ98tcKJ sKiRMzFzydMX2hMbSvALvkA+ax0QFdm5xSCqIqLGXdtzWYl1bMAqXomlw5EG+Xe/ p8ayZQ== Received: from mail-dl1-f72.google.com (mail-dl1-f72.google.com [74.125.82.72]) by mx0a-0031df01.pphosted.com (PPS) with ESMTPS id 4bpy07spa9-1 (version=TLSv1.3 cipher=TLS_AES_128_GCM_SHA256 bits=128 verify=NOT) for ; Thu, 15 Jan 2026 20:14:17 +0000 (GMT) Received: by mail-dl1-f72.google.com with SMTP id a92af1059eb24-11b9786fb51so8257444c88.1 for ; Thu, 15 Jan 2026 12:14:17 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oss.qualcomm.com; s=google; t=1768508057; x=1769112857; darn=vger.kernel.org; h=content-transfer-encoding:in-reply-to:from:content-language :references:cc:to:subject:user-agent:mime-version:date:message-id :from:to:cc:subject:date:message-id:reply-to; bh=LKwHoFo1Q1ynCePJR7x2gLgJu/69dXmFcv2uVKcHJ+g=; b=coy7tj/4SHtZ9CnIff0BkkOJ36HuB9Ap2m6NpfMbkhLM8NW1TE4IJ/Rri3DNZZzLzS dBfrTiP1q8Q0b0mmLU/FZ18WNkoc7YFo7k8cbM81u7zYmIC2o/4ewhppGzwvvhmp+/J/ sFzHo5b4EpoD7nBkMKhcV3t7Ji/dCsCrTGRvu0n31Gf7zH6M/aholxQL9kY3zQwUC4tQ EH3xzYgsxRfIKOtCKC298oqJnZDa9QdM2q82enlnItZwnGje0Ev5ecRgn51XddcoXHXU Mq4vhqzdQeNK1ZkxVwIsfqgCWkpvvQ08WVgxZv32RAPFJJazuCbRnCnV93wK1S3N7da6 QjVw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1768508057; x=1769112857; h=content-transfer-encoding:in-reply-to:from:content-language :references:cc:to:subject:user-agent:mime-version:date:message-id :x-gm-gg:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=LKwHoFo1Q1ynCePJR7x2gLgJu/69dXmFcv2uVKcHJ+g=; b=AX75XTgicrZ+BaYaa2aQktpr15pTAp+mIXcM39i8KYU3FPgurDkEyF63cY5dwd38G9 JYRy7SNNL0AiXpmDvV4vXw9tue55eQBNDDgtbQ7BBoHtKgVawwfASHBvyiTSCNRw3vX5 VO9P1NMZnhThCcmkuZNvSBO5M/Gz+1Lr65jayX8cvsMOtWh6cODb+ffZ7OmI8sWkPQ8C 8wro54X1luGIglWDVLNPZyG2UTisCr+CZcPC0OemYB9F6JskXKSp9QJ8Lks+1EbdTZFJ ppS/1zj8yHegKfIR/NSFevDP8jfc7JVufj1iqOPSoW0HaImkLwDEEb2X74iTXt37oWqk mbWA== X-Forwarded-Encrypted: i=1; AJvYcCXJH5uzO6mhCiJcTDet/s1jgURv+rJ1oVA1TKw76J47P35bQEYlXDPS/m9m0NxkcNPE+DXESHz8Emkww/4=@vger.kernel.org X-Gm-Message-State: AOJu0YweBIe3LKkvCVcAIwnhcR7CJA1ix+1fYanE2WvnRBeCgFYX1c2G bOJu2JVPJM+f+ON0LIQ9N1e0blwLKkvNi2wcavYvjLhvGeJpjsloKr6O2dVnGh4fzLGKRpnF7sX ZN8Sw3Xpjdn84hyvF002Uz59iRnF57LmdvrpqS9B07sUjuRSJpr9mn7XQFgCcOqWa4tY= X-Gm-Gg: AY/fxX5Qi+j/5zz5ybPAudDhXZtJOFGO7qVd1COCJaLaTYahvPSofiH5y7gWFmgFHqw K2JXsU113jmjqKue2OrgfJSwMYVEEufGsxinHAiz0gDHrDDXzCtr9rOlFEq+U06/QGcXyyYD2Lk YjyG17a/hulebRQKEM6jlNNVi5POBt/+4KGIea1Iule1b8MPFsaDCjYD7dK/YEoeB3fF70f1aO7 ucK8ZftQGWhLUiu4sID1CaTgn+CEHy6C8C6fsQzk7uauqvjcWGBuC5FUb+GyZpKEprSfIMRKDJ5 ZZnBApYdkGeNF+UDTmRtTg1TFo42N3mnZazVSGwc3yvZZeSprt11oXgNvjku4WzaBhSrnRXK7VU ClFqztYMmx9yraHtGU7c81N1WGEBYkqJwmsboEwhVM+48+aCun0z0ZhM5Quyk X-Received: by 2002:a05:7022:628f:b0:123:3356:7abb with SMTP id a92af1059eb24-1244a7a1f4emr1005351c88.46.1768508056839; Thu, 15 Jan 2026 12:14:16 -0800 (PST) X-Received: by 2002:a05:7022:628f:b0:123:3356:7abb with SMTP id a92af1059eb24-1244a7a1f4emr1005320c88.46.1768508056292; Thu, 15 Jan 2026 12:14:16 -0800 (PST) Received: from [10.73.212.179] (pat_11.qualcomm.com. [192.35.156.11]) by smtp.gmail.com with ESMTPSA id a92af1059eb24-1244aefaf0asm405764c88.9.2026.01.15.12.14.15 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 15 Jan 2026 12:14:15 -0800 (PST) Message-ID: <53760601-dfd7-4536-9cd5-9241800c6c73@oss.qualcomm.com> Date: Thu, 15 Jan 2026 12:14:15 -0800 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH] firmware: smccc: default ARM_SMCCC_SOC_ID to disabled To: Dmitry Baryshkov Cc: Mark Rutland , Lorenzo Pieralisi , Sudeep Holla , linux-arm-msm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, trilok.soni@oss.qualcomm.com References: <20260112-disable_smccc_soc_id-v1-1-a5bee24befb4@oss.qualcomm.com> <7ruiccdm7q5fg2pixmszr3fqvclvymdlkv4x4xbavkaeczrxgc@5l6usxqfi5fe> <619f20eb-77e4-4250-ba5e-78db741ebbef@oss.qualcomm.com> <7jhqea42453esyx4sv3okowy7jrdcrd4sxjpm4t2snsyi3nfl4@ieja4c4q3jj5> Content-Language: en-US From: Satya Durga Srinivasu Prabhala In-Reply-To: <7jhqea42453esyx4sv3okowy7jrdcrd4sxjpm4t2snsyi3nfl4@ieja4c4q3jj5> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-Proofpoint-GUID: 29xnOp_QmxzZ5zk3eR8_h8suPXrIZJzH X-Authority-Analysis: v=2.4 cv=fMw0HJae c=1 sm=1 tr=0 ts=69694a99 cx=c_pps a=bS7HVuBVfinNPG3f6cIo3Q==:117 a=ZdW6uxA9NKXbfdqeeS2OGA==:17 a=IkcTkHD0fZMA:10 a=vUbySO9Y5rIA:10 a=s4-Qcg_JpJYA:10 a=VkNPw1HP01LnGYTKEx00:22 a=VwQbUJbxAAAA:8 a=EUspDBNiAAAA:8 a=DTRC8DjRNAS07NXFP4gA:9 a=3ZKOabzyN94A:10 a=QEXdDO2ut3YA:10 a=vBUdepa8ALXHeOFLBtFW:22 X-Proofpoint-ORIG-GUID: 29xnOp_QmxzZ5zk3eR8_h8suPXrIZJzH X-Proofpoint-Spam-Details-Enc: AW1haW4tMjYwMTE1MDE1OCBTYWx0ZWRfX50G5qMVrT2UB h/SuXHH090Mojcw6lGObSgPLh86DB0lq4sN5irNPkzWjmBntYkX5DZgpsmLkkWKHPN7wiXfVNuf z5wyKOgXqShWZ4xV6uclLhXOnXZyk1qIkc8kWiHsSas/3TVU+CIUMjQtw2b+Qtj4CyqfECFPHTY EnWyxpP8ZLnGVTuKNntTus07AEy2bcT33Dt52Xb7WcwdMV4mnpSGxD/vPOyvTVLxrga+wvzcZ4t mM0X8aoUiR+wPbFV/llXaj21Ft1FY2W8w9LhRG/goV/aS/6/RK4g8nQjXazoy8cuWrbDzEiBoM4 Iywok5edAn3glg2yWvU+7BNsXyCxVlMXn9j61Mt90mtYUcBqMLd0aP2YoT4G4hHnMUUO0YNtabE b3arkNuPWYB89+MgeJbl+wuzDr5GqjkfC3xtrdkbS9kCk+AORq/hJGNmBG3OFHAJuGR0P73NT9x tee47HZOHsAqi0PhETg== X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1121,Hydra:6.1.9,FMLib:17.12.100.49 definitions=2026-01-15_06,2026-01-15_01,2025-10-01_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 clxscore=1015 impostorscore=0 malwarescore=0 adultscore=0 lowpriorityscore=0 phishscore=0 priorityscore=1501 suspectscore=0 bulkscore=0 spamscore=0 classifier=typeunknown authscore=0 authtc= authcc= route=outbound adjust=0 reason=mlx scancount=1 engine=8.22.0-2512120000 definitions=main-2601150158 On 1/14/2026 11:37 AM, Dmitry Baryshkov wrote: > On Wed, Jan 14, 2026 at 10:04:21AM -0800, Satya Durga Srinivasu Prabhala wrote: >> Hello Dmitry, >> >> On 1/13/2026 3:25 AM, Dmitry Baryshkov wrote: >>> On Mon, Jan 12, 2026 at 10:24:06PM -0800, Satya Durga Srinivasu Prabhala wrote: >>>> The ARM SMCCC SoC ID driver is currently enabled by default and publishes >>>> SMCCC-provided SoC identification into /sys/bus/soc/devices/socX/*. >>>> >>>> On platforms where a vendor SoC driver already exposes widely-consumed >>>> attributes (e.g. Qualcomm socinfo [1]), enabling the SMCCC driver changes >>>> the format of /sys/devices/soc0/soc_id (e.g. "jep106:XXYY:ZZZZ" instead >>>> of a vendor logical ID like "519") and breaks existing userspace consumers. >>>> >>>> Flip the default of CONFIG_ARM_SMCCC_SOC_ID from y to n. Platforms that >>>> prefer SMCCC over a vendor driver can explicitly enable it. >>> NAK, the userspace should not depend on the exact kernel configuration. >>> Consider working with distribution kernels, which would enable this >>> driver anyway. >> As I mentioned in the other replies, vendor interface exists before the >> standard >> interface and user space heavily relies on soc0 already. If not disabling >> the >> SMCCC SOC ID by default. I believe, we should  at-least have a way to make >> sure vendors can disable SMCCC SOC ID by some means or have vendor >> interface takes precedence. > Please correct me if I'm wrong, what do you observe? SMCCC device on > soc0 and qcom_socinfo at soc1? Yes, that is absolutely correct, Dmitry. > In such a case the ABI file, Documentation/ABI/testing/sysfs-devices-soc clearly > defines that there might be several different SoC devices (identified by > different drivers, etc). If the userspace depends on qcom_socinfo device > being soc0, then the userspace is broken. Yes, there is no question about that. User space had certain assumption on SoC Devices. The point to note is, user space had those assumptions based on vendor interfaces which existed from long time. > Last, but not least, the soc_id format is documented in the ABI > document. It is clearly allowed to have jep106 format in the soc_id. So, > I think, you have two options: disable SMCCC 1.2+ in the firmware or > adapt the userspace. You can't control e.g. the kernel that will be > running on your platform (it very well can be a standard distro kernel > from Debian, Ubuntu or Fedora, which obviously will have that driver > enabled). IMHO, vendors at-least should have a way to choose what interface needs to be exposed to user space (vendor vs SMCCC). >> Best, >> Satya >>>> This avoids unexpected format changes and keeps the generic SoC sysfs >>>> stable on systems that rely on vendor-specific identification. >>>> >>>> [1] >>>> Link: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/drivers/soc/qcom/socinfo.c >>>> >>>> Signed-off-by: Satya Durga Srinivasu Prabhala >>>> --- >>>> drivers/firmware/smccc/Kconfig | 5 ++++- >>>> 1 file changed, 4 insertions(+), 1 deletion(-) >>>>