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charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-Authority-Analysis: v=2.4 cv=BOW+bVQG c=1 sm=1 tr=0 ts=6967c951 cx=c_pps a=Uww141gWH0fZj/3QKPojxA==:117 a=Q5rFrUx7DTp4enn/YD2GRQ==:17 a=IkcTkHD0fZMA:10 a=vUbySO9Y5rIA:10 a=s4-Qcg_JpJYA:10 a=VkNPw1HP01LnGYTKEx00:22 a=VwQbUJbxAAAA:8 a=g4MP2Je7yr20VYQK4wsA:9 a=3ZKOabzyN94A:10 a=QEXdDO2ut3YA:10 a=PxkB5W3o20Ba91AHUih5:22 X-Proofpoint-ORIG-GUID: dn3jZ0QdOqpPPPbjYB9K6po_G_aDe1BE X-Proofpoint-Spam-Details-Enc: AW1haW4tMjYwMTE0MDE0MSBTYWx0ZWRfXwIUhCBUuPPZ3 8p/zrWGPkYpzai7cByYeK3pADIMiWv1MDcpiAs4jZ5OFOBO61e75rAILFCXL8kW/WBGbIqwaNbe C4v3nyKWMplUaLYlXpQo7jM31t9T3Y+lLtvRRJWCZ9ajr9piJHtQTZipsx5+Z/8A7go7uojEVMR GKGCA3zG+8ZHNTNx1817Qcast2gqbckx2/7VLY5rTXQFt9fiDR58ZRAr7w8jw89TE4+BcoOSMj0 LhYW9v+DF1/AAJc1xDv4OYE89vo8NSPR96lSqImxYjXqHbmvu8MhgJ8PZJiS1sOe2b9d0TaMCkO 7+ifch3Z/zQCg4Tl6wTO/I/0aR7WrEKQQVHRwzkMTNgG7P/gQ22sw2bdXlnHW/On2NpJhtgfW1k grRshKKFK55rMV1xP4LcQTpxvf7xDMGdiKSXhWhUha7l6yM6/gHxOC+pAofV99x6aGcMUDf4CT0 048eJG8k/3DdDBbORCw== X-Proofpoint-GUID: dn3jZ0QdOqpPPPbjYB9K6po_G_aDe1BE 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=2026-01-14_05,2026-01-14_01,2025-10-01_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 suspectscore=0 spamscore=0 priorityscore=1501 malwarescore=0 clxscore=1015 adultscore=0 lowpriorityscore=0 phishscore=0 impostorscore=0 bulkscore=0 classifier=typeunknown authscore=0 authtc= authcc= route=outbound adjust=0 reason=mlx scancount=1 engine=8.22.0-2512120000 definitions=main-2601140141 Hello Sudeep, On 1/13/2026 4:29 AM, Sudeep Holla 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. >> > Instead of relying on a vendor-specific SoC driver, we should consider > disabling it and using the OS-agnostic SoC information interface provided by > the firmware. Would like to add some history here. Vendor interface existed [1] even before SMCCC SMC ID was introduced [2]. And there are several user space entities which uses the soc0 interface already. > The presence of this interface strongly suggests that the > firmware is designed to support multiple operating systems or software stacks > that already depend on it. That is correct. We started seeing the issue with user space when our firmware started implementing support for SMCCC SOC ID recently for non-Linux based product. As the firmware remain same across OSes, user space is broken on Linux. > Aligning the Linux kernel with this > firmware-defined, OS-agnostic mechanism would reduce vendor-specific > dependencies and improve portability. Any gaps can be addressed by enhancing > userspace to correctly parse and consume this information. Agree. Updating entire use space would need time and we are looking to see if vendor specific interface can be given priority over the standard interface. > Given these > advantages, why would this approach not be the better long-term solution? As mentioned above, existing user space will be broken and fixing existing user space is going to take time. As the feature itself is "optional" from SMCCC specification, if we can't disable by default, we should at-least have a way to disable the feature by other means. [1] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/drivers/soc/qcom/socinfo.c?id=efb448d0a3fca01bb987dd70963da6185b81751e [2] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/drivers/firmware/smccc/soc_id.c?id=821b67fa46390baea0ac5139a60eaa48805261b2