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X-MS-Exchange-AntiSpam-ExternalHop-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-ExternalHop-MessageData-0: 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 X-OriginatorOrg: sony.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 23 Apr 2025 10:10:48.3261 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: 2e7ac1cc-49bd-48dd-1543-08dd824f1f00 X-MS-Exchange-CrossTenant-Id: 66c65d8a-9158-4521-a2d8-664963db48e4 X-MS-Exchange-CrossTenant-OriginalAttributedTenantConnectingIp: TenantId=66c65d8a-9158-4521-a2d8-664963db48e4;Ip=[121.100.38.196];Helo=[gepdcl07.sg.gdce.sony.com.sg] X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-AuthSource: TreatMessagesAsInternal-BN1PEPF00004681.namprd03.prod.outlook.com X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: CH2PR13MB3861 X-Proofpoint-GUID: i5laYOotmuhOPORQRTaCTlG1wbm5HEEn X-Proofpoint-Spam-Details-Enc: AW1haW4tMjUwNDIzMDA2OSBTYWx0ZWRfX72cgt3CUyyBR kXNjDyGbf5c1ER4TeR/4wYhhA0rdxUaDAV/OtVcs4ZGX0I+WXCT5Ur+WVGariH3X1wrX7B55vqo pK6R6SR8Z9+/b59ZB8XjXrre0rFBJKAYQA5U0tDdXqbG02RuDv3La2mhUswEiedxI008V8jS2F1 w8CiA1nJLMLSMP2Ueb7j9cn2KtiZDifjwafg10p9OIryze7bJXGtGUzaYpgao6nmw6Y4acBcrFg Ic4Cd1wH+V/AuJ5TkOPeF6cx5cv70oGsWwQYHv6fFKXUPsc0hwx0R+/lc33wwd/g/PDMZ/3NQKg /lxEGX/4L4hyNN+Jh4j7mEGHGnK4K2clyGZQLpQtaszg6TYdWbwGF87FBdcfV16pH/g0yrdySrH BVy6m0xN X-Proofpoint-ORIG-GUID: i5laYOotmuhOPORQRTaCTlG1wbm5HEEn X-Sony-Outbound-GUID: i5laYOotmuhOPORQRTaCTlG1wbm5HEEn X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1099,Hydra:6.0.680,FMLib:17.12.68.34 definitions=2025-04-23_07,2025-04-22_01,2024-11-22_01 On Thu, Feb 16, 2023 at 11:45:58AM +0106, John Ogness wrote: > The ttynull driver does not provide an implementation for the write() > callback. This leads to a NULL pointer dereference in the related > printing kthread, which assumes it can call that callback. > > Do not create kthreads for consoles that do not implement the write() > callback. Also, for pr_flush(), ignore consoles that do not implement > write() or write_atomic() since there is no way those consoles can > flush their output. > > --- > This is only a problem for the PREEMPT_RT tree. Mainline does not have > this problem. Sorry for resurrecting this old thread but we actually want this patch in 5.15-rt. I am not sure why this was not applied to 5.15-rt yet since it is already applied to 5.10-rt. Could you please consider to pick this for 5.15-rt? Best regards, Krishanth