# \[Kernel\] Caught cap fault in send phase while trying to handle vm fault

**URL:** <https://sel4.discourse.group/t/kernel-caught-cap-fault-in-send-phase-while-trying-to-handle-vm-fault/879>\
**Category:** New to seL4\
**Tags:** arm\
**Created:** [September 5, 2024, 8:02am UTC](https://sel4.discourse.group/t/kernel-caught-cap-fault-in-send-phase-while-trying-to-handle-vm-fault/879 "2024-09-05T08:02:49Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![Init\_vishal](https://avatars.discourse-cdn.com/v4/letter/i/9e8a1a/32.png) [@Init\_vishal](https://sel4.discourse.group/u/Init_vishal)\
**Post date:** [September 5, 2024, 8:02am UTC](https://sel4.discourse.group/t/kernel-caught-cap-fault-in-send-phase-while-trying-to-handle-vm-fault/879/1 "2024-09-05T08:02:49Z")

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Hi seL4 community,  
I have ported sel4 to NXP S32G RBD3 board. It runs fine till kernel but just before dropping to the user space. after that in the debug serial terminal, i am encountering below errors :  
"Caught cap fault in send phase at address 0  
while trying to handle :  
vm fault on code at address 0 with status 0x82000006 "  
How to proceed further on this error ? Any idea or lead would be really helpful.

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**Author:** ![Indan](https://yyz2.discourse-cdn.com/free1/user_avatar/sel4.discourse.group/indan/32/185_2.png) [@Indan](https://sel4.discourse.group/u/Indan)\
**Post date:** [September 6, 2024, 10:20am UTC](https://sel4.discourse.group/t/kernel-caught-cap-fault-in-send-phase-while-trying-to-handle-vm-fault/879/2 "2024-09-06T10:20:59Z")

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VM fault means your application caused a virtual memory fault (segfault), probably at address 0x82000006. The initial task has no fault handler, hence first error message, but ignore that, focus on the actual fault.

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**Author:** ![Init\_vishal](https://avatars.discourse-cdn.com/v4/letter/i/9e8a1a/32.png) [@Init\_vishal](https://sel4.discourse.group/u/Init_vishal)\
**Post date:** [September 17, 2024, 11:23am UTC](https://sel4.discourse.group/t/kernel-caught-cap-fault-in-send-phase-while-trying-to-handle-vm-fault/879/3 "2024-09-17T11:23:18Z")

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Thankyou Indan for the lead, I am able to locate the root cause and resolve the issue by suspending my own TCB to exit more “cleanly”, which means when the root task exists, it should simply suspend itself, so it dose not give you Stack DUMP with a CRASH. No more CAP/Virtual Memory fault observed.