# Buildroot linux on leon3s - please help

**URL:** <https://discourse.grlib.community/t/buildroot-linux-on-leon3s-please-help/580>\
**Category:** Uncategorized\
**Created:** [17 July 2026 08:20 UTC](https://discourse.grlib.community/t/buildroot-linux-on-leon3s-please-help/580 "2026-07-17T08:20:27Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![laurentiuduca](https://avatars.discourse-cdn.com/v4/letter/l/a88e4f/32.png) [@laurentiuduca](https://discourse.grlib.community/u/laurentiuduca)\
**Post date:** [17 July 2026 08:20 UTC](https://discourse.grlib.community/t/buildroot-linux-on-leon3s-please-help/580/1 "2026-07-17T08:20:27Z")

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hello,

i try to run linux on a leon3-digilent-arty-a7 based design and everything goes fine until i get the following message

Run /init as init process  
Unimplemented Sparc TRAP, type = 2b  
init(1): Whee… Hello Mr. Penguin [#1]  
CPU: 0 PID: 1 Comm: init Not tainted 5.10.246-leon1.10 #78  
Kernel panic - not syncing: Attempted to kill init! exitcode=0x0000000b

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<div class="post-metadata">

**Author:** ![laurentiuduca](https://avatars.discourse-cdn.com/v4/letter/l/a88e4f/32.png) [@laurentiuduca](https://discourse.grlib.community/u/laurentiuduca)\
**Post date:** [20 July 2026 10:07 UTC](https://discourse.grlib.community/t/buildroot-linux-on-leon3s-please-help/580/2 "2026-07-20T10:07:58Z")

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hello,  
if i disable casa in kernel, it boots until loading /init - which contains casa instructions.  
if i enable casa in linux kernel, it hangs at output/build/linux-5.10.246/arch/sparc/prom//init\_32.c, in the first printk  
(which calls #ifdef CONFIG\_SPARC\_LEON\_CAS \_\_cmpxchg\_u32(volatile int \*m, int old, int new) {..“casa [%2] 0xb, %3, %0”)}  
if i comment the printk also hangs.  
in all cases, the image.ram output of buildroot works in qemu.  
i have express tested casa in mklinuxing boot\_main and it works.  
can sparc-gaisler-linux-gcc be set to not generate casa instructions

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<div class="post-metadata">

**Author:** ![laurentiuduca](https://avatars.discourse-cdn.com/v4/letter/l/a88e4f/32.png) [@laurentiuduca](https://discourse.grlib.community/u/laurentiuduca)\
**Post date:** [23 July 2026 10:37 UTC](https://discourse.grlib.community/t/buildroot-linux-on-leon3s-please-help/580/3 "2026-07-23T10:37:27Z")

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with 2-way associative cache, set size 16k linux hangs

but with direct mapped cache, set size 1k linux boots