Fix automotive & snake demo halting after 512 compartment faults#88
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AlexJones0 merged 1 commit intolowRISC:mainfrom Apr 15, 2026
Merged
Fix automotive & snake demo halting after 512 compartment faults#88AlexJones0 merged 1 commit intolowRISC:mainfrom
AlexJones0 merged 1 commit intolowRISC:mainfrom
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See the comments (and provided links) for more info about this switcher limitation/interface. Signed-off-by: Alex Jones <alex.jones@lowrisc.org>
engdoreis
approved these changes
Apr 15, 2026
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Fix the bug in the automotive demo (and the same issue in the Snake demo, though practically this will never appear).
See the comments (and provided links) for more info about this switcher limitation/interface. As can be seen, this is documented in the include header for the CHERIoT RTOS core switcher, but as far as I could tell from a quick skim this gotcha doesn't seem to be noted anywhere in the public-facing docs or the programmer's guide.
As noted in that documentation, we need to set a flag inside the error handler and then reset the switcher's
errorHandlerCountattribute on the trusted stack frame from within our compartment, which we can do through aswitcher_handler_invocation_count_resetlibcall for. If we do this inside the handler we will instead get an integer overflow which will be interpreted by the switcher as a double fault.