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x86/xen: fill hypercall page with int3
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Authored by royger on Feb 16 2024, 12:15 PM.
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Details

Summary

Filling the hypercall page with nops is not helpful from a debugging point of
view, as for example attempting to execute an hypercall before the page is
initialized will result in the execution flow falling through into
xen_start32, making the mistake less obvious to spot.

Instead fill the page with int3 (0xcc) which will result in a #BP trap.

Sponsored by: Cloud Software Group

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rG FreeBSD src repository
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