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> + rseq_note_user_irq_entry(); > } > Looking at x86, both exc_debug_user() and exc_int3() invoke irqentry_enter_from_user_mode(), but there are various other traps that can come from userspace (e.g. math_error, exc_general_protection, ...). Some of those traps don't necessarily end with a signal delivery to the offending process. And some of those traps enable interrupts. So what happens if such a trap is triggered from userspace, and then scheduling happens on top of this trap ? Is this skipping rseq ip fixup and rseq fields updates ? Thanks, Mathieu -- Mathieu Desnoyers EfficiOS Inc. https://www.efficios.com