if the syscall muxes are used, up to two additional argumentsmay be required. This means that the 8 required for mmap increasesup to 10 (for __syscall).

[jmg]

Summary

Sponsored by: Juniper Networks, Inc.

the program in test plan will allow a normal user to cause a panic on any system that has the EL0 32 processor feature. This is all aarch64 systems except for Apple's Mx processors and Cavium's ThunderX processors.

Test Plan

make sure that this program doesn't cause a crash:

#include <sys/syscall.h>
#include <unistd.h>

int
main()
{
	int i;

	i = syscall(SYS_mmap, 0, 1, 2, 3, 4, 5, 6, 7);

	i = __syscall((quad_t)SYS_mmap << 32, 0, 1, 2, 3, 4, 5, 6, 7);

	return 0;
}

(note that the second call will be fixed to not require this word swap via a different commit)

[andrew]

It looks like sendfile and wait6 are also affected.

This is all aarch64 systems except for Apple's Mx processors and Cavium's ThunderX processors.

The selection of Armv9 CPU TRMs I looked at have no support for AArch32 at any exception level, e.g. Cortex-X2, Cortex-A520, and Neoverse-V3.

[markj]

In the commit log, please be sure to have a separate subject line, e.g., arm64: ...: https://docs.freebsd.org/en/articles/committers-guide/#_start_with_a_subject_line

The review title here looks like it should be the review description.

[jmg]

I forgot to tag the commit. This was committed in: https://cgit.freebsd.org/src/commit/?id=740b879c6ade531adebeba7cd2f261bbe650797f