On 1/24/23 02:09, Ammar Faizi wrote:
From: Ammar Faizi <ammarfaizi2@xxxxxxxxxxx> Test that: - "syscall" in a FRED system doesn't clobber %rcx and %r11. - "syscall" in a non-FRED system sets %rcx=%rip and %r11=%rflags. Test them out with a trivial system call like __NR_getppid and friends which are extremely likely to return with SYSRET on an IDT system. Link: https://lore.kernel.org/lkml/25b96960-a07e-a952-5c23-786b55054126@xxxxxxxxx Co-developed-by: H. Peter Anvin (Intel) <hpa@xxxxxxxxx> Signed-off-by: H. Peter Anvin (Intel) <hpa@xxxxxxxxx> Acked-by: H. Peter Anvin (Intel) <hpa@xxxxxxxxx> Signed-off-by: Ammar Faizi <ammarfaizi2@xxxxxxxxxxx>
Add to the description that the purpose of this is to ensure that various system calls are *consistent*, as per the comment immediately below your code.
-hpa
