From: Ammar Faizi <ammarfaizi2@xxxxxxxxxxx> This is an RFC patchset v3: sysret_rip test update for Intel FRED architecture. Xin Li reported sysret_rip test fails at: assert(ctx->uc_mcontext.gregs[REG_EFL] == ctx->uc_mcontext.gregs[REG_R11]); in a FRED system. Let's handle the FRED system scenario too. The 'syscall' instruction in a FRED system doesn't set %r11=%rflags. There are two patches in this series. How to test this: $ make -C tools/testing/selftests/x86 $ tools/testing/selftests/x86/sysret_rip_64 Link: https://lore.kernel.org/lkml/5d4ad3e3-034f-c7da-d141-9c001c2343af@xxxxxxxxx Fixes: 660602140103 ("selftests/x86: Add a selftest for SYSRET to noncanonical addresses") Link: https://lore.kernel.org/lkml/25b96960-a07e-a952-5c23-786b55054126@xxxxxxxxx Reported-by: Xin Li <xin3.li@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> --- ## Changelog v3: - Test that we don't get a mix of REGS_SAVED and REGS_SYSRET, which is a major part of the point (hpa). ## Changelog v2: - Use "+r"(rsp) as the right way to avoid redzone problems per Andrew's comment (hpa). (Ref: https://lore.kernel.org/lkml/8f5c24df-514d-5d89-f58f-ec8c3eb1e049@xxxxxxxxx ) --- Ammar Faizi (2): selftests/x86: sysret_rip: Handle syscall in a FRED system selftests/x86: sysret_rip: Add more syscall tests with respect to `%rcx` and `%r11` tools/testing/selftests/x86/sysret_rip.c | 120 ++++++++++++++++++++++- 1 file changed, 119 insertions(+), 1 deletion(-) base-commit: e12ad468c22065a2826b2fc4c11d2113a7975301 -- Ammar Faizi