[ Upstream commit f71e1d2ff8 ]
The SYSCALL instruction cannot really be disabled in compatibility mode.
The best that can be done is to configure the CSTAR msr to point to a
minimal handler. Currently this handler has a rather misleading name -
ignore_sysret() as it's not really doing anything with sysret.
Give it a more descriptive name.
Signed-off-by: Nikolay Borisov <nik.borisov@suse.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20230623111409.3047467-3-nik.borisov@suse.com
Stable-dep-of: ac8b270b61 ("x86/bhi: Avoid warning in #DB handler due to BHI mitigation")
Signed-off-by: Sasha Levin <sashal@kernel.org>