acrn-kernel/arch/x86/realmode
Juergen Gross b189879377 x86/boot: Skip realmode init code when running as Xen PV guest
[ Upstream commit f1e5250094 ]

When running as a Xen PV guest there is no need for setting up the
realmode trampoline, as realmode isn't supported in this environment.

Trying to setup the trampoline has been proven to be problematic in
some cases, especially when trying to debug early boot problems with
Xen requiring to keep the EFI boot-services memory mapped (some
firmware variants seem to claim basically all memory below 1Mb for boot
services).

Introduce new x86_platform_ops operations for that purpose, which can
be set to a NOP by the Xen PV specific kernel boot code.

  [ bp: s/call_init_real_mode/do_init_real_mode/ ]

Fixes: 084ee1c641 ("x86, realmode: Relocator for realmode code")
Suggested-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lore.kernel.org/r/20221123114523.3467-1-jgross@suse.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-12-31 13:32:16 +01:00
..
rm x86: kmsan: disable instrumentation of unsupported code 2022-10-03 14:03:24 -07:00
Makefile x86, objtool: Dont exclude arch/x86/realmode/ 2021-05-12 14:54:54 +02:00
init.c x86/boot: Skip realmode init code when running as Xen PV guest 2022-12-31 13:32:16 +01:00
rmpiggy.S x86/asm/realmode: Use SYM_DATA_* instead of GLOBAL 2019-10-18 11:28:47 +02:00