Dexuan Cui 86e619c922 x86/hyperv: Fix undefined reference to isolation_type_en_snp without CONFIG_HYPERV
When CONFIG_HYPERV is not set, arch/x86/hyperv/ivm.c is not built (see
arch/x86/Kbuild), so 'isolation_type_en_snp' in the ivm.c is not defined,
and this failure happens:

ld: arch/x86/kernel/cpu/mshyperv.o: in function `ms_hyperv_init_platform':
arch/x86/kernel/cpu/mshyperv.c:417: undefined reference to `isolation_type_en_snp'

Fix the failure by testing hv_get_isolation_type() and
ms_hyperv.paravisor_present for a fully enlightened SNP VM: when
CONFIG_HYPERV is not set, hv_get_isolation_type() is defined as a
static inline function that always returns HV_ISOLATION_TYPE_NONE
(see include/asm-generic/mshyperv.h), so the compiler won't generate any
code for the ms_hyperv.paravisor_present and static_branch_enable().

Reported-by: Tom Lendacky <thomas.lendacky@amd.com>
Closes: https://lore.kernel.org/lkml/b4979997-23b9-0c43-574e-e4a3506500ff@amd.com/
Fixes: d6e2d65244 ("x86/hyperv: Add sev-snp enlightened guest static key")
Signed-off-by: Dexuan Cui <decui@microsoft.com>
Signed-off-by: Wei Liu <wei.liu@kernel.org>
Link: https://lore.kernel.org/r/20230823032008.18186-1-decui@microsoft.com
2023-08-23 05:42:20 +00:00
2022-09-28 09:02:20 +02:00
2023-07-30 13:23:47 -07:00

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.
Description
No description provided
Readme 7.9 GiB
Languages
C 97.7%
Assembly 1.6%
Makefile 0.3%
Perl 0.1%