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| author | Nathan Chancellor <nathan@kernel.org> | 2024-02-03 02:53:21 +0300 |
|---|---|---|
| committer | Paolo Bonzini <pbonzini@redhat.com> | 2024-02-06 11:56:04 +0300 |
| commit | e459647710070684a48384d67742822379de8c1c (patch) | |
| tree | 6d330f991eaa22eb36bcf63789bec0aa1966e641 /arch | |
| parent | a9ef277488cfc1b7da88235dc11c338a14f34835 (diff) | |
| download | linux-e459647710070684a48384d67742822379de8c1c.tar.xz | |
x86/coco: Define cc_vendor without CONFIG_ARCH_HAS_CC_PLATFORM
After commit a9ef277488cf ("x86/kvm: Fix SEV check in
sev_map_percpu_data()"), there is a build error when building
x86_64_defconfig with GCOV using LLVM:
ld.lld: error: undefined symbol: cc_vendor
>>> referenced by kvm.c
>>> arch/x86/kernel/kvm.o:(kvm_smp_prepare_boot_cpu) in archive vmlinux.a
which corresponds to
if (cc_vendor != CC_VENDOR_AMD ||
!cc_platform_has(CC_ATTR_GUEST_MEM_ENCRYPT))
return;
Without GCOV, clang is able to eliminate the use of cc_vendor because
cc_platform_has() evaluates to false when CONFIG_ARCH_HAS_CC_PLATFORM is
not set, meaning that if statement will be true no matter what value
cc_vendor has.
With GCOV, the instrumentation keeps the use of cc_vendor around for
code coverage purposes but cc_vendor is only declared, not defined,
without CONFIG_ARCH_HAS_CC_PLATFORM, leading to the build error above.
Provide a macro definition of cc_vendor when CONFIG_ARCH_HAS_CC_PLATFORM
is not set with a value of CC_VENDOR_NONE, so that the first condition
can always be evaluated/eliminated at compile time, avoiding the build
error altogether. This is very similar to the situation prior to
commit da86eb961184 ("x86/coco: Get rid of accessor functions").
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Acked-by: Borislav Petkov (AMD) <bp@alien8.de>
Message-Id: <20240202-provide-cc_vendor-without-arch_has_cc_platform-v1-1-09ad5f2a3099@kernel.org>
Fixes: a9ef277488cf ("x86/kvm: Fix SEV check in sev_map_percpu_data()", 2024-01-31)
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/x86/include/asm/coco.h | 5 |
1 files changed, 3 insertions, 2 deletions
diff --git a/arch/x86/include/asm/coco.h b/arch/x86/include/asm/coco.h index 6ae2d16a7613..76c310b19b11 100644 --- a/arch/x86/include/asm/coco.h +++ b/arch/x86/include/asm/coco.h @@ -10,13 +10,14 @@ enum cc_vendor { CC_VENDOR_INTEL, }; -extern enum cc_vendor cc_vendor; - #ifdef CONFIG_ARCH_HAS_CC_PLATFORM +extern enum cc_vendor cc_vendor; void cc_set_mask(u64 mask); u64 cc_mkenc(u64 val); u64 cc_mkdec(u64 val); #else +#define cc_vendor (CC_VENDOR_NONE) + static inline u64 cc_mkenc(u64 val) { return val; |