[PATCH 4.9 119/240] x86/platform/uv: Fix !KEXEC build failure

[Greg Kroah-Hartman]

From: Ingo Molnar <mingo@xxxxxxxxxx>

[ Upstream commit c2209ea55612efac75de0a58ef5f7394fae7fa0f ]

When KEXEC is disabled, the UV build fails:

  arch/x86/platform/uv/uv_nmi.c:875:14: error: ‘uv_nmi_kexec_failed’ undeclared (first use in this function)

Since uv_nmi_kexec_failed is only defined in the KEXEC_CORE #ifdef branch,
this code cannot ever have been build tested:

	if (main)
		pr_err("UV: NMI kdump: KEXEC not supported in this kernel\n");
	atomic_set(&uv_nmi_kexec_failed, 1);

Nor is this use possible in uv_handle_nmi():

                atomic_set(&uv_nmi_kexec_failed, 0);

These bugs were introduced in this commit:

    d0a9964e9873: ("x86/platform/uv: Implement simple dump failover if kdump fails")

Which added the uv_nmi_kexec_failed assignments to !KEXEC code, while making the
definition KEXEC-only - apparently without testing the !KEXEC case.

Instead of complicating the #ifdef maze, simplify the code by requiring X86_UV
to depend on KEXEC_CORE. This pattern is present in other architectures as well.

( We'll remove the untested, 7 years old !KEXEC complications from the file in a
  separate commit. )

Fixes: d0a9964e9873: ("x86/platform/uv: Implement simple dump failover if kdump fails")
Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: Mike Travis <travis@xxxxxxx>
Cc: linux-kernel@xxxxxxxxxxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 arch/x86/Kconfig | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 80636caee07c..3ce5b5bd1dc4 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -495,6 +495,7 @@ config X86_UV
 	depends on X86_EXTENDED_PLATFORM
 	depends on NUMA
 	depends on EFI
+	depends on KEXEC_CORE
 	depends on X86_X2APIC
 	depends on PCI
 	---help---
-- 
2.30.2