[tip: x86/platform] x86/platform/uv: Fix !KEXEC build failure

[tip-bot2 for Ingo Molnar]

The following commit has been merged into the x86/platform branch of tip:

Commit-ID:     c2209ea55612efac75de0a58ef5f7394fae7fa0f
Gitweb:        https://git.kernel.org/tip/c2209ea55612efac75de0a58ef5f7394fae7fa0f
Author:        Ingo Molnar <mingo@xxxxxxxxxx>
AuthorDate:    Tue, 20 Apr 2021 09:47:42 +02:00
Committer:     Ingo Molnar <mingo@xxxxxxxxxx>
CommitterDate: Tue, 20 Apr 2021 10:08:23 +02:00

x86/platform/uv: Fix !KEXEC build failure

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
---
 arch/x86/Kconfig | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 2792879..d9776c9 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -571,6 +571,7 @@ 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