Commit-ID: 999696752db1099aba595aac4f8d881f8c7cf4e6 Gitweb: https://git.kernel.org/tip/999696752db1099aba595aac4f8d881f8c7cf4e6 Author: Juergen Gross <[email protected]> AuthorDate: Wed, 12 Sep 2018 19:41:22 +0200 Committer: Ingo Molnar <[email protected]> CommitDate: Wed, 12 Sep 2018 21:15:02 +0200
x86/xen: Disable CPU0 hotplug for Xen PV Xen PV guests don't allow CPU0 hotplug, so disable it. Signed-off-by: Juergen Gross <[email protected]> Cc: Linus Torvalds <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: [email protected] Cc: [email protected] Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Ingo Molnar <[email protected]> --- arch/x86/kernel/topology.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/arch/x86/kernel/topology.c b/arch/x86/kernel/topology.c index 12cbe2b88c0f..738bf42b0218 100644 --- a/arch/x86/kernel/topology.c +++ b/arch/x86/kernel/topology.c @@ -111,8 +111,10 @@ int arch_register_cpu(int num) /* * Currently CPU0 is only hotpluggable on Intel platforms. Other * vendors can add hotplug support later. + * Xen PV guests don't support CPU0 hotplug at all. */ - if (c->x86_vendor != X86_VENDOR_INTEL) + if (c->x86_vendor != X86_VENDOR_INTEL || + boot_cpu_has(X86_FEATURE_XENPV)) cpu0_hotpluggable = 0; /*

