Commit 28df8580 authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge tag 'hyperv-fixes-signed-20210119' of... 

Merge tag 'hyperv-fixes-signed-20210119' of git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux

Pull hyperv fix from Wei Liu:
 "One patch from Dexuan to fix clockevent initialization"

* tag 'hyperv-fixes-signed-20210119' of git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux:
  x86/hyperv: Initialize clockevents after LAPIC is initialized
parents 1e2a199f fff7b5e6

arch/x86/hyperv/hv_init.c

+26 −3
Original line number Diff line number Diff line
@@ -315,6 +315,25 @@ static struct syscore_ops hv_syscore_ops = { 
	.resume		= hv_resume,

};



static void (* __initdata old_setup_percpu_clockev)(void);



static void __init hv_stimer_setup_percpu_clockev(void)

{

	/*

	 * Ignore any errors in setting up stimer clockevents

	 * as we can run with the LAPIC timer as a fallback.

	 */

	(void)hv_stimer_alloc();



	/*

	 * Still register the LAPIC timer, because the direct-mode STIMER is

	 * not supported by old versions of Hyper-V. This also allows users

	 * to switch to LAPIC timer via /sys, if they want to.

	 */

	if (old_setup_percpu_clockev)

		old_setup_percpu_clockev();

}



/*

 * This function is to be invoked early in the boot sequence after the

 * hypervisor has been detected.
@@ -393,10 +412,14 @@ void __init hyperv_init(void) 
	wrmsrl(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64);



	/*

	 * Ignore any errors in setting up stimer clockevents

	 * as we can run with the LAPIC timer as a fallback.

	 * hyperv_init() is called before LAPIC is initialized: see

	 * apic_intr_mode_init() -> x86_platform.apic_post_init() and

	 * apic_bsp_setup() -> setup_local_APIC(). The direct-mode STIMER

	 * depends on LAPIC, so hv_stimer_alloc() should be called from

	 * x86_init.timers.setup_percpu_clockev.

	 */

	(void)hv_stimer_alloc();

	old_setup_percpu_clockev = x86_init.timers.setup_percpu_clockev;

	x86_init.timers.setup_percpu_clockev = hv_stimer_setup_percpu_clockev;



	hv_apic_init();