Commit 0592969e authored by Jason Wang's avatar Jason Wang Committed by Greg Kroah-Hartman
Browse files

hv: fail the probing immediately when we are not in hyperv platform 



We wait for about 5 seconds for the success of the hyperv registration even if
we were not in hyperv platform. This is suboptimal, so the patch check the cpuid
in the beginning of hv_acpi_init() instead of in vmbus_bus_init() to fail the
probing immediately.

Signed-off-by: default avatarJason Wang <jasowang@redhat.com>
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Acked-by: default avatarK. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 4a52c4af

drivers/hv/hv.c

+0 −25
Original line number Diff line number Diff line
@@ -38,28 +38,6 @@ struct hv_context hv_context = { 
	.signal_event_buffer	= NULL,

};



/*

 * query_hypervisor_presence

 * - Query the cpuid for presence of windows hypervisor

 */

static int query_hypervisor_presence(void)

{

	unsigned int eax;

	unsigned int ebx;

	unsigned int ecx;

	unsigned int edx;

	unsigned int op;



	eax = 0;

	ebx = 0;

	ecx = 0;

	edx = 0;

	op = HVCPUID_VERSION_FEATURES;

	cpuid(op, &eax, &ebx, &ecx, &edx);



	return ecx & HV_PRESENT_BIT;

}



/*

 * query_hypervisor_info - Get version info of the windows hypervisor

 */
@@ -160,9 +138,6 @@ int hv_init(void) 
	memset(hv_context.synic_message_page, 0,

	       sizeof(void *) * NR_CPUS);



	if (!query_hypervisor_presence())

		goto cleanup;



	max_leaf = query_hypervisor_info();



	/*

drivers/hv/vmbus_drv.c

+25 −0
Original line number Diff line number Diff line
@@ -719,10 +719,35 @@ static struct acpi_driver vmbus_acpi_driver = { 
	},

};



/*

 * query_hypervisor_presence

 * - Query the cpuid for presence of windows hypervisor

 */

static int query_hypervisor_presence(void)

{

	unsigned int eax;

	unsigned int ebx;

	unsigned int ecx;

	unsigned int edx;

	unsigned int op;



	eax = 0;

	ebx = 0;

	ecx = 0;

	edx = 0;

	op = HVCPUID_VERSION_FEATURES;

	cpuid(op, &eax, &ebx, &ecx, &edx);



	return ecx & HV_PRESENT_BIT;

}



static int __init hv_acpi_init(void)

{

	int ret, t;



	if (!query_hypervisor_presence())

		return -ENODEV;



	init_completion(&probe_event);



	/*

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