Commit 09eea7ad authored by Long Li's avatar Long Li Committed by Wei Liu
Browse files

Drivers: hv: Allocate interrupt and monitor pages aligned to system page boundary 



There are use cases that interrupt and monitor pages are mapped to
user-mode through UIO, so they need to be system page aligned. Some
Hyper-V allocation APIs introduced earlier broke those requirements.

Fix this by using page allocation functions directly for interrupt
and monitor pages.

Cc: stable@vger.kernel.org
Fixes: ca48739e ("Drivers: hv: vmbus: Move Hyper-V page allocator to arch neutral code")
Signed-off-by: default avatarLong Li <longli@microsoft.com>
Reviewed-by: default avatarMichael Kelley <mhklinux@outlook.com>
Link: https://lore.kernel.org/r/1746492997-4599-2-git-send-email-longli@linuxonhyperv.com


Signed-off-by: default avatarWei Liu <wei.liu@kernel.org>
Message-ID: <1746492997-4599-2-git-send-email-longli@linuxonhyperv.com>
parent 43cb39ad

drivers/hv/connection.c

+17 −6
Original line number Diff line number Diff line
@@ -206,11 +206,20 @@ int vmbus_connect(void) 
	INIT_LIST_HEAD(&vmbus_connection.chn_list);

	mutex_init(&vmbus_connection.channel_mutex);



	/*

	 * The following Hyper-V interrupt and monitor pages can be used by

	 * UIO for mapping to user-space, so they should always be allocated on

	 * system page boundaries. The system page size must be >= the Hyper-V

	 * page size.

	 */

	BUILD_BUG_ON(PAGE_SIZE < HV_HYP_PAGE_SIZE);



	/*

	 * Setup the vmbus event connection for channel interrupt

	 * abstraction stuff

	 */

	vmbus_connection.int_page = hv_alloc_hyperv_zeroed_page();

	vmbus_connection.int_page =

		(void *)__get_free_page(GFP_KERNEL | __GFP_ZERO);

	if (vmbus_connection.int_page == NULL) {

		ret = -ENOMEM;

		goto cleanup;
@@ -225,8 +234,8 @@ int vmbus_connect(void) 
	 * Setup the monitor notification facility. The 1st page for

	 * parent->child and the 2nd page for child->parent

	 */

	vmbus_connection.monitor_pages[0] = hv_alloc_hyperv_page();

	vmbus_connection.monitor_pages[1] = hv_alloc_hyperv_page();

	vmbus_connection.monitor_pages[0] = (void *)__get_free_page(GFP_KERNEL);

	vmbus_connection.monitor_pages[1] = (void *)__get_free_page(GFP_KERNEL);

	if ((vmbus_connection.monitor_pages[0] == NULL) ||

	    (vmbus_connection.monitor_pages[1] == NULL)) {

		ret = -ENOMEM;
@@ -342,21 +351,23 @@ void vmbus_disconnect(void) 
		destroy_workqueue(vmbus_connection.work_queue);



	if (vmbus_connection.int_page) {

		hv_free_hyperv_page(vmbus_connection.int_page);

		free_page((unsigned long)vmbus_connection.int_page);

		vmbus_connection.int_page = NULL;

	}



	if (vmbus_connection.monitor_pages[0]) {

		if (!set_memory_encrypted(

			(unsigned long)vmbus_connection.monitor_pages[0], 1))

			hv_free_hyperv_page(vmbus_connection.monitor_pages[0]);

			free_page((unsigned long)

				vmbus_connection.monitor_pages[0]);

		vmbus_connection.monitor_pages[0] = NULL;

	}



	if (vmbus_connection.monitor_pages[1]) {

		if (!set_memory_encrypted(

			(unsigned long)vmbus_connection.monitor_pages[1], 1))

			hv_free_hyperv_page(vmbus_connection.monitor_pages[1]);

			free_page((unsigned long)

				vmbus_connection.monitor_pages[1]);

		vmbus_connection.monitor_pages[1] = NULL;

	}

}