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: ca48739e59 ("Drivers: hv: vmbus: Move Hyper-V page allocator to arch neutral code")
Signed-off-by: Long Li <longli@microsoft.com>
Reviewed-by: Michael Kelley <mhklinux@outlook.com>
Link: https://lore.kernel.org/r/1746492997-4599-2-git-send-email-longli@linuxonhyperv.com
Signed-off-by: Wei Liu <wei.liu@kernel.org>
Message-ID: <1746492997-4599-2-git-send-email-longli@linuxonhyperv.com>
This commit is contained in:
Long Li 2025-05-05 17:56:33 -07:00 committed by Wei Liu
parent 43cb39ad26
commit 09eea7ad0b

View File

@ -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;
}
}