Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 65479472 authored by Wen Congyang's avatar Wen Congyang Committed by Rafael J. Wysocki
Browse files

ACPI / memhotplug: don't allow to eject the memory device if it is being used 



We eject the memory device even if it is in use.  It is very dangerous,
and it will cause the kernel to be panicked.

Signed-off-by: default avatarWen Congyang <wency@cn.fujitsu.com>
Reviewed-by: default avatarYasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Acked-by: default avatarDavid Rientjes <rientjes@google.com>
Signed-off-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
parent e0b7b24d

drivers/acpi/acpi_memhotplug.c

+33 −9
Original line number Diff line number Diff line
@@ -78,6 +78,7 @@ struct acpi_memory_info { 
	unsigned short caching;	/* memory cache attribute */

	unsigned short write_protect;	/* memory read/write attribute */

	unsigned int enabled:1;

	unsigned int failed:1;

};



struct acpi_memory_device {
@@ -257,9 +258,23 @@ static int acpi_memory_enable_device(struct acpi_memory_device *mem_device) 
			node = memory_add_physaddr_to_nid(info->start_addr);



		result = add_memory(node, info->start_addr, info->length);

		if (result)



		/*

		 * If the memory block has been used by the kernel, add_memory()

		 * returns -EEXIST. If add_memory() returns the other error, it

		 * means that this memory block is not used by the kernel.

		 */

		if (result && result != -EEXIST) {

			info->failed = 1;

			continue;

		}



		if (!result)

			info->enabled = 1;

		/*

		 * Add num_enable even if add_memory() returns -EEXIST, so the

		 * device is bound to this driver.

		 */

		num_enabled++;

	}

	if (!num_enabled) {
@@ -280,21 +295,30 @@ static int acpi_memory_enable_device(struct acpi_memory_device *mem_device) 


static int acpi_memory_remove_memory(struct acpi_memory_device *mem_device)

{

	int result;

	int result = 0;

	struct acpi_memory_info *info, *n;



	list_for_each_entry_safe(info, n, &mem_device->res_list, list) {

		if (info->enabled) {

		if (info->failed)

			/* The kernel does not use this memory block */

			continue;



		if (!info->enabled)

			/*

			 * The kernel uses this memory block, but it may be not

			 * managed by us.

			 */

			return -EBUSY;



		result = remove_memory(info->start_addr, info->length);

		if (result)

			return result;

		}



		list_del(&info->list);

		kfree(info);

	}



	return 0;

	return result;

}



static void acpi_memory_device_notify(acpi_handle handle, u32 event, void *data)