This patch applyes the introduced pm_runtime_set_memalloc_noio on block device so that PM core will teach mm to not allocate memory with GFP_IOFS when calling the runtime_resume callback for block devices. Cc: Jens Axboe <axboe@xxxxxxxxx> Signed-off-by: Ming Lei <ming.lei@xxxxxxxxxxxxx> --- block/genhd.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/block/genhd.c b/block/genhd.c index 9e02cd6..c5f10ea 100644 --- a/block/genhd.c +++ b/block/genhd.c @@ -18,6 +18,7 @@ #include <linux/mutex.h> #include <linux/idr.h> #include <linux/log2.h> +#include <linux/pm_runtime.h> #include "blk.h" @@ -519,6 +520,12 @@ static void register_disk(struct gendisk *disk) dev_set_name(ddev, disk->disk_name); + /* avoid probable deadlock caused by allocate memory with + * GFP_KERNEL in runtime_resume callback of its all ancestor + * deivces + */ + pm_runtime_set_memalloc_noio(ddev, true); + /* delay uevents, until we scanned partition table */ dev_set_uevent_suppress(ddev, 1); @@ -661,6 +668,7 @@ void del_gendisk(struct gendisk *disk) disk->driverfs_dev = NULL; if (!sysfs_deprecated) sysfs_remove_link(block_depr, dev_name(disk_to_dev(disk))); + pm_runtime_set_memalloc_noio(disk_to_dev(disk), false); device_del(disk_to_dev(disk)); } EXPORT_SYMBOL(del_gendisk); -- 1.7.9.5 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>