5.15-stable review patch. If anyone has any objections, please let me know.
------------------
From: Christoph Hellwig hch@lst.de
[ Upstream commit fbdee71bb5d8d054e1bdb5af4c540f2cb86fe296 ]
Make the legacy dev_t based autoloading optional and add a deprecation warning. This kind of autoloading has ceased to be useful about 20 years ago.
Signed-off-by: Christoph Hellwig hch@lst.de Link: https://lore.kernel.org/r/20220104071647.164918-1-hch@lst.de Signed-off-by: Jens Axboe axboe@kernel.dk Stable-dep-of: 457ef47c08d2 ("block: retry call probe after request_module in blk_request_module") Signed-off-by: Sasha Levin sashal@kernel.org --- block/Kconfig | 12 ++++++++++++ block/bdev.c | 9 ++++++--- block/genhd.c | 6 ++++++ 3 files changed, 24 insertions(+), 3 deletions(-)
diff --git a/block/Kconfig b/block/Kconfig index 8e28ae7718bd2..0d415226e3daa 100644 --- a/block/Kconfig +++ b/block/Kconfig @@ -26,6 +26,18 @@ menuconfig BLOCK
if BLOCK
+config BLOCK_LEGACY_AUTOLOAD + bool "Legacy autoloading support" + help + Enable loading modules and creating block device instances based on + accesses through their device special file. This is a historic Linux + feature and makes no sense in a udev world where device files are + created on demand. + + Say N here unless booting or other functionality broke without it, in + which case you should also send a report to your distribution and + linux-block@vger.kernel.org. + config BLK_RQ_ALLOC_TIME bool
diff --git a/block/bdev.c b/block/bdev.c index b8599a4088843..85c090ef3bf2c 100644 --- a/block/bdev.c +++ b/block/bdev.c @@ -736,12 +736,15 @@ struct block_device *blkdev_get_no_open(dev_t dev) struct inode *inode;
inode = ilookup(blockdev_superblock, dev); - if (!inode) { + if (!inode && IS_ENABLED(CONFIG_BLOCK_LEGACY_AUTOLOAD)) { blk_request_module(dev); inode = ilookup(blockdev_superblock, dev); - if (!inode) - return NULL; + if (inode) + pr_warn_ratelimited( +"block device autoloading is deprecated. It will be removed in Linux 5.19\n"); } + if (!inode) + return NULL;
/* switch from the inode reference to a device mode one: */ bdev = &BDEV_I(inode)->bdev; diff --git a/block/genhd.c b/block/genhd.c index 88d1a6385a242..2f66745de5d5a 100644 --- a/block/genhd.c +++ b/block/genhd.c @@ -182,7 +182,9 @@ static struct blk_major_name { struct blk_major_name *next; int major; char name[16]; +#ifdef CONFIG_BLOCK_LEGACY_AUTOLOAD void (*probe)(dev_t devt); +#endif } *major_names[BLKDEV_MAJOR_HASH_SIZE]; static DEFINE_MUTEX(major_names_lock); static DEFINE_SPINLOCK(major_names_spinlock); @@ -269,7 +271,9 @@ int __register_blkdev(unsigned int major, const char *name, }
p->major = major; +#ifdef CONFIG_BLOCK_LEGACY_AUTOLOAD p->probe = probe; +#endif strlcpy(p->name, name, sizeof(p->name)); p->next = NULL; index = major_to_index(major); @@ -669,6 +673,7 @@ static ssize_t disk_badblocks_store(struct device *dev, return badblocks_store(disk->bb, page, len, 0); }
+#ifdef CONFIG_BLOCK_LEGACY_AUTOLOAD void blk_request_module(dev_t devt) { unsigned int major = MAJOR(devt); @@ -688,6 +693,7 @@ void blk_request_module(dev_t devt) /* Make old-style 2.4 aliases work */ request_module("block-major-%d", MAJOR(devt)); } +#endif /* CONFIG_BLOCK_LEGACY_AUTOLOAD */
/* * print a full list of all partitions - intended for places where the root