This is a note to let you know that I've just added the patch titled
block: deprecate autoloading based on dev_t
to the 5.15-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
block-deprecate-autoloading-based-on-dev_t.patch
and it can be found in the queue-5.15 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 967a67700b5865bbbf85be1fb1f0fcf14c525521
Author: Christoph Hellwig <hch@xxxxxx>
Date: Tue Jan 4 08:16:47 2022 +0100
block: deprecate autoloading based on dev_t
[ 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@xxxxxx>
Link: https://lore.kernel.org/r/20220104071647.164918-1-hch@xxxxxx
Signed-off-by: Jens Axboe <axboe@xxxxxxxxx>
Stable-dep-of: 457ef47c08d2 ("block: retry call probe after request_module in blk_request_module")
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
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@xxxxxxxxxxxxxxx.
+
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
