On 2021/09/28 7:03, Luis Chamberlain wrote:
> diff --git a/drivers/block/ataflop.c b/drivers/block/ataflop.c
> index 5dc9b3d32415..be0627345b21 100644
> --- a/drivers/block/ataflop.c
> +++ b/drivers/block/ataflop.c
> @@ -1989,24 +1989,34 @@ static int ataflop_alloc_disk(unsigned int drive, unsigned int type)
>
> static DEFINE_MUTEX(ataflop_probe_lock);
>
> -static void ataflop_probe(dev_t dev)
> +static int ataflop_probe(dev_t dev)
> {
> int drive = MINOR(dev) & 3;
> int type = MINOR(dev) >> 2;
> + int err = 0;
>
> if (type)
> type--;
>
> - if (drive >= FD_MAX_UNITS || type >= NUM_DISK_MINORS)
> - return;
> + if (drive >= FD_MAX_UNITS || type >= NUM_DISK_MINORS) {
> + err = -EINVAL;
> + goto out;
> + }
> +
> mutex_lock(&ataflop_probe_lock);
> if (!unit[drive].disk[type]) {
> - if (ataflop_alloc_disk(drive, type) == 0) {
> - add_disk(unit[drive].disk[type]);
> + err = ataflop_alloc_disk(drive, type);
> + if (err == 0) {
> + err = add_disk(unit[drive].disk[type]);
> + if (err)
> + blk_cleanup_disk(unit[drive].disk[type]);
> unit[drive].registered[type] = true;
Why setting registered to true despite add_disk() failed?
del_gendisk() without successful add_disk() sounds wrong.
Don't we need to undo ataflop_alloc_disk() because it sets
unit[drive].disk[type] to non-NULL ?
> }
> }
> mutex_unlock(&ataflop_probe_lock);
> +
> +out:
> + return err;
> }
>
> static void atari_cleanup_floppy_disk(struct atari_floppy_struct *fs)
> diff --git a/drivers/block/brd.c b/drivers/block/brd.c
> index c2bf4946f4e3..82a93044de95 100644
> --- a/drivers/block/brd.c
> +++ b/drivers/block/brd.c
> @@ -426,10 +426,11 @@ static int brd_alloc(int i)
> return err;
> }
>
> -static void brd_probe(dev_t dev)
> +static int brd_probe(dev_t dev)
> {
> int i = MINOR(dev) / max_part;
> struct brd_device *brd;
> + int err = 0;
>
> mutex_lock(&brd_devices_mutex);
> list_for_each_entry(brd, &brd_devices, brd_list) {
> @@ -437,9 +438,11 @@ static void brd_probe(dev_t dev)
> goto out_unlock;
> }
>
> - brd_alloc(i);
> + err = brd_alloc(i);
> out_unlock:
> mutex_unlock(&brd_devices_mutex);
> +
> + return err;
> }
>
> static void brd_del_one(struct brd_device *brd)
https://lkml.kernel.org/r/e205f13d-18ff-a49c-0988-7de6ea5ff823@xxxxxxxxxxxxxxxxxxx
will require this part to be updated.
> diff --git a/drivers/block/floppy.c b/drivers/block/floppy.c
> index 0434f28742e7..95a1c8ef62f7 100644
> --- a/drivers/block/floppy.c
> +++ b/drivers/block/floppy.c
> @@ -4517,21 +4517,27 @@ static int floppy_alloc_disk(unsigned int drive, unsigned int type)
>
> static DEFINE_MUTEX(floppy_probe_lock);
>
> -static void floppy_probe(dev_t dev)
> +static int floppy_probe(dev_t dev)
> {
> unsigned int drive = (MINOR(dev) & 3) | ((MINOR(dev) & 0x80) >> 5);
> unsigned int type = (MINOR(dev) >> 2) & 0x1f;
> + int err = 0;
>
> if (drive >= N_DRIVE || !floppy_available(drive) ||
> type >= ARRAY_SIZE(floppy_type))
> - return;
> + return -EINVAL;
>
> mutex_lock(&floppy_probe_lock);
> if (!disks[drive][type]) {
> - if (floppy_alloc_disk(drive, type) == 0)
> - add_disk(disks[drive][type]);
> + if (floppy_alloc_disk(drive, type) == 0) {
> + err = add_disk(disks[drive][type]);
> + if (err)
> + blk_cleanup_disk(disks[drive][type]);
This makes future floppy_probe() no-op once add_disk() failed (or maybe a bad
thing happens somewhere else), for disks[drive][type] was set to non-NULL by
floppy_alloc_disk() but blk_cleanup_disk() does not reset it to NULL.
According to floppy_module_exit() which tries to cleanup it, implementing
undo might be complicated...
> + }
> }
> mutex_unlock(&floppy_probe_lock);
> +
> + return err;
> }
>
> static int __init do_floppy_init(void)
