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| author | Brian Norris <computersforpeace@gmail.com> | 2015-06-01 16:17:20 -0700 |
|---|---|---|
| committer | Brian Norris <computersforpeace@gmail.com> | 2015-10-26 14:34:07 -0700 |
| commit | be0dbff8b46d69bd738f63b4fe0cf64417f776b0 (patch) | |
| tree | 044a2240eba4a10e2a8d920ecd2119e19d84b3de /drivers/mtd/mtdcore.c | |
| parent | 3e00ed0e984bbec47f5e531bad3cf36885aa5d83 (diff) | |
| download | linux-0-day-be0dbff8b46d69bd738f63b4fe0cf64417f776b0.tar.gz linux-0-day-be0dbff8b46d69bd738f63b4fe0cf64417f776b0.tar.xz | |
mtd: warn when registering the same master many times
When CONFIG_MTD_PARTITIONED_MASTER=y, it is fatal to call
mtd_device_parse_register() twice on the same MTD, as we try to register
the same device/kobject multipile times.
When CONFIG_MTD_PARTITIONED_MASTER=n, calling
mtd_device_parse_register() is more of just a nuisance, as we can mostly
navigate around any conflicting actions.
But anyway, doing so is a Bad Thing (TM), and we should complain loudly
for any drivers that try to do this.
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Reviewed-by: Richard Weinberger <richard@nod.at>
Diffstat (limited to 'drivers/mtd/mtdcore.c')
| -rw-r--r-- | drivers/mtd/mtdcore.c | 9 |
1 files changed, 9 insertions, 0 deletions
diff --git a/drivers/mtd/mtdcore.c b/drivers/mtd/mtdcore.c index a2e76ac9f1dcb..41dc501cb49ae 100644 --- a/drivers/mtd/mtdcore.c +++ b/drivers/mtd/mtdcore.c @@ -387,6 +387,14 @@ int add_mtd_device(struct mtd_info *mtd) struct mtd_notifier *not; int i, error; + /* + * May occur, for instance, on buggy drivers which call + * mtd_device_parse_register() multiple times on the same master MTD, + * especially with CONFIG_MTD_PARTITIONED_MASTER=y. + */ + if (WARN_ONCE(mtd->backing_dev_info, "MTD already registered\n")) + return -EEXIST; + mtd->backing_dev_info = &mtd_bdi; BUG_ON(mtd->writesize == 0); @@ -606,6 +614,7 @@ int mtd_device_parse_register(struct mtd_info *mtd, const char * const *types, * does cause problems with parse_mtd_partitions() above (e.g., * cmdlineparts will register partitions more than once). */ + WARN_ONCE(mtd->reboot_notifier.notifier_call, "MTD already registered\n"); if (mtd->_reboot && !mtd->reboot_notifier.notifier_call) { mtd->reboot_notifier.notifier_call = mtd_reboot_notifier; register_reboot_notifier(&mtd->reboot_notifier); |