From f8479dd6a03cfdc3b14e742045bfd8748cd86bd7 Mon Sep 17 00:00:00 2001 From: Brian Norris Date: Tue, 3 Nov 2015 17:01:53 -0800 Subject: [PATCH] mtd: don't WARN about overloaded users of mtd->reboot_notifier.notifier_call There are multiple types of users of mtd->reboot_notifier.notifier_call: (1) A while back, the cfi_cmdset_000{1,2} chip drivers implemented a reboot notifier to (on a best effort basis) attempt to reset their flash chips before rebooting. (2) More recently, we implemented a common _reboot() hook so that MTD drivers (particularly, NAND flash) could better halt I/O operations without having to reimplement the same notifier boilerplate. Currently, the WARN_ONCE() condition here was written to handle (2), but at the same time it mis-diagnosed case (1) as an already-registered MTD. Let's fix this by having the WARN_ONCE() condition better imitate the condition that immediately follows it. (Wow, I don't know how I missed that one.) (Side note: Unfortunately, we can't yet combine the reboot notifier code for (1) and (2) with a patch like [1], because some users of (1) also use mtdconcat, and so the mtd_info struct from cfi_cmdset_000{1,2} won't actually get registered with mtdcore, and therefore their reboot notifier won't get registered.) [1] http://patchwork.ozlabs.org/patch/417981/ Suggested-by: Guenter Roeck Signed-off-by: Brian Norris Cc: Jesper Nilsson Cc: linux-cris-kernel@axis.com Tested-by: Ezequiel Garcia Tested-by: Guenter Roeck Signed-off-by: Brian Norris --- drivers/mtd/mtdcore.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/mtd/mtdcore.c b/drivers/mtd/mtdcore.c index b1eea48c501d..a91cee90aef9 100644 --- a/drivers/mtd/mtdcore.c +++ b/drivers/mtd/mtdcore.c @@ -616,7 +616,8 @@ 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"); + WARN_ONCE(mtd->_reboot && 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);