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Von: "chengzhihao1" chengzhihao1@huawei.com
Hi Greg, hi patch-developers,
wait a second. this already went into v5.4.268 but still: Doesn't this break userspace?
According to https://lore.kernel.org/lkml/441107100.23734.1697904580252.JavaMail.zimbra@n... where this solution seems to come from, the behaviour changes: "no mtdblock (hence, also no FTLs) on top of gluebi."
I fell accross this because of an out-of-tree module that does sys_mount() an mtdblock, so I won't complain about my code specifically :) But doesn't it break mounting, say, jffs2 inside an ubi via mtdblock? If so, is this really something that you want to see backported to old kernels?
Or differently put: Has this patch been picked up for old stable kernels by scripts or by a human?
I just want to make sure, and who knows, it might help others too, who would just do a (possibly dangerous?) revert in their trees.
This change does affect the mounting(mtdblock based on gluebi) behavior in userspace. It was picked into stable versions because the fixed problem is serious and easy to be reproduced, I guess. A temporary solution is that modify mounting source target in userspace, just replace mtdblock with mtd char device. For example, mount -t jffs2 mtd0 /mnt
I don't think this needs backporting to stable. It's not serious because you still need to be root to setup and trigger such a scenario.
Thanks, //richard