> > How about this patch? It tries to solve this race without additional > > locking. If refcount is already zero, it will increment and decrement > > it. So be careful to only call grab_namespace() with vfsmount_lock > > held, otherwise it could race with itself. (vfsmount_lock is also > > needed in this case so that mnt->mnt_namespace, doesn't change, while > > grabbing the namespace) > > How about using cmpxchg? How? If the count is nonzero, an incremented count must be stored. You can't do that atomically with cmpxchg. Miklos - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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- [PATCH] fix race in mark_mounts_for_expiry()
- From: Miklos Szeredi <[email protected]>
- Re: [PATCH] namespace.c: fix bind mount from foreign namespace
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- Re: [PATCH] namespace.c: fix bind mount from foreign namespace
- From: Miklos Szeredi <[email protected]>
- Re: [PATCH] namespace.c: fix bind mount from foreign namespace
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- Re: [PATCH] namespace.c: fix bind mount from foreign namespace
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- Re: [PATCH] namespace.c: fix bind mount from foreign namespace
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- Re: [PATCH] namespace.c: fix bind mount from foreign namespace
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- Re: [PATCH] namespace.c: fix bind mount from foreign namespace
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