Re: [PATCH] Re: filesystem being remounted supports timestamps until 2038

From: Christian Kujau
Date: Sat Jan 04 2020 - 18:52:22 EST


On Sun, 29 Dec 2019, Linus Torvalds wrote:
> > When file systems are remounted a couple of times per day (e.g. rw/ro for backup
> > purposes), dmesg gets flooded with these messages. Change pr_warn into pr_debug
> > to make it stop.
>
> How about just doing it once per mount?

Yes, once per mount would work, and maybe not print a warning on remounts
at all.

Commit f8b92ba67c5d ("mount: Add mount warning for impending timestamp
expiry") introduced:

Mounted %s file system at %s supports timestamps until [...]

in mnt_warn_timestamp_expiry(), but then 0ecee6699064 ("fs/namespace.c:
fix use-after-free of mount in mnt_warn_timestamp_expiry") changed this to

%s filesystem being %s at %s supports timestamps until [...]

in order to fix a use-after-free.

> Of course, if you actually unmount and completely re-mount a
> filesystem, then that would still warn multiple times, but at that
> point I think it's reasonable to do.

Yes, of course. Umount/remount cycles should still issue a warning, but
"-o remount" should not, IMHO.

Thanks,
Christian.
--
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The air conditioning water supply pipe ruptured over the machine room