On Wed, Nov 05, 2025 at 08:33:10AM -0500, James Bottomley wrote:

On Wed, 2025-11-05 at 14:16 +0100, Christian Brauner wrote:

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On Wed, Nov 05, 2025 at 08:09:03AM -0500, James Bottomley wrote:

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On Wed, 2025-11-05 at 12:47 +0100, Christian Brauner wrote:

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And suspend/resume works just fine with freeze/thaw. See commit
eacfbf74196f ("power: freeze filesystems during suspend/resume")
which implements exactly that.

The reason this didn't work for you is very likely:

cat /sys/power/freeze_filesystems
0

which you must set to 1.

Actually, no, that's not correct.  The efivarfs freeze/thaw logic
must run unconditionally regardless of this setting to fix the
systemd bug, so all the variable resyncing is done in the thaw
call, which isn't conditioned on the above (or at least it
shouldn't be).

It is conditioned on the above currently but we can certainly fix it
easily to not be.

It still seems to be unconditional in upstream 6.18-rc4
kernel/power/hibernate.c with only freeze being conditioned on the

I'm honestly not sure how efivarfs would be frozen if
filesystems_freeze() isn't called... Maybe I missed that memo though.
In any case I just sent you...

setting of the filesystem_freeze variable but I haven't checked -next.

However, if there's anything in the works to change that we would need
an exception for efivarfs, please ... we can't have a bug fix
conditioned on a user setting.

... a patch in another mail.

Sorry in case I misunderstood that you _always_ wanted that sync
regardless of userspace enabling it.