Re: [e2fsprogs PATCH] resize2fs: use directio when reading superblock

[Krister Johansen <kjlx@templeofstupid.com>]

On Wed, Jun 07, 2023 at 09:39:09AM -0400, Theodore Ts'o wrote:
> On Mon, Jun 05, 2023 at 03:52:21PM -0700, Krister Johansen wrote:
> > Invocations of resize2fs intermittently report failure due to superblock
> > checksum mismatches in this author's environment.  This might happen a few
> > times a week.  The following script can make this happen within minutes.
> > (It assumes /dev/nvme1n1 is available and not in use by anything else).
> 
> What version of e2fsprogs are you using, and what is your environment?

I hit this originally using e2fsprogs 1.45.5.  That didn't have your
patch for retrying the superblock read on checksum failure.  I pulled
that patch in initially, but it did not fully resolve the checksum
mismatch error.  The test provided in the report was using an EBS volume
attached to an EC2 instance.  (Let me know what additional environment
details would be useful, if these are not).

> Are you perhaps trying to change the UUID of the file system (for
> example, in a cloud image environment) in parallel with resizing the
> file system to fit the size of the block device?

The growpart / resize2fs in the reproducer are essentially verbatim from
our system provisioning scripts.  Unless those modify the UUID, we're
not taking any explicit action to do so.

Thanks,

-K