Re: [PATCH v2] xfs: Use xarray to track SB UUIDs instead of plain array.

[Lukas Herbolt <lukas@herbolt.com>]

On 2026-02-25 15:33, Christoph Hellwig wrote:
> This doens't apply to current mainline or the XFS tree, as it
> doesn't have the healthmon pointer in the mount structure yet.
> 
>> +/*
>> + * Helper fucntions to store UUID in xarray.
> 
> s/fucntions/functions/
> 
> But I'd just drop the comment.
> 
>> + */
>> +static int
>> +xfs_uuid_insert(
>> +	uuid_t		*uuid,
>> +	unsigned int	*index)
>> +{
>> +	return xa_alloc(&xfs_uuid_table, index, uuid,
>> +			xa_limit_32b, GFP_KERNEL);
>> +}
> 
> ... and open code this in the only caller.
> 
>> +static void
>> +xfs_uuid_delete(
>> +	uuid_t		*uuid,
>> +	unsigned int	index)
>> +{
>> +	ASSERT(uuid_equal(xa_load(&xfs_uuid_table, index), uuid));
>> +	xa_erase(&xfs_uuid_table, index);
>> +}
> 
>>  	mutex_unlock(&xfs_uuid_table_mutex);
> 
> This looks like it should be a lock and not unlock?
> 
>> +	if (unlikely(xfs_uuid_search(uuid))) {
>> +		xfs_warn(mp, "Filesystem has duplicate UUID %pU - can't mount",
>> +				uuid);
>> +		return -EINVAL;
> 
> And this is missing an unlock?
> 
> Just curious how this was tested?  xfs/045 should cover mounting with
> duplicate uuids.

I wrote my own simple test I will also try the xfs/045. As always thanks 
for the
notes, will fix it!.
-- 
-lhe