Re: [PATCH] swapfile: disable swapon for bs > ps devices

[Christian Brauner <brauner@kernel.org>]

On Fri, May 02, 2025 at 04:13:09PM -0700, Luis Chamberlain wrote:
> Devices which have a requirement for bs > ps cannot be supported for
> swap as swap still needs work. Now that the block device cache sets the
> min order for block devices we need this stop gap otherwise all
> swap operations are rejected.
> 
> Without this you'll end up with errors on these devices as the swap
> code still needs much love to support min order.
> 
> # cat /sys/block/nvme3n1/queue/logical_block_size  16384
> # mkswap /dev/nvme3n1
> mkswap: /dev/nvme3n1: warning: wiping old swap signature.
> Setting up swapspace version 1, size = 100 GiB (107374178304 bytes)
> no label, UUID=6af76b5c-7e7b-4902-b7f7-4c24dde6fa36
> # swapon /dev/nvme3n1
> swapon: /dev/nvme3n1: swapon failed: Invalid argument
> 
> Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
> ---
> 
> I had posted an RFC about a heads up about us needing this less than a year
> ago [0] and well, we now need it for v6.15 since swap code is just not ready.
> 
> Christian, this should probably go through your tree.
> 
> I tested it on a LBS device where the logical block size is 16 KiB on
> x86_64 and confirm that while mkswap would swapon would be rejected.
> 
> [0] https://lore.kernel.org/all/20240627000924.2074949-1-mcgrof@kernel.org/T/#u

Thanks Luis! Did you plan on adding the comment that Christoph requested?