Re: [PATCH 2/2] mm: swap: print starting physical block offset in swapon

[Christoph Hellwig]

On Wed, May 22, 2024 at 07:56:37AM -0700, Darrick J. Wong wrote:
> On Wed, May 22, 2024 at 04:46:58PM +0900, Sukrit Bhatnagar wrote:
> > When a swapfile is created for hibernation purposes, we always need
> > the starting physical block offset, which is usually determined using
> > userspace commands such as filefrag.
> 
> If you always need this value, then shouldn't it be exported via sysfs
> or somewhere so that you can always get to it?  The kernel ringbuffer
> can overwrite log messages, swapfiles can get disabled, etc.

Scraping a block address from anything is just broken.

Wher is the code using this?  It needs a proper kernel interface.

Same about the warning crap in patch 1.