On Mon, Mar 03, 2025 at 06:06:36PM +0100, Mikulas Patocka wrote: > The dm-loop driver does the same thing as swapfile activation - so I > presume that if swapfile activation is correct, then dm-loop is also > correct. > > The S_SWAPFILE flag prevents the kernel from truncating, extending or > deleting the file - it just returns "Text file busy". Right: that was the idea, and it was lifted wholesale from swapfile.c. In my testing it seemed reliable, but we had reports from users of very occasional memory or file corruption iirc that we were never able to pin down and resolve. One user in the UK was running it in production for a couple of years on multiple systems - in that time they had a handful of crashes that we were never able to make much sense of. Regards, Bryn.
