On 9/17/24 5:32 AM, Matthew Wilcox wrote: > On Mon, Sep 16, 2024 at 10:47:10AM +0200, Chris Mason wrote: >> I've got a bunch of assertions around incorrect folio->mapping and I'm >> trying to bash on the ENOMEM for readahead case. There's a GFP_NOWARN >> on those, and our systems do run pretty short on ram, so it feels right >> at least. We'll see. > > I've been running with some variant of this patch the whole way across > the Atlantic, and not hit any problems. But maybe with the right > workload ...? > > There are two things being tested here. One is whether we have a > cross-linked node (ie a node that's in two trees at the same time). > The other is whether the slab allocator is giving us a node that already > contains non-NULL entries. > > If you could throw this on top of your kernel, we might stand a chance > of catching the problem sooner. If it is one of these problems and not > something weirder. > I was able to corrupt the xarray one time, hitting a crash during unmount. It wasn't the xfs filesystem I was actually hammering so I guess that tells us something, but it was after ~3 hours of stress runs, so not really useful. I'll try with your patch as well. -chris