How to cope with hardware-poisoned page-cache pages

I can explain this one from some real-world experience: my system has some borderline RAM which runs fine 99.99999% of the time at its rated top speed under heavy load... which obviously isn't enough. Two times in the past year, the btrfs checksumming code noticed something wrong slightly too late and panic-remounted the rootfs ro.

By then of course, the damage is done and I have to hard reboot and fiddle around with recovery tools from a USB disk. Moving the crash as early as possible would still be data loss, but more importantly it'd prevent garbage data (or worse, fs structures) being written.