On 2019-08-09, Peter Zijlstra <pet...@infradead.org> wrote: >> End result: a DRAM buffer can work, but is not "reliable". >> Particularly if you turn power on and off, data retention of DRAM is >> iffy. But it's possible, at least in theory. >> >> So I have a patch that implements a "stupid ring buffer" for thisa >> case, with absolutely zero data structures (because in the presense of >> DRAM corruption, all you can get is "hopefully only slightly garbled >> ASCII". > > Note that you can hook this into printk as a fake early serial device; > just have the serial device write to the DRAM buffer.
Or the other way around, implement a fake console to handle writing the messages (as they are being emitted from printk) to some special area. Then the messages would even be pre-processed so that all meta-data is already in ASCII form. John Ogness