On Sat, 9 Mar 2024 12:40:51 -0800 Kees Cook <keesc...@chromium.org> wrote:
> The part I'd like to get wired up sanely is having pstore find the > nvdimm area automatically, but it never quite happened: > https://lore.kernel.org/lkml/CAGXu5jLtmb3qinZnX3rScUJLUFdf+pRDVPjy=cs4kutw9tl...@mail.gmail.com/ The automatic detection is what I'm looking for. > > > Thanks for the info. We use pstore on ChromeOS, but it is currently > > restricted to 1MB which is too small for the tracing buffers. From what > > I understand, it's also in a specific location where there's only 1MB > > available for contiguous memory. > > That's the area that is specifically hardware backed with persistent > RAM. > > > I'm looking at finding a way to get consistent memory outside that > > range. That's what I'll be doing next week ;-) > > > > But this code was just to see if I could get a single contiguous range > > of memory mapped to ftrace, and this patch set does exactly that. > > Well, please take a look at pstore. It should be able to do everything > you mention already; it just needs a way to define multiple regions if > you want to use an area outside of the persistent ram area defined by > Chrome OS's platform driver. I'm not exactly sure how to use pstore here. At boot up I just need some consistent memory reserved for the tracing buffer. It just needs to be the same location at every boot up. I don't need a front end. If you mean a way to access it from user space. The front end is the tracefs directory, as I need all the features that the tracefs directory gives. I'm going to look to see how pstore is set up in ChromeOS and see if I can use whatever it does to allocate another location. -- Steve
