On 09.11.21 04:59, Dave Young wrote: > Hi Andrew, > On 11/08/21 at 06:31pm, Andrew Morton wrote: >> From: David Hildenbrand <david@xxxxxxxxxx> >> Subject: proc/vmcore: convert oldmem_pfn_is_ram callback to more generic vmcore callbacks >> >> Let's support multiple registered callbacks, making sure that registering >> vmcore callbacks cannot fail. Make the callback return a bool instead of >> an int, handling how to deal with errors internally. Drop unused >> HAVE_OLDMEM_PFN_IS_RAM. >> >> We soon want to make use of this infrastructure from other drivers: >> virtio-mem, registering one callback for each virtio-mem device, to >> prevent reading unplugged virtio-mem memory. >> >> Handle it via a generic vmcore_cb structure, prepared for future >> extensions: for example, once we support virtio-mem on s390x where the >> vmcore is completely constructed in the second kernel, we want to detect >> and add plugged virtio-mem memory ranges to the vmcore in order for them >> to get dumped properly. >> >> Handle corner cases that are unexpected and shouldn't happen in sane >> setups: registering a callback after the vmcore has already been opened >> (warn only) and unregistering a callback after the vmcore has already been >> opened (warn and essentially read only zeroes from that point on). > > This is a nice improvement, thanks David. But I did not get time to > review it yet. The overall idea is good, I would prefer to hold on the > patches for some time and waiting for more review. > > Sorry for jumping in late. I really want this in v5.16. Please see the comment in https://lkml.kernel.org/r/20211006122709.27885-1-david@xxxxxxxxxx Can we just fix any fallout (if any) as usual after the merge window? -- Thanks, David / dhildenb
