On Mon, Jun 04 2018 at 7:40pm -0400, Dan Williams <dan.j.williams@xxxxxxxxx> wrote: > On Sun, Jun 3, 2018 at 6:48 PM, Dan Williams <dan.j.williams@xxxxxxxxx> wrote: > > On Sun, Jun 3, 2018 at 5:25 PM, Dave Chinner <david@xxxxxxxxxxxxx> wrote: > >> On Mon, Jun 04, 2018 at 08:20:38AM +1000, Dave Chinner wrote: > >>> On Thu, May 31, 2018 at 09:02:52PM -0700, Dan Williams wrote: > >>> > On Thu, May 31, 2018 at 7:24 PM, Dave Chinner <david@xxxxxxxxxxxxx> wrote: > >>> > > On Thu, May 31, 2018 at 06:57:33PM -0700, Dan Williams wrote: > >>> > >> > FWIW, XFS+DAX used to just work on this setup (I hadn't even > >>> > >> > installed ndctl until this morning!) but after changing the kernel > >>> > >> > it no longer works. That would make it a regression, yes? > >>> > >>> [....] > >>> > >>> > >> I suspect your kernel does not have CONFIG_ZONE_DEVICE enabled which > >>> > >> has the following dependencies: > >>> > >> > >>> > >> depends on MEMORY_HOTPLUG > >>> > >> depends on MEMORY_HOTREMOVE > >>> > >> depends on SPARSEMEM_VMEMMAP > >>> > > > >>> > > Filesystem DAX now has a dependency on memory hotplug? > >>> > >>> [....] > >>> > >>> > > OK, works now I've found the magic config incantantions to turn > >>> > > everything I now need on. > >>> > >>> By enabling these options, my test VM now has a ~30s pause in the > >>> boot very soon after the nvdimm subsystem is initialised. > >>> > >>> [ 1.523718] Serial: 8250/16550 driver, 4 ports, IRQ sharing enabled > >>> [ 1.550353] 00:05: ttyS0 at I/O 0x3f8 (irq = 4, base_baud = 115200) is a 16550A > >>> [ 1.552175] Non-volatile memory driver v1.3 > >>> [ 2.332045] tsc: Refined TSC clocksource calibration: 2199.909 MHz > >>> [ 2.333280] clocksource: tsc: mask: 0xffffffffffffffff max_cycles: 0x1fb5dcd4620, max_idle_ns: 440795264143 ns > >>> [ 37.217453] brd: module loaded > >>> [ 37.225423] loop: module loaded > >>> [ 37.228441] virtio_blk virtio2: [vda] 10485760 512-byte logical blocks (5.37 GB/5.00 GiB) > >>> [ 37.245418] virtio_blk virtio3: [vdb] 146800640 512-byte logical blocks (75.2 GB/70.0 GiB) > >>> [ 37.255794] virtio_blk virtio4: [vdc] 1073741824000 512-byte logical blocks (550 TB/500 TiB) > >>> [ 37.265403] nd_pmem namespace1.0: unable to guarantee persistence of writes > >>> [ 37.265618] nd_pmem namespace0.0: unable to guarantee persistence of writes > >>> > >>> The system does not appear to be consuming CPU, but it is blocking > >>> NMIs so I can't get a CPU trace. For a VM that I rely on booting in > >>> a few seconds because I reboot it tens of times a day, this is a > >>> problem.... > >> > >> And when I turn on KASAN, the kernel fails to boot to a login prompt > >> because: > > > > What's your qemu and kernel command line? I'll take look at this first > > thing tomorrow. > > I was able to reproduce this crash by just turning on KASAN... > investigating. It would still help to have your config for our own > regression testing purposes it makes sense for us to prioritize > "Dave's test config", similar to the priority of not breaking Linus' > laptop. Dave, _this_ is when you know you've arrived! ;)
