On Wed, Oct 2, 2019 at 4:49 PM Vishal Verma <[email protected]> wrote: > > Move the note about potential races in memory onlining into the > 'Description' section to make it more prominent. Reword the note to talk > about the sources of such races, and talk about the new 'race detection' > semantics in daxctl. > > Link: https://github.com/pmem/ndctl/issues/110 > Reported-by: Ben Olson <[email protected]> > Cc: Dan Williams <[email protected]> > Signed-off-by: Vishal Verma <[email protected]> > --- > .../daxctl/daxctl-reconfigure-device.txt | 24 +++++++++++-------- > 1 file changed, 14 insertions(+), 10 deletions(-) > > diff --git a/Documentation/daxctl/daxctl-reconfigure-device.txt > b/Documentation/daxctl/daxctl-reconfigure-device.txt > index 196d692..4663529 100644 > --- a/Documentation/daxctl/daxctl-reconfigure-device.txt > +++ b/Documentation/daxctl/daxctl-reconfigure-device.txt > @@ -97,6 +97,20 @@ error reconfiguring devices: Operation not supported > reconfigured 0 devices > ---- > > +'daxctl-reconfigure-device' nominally expects that it will online new memory > +blocks as 'movable', so that kernel data doesn't make it into this memory. > +However, there are other potential agents that may be configured to > +automatically online new hot-plugged memory as it appears. Most notably, > +these are the '/sys/devices/system/memory/auto_online_blocks' configuration, > +or system udev rules. If such an agent races to online memory sections, > daxctl > +checks if the blocks were onlined as 'movable' memory. If this was not the > +case, and the memory blocks are found to be in a different zone, then a > +warning is displayed. If it is desired that a different agent control the > +onlining of memory blocks, and the associated memory zone, then it is > +recommended to use the --no-online option described below. This will abridge > +the device reconfiguration operation to just hotplugging the memory, and > +refrain from then onlining it.
Oh here's that full description that calls out udev. I think just "See daxctl reconfigure-device --help" is sufficient for those warnings in the previous patch. _______________________________________________ Linux-nvdimm mailing list -- [email protected] To unsubscribe send an email to [email protected]
