Re: [PATCH v3 06/17] hw/sd/sdcard: Do not store vendor data on block drive (CMD56)

Philippe Mathieu-Daudé <philmd(a)linaro.org&gt; writes: > "General command" (GEN_CMD, CMD56) is described as: > > GEN_CMD is the same as the single block read or write > commands (CMD24 or CMD17). The difference is that [...] > the data block is not a memory payload data but has a > vendor specific format and meaning. > > Thus this block must not be stored overwriting data block > on underlying storage drive. Keep it in a dedicated > 'vendor_data[]' array. > > Signed-off-by: Philippe Mathieu-Daudé <philmd(a)linaro.org&gt; > Tested-by: Cédric Le Goater <clg(a)redhat.com&gt; > --- > RFC: Is it safe to reuse VMSTATE_UNUSED_V() (which happens > to be the same size)? Hi, sorry it took some time to get to this, I had just left for vacation when you first posted.

I think it's ok: { "field": "unused", "version_id": 1, "field_exists": false, "size": 512 }, vs. { "field": "vendor_data", "version_id": 0, "field_exists": false, "num": 512, "size": 1 }, The unused field was introduced in 2016 so there's no chance of migrating a QEMU that old to/from 9.1.