On Fri, Oct 21, 2016 at 1:48 PM, Laszlo Ersek <lersek@xxxxxxxxxx> wrote: > The virtio-rng backend for hwrng passes the buffer that it receives for > filling to sg_set_buf() directly, in: > > virtio_read() [drivers/char/hw_random/virtio-rng.c] > register_buffer() [drivers/char/hw_random/virtio-rng.c] > sg_init_one() [lib/scatterlist.c] > sg_set_buf() [include/linux/scatterlist.h] > > In turn, the sg_set_buf() function, when built with CONFIG_DEBUG_SG, > actively enforces (justifiedly) that the buffer used within the > scatter-gather list live in physically contiguous memory: > > BUG_ON(!virt_addr_valid(buf)); > > The combination of the above two facts means that whatever calls > virtio_read() -- via the hwrng.read() method -- has to allocate the > recipient buffer in physically contiguous memory. Indeed. This bug should be fixed by: https://git.kernel.org/cgit/linux/kernel/git/herbert/cryptodev-2.6.git/commit/?id=6d4952d9d9d4dc2bb9c0255d95a09405a1e958f7 -- To unsubscribe from this list: send the line "unsubscribe linux-crypto" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
