Re: [PATCH] drm/virtio: Use vmalloc for command buffer allocations.
From: Gerd Hoffmann
Date: Mon Sep 02 2019 - 01:19:46 EST
> > Completely different approach: use get_user_pages() and don't copy the
> > execbuffer at all.
> It would be really nice if execbuffer does not copy.
>
> The user space owns the buffer and may overwrite the contents
> immediately after the ioctl.
Oh, right. The exec ioctl doesn't block. So this doesn't work (breaks
userspace abi). Scratch the idea then.
> We also need a flag to indicate that the
> ownership of the buffer is transferred to the kernel.
Yes, with an additional flag for the changed behavior it could work.
cheers,
Gerd