Messages in this thread | | | Date | Thu, 16 Feb 2023 07:38:21 +0100 | From | Greg Kroah-Hartman <> | Subject | Re: [PATCH v10 12/26] gunyah: vm_mgr: Add/remove user memory regions |
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On Tue, Feb 14, 2023 at 01:24:16PM -0800, Elliot Berman wrote: > > When launching a virtual machine, Gunyah userspace allocates memory for > the guest and informs Gunyah about these memory regions through > SET_USER_MEMORY_REGION ioctl.
It also frees memory, see below. Why not document that?
> + case GH_VM_SET_USER_MEM_REGION: { > + struct gh_userspace_memory_region region; > + > + if (copy_from_user(®ion, argp, sizeof(region))) > + return -EFAULT; > + > + /* All other flag bits are reserved for future use */ > + if (region.flags & ~(GH_MEM_ALLOW_READ | GH_MEM_ALLOW_WRITE | GH_MEM_ALLOW_EXEC | > + GH_MEM_LENT)) > + return -EINVAL;
Nice, thanks for validating that.
> + > +
Nit, 2 blank lines are not needed :(
> + if (region.memory_size) > + r = gh_vm_mem_alloc(ghvm, ®ion); > + else > + r = gh_vm_mem_free(ghvm, region.label);
So if you set the size to 0 it is freed? Wouldn't a separate ioctl make more sense? Where is this logic documented to userspace?
thanks,
greg k-h
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