Messages in this thread | | | Subject | Re: [PATCH v2] xen: add new hypercall buffer mapping device | From | Boris Ostrovsky <> | Date | Mon, 18 Jun 2018 11:27:05 -0400 |
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On 06/18/2018 03:36 AM, Juergen Gross wrote: > For passing arbitrary data from user land to the Xen hypervisor the > Xen tools today are using mlock()ed buffers. Unfortunately the kernel > might change access rights of such buffers for brief periods of time > e.g. for page migration or compaction, leading to access faults in the > hypervisor, as the hypervisor can't use the locks of the kernel. > > In order to solve this problem add a new device node to the Xen privcmd > driver to easily allocate hypercall buffers via mmap(). The memory is > allocated in the kernel and just mapped into user space. Marked as > VM_IO the user mapping will not be subject to page migration et al. > > Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
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