linux/drivers/xen
David Hildenbrand 0266def913 xen/balloon: Fix mapping PG_offline pages to user space
The XEN balloon driver - in contrast to other balloon drivers - allows
to map some inflated pages to user space. Such pages are allocated via
alloc_xenballooned_pages() and freed via free_xenballooned_pages().
The pfn space of these allocated pages is used to map other things
by the hypervisor using hypercalls.

Pages marked with PG_offline must never be mapped to user space (as
this page type uses the mapcount field of struct pages).

So what we can do is, clear/set PG_offline when allocating/freeing an
inflated pages. This way, most inflated pages can be excluded by
dumping tools and the "reused for other purpose" balloon pages are
correctly not marked as PG_offline.

Fixes: 77c4adf6a6 (xen/balloon: mark inflated pages PG_offline)
Reported-by: Julien Grall <julien.grall@arm.com>
Tested-by: Julien Grall <julien.grall@arm.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
2019-03-15 15:35:35 +01:00
..
events
xen-pciback
xenbus
xenfs
acpi.c
arm-device.c
balloon.c xen/balloon: Fix mapping PG_offline pages to user space 2019-03-15 15:35:35 +01:00
biomerge.c
cpu_hotplug.c
dbgp.c
efi.c
evtchn.c
features.c
gntalloc.c
gntdev-common.h
gntdev-dmabuf.c
gntdev-dmabuf.h
gntdev.c
grant-table.c
Kconfig
Makefile
manage.c
mcelog.c
mem-reservation.c
pci.c
pcpu.c
platform-pci.c
preempt.c
privcmd-buf.c
privcmd.c
privcmd.h
pvcalls-back.c
pvcalls-front.c
pvcalls-front.h
swiotlb-xen.c treewide: add checks for the return value of memblock_alloc*() 2019-03-12 10:04:02 -07:00
sys-hypervisor.c
time.c
tmem.c
xen-acpi-cpuhotplug.c
xen-acpi-memhotplug.c
xen-acpi-pad.c
xen-acpi-processor.c
xen-balloon.c
xen-front-pgdir-shbuf.c
xen-scsiback.c
xen-selfballoon.c
xen-stub.c
xlate_mmu.c