linux/drivers/xen
Jan Beulich 27e0e63853 xen/evtchn: fix ring resize when binding new events
The copying of ring data was wrong for two cases: For a full ring
nothing got copied at all (as in that case the canonicalized producer
and consumer indexes are identical). And in case one or both of the
canonicalized (after the resize) indexes would point into the second
half of the buffer, the copied data ended up in the wrong (free) part
of the new buffer. In both cases uninitialized data would get passed
back to the caller.

Fix this by simply copying the old ring contents twice: Once to the
low half of the new buffer, and a second time to the high half.

This addresses the inability to boot a HVM guest with 64 or more
vCPUs.  This regression was caused by 8620015499 (xen/evtchn:
dynamically grow pending event channel ring).

Reported-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Cc: <stable@vger.kernel.org> # 4.4+
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2016-05-04 16:37:01 +01:00
..
events xen/events: Mask a moving irq 2016-04-04 11:18:00 +01:00
xen-pciback
xenbus
xenfs
Kconfig
Makefile
acpi.c
balloon.c xen/balloon: Fix crash when ballooning on x86 32 bit PAE 2016-04-06 11:29:18 +01:00
biomerge.c
cpu_hotplug.c
dbgp.c
efi.c
evtchn.c xen/evtchn: fix ring resize when binding new events 2016-05-04 16:37:01 +01:00
fallback.c
features.c
gntalloc.c
gntdev.c
grant-table.c
manage.c
mcelog.c
pci.c
pcpu.c
platform-pci.c
preempt.c
privcmd.c
privcmd.h
swiotlb-xen.c
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-scsiback.c
xen-selfballoon.c
xen-stub.c
xlate_mmu.c