android_kernel_samsung_msm8976/arch
Vitaly Kuznetsov 919845cb33 x86/xen: Support kexec/kdump in HVM guests by doing a soft reset
commit 0b34a166f291d255755be46e43ed5497cdd194f2 upstream.

Currently there is a number of issues preventing PVHVM Xen guests from
doing successful kexec/kdump:

  - Bound event channels.
  - Registered vcpu_info.
  - PIRQ/emuirq mappings.
  - shared_info frame after XENMAPSPACE_shared_info operation.
  - Active grant mappings.

Basically, newly booted kernel stumbles upon already set up Xen
interfaces and there is no way to reestablish them. In Xen-4.7 a new
feature called 'soft reset' is coming. A guest performing kexec/kdump
operation is supposed to call SCHEDOP_shutdown hypercall with
SHUTDOWN_soft_reset reason before jumping to new kernel. Hypervisor
(with some help from toolstack) will do full domain cleanup (but
keeping its memory and vCPU contexts intact) returning the guest to
the state it had when it was first booted and thus allowing it to
start over.

Doing SHUTDOWN_soft_reset on Xen hypervisors which don't support it is
probably OK as by default all unknown shutdown reasons cause domain
destroy with a message in toolstack log: 'Unknown shutdown reason code
5. Destroying domain.'  which gives a clue to what the problem is and
eliminates false expectations.

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-22 14:37:50 -07:00
..
alpha
arc ARC: make sure instruction_pointer() returns unsigned value 2015-08-10 12:20:30 -07:00
arm ARM: 8429/1: disable GCC SRA optimization 2015-10-22 14:37:49 -07:00
arm64 arm64: head.S: initialise mdcr_el2 in el2_setup 2015-10-01 12:07:29 +02:00
avr32
blackfin
c6x
cris
frv
h8300
hexagon
ia64
m32r
m68k
metag
microblaze
mips signal: fix information leak in copy_siginfo_from_user32 2015-08-16 20:51:42 -07:00
mn10300
openrisc
parisc parisc: Filter out spurious interrupts in PA-RISC irq handler 2015-10-01 12:07:32 +02:00
powerpc powerpc/rtas: Introduce rtas_get_sensor_fast() for IRQ handlers 2015-10-01 12:07:30 +02:00
s390 s390/sclp: clear upper register halves in _sclp_print_early 2015-08-10 12:20:29 -07:00
score
sh
sparc sparc64: Fix userspace FPU register corruptions. 2015-08-16 20:51:38 -07:00
tile tile: use free_bootmem_late() for initrd 2015-08-10 12:20:30 -07:00
um
unicore32
x86 x86/xen: Support kexec/kdump in HVM guests by doing a soft reset 2015-10-22 14:37:50 -07:00
xtensa xtensa: don't use echo -e needlessly 2015-09-21 10:00:10 -07:00
.gitignore
Kconfig