linux_dsm_epyc7002/drivers/xen
Olaf Hering ddacf5ef68 xen/pv-on-hvm kexec: add xs_reset_watches to shutdown watches from old kernel
Add new xs_reset_watches function to shutdown watches from old kernel after
kexec boot.  The old kernel does not unregister all watches in the
shutdown path.  They are still active, the double registration can not
be detected by the new kernel.  When the watches fire, unexpected events
will arrive and the xenwatch thread will crash (jumps to NULL).  An
orderly reboot of a hvm guest will destroy the entire guest with all its
resources (including the watches) before it is rebuilt from scratch, so
the missing unregister is not an issue in that case.

With this change the xenstored is instructed to wipe all active watches
for the guest.  However, a patch for xenstored is required so that it
accepts the XS_RESET_WATCHES request from a client (see changeset
23839:42a45baf037d in xen-unstable.hg). Without the patch for xenstored
the registration of watches will fail and some features of a PVonHVM
guest are not available. The guest is still able to boot, but repeated
kexec boots will fail.

[v5: use xs_single instead of passing a dummy string to xs_talkv]
[v4: ignore -EEXIST in xs_reset_watches]
[v3: use XS_RESET_WATCHES instead of XS_INTRODUCE]
[v2: move all code which deals with XS_INTRODUCE into xs_introduce()
    (based on feedback from Ian Campbell); remove casts from kvec assignment]
Signed-off-by: Olaf Hering <olaf@aepfle.de>
[v1: Redid the git description a bit]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-09-22 16:32:24 -04:00
..
xenbus xen/pv-on-hvm kexec: add xs_reset_watches to shutdown watches from old kernel 2011-09-22 16:32:24 -04:00
xenfs Merge branch 'xen/xenbus' of git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen 2011-01-20 16:37:28 -08:00
balloon.c xen/balloon: Move dec_totalhigh_pages() from __balloon_append() to balloon_append() 2011-03-30 11:54:51 -04:00
biomerge.c xen: define BIOVEC_PHYS_MERGEABLE() 2010-10-18 10:40:28 -04:00
cpu_hotplug.c Merge branch 'linux-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6 2009-12-11 12:18:16 -08:00
events.c xen/pv-on-hvm kexec: rebind virqs to existing eventchannel ports 2011-09-01 11:48:54 -04:00
evtchn.c treewide: remove extra semicolons 2011-04-10 17:01:05 +02:00
features.c xen: clean up asm/xen/hypervisor.h 2008-12-16 21:50:31 +01:00
gntalloc.c xen/gntdev,gntalloc: Remove unneeded VM flags 2011-03-09 22:15:28 -05:00
gntdev.c Merge branches 'stable/backend.base.v3' and 'stable/gntalloc.v7' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen 2011-05-19 16:14:25 -07:00
grant-table.c xen/p2m/m2p/gnttab: Support GNTMAP_host_map in the M2P override. 2011-04-18 11:10:27 -04:00
Kconfig xen: change xen/[gntdev/gntalloc] to default m 2011-02-16 09:30:02 -05:00
Makefile Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/djm/tmem 2011-05-26 10:50:56 -07:00
manage.c PM: Remove sysdev suspend, resume and shutdown operations 2011-05-11 21:37:15 +02:00
pci.c xen: register xen pci notifier 2010-10-27 18:56:07 +01:00
platform-pci.c xen: no need to delay xen_setup_shutdown_event for hvm guests anymore 2011-02-25 16:43:03 +00:00
swiotlb-xen.c Merge branch 'stable/xen-swiotlb.bugfix' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/swiotlb-2.6 2011-06-09 12:52:44 -07:00
sys-hypervisor.c drivers/xen/sys-hypervisor: Cleanup code/data sections definitions 2011-05-19 11:30:41 -04:00
tmem.c xen: cleancache shim to Xen Transcendent Memory 2011-05-26 10:02:21 -06:00
xen-balloon.c xen-balloon: Move core balloon functionality out of module 2011-03-16 10:05:34 -04:00
xencomm.c include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00