linux/include/uapi
David Woodhouse d8ba8ba4c8 KVM: x86/xen: Allow XEN_RUNSTATE_UPDATE flag behaviour to be configured
Closer inspection of the Xen code shows that we aren't supposed to be
using the XEN_RUNSTATE_UPDATE flag unconditionally. It should be
explicitly enabled by guests through the HYPERVISOR_vm_assist hypercall.
If we randomly set the top bit of ->state_entry_time for a guest that
hasn't asked for it and doesn't expect it, that could make the runtimes
fail to add up and confuse the guest. Without the flag it's perfectly
safe for a vCPU to read its own vcpu_runstate_info; just not for one
vCPU to read *another's*.

I briefly pondered adding a word for the whole set of VMASST_TYPE_*
flags but the only one we care about for HVM guests is this, so it
seemed a bit pointless.

Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Message-Id: <20221127122210.248427-3-dwmw2@infradead.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
History 2022-11-30 10:59:37 -05:00
..
asm-generic hugetlb_encode.h: fix undefined behaviour (34 << 26) 2022-10-03 14:02:55 -07:00
drm drm/amd: Add IMU fw version to fw version queries 2022-10-24 14:44:03 -04:00
linux KVM: x86/xen: Allow XEN_RUNSTATE_UPDATE flag behaviour to be configured 2022-11-30 10:59:37 -05:00
misc This update includes the following changes: 2022-10-10 13:04:25 -07:00
mtd This pull request contains updates for UBI and UBIFS 2022-10-14 18:23:23 -07:00
rdma RDMA/rxe: Remove redundant num_sge fields 2022-09-27 10:15:24 -03:00
scsi scsi: scsi_transport_fc: Adjust struct fc_nl_event flex array usage 2022-09-25 12:52:48 -04:00
sound ALSA: Remove some left-over license text in include/uapi/sound/ 2022-09-27 08:42:50 +02:00
video License cleanup: add SPDX license identifier to uapi header files with a license 2017-11-02 11:20:11 +01:00
xen Improve docs for IOCTL_GNTDEV_MAP_GRANT_REF 2022-02-03 08:23:32 +01:00
Kbuild kbuild: re-implement Makefile.headersinst without recursion 2019-06-15 19:57:02 +09:00