diff options
| author | Matt Lupfer | 2014-02-22 05:37:23 +0100 |
|---|---|---|
| committer | Michael S. Tsirkin | 2014-03-27 16:48:11 +0100 |
| commit | c36ad13fe9ece9a21a8c1dd082473a2b182298ee (patch) | |
| tree | d8cdb0993f0fb271eb5b1a473b911f107768d7bd /qmp-commands.hx | |
| parent | Detect pthread_setname_np at configure time (diff) | |
| download | qemu-c36ad13fe9ece9a21a8c1dd082473a2b182298ee.tar.gz qemu-c36ad13fe9ece9a21a8c1dd082473a2b182298ee.tar.xz qemu-c36ad13fe9ece9a21a8c1dd082473a2b182298ee.zip | |
Don't enable a HPET timer if HPET is disabled
A HPET timer can be started when HPET is not yet
enabled. This will not generate an interrupt
to the guest, but causes problems when HPET is later
enabled.
A timer that is created and expires at least once before
HPET is enabled will have an initialized comparator based
on a hpet_offset of 0 (uninitialized). When HPET is
enabled, hpet_set_timer() is called a second time, which
modifies the timer expiry to a time based on the
difference between current ticks (measured with the
newly initialized hpet_offset) and the timer's
comparator (which was generated before hpet_offset was
initialized). This results in a long period of no HPET
timer ticks.
When this occurs with a CentOS 5.x guest, the guest
may not receive timer interrupts during its narrow
timer check window and panic on boot.
Signed-off-by: Matt Lupfer <mlupfer@ddn.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'qmp-commands.hx')
0 files changed, 0 insertions, 0 deletions