| Message ID | 4BAB6BF9.30701@us.ibm.com |
|---|---|
| State | New |
| Headers | show |
On Thu, Mar 25, 2010 at 08:58:17AM -0500, Adam Litke wrote: > Beginning with its introduction, the virtio balloon has had an overflow error > that causes 'info balloon' to misreport the actual memory size when the balloon > itself becomes larger than 4G. Use a cast when converting dev->actual from > pages to kB to prevent overflows. > > Before: > (qemu) info balloon > balloon: actual=5120 > (qemu) balloon 1025 > (qemu) info balloon > balloon: actual=1025 > (qemu) balloon 1024 > (qemu) info balloon > balloon: actual=5120 > > After: > (qemu) info balloon > balloon: actual=5120 > (qemu) balloon 1025 > (qemu) info balloon > balloon: actual=1025 > (qemu) balloon 1024 > (qemu) info balloon > balloon: actual=1024 Thanks, applied. > Signed-off-by: Adam Litke <agl@us.ibm.com> > --- > hw/virtio-balloon.c | 3 ++- > 1 files changed, 2 insertions(+), 1 deletions(-) > > diff --git a/hw/virtio-balloon.c b/hw/virtio-balloon.c > index 086d9d1..6eedab1 100644 > --- a/hw/virtio-balloon.c > +++ b/hw/virtio-balloon.c > @@ -78,7 +78,8 @@ static void stat_put(QDict *dict, const char *label, uint64_t val) > static QObject *get_stats_qobject(VirtIOBalloon *dev) > { > QDict *dict = qdict_new(); > - uint32_t actual = ram_size - (dev->actual << VIRTIO_BALLOON_PFN_SHIFT); > + uint64_t actual = ram_size - ((uint64_t) dev->actual << > + VIRTIO_BALLOON_PFN_SHIFT); > > stat_put(dict, "actual", actual); > stat_put(dict, "mem_swapped_in", dev->stats[VIRTIO_BALLOON_S_SWAP_IN]); > -- > 1.6.3.3 > > > > >
diff --git a/hw/virtio-balloon.c b/hw/virtio-balloon.c index 086d9d1..6eedab1 100644 --- a/hw/virtio-balloon.c +++ b/hw/virtio-balloon.c @@ -78,7 +78,8 @@ static void stat_put(QDict *dict, const char *label, uint64_t val) static QObject *get_stats_qobject(VirtIOBalloon *dev) { QDict *dict = qdict_new(); - uint32_t actual = ram_size - (dev->actual << VIRTIO_BALLOON_PFN_SHIFT); + uint64_t actual = ram_size - ((uint64_t) dev->actual << + VIRTIO_BALLOON_PFN_SHIFT); stat_put(dict, "actual", actual); stat_put(dict, "mem_swapped_in", dev->stats[VIRTIO_BALLOON_S_SWAP_IN]);
Beginning with its introduction, the virtio balloon has had an overflow error that causes 'info balloon' to misreport the actual memory size when the balloon itself becomes larger than 4G. Use a cast when converting dev->actual from pages to kB to prevent overflows. Before: (qemu) info balloon balloon: actual=5120 (qemu) balloon 1025 (qemu) info balloon balloon: actual=1025 (qemu) balloon 1024 (qemu) info balloon balloon: actual=5120 After: (qemu) info balloon balloon: actual=5120 (qemu) balloon 1025 (qemu) info balloon balloon: actual=1025 (qemu) balloon 1024 (qemu) info balloon balloon: actual=1024 Signed-off-by: Adam Litke <agl@us.ibm.com> --- hw/virtio-balloon.c | 3 ++- 1 files changed, 2 insertions(+), 1 deletions(-)