Re: [PATCH 2/3] kvm tools: check negative value of num_pages

walimis
2011-08-11T13:53:38Z

On Thu, Aug 11, 2011 at 04:36:29PM +0300, Pekka Enberg wrote:
>On Thu, 11 Aug 2011, Liming Wang wrote:
>>If num_pages is negative, balloon will make kernel crash with
>>"out of memory". So we check this value to avoid it to be negative.
>>
>>Signed-off-by: Liming Wang <walimisdev@gmail.com>
>>---
>>tools/kvm/virtio/balloon.c | 8 ++++++--
>>1 files changed, 6 insertions(+), 2 deletions(-)
>>
>>diff --git a/tools/kvm/virtio/balloon.c b/tools/kvm/virtio/balloon.c
>>index 854d04b..941023e 100644
>>--- a/tools/kvm/virtio/balloon.c
>>+++ b/tools/kvm/virtio/balloon.c
>>@@ -220,10 +220,14 @@ static struct ioport_operations virtio_bln_io_ops = {
>>
>>static void handle_sigmem(int sig)
>>{
>>- if (sig == SIGKVMADDMEM)
>>+ if (sig == SIGKVMADDMEM) {
>> bdev.config.num_pages += 256;
>>- else
>>+ } else {
>>+ if (bdev.config.num_pages < 256){
>
>Space missing before opening brace.
>
>>+ return;
>>+ }
>
>Please don't use braces for single line if statements.
>
>I'll fix it up myself. You can use the scripts/checkpatch script to
>check for this kind of trivial coding style issues before sending a
>patch out.
OK, I will take note next time.

walimis
>
>> bdev.config.num_pages -= 256;
>>+ }
>>
>> /* Notify that the configuration space has changed */
>> bdev.isr = VIRTIO_PCI_ISR_CONFIG;
>>--
>>1.7.0.4
>>
>>