Re: [Qemu-devel] [PATCH 1/6] Terminate emulation on memory allocation failure

[Daniel P. Berrange]

On Thu, Feb 05, 2009 at 01:08:41PM +0200, Avi Kivity wrote:
> Memory allocation failures are a very rare condition on virtual-memory
> hosts.  They are also very difficult to handle correctly (especially in a
> hardware emulation context).  Because of this, it is better to gracefully
> terminate emulation rather than executing untested or even unwritten recovery
> code paths.
> 
> This patch changes the qemu memory allocation routines to terminate emulation
> if an allocation failure is encountered.
> 
> Signed-off-by: Avi Kivity <address@hidden>
> ---
>  qemu-malloc.c |   16 ++++++++++------
>  1 files changed, 10 insertions(+), 6 deletions(-)
> 
> diff --git a/qemu-malloc.c b/qemu-malloc.c
> index dc74efe..1d00f26 100644
> --- a/qemu-malloc.c
> +++ b/qemu-malloc.c
> @@ -22,6 +22,14 @@
>   * THE SOFTWARE.
>   */
>  #include "qemu-common.h"
> +#include <stdlib.h>
> +
> +static void *oom_check(void *ptr)
> +{
> +    if (ptr == NULL)
> +        exit(13);
> +    return ptr;
> +}

Will all our atexit handlers cope with OOM too? In particular
we don't want them calling qemu_malloc again, or this becomes
re-entrant. If we want to go down this route, then abort() is
probably safer.

Daniel
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