On Wed, Mar 29, 2017 at 11:04:39PM +0200, Iwona Kotlarska wrote:
> Running QEMU with "qemu-system-x86_64 -M none -nographic -m 256" and executing
> "dump-guest-memory /dev/null 0 8192" results in segfault.
> Fix by checking if we have CPU.
>
> Signed-off-by: Iwona Kotlarska <iwona260909@gmail.com>
> ---
> v1 --> v2
> Added brackets around if body.
> Changed subject.
> target/i386/arch_dump.c | 8 +++++---
> 1 file changed, 5 insertions(+), 3 deletions(-)
>
> diff --git a/target/i386/arch_dump.c b/target/i386/arch_dump.c
> index 5a2e4be5d0..43992a440c 100644
> --- a/target/i386/arch_dump.c
> +++ b/target/i386/arch_dump.c
> @@ -390,9 +390,11 @@ int cpu_get_dump_info(ArchDumpInfo *info,
> GuestPhysBlock *block;
>
> #ifdef TARGET_X86_64
[Reordering the diff a little bit to make my comments clearer]
> - X86CPU *first_x86_cpu = X86_CPU(first_cpu);
> + X86CPU *first_x86_cpu = NULL;
> + first_x86_cpu = X86_CPU(first_cpu);
There's no reason to replace that single line with these ones.
> -
> - lma = !!(first_x86_cpu->env.hflags & HF_LMA_MASK);
> + if (first_cpu != NULL) {
> + lma = !!(first_x86_cpu->env.hflags & HF_LMA_MASK);
> + }
This part looks OK, although personally I would prefer to write it as:
lma = first_cpu && (first_x86_cpu->env.hflags & HF_LMA_MASK);
so this can become a single-line patch.
I also wonder if the TARGET_X86_64 #ifdef is really necessary. Is
it possible to ever have HF_LMA_MASK set if the target is not
x86_64? But that's something for a separate patch, and unrelated
to the bug you are fixing.
> #endif
>
> if (lma) {
> --
> 2.12.0
>
--
Eduardo