On Mon, Jan 21, 2019 at 03:48:40PM +0300, Alexander Popov wrote:
> The single-step debugging of KVM guests on x86 is broken: if we run
> gdb 'stepi' command at the breakpoint when the guest interrupts are
> enabled, RIP always jumps to native_apic_mem_write(). Then other
> nasty effects follow.
>
> Long investigation showed that on Jun 7, 2017 the
> commit c8401dda2f0a00cd25c0 ("KVM: x86: fix singlestepping over syscall")
> introduced the kvm_run.debug corruption: kvm_vcpu_do_singlestep() can
> be called without X86_EFLAGS_TF set.
>
> Let's fix it. Please consider that for -stable.
>
> Signed-off-by: Alexander Popov <alex.popov@xxxxxxxxx>
> ---
> arch/x86/kvm/x86.c | 3 +--
> 1 file changed, 1 insertion(+), 2 deletions(-)
<formletter>
This is not the correct way to submit patches for inclusion in the
stable kernel tree. Please read:
https://www.kernel.org/doc/html/latest/process/stable-kernel-rules.html
for how to do this properly.
</formletter>
