Re: use tasklet to handle init/sipi?

[Keir Fraser <keir.xen@gmail.com>]

There are deadlock issues around directly locking and resetting a remote
vcpu (e.g., buggy/malicious guest vcpu A sends INIT to vcpu B, and B does
same to A).

 -- Keir

On 25/03/2013 05:31, "Zhang, Yang Z" <yang.z.zhang@intel.com> wrote:

> Hi, Keir,
> 
> I am looking into a issue and found cs:17457 changes to use tasklet to handle
> init and sipi. And the comments only said "clean up". I wonder is there any
> special reason to use tasklet to handle it? If no, I will send a patch to call
> handler directly instead via tasklet.
> The background is that with APICv, it assume all apic write is succeed and
> don't care the return value of vlapic_reg_write(). But the above logic need
> the caller to check return value. This obviously will break APICv.
> 
> # HG changeset patch
> # User Keir Fraser <keir.fraser@citrix.com>
> # Date 1208270873 -3600
> # Node ID e15be54059e4bde8f5916269dedff5fc3812686a
> # Parent  6691ae150d104127c097fd9f3a6acccc5ce43c52
> x86, hvm: Clean up handling of APIC INIT and SIPI messages.
> Signed-off-by: Keir Fraser <keir.fraser@citrix.com>
> 
> best regards
> yang
>