Re: include/linux/kvm_host.h:488 suspicious rcu_dereference_check() usage!

2015-09-21 Thread Borislav Petkov
On Mon, Sep 21, 2015 at 05:19:57PM +0200, Paolo Bonzini wrote: > First, the leaf test would have to be == 0, because I prepared the > patch on the first 4.3 pull request instead of the latest Linus > tree. However even this would not be a good change, because > > is_shadow_present_pte(spte) == !(

Re: include/linux/kvm_host.h:488 suspicious rcu_dereference_check() usage!

2015-09-21 Thread Paolo Bonzini
On 21/09/2015 17:10, Paolo Bonzini wrote: > > > On 20/09/2015 18:48, Borislav Petkov wrote: >> [26421.593927] -- spte 0x3e5a22027 level 4. >> [26421.598228] -- spte 0x38a00b027 level 3. >> [26421.602505] -- spte 0x387334027 level 2. >> [26421.602506] -- spte 0x000b8f67 l

Re: include/linux/kvm_host.h:488 suspicious rcu_dereference_check() usage!

2015-09-21 Thread Paolo Bonzini
On 20/09/2015 18:48, Borislav Petkov wrote: > [26421.593927] -- spte 0x3e5a22027 level 4. > [26421.598228] -- spte 0x38a00b027 level 3. > [26421.602505] -- spte 0x387334027 level 2. > [26421.602506] -- spte 0x000b8f67 level 1. > [26421.602506] [ cut here ]-

Re: include/linux/kvm_host.h:488 suspicious rcu_dereference_check() usage!

2015-09-20 Thread Paolo Bonzini
On 20/09/2015 18:48, Borislav Petkov wrote: > [26421.584526] walk_shadow_page_get_mmio_spte: detect reserved bits on spte, > addr 0xb8000, dump hierarchy: > [26421.593927] -- spte 0x3e5a22027 level 4. > [26421.598228] -- spte 0x38a00b027 level 3. > [26421.602505] -- spte 0x387334027

include/linux/kvm_host.h:488 suspicious rcu_dereference_check() usage!

2015-09-20 Thread Borislav Petkov
Hey Paolo, just triggered this on rc1+tip with a 32-bit guest: [26421.303750] === [26421.307952] [ INFO: suspicious RCU usage. ] [26421.312161] 4.3.0-rc1+ #1 Not tainted [26421.312161] --- [26421.312162] include/linux/kvm_host.h:488