Re: [Xen-devel] [PATCH v2] x86/shadow: Correct guest behaviour when creating PTEs above maxphysaddr

2017-02-15 Thread George Dunlap
On 14/02/17 17:56, Andrew Cooper wrote: > On 14/02/17 17:49, George Dunlap wrote: >> On 14/02/17 17:45, Andrew Cooper wrote: >>> On 14/02/17 17:42, George Dunlap wrote: On 13/02/17 11:00, Andrew Cooper wrote: > XSA-173 (c/s 8b1764833) introduces gfn_bits, and an upper limit which >

Re: [Xen-devel] [PATCH v2] x86/shadow: Correct guest behaviour when creating PTEs above maxphysaddr

2017-02-15 Thread Jan Beulich
>>> On 14.02.17 at 17:04, wrote: > On 13/02/17 12:36, Jan Beulich wrote: > On 13.02.17 at 12:00, wrote: >>> @@ -360,6 +361,21 @@ void paging_dump_vcpu_info(struct vcpu *v); >>> int paging_set_allocation(struct domain *d, unsigned int

Re: [Xen-devel] [PATCH v2] x86/shadow: Correct guest behaviour when creating PTEs above maxphysaddr

2017-02-14 Thread George Dunlap
On 14/02/17 17:45, Andrew Cooper wrote: > On 14/02/17 17:42, George Dunlap wrote: >> On 13/02/17 11:00, Andrew Cooper wrote: >>> XSA-173 (c/s 8b1764833) introduces gfn_bits, and an upper limit which might >>> be >>> lower than the real maxphysaddr, to avoid overflowing the superpage shadow >>>

Re: [Xen-devel] [PATCH v2] x86/shadow: Correct guest behaviour when creating PTEs above maxphysaddr

2017-02-14 Thread Andrew Cooper
On 14/02/17 17:49, George Dunlap wrote: > On 14/02/17 17:45, Andrew Cooper wrote: >> On 14/02/17 17:42, George Dunlap wrote: >>> On 13/02/17 11:00, Andrew Cooper wrote: XSA-173 (c/s 8b1764833) introduces gfn_bits, and an upper limit which might be lower than the real maxphysaddr,

Re: [Xen-devel] [PATCH v2] x86/shadow: Correct guest behaviour when creating PTEs above maxphysaddr

2017-02-14 Thread Andrew Cooper
On 14/02/17 17:42, George Dunlap wrote: > On 13/02/17 11:00, Andrew Cooper wrote: >> XSA-173 (c/s 8b1764833) introduces gfn_bits, and an upper limit which might >> be >> lower than the real maxphysaddr, to avoid overflowing the superpage shadow >> backpointer. >> >> However, plenty of hardware

Re: [Xen-devel] [PATCH v2] x86/shadow: Correct guest behaviour when creating PTEs above maxphysaddr

2017-02-14 Thread George Dunlap
On 13/02/17 11:00, Andrew Cooper wrote: > XSA-173 (c/s 8b1764833) introduces gfn_bits, and an upper limit which might be > lower than the real maxphysaddr, to avoid overflowing the superpage shadow > backpointer. > > However, plenty of hardware has a physical address width less that 44 bits, >

Re: [Xen-devel] [PATCH v2] x86/shadow: Correct guest behaviour when creating PTEs above maxphysaddr

2017-02-14 Thread Tim Deegan
At 16:04 + on 14 Feb (1487088291), Andrew Cooper wrote: > Hmm ok. With the other bugfix of not dropping the first line, this hunk > is now simply: > > @@ -504,7 +505,7 @@ void recalculate_cpuid_policy(struct domain *d) > > p->extd.maxphysaddr = min(p->extd.maxphysaddr,

Re: [Xen-devel] [PATCH v2] x86/shadow: Correct guest behaviour when creating PTEs above maxphysaddr

2017-02-14 Thread Andrew Cooper
On 13/02/17 12:36, Jan Beulich wrote: On 13.02.17 at 12:00, wrote: >> @@ -502,11 +503,9 @@ void recalculate_cpuid_policy(struct domain *d) >> >> cpuid_featureset_to_policy(fs, p); >> >> -p->extd.maxphysaddr = min(p->extd.maxphysaddr,

Re: [Xen-devel] [PATCH v2] x86/shadow: Correct guest behaviour when creating PTEs above maxphysaddr

2017-02-13 Thread Jan Beulich
>>> On 13.02.17 at 12:00, wrote: > @@ -502,11 +503,9 @@ void recalculate_cpuid_policy(struct domain *d) > > cpuid_featureset_to_policy(fs, p); > > -p->extd.maxphysaddr = min(p->extd.maxphysaddr, max->extd.maxphysaddr); > p->extd.maxphysaddr =

[Xen-devel] [PATCH v2] x86/shadow: Correct guest behaviour when creating PTEs above maxphysaddr

2017-02-13 Thread Andrew Cooper
XSA-173 (c/s 8b1764833) introduces gfn_bits, and an upper limit which might be lower than the real maxphysaddr, to avoid overflowing the superpage shadow backpointer. However, plenty of hardware has a physical address width less that 44 bits, and the code added in shadow_domain_init() is a