| Message ID | 20201231171021.10361-1-andrew.cooper3@citrix.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | x86/p2m: Fix paging_gva_to_gfn() for nested virt | expand |
On Thu, Dec 31, 2020 at 12:11 PM Andrew Cooper <andrew.cooper3@citrix.com> wrote: > > nestedhap_walk_L1_p2m() takes guest physical addresses, not frame numbers. > This means the l2 input is off-by-PAGE_SHIFT, as is the l1 value eventually > returned to the caller. > > Delete the misleading comment as well. > > Fixes: bab2bd8e222de ("xen/nested_p2m: Don't walk EPT tables with a regular PT walker") > Reported-by: Tamas K Lengyel <tamas@tklengyel.com> > Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com> > --- > CC: Jan Beulich <JBeulich@suse.com> > CC: Roger Pau Monné <roger.pau@citrix.com> > CC: Wei Liu <wl@xen.org> > CC: Tamas K Lengyel <tamas@tklengyel.com> Thanks, issue is resolved with this patch applied. Tested-by: Tamas K Lengyel <tamas@tklengyel.com>
On Thu, Dec 31, 2020 at 05:10:21PM +0000, Andrew Cooper wrote: > nestedhap_walk_L1_p2m() takes guest physical addresses, not frame numbers. > This means the l2 input is off-by-PAGE_SHIFT, as is the l1 value eventually > returned to the caller. > > Delete the misleading comment as well. > > Fixes: bab2bd8e222de ("xen/nested_p2m: Don't walk EPT tables with a regular PT walker") > Reported-by: Tamas K Lengyel <tamas@tklengyel.com> > Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com> Acked-by: Roger Pau Monné <roger.pau@citrix.com> Thanks, Roger.
diff --git a/xen/arch/x86/mm/p2m.c b/xen/arch/x86/mm/p2m.c index 487959b121..89a2b55c66 100644 --- a/xen/arch/x86/mm/p2m.c +++ b/xen/arch/x86/mm/p2m.c @@ -1784,6 +1784,7 @@ unsigned long paging_gva_to_gfn(struct vcpu *v, if ( is_hvm_vcpu(v) && paging_mode_hap(v->domain) && nestedhvm_is_n2(v) ) { unsigned long l2_gfn, l1_gfn; + paddr_t l1_gpa; struct p2m_domain *p2m; const struct paging_mode *mode; uint8_t l1_p2ma; @@ -1798,8 +1799,8 @@ unsigned long paging_gva_to_gfn(struct vcpu *v, if ( l2_gfn == gfn_x(INVALID_GFN) ) return gfn_x(INVALID_GFN); - /* translate l2 guest gfn into l1 guest gfn */ - rv = nestedhap_walk_L1_p2m(v, l2_gfn, &l1_gfn, &l1_page_order, &l1_p2ma, + rv = nestedhap_walk_L1_p2m(v, pfn_to_paddr(l2_gfn), &l1_gpa, + &l1_page_order, &l1_p2ma, 1, !!(*pfec & PFEC_write_access), !!(*pfec & PFEC_insn_fetch)); @@ -1807,6 +1808,8 @@ unsigned long paging_gva_to_gfn(struct vcpu *v, if ( rv != NESTEDHVM_PAGEFAULT_DONE ) return gfn_x(INVALID_GFN); + l1_gfn = paddr_to_pfn(l1_gpa); + /* * Sanity check that l1_gfn can be used properly as a 4K mapping, even * if it mapped by a nested superpage.
nestedhap_walk_L1_p2m() takes guest physical addresses, not frame numbers. This means the l2 input is off-by-PAGE_SHIFT, as is the l1 value eventually returned to the caller. Delete the misleading comment as well. Fixes: bab2bd8e222de ("xen/nested_p2m: Don't walk EPT tables with a regular PT walker") Reported-by: Tamas K Lengyel <tamas@tklengyel.com> Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com> --- CC: Jan Beulich <JBeulich@suse.com> CC: Roger Pau Monné <roger.pau@citrix.com> CC: Wei Liu <wl@xen.org> CC: Tamas K Lengyel <tamas@tklengyel.com> --- xen/arch/x86/mm/p2m.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-)