[Xen-changelog] [xen stable-4.3] nested VMX: fix I/O port exit emulation

[patchbot@xxxxxxx]

commit 5fff433162d9b48c3bb94f2b453f45176a39eb5f
Author:     Jan Beulich <jbeulich@xxxxxxxx>
AuthorDate: Mon Dec 9 14:32:16 2013 +0100
Commit:     Jan Beulich <jbeulich@xxxxxxxx>
CommitDate: Mon Dec 9 14:32:16 2013 +0100

    nested VMX: fix I/O port exit emulation
    
    For multi-byte operations all affected ports' bits in the bitmap need
    to be checked, not just the first port's one.
    
    Reported-by: Matthew Daley <mattd@xxxxxxxxxxx>
    Signed-off-by: Jan Beulich <jbeulich@xxxxxxxx>
    Reviewed-by: Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
    Acked-by: Eddie Dong <eddie.dong@xxxxxxxxx>
    master commit: e1978480c76e36bc22ec12657121ac91d08aca6b
    master date: 2013-12-04 13:23:27 +0100
---
 xen/arch/x86/hvm/vmx/vvmx.c |   22 +++++++++++++++-------
 1 files changed, 15 insertions(+), 7 deletions(-)

diff --git a/xen/arch/x86/hvm/vmx/vvmx.c b/xen/arch/x86/hvm/vmx/vvmx.c
index 9ce02cf..5f07fbb 100644
--- a/xen/arch/x86/hvm/vmx/vvmx.c
+++ b/xen/arch/x86/hvm/vmx/vvmx.c
@@ -2127,8 +2127,6 @@ int nvmx_n2_vmexit_handler(struct cpu_user_regs *regs,
     struct nestedvcpu *nvcpu = &vcpu_nestedhvm(v);
     struct nestedvmx *nvmx = &vcpu_2_nvmx(v);
     u32 ctrl;
-    u16 port;
-    u8 *bitmap;
 
     nvcpu->nv_vmexit_pending = 0;
     nvmx->intr.intr_info = 0;
@@ -2211,12 +2209,22 @@ int nvmx_n2_vmexit_handler(struct cpu_user_regs *regs,
         ctrl = __n2_exec_control(v);
         if ( ctrl & CPU_BASED_ACTIVATE_IO_BITMAP )
         {
-            port = __vmread(EXIT_QUALIFICATION) >> 16;
-            bitmap = nvmx->iobitmap[port >> 15];
-            if ( bitmap[(port & 0x7fff) >> 3] & (1 << (port & 0x7)) )
-                nvcpu->nv_vmexit_pending = 1;
+            unsigned long qual = __vmread(EXIT_QUALIFICATION);
+            u16 port = qual >> 16;
+            u16 size = (qual & 7) + 1;
+
+            do {
+                const u8 *bitmap = nvmx->iobitmap[port >> 15];
+
+                if ( bitmap[(port & 0x7fff) >> 3] & (1 << (port & 7)) )
+                    nvcpu->nv_vmexit_pending = 1;
+                if ( !--size )
+                    break;
+                if ( !++port )
+                    nvcpu->nv_vmexit_pending = 1;
+            } while ( !nvcpu->nv_vmexit_pending );
             if ( !nvcpu->nv_vmexit_pending )
-               gdprintk(XENLOG_WARNING, "L0 PIO %x.\n", port);
+                printk(XENLOG_G_WARNING "L0 PIO %04x\n", port);
         }
         else if ( ctrl & CPU_BASED_UNCOND_IO_EXITING )
             nvcpu->nv_vmexit_pending = 1;
--
generated by git-patchbot for /home/xen/git/xen.git#stable-4.3

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