From: Keir Fraser <keir.fraser@citrix.com>
Date: Thu, 31 Jul 2008 11:11:00 +0000 (+0100)
Subject: x86: Handle p2m_ram_ro with HAP
X-Git-Tag: archive/raspbian/4.8.0-1+rpi1~1^2~14165^2~67
X-Git-Url: https://dgit.raspbian.org/?a=commitdiff_plain;h=e00bff2cd33a2fbbef8a250865bc39e9cbe10a32;p=xen.git

x86: Handle p2m_ram_ro with HAP

I realized that I had failed to cover the hardware assisted paging
case in my earlier p2m_ram_ro patches. This should fix it.

Signed-off-by: Trolle Selander <trolle.selander@eu.citrix.com>
---

diff --git a/xen/arch/x86/hvm/svm/svm.c b/xen/arch/x86/hvm/svm/svm.c
index ea72939413..9b0b86d426 100644
--- a/xen/arch/x86/hvm/svm/svm.c
+++ b/xen/arch/x86/hvm/svm/svm.c
@@ -874,9 +874,12 @@ static void svm_do_nested_pgfault(paddr_t gpa, struct cpu_user_regs *regs)
     mfn_t mfn;
     unsigned long gfn = gpa >> PAGE_SHIFT;
 
-    /* If this GFN is emulated MMIO, pass the fault to the mmio handler */
+    /*
+     * If this GFN is emulated MMIO or marked as read-only, pass the fault
+     * to the mmio handler.
+     */
     mfn = gfn_to_mfn_current(gfn, &p2mt);
-    if ( p2mt == p2m_mmio_dm )
+    if ( (p2mt == p2m_mmio_dm) || (p2mt == p2m_ram_ro) )
     {
         if ( !handle_mmio() )
             hvm_inject_exception(TRAP_gp_fault, 0, 0);
diff --git a/xen/arch/x86/hvm/vmx/vmx.c b/xen/arch/x86/hvm/vmx/vmx.c
index fbefbd7f75..161a36dec4 100644
--- a/xen/arch/x86/hvm/vmx/vmx.c
+++ b/xen/arch/x86/hvm/vmx/vmx.c
@@ -1971,7 +1971,7 @@ static void ept_handle_violation(unsigned long qualification, paddr_t gpa)
     }
 
     mfn = gfn_to_mfn(d, gfn, &t);
-    if ( p2m_is_ram(t) && paging_mode_log_dirty(d) )
+    if ( (t != p2m_ram_ro) && p2m_is_ram(t) && paging_mode_log_dirty(d) )
     {
         paging_mark_dirty(d, mfn_x(mfn));
         p2m_change_type(d, gfn, p2m_ram_logdirty, p2m_ram_rw);
diff --git a/xen/include/asm-x86/p2m.h b/xen/include/asm-x86/p2m.h
index 4e478502c3..4909c06591 100644
--- a/xen/include/asm-x86/p2m.h
+++ b/xen/include/asm-x86/p2m.h
@@ -61,7 +61,7 @@ typedef enum {
     p2m_invalid = 0,            /* Nothing mapped here */
     p2m_ram_rw = 1,             /* Normal read/write guest RAM */
     p2m_ram_logdirty = 2,       /* Temporarily read-only for log-dirty */
-    p2m_ram_ro = 3,             /* Read-only; writes go to the device model */
+    p2m_ram_ro = 3,             /* Read-only; writes are silently dropped */
     p2m_mmio_dm = 4,            /* Reads and write go to the device model */
     p2m_mmio_direct = 5,        /* Read/write mapping of genuine MMIO area */
 } p2m_type_t;