Changeset 81501 in vbox for trunk

Timestamp:

Oct 24, 2019 1:37:27 AM (5 years ago)

Author:

vboxsync

svn:sync-xref-src-repo-rev:

134229

Message:

VMM/IEMAllCImplStrInstr.cpp.h: Fixed a few incorrect uses of OP_SIZE in aligment mask calculations, code thought it was a byte count when it's a bit count. Also added a optimization for 'rep stos' on unassigned pages as some buggy EFI firmware ended up doing that for hundred of MBs, which takes forever when doing it byte-by-byte of course.

File:

• trunk/src/VBox/VMM/VMMAll/IEMAllCImplStrInstr.cpp.h (modified) (7 diffs)

trunk/src/VBox/VMM/VMMAll/IEMAllCImplStrInstr.cpp.h

@@ -551 +551 @@
                 /* If unaligned, we drop thru and do the page crossing access
                    below. Otherwise, do the next page. */
-                if (!(uVirtAddr & (OP_SIZE - 1)))
+                if (!(uVirtAddr & (OP_SIZE / 8 - 1)))
                 {
                     IEM_CHECK_FF_YIELD_REPSTR_MAYBE_RETURN(pVM, pVCpu, uEFlags);
@@ -683 +683 @@
                 /* If unaligned, we drop thru and do the page crossing access
                    below. Otherwise, do the next page. */
-                if (!(uVirtAddr & (OP_SIZE - 1)))
+                if (!(uVirtAddr & (OP_SIZE / 8 - 1)))
                 {
                     IEM_CHECK_FF_YIELD_REPSTR_MAYBE_RETURN(pVM, pVCpu, uEFlags);
@@ -984 +984 @@
                 /* If unaligned, we drop thru and do the page crossing access
                    below. Otherwise, do the next page. */
-                if (!(uVirtAddr & (OP_SIZE - 1)))
+                if (!(uVirtAddr & (OP_SIZE / 8 - 1)))
                 {
                     IEM_CHECK_FF_YIELD_REPSTR_MAYBE_RETURN(pVM, pVCpu, pVCpu->cpum.GstCtx.eflags.u);
@@ -990 +990 @@
                 }
                 cLeftPage = 0;
+            }
+            /* If we got an invalid physical address in the page table, just skip
+               ahead to the next page or the counter reaches zero.  This crazy
+               optimization is for a buggy EFI firmware that's driving me nuts. */
+            else if (rcStrict == VERR_PGM_PHYS_TLB_UNASSIGNED)
+            {
+                pVCpu->cpum.GstCtx.ADDR_rCX = uCounterReg -= cLeftPage;
+                pVCpu->cpum.GstCtx.ADDR_rDI = uAddrReg    += cLeftPage * cbIncr;
+                if (uCounterReg == 0)
+                    break;
+                if (!(uVirtAddr & (OP_SIZE / 8 - 1)))
+                {
+                    IEM_CHECK_FF_YIELD_REPSTR_MAYBE_RETURN(pVM, pVCpu, pVCpu->cpum.GstCtx.eflags.u);
+                    continue;
+                }
             }
         }
@@ -1101 +1116 @@
                 /* If unaligned, we drop thru and do the page crossing access
                    below. Otherwise, do the next page. */
-                if (!(uVirtAddr & (OP_SIZE - 1)))
+                if (!(uVirtAddr & (OP_SIZE / 8 - 1)))
                 {
                     IEM_CHECK_FF_YIELD_REPSTR_MAYBE_RETURN(pVM, pVCpu, pVCpu->cpum.GstCtx.eflags.u);
@@ -1384 +1399 @@
                 if (uCounterReg == 0)
                     break;
-                if (!(uVirtAddr & (OP_SIZE - 1)))
+                if (!(uVirtAddr & (OP_SIZE / 8 - 1)))
                 {
                     IEM_CHECK_FF_YIELD_REPSTR_MAYBE_RETURN(pVM, pVCpu, pVCpu->cpum.GstCtx.eflags.u);
@@ -1665 +1680 @@
                 /* If unaligned, we drop thru and do the page crossing access
                    below. Otherwise, do the next page. */
-                if (!(uVirtAddr & (OP_SIZE - 1)))
+                if (!(uVirtAddr & (OP_SIZE / 8 - 1)))
                 {
                     IEM_CHECK_FF_YIELD_REPSTR_MAYBE_RETURN(pVM, pVCpu, pVCpu->cpum.GstCtx.eflags.u);