x86: always supply .cpuid() handler to x86_emulate()

With us incremementally adding proper CPUID checks to x86_emulate()
(see commit de05bd965a ["x86emul: correct {,F}CMOV and F{,U}COMI{,P}
emulation"]) it is no longer appropriate to invoke the function with
that hook being NULL, as long as respective instructions may get used
in that case.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Paul Durrant <paul.durrant@citrix.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Release-acked-by: Wei Liu <wei.liu2@citrix.com>

diff --git a/xen/arch/x86/hvm/emulate.c b/xen/arch/x86/hvm/emulate.c
index 5b408f8eb97200b3e3965df369457a390878533b..e9b8f8c40d75e18f1f3ca9a33be1dcc5aab0c6cd 100644 (file)
--- a/xen/arch/x86/hvm/emulate.c
+++ b/xen/arch/x86/hvm/emulate.c
@@ -1542,7 +1542,7 @@ static int hvmemul_wbinvd(
     return X86EMUL_OKAY;
 }
 
-static int hvmemul_cpuid(
+int hvmemul_cpuid(
     unsigned int *eax,
     unsigned int *ebx,
     unsigned int *ecx,
@@ -1892,11 +1892,13 @@ int hvm_emulate_one_mmio(unsigned long mfn, unsigned long gla)
         .read       = x86emul_unhandleable_rw,
         .insn_fetch = hvmemul_insn_fetch,
         .write      = mmcfg_intercept_write,
+        .cpuid      = hvmemul_cpuid,
     };
     static const struct x86_emulate_ops hvm_ro_emulate_ops_mmio = {
         .read       = x86emul_unhandleable_rw,
         .insn_fetch = hvmemul_insn_fetch,
-        .write      = mmio_ro_emulated_write
+        .write      = mmio_ro_emulated_write,
+        .cpuid      = hvmemul_cpuid,
     };
     struct mmio_ro_emulate_ctxt mmio_ro_ctxt = { .cr2 = gla };
     struct hvm_emulate_ctxt ctxt;

diff --git a/xen/arch/x86/mm.c b/xen/arch/x86/mm.c
index eddf098fe6d6a5a312a50a77fa8690cf5d704559..03dcd710d66abaee7a76b8fb461b0e11a62f6fb4 100644 (file)
--- a/xen/arch/x86/mm.c
+++ b/xen/arch/x86/mm.c
@@ -5327,6 +5327,7 @@ static const struct x86_emulate_ops ptwr_emulate_ops = {
     .insn_fetch = ptwr_emulated_read,
     .write      = ptwr_emulated_write,
     .cmpxchg    = ptwr_emulated_cmpxchg,
+    .cpuid      = pv_emul_cpuid,
 };
 
 /* Write page fault handler: check if guest is trying to modify a PTE. */
@@ -5414,6 +5415,7 @@ static const struct x86_emulate_ops mmio_ro_emulate_ops = {
     .read       = x86emul_unhandleable_rw,
     .insn_fetch = ptwr_emulated_read,
     .write      = mmio_ro_emulated_write,
+    .cpuid      = pv_emul_cpuid,
 };
 
 int mmcfg_intercept_write(
@@ -5451,6 +5453,7 @@ static const struct x86_emulate_ops mmcfg_intercept_ops = {
     .read       = x86emul_unhandleable_rw,
     .insn_fetch = ptwr_emulated_read,
     .write      = mmcfg_intercept_write,
+    .cpuid      = pv_emul_cpuid,
 };
 
 /* Check if guest is trying to modify a r/o MMIO page. */

diff --git a/xen/arch/x86/mm/shadow/common.c b/xen/arch/x86/mm/shadow/common.c
index 21607bf34aad04f08546b6581d182d9d981d4f0c..ced23138c8947e7557d9e5c7c0ef79c34cefa7c7 100644 (file)
--- a/xen/arch/x86/mm/shadow/common.c
+++ b/xen/arch/x86/mm/shadow/common.c
@@ -306,6 +306,7 @@ static const struct x86_emulate_ops hvm_shadow_emulator_ops = {
     .insn_fetch = hvm_emulate_insn_fetch,
     .write      = hvm_emulate_write,
     .cmpxchg    = hvm_emulate_cmpxchg,
+    .cpuid      = hvmemul_cpuid,
 };
 
 static int
@@ -374,6 +375,7 @@ static const struct x86_emulate_ops pv_shadow_emulator_ops = {
     .insn_fetch = pv_emulate_read,
     .write      = pv_emulate_write,
     .cmpxchg    = pv_emulate_cmpxchg,
+    .cpuid      = pv_emul_cpuid,
 };
 
 const struct x86_emulate_ops *shadow_init_emulation(

diff --git a/xen/arch/x86/traps.c b/xen/arch/x86/traps.c
index 822556a8e08af0eeac85983328777603609cda91..14abb62a4d0852777b3532fe9fca7cd1644cfac9 100644 (file)
--- a/xen/arch/x86/traps.c
+++ b/xen/arch/x86/traps.c
@@ -2755,6 +2755,24 @@ static int priv_op_write_msr(unsigned int reg, uint64_t val,
     return X86EMUL_UNHANDLEABLE;
 }
 
+int pv_emul_cpuid(unsigned int *eax, unsigned int *ebx, unsigned int *ecx,
+                  unsigned int *edx, struct x86_emulate_ctxt *ctxt)
+{
+    struct cpu_user_regs regs = *ctxt->regs;
+
+    regs._eax = *eax;
+    regs._ecx = *ecx;
+
+    pv_cpuid(&regs);
+
+    *eax = regs._eax;
+    *ebx = regs._ebx;
+    *ecx = regs._ecx;
+    *edx = regs._edx;
+
+    return X86EMUL_OKAY;
+}
+
 /* Instruction fetch with error handling. */
 #define insn_fetch(type, base, eip, limit)                                  \
 ({  unsigned long _rc, _ptr = (base) + (eip);                               \

diff --git a/xen/include/asm-x86/hvm/emulate.h b/xen/include/asm-x86/hvm/emulate.h
index 1055563b72233029fd1cdac90392e6c82c5c0640..f6106732050ddfc3d9e4d2bba7fd9ca4031c81a9 100644 (file)
--- a/xen/include/asm-x86/hvm/emulate.h
+++ b/xen/include/asm-x86/hvm/emulate.h
@@ -60,6 +60,12 @@ void hvm_emulate_init(
     unsigned int insn_bytes);
 void hvm_emulate_writeback(
     struct hvm_emulate_ctxt *hvmemul_ctxt);
+int hvmemul_cpuid(
+    unsigned int *eax,
+    unsigned int *ebx,
+    unsigned int *ecx,
+    unsigned int *edx,
+    struct x86_emulate_ctxt *ctxt);
 struct segment_register *hvmemul_get_seg_reg(
     enum x86_segment seg,
     struct hvm_emulate_ctxt *hvmemul_ctxt);

diff --git a/xen/include/asm-x86/mm.h b/xen/include/asm-x86/mm.h
index b781495abebb595965f3e8a2b57429ef8cedae4a..1b4d1c336a6857323732924746b579ac573dad65 100644 (file)
--- a/xen/include/asm-x86/mm.h
+++ b/xen/include/asm-x86/mm.h
@@ -504,6 +504,8 @@ extern int mmcfg_intercept_write(enum x86_segment seg,
                                  void *p_data,
                                  unsigned int bytes,
                                  struct x86_emulate_ctxt *ctxt);
+int pv_emul_cpuid(unsigned int *eax, unsigned int *ebx, unsigned int *ecx,
+                  unsigned int *edx, struct x86_emulate_ctxt *ctxt);
 
 int  ptwr_do_page_fault(struct vcpu *, unsigned long,
                         struct cpu_user_regs *);