diff mbox series

[v5,54/65] q35: Introduce smm_ranges property for q35-pci-host

Message ID 20240229063726.610065-55-xiaoyao.li@intel.com (mailing list archive)
State New, archived
Headers show
Series QEMU Guest memfd + QEMU TDX support | expand

Commit Message

Xiaoyao Li Feb. 29, 2024, 6:37 a.m. UTC 
From: Isaku Yamahata <isaku.yamahata@linux.intel.com>

Add a q35 property to check whether or not SMM ranges, e.g. SMRAM, TSEG,
etc... exist for the target platform.  TDX doesn't support SMM and doesn't
play nice with QEMU modifying related guest memory ranges.

Signed-off-by: Isaku Yamahata <isaku.yamahata@linux.intel.com>
Co-developed-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Xiaoyao Li <xiaoyao.li@intel.com>
---
 hw/i386/pc_q35.c          |  2 ++
 hw/pci-host/q35.c         | 42 +++++++++++++++++++++++++++------------
 include/hw/i386/pc.h      |  1 +
 include/hw/pci-host/q35.h |  1 +
 4 files changed, 33 insertions(+), 13 deletions(-)

Comments

Michael Tokarev Oct. 5, 2024, 8:15 a.m. UTC | #1 
29.02.2024 09:37, Xiaoyao Li wrote:
> From: Isaku Yamahata <isaku.yamahata@linux.intel.com>
> 
> Add a q35 property to check whether or not SMM ranges, e.g. SMRAM, TSEG,
> etc... exist for the target platform.  TDX doesn't support SMM and doesn't
> play nice with QEMU modifying related guest memory ranges.

This change introduces a newly reported issue with windows XP:
https://gitlab.com/qemu-project/qemu/-/issues/2608

Can you take a look please?  I've no idea if this is a bug in qemu or not.

Thanks,

/mjt
diff mbox series

Patch

diff --git a/hw/i386/pc_q35.c b/hw/i386/pc_q35.c
index 45a4102e75f5..dc3f68676ea0 100644
--- a/hw/i386/pc_q35.c
+++ b/hw/i386/pc_q35.c
@@ -212,6 +212,8 @@  static void pc_q35_init(MachineState *machine)
                             x86ms->above_4g_mem_size, NULL);
     object_property_set_bool(phb, PCI_HOST_BYPASS_IOMMU,
                              pcms->default_bus_bypass_iommu, NULL);
+    object_property_set_bool(phb, PCI_HOST_PROP_SMM_RANGES,
+                             x86_machine_is_smm_enabled(x86ms), NULL);
     sysbus_realize_and_unref(SYS_BUS_DEVICE(phb), &error_fatal);
 
     /* pci */
diff --git a/hw/pci-host/q35.c b/hw/pci-host/q35.c
index 98d4a7c253a6..0b6cbaed7ed5 100644
--- a/hw/pci-host/q35.c
+++ b/hw/pci-host/q35.c
@@ -179,6 +179,8 @@  static Property q35_host_props[] = {
                      mch.below_4g_mem_size, 0),
     DEFINE_PROP_SIZE(PCI_HOST_ABOVE_4G_MEM_SIZE, Q35PCIHost,
                      mch.above_4g_mem_size, 0),
+    DEFINE_PROP_BOOL(PCI_HOST_PROP_SMM_RANGES, Q35PCIHost,
+                     mch.has_smm_ranges, true),
     DEFINE_PROP_BOOL("x-pci-hole64-fix", Q35PCIHost, pci_hole64_fix, true),
     DEFINE_PROP_END_OF_LIST(),
 };
@@ -214,6 +216,7 @@  static void q35_host_initfn(Object *obj)
     /* mch's object_initialize resets the default value, set it again */
     qdev_prop_set_uint64(DEVICE(s), PCI_HOST_PROP_PCI_HOLE64_SIZE,
                          Q35_PCI_HOST_HOLE64_SIZE_DEFAULT);
+
     object_property_add(obj, PCI_HOST_PROP_PCI_HOLE_START, "uint32",
                         q35_host_get_pci_hole_start,
                         NULL, NULL, NULL);
@@ -476,6 +479,10 @@  static void mch_write_config(PCIDevice *d,
         mch_update_pciexbar(mch);
     }
 
+    if (!mch->has_smm_ranges) {
+        return;
+    }
+
     if (ranges_overlap(address, len, MCH_HOST_BRIDGE_SMRAM,
                        MCH_HOST_BRIDGE_SMRAM_SIZE)) {
         mch_update_smram(mch);
@@ -494,10 +501,13 @@  static void mch_write_config(PCIDevice *d,
 static void mch_update(MCHPCIState *mch)
 {
     mch_update_pciexbar(mch);
+
     mch_update_pam(mch);
-    mch_update_smram(mch);
-    mch_update_ext_tseg_mbytes(mch);
-    mch_update_smbase_smram(mch);
+    if (mch->has_smm_ranges) {
+        mch_update_smram(mch);
+        mch_update_ext_tseg_mbytes(mch);
+        mch_update_smbase_smram(mch);
+    }
 
     /*
      * pci hole goes from end-of-low-ram to io-apic.
@@ -538,19 +548,21 @@  static void mch_reset(DeviceState *qdev)
     pci_set_quad(d->config + MCH_HOST_BRIDGE_PCIEXBAR,
                  MCH_HOST_BRIDGE_PCIEXBAR_DEFAULT);
 
-    d->config[MCH_HOST_BRIDGE_SMRAM] = MCH_HOST_BRIDGE_SMRAM_DEFAULT;
-    d->config[MCH_HOST_BRIDGE_ESMRAMC] = MCH_HOST_BRIDGE_ESMRAMC_DEFAULT;
-    d->wmask[MCH_HOST_BRIDGE_SMRAM] = MCH_HOST_BRIDGE_SMRAM_WMASK;
-    d->wmask[MCH_HOST_BRIDGE_ESMRAMC] = MCH_HOST_BRIDGE_ESMRAMC_WMASK;
+    if (mch->has_smm_ranges) {
+        d->config[MCH_HOST_BRIDGE_SMRAM] = MCH_HOST_BRIDGE_SMRAM_DEFAULT;
+        d->config[MCH_HOST_BRIDGE_ESMRAMC] = MCH_HOST_BRIDGE_ESMRAMC_DEFAULT;
+        d->wmask[MCH_HOST_BRIDGE_SMRAM] = MCH_HOST_BRIDGE_SMRAM_WMASK;
+        d->wmask[MCH_HOST_BRIDGE_ESMRAMC] = MCH_HOST_BRIDGE_ESMRAMC_WMASK;
 
-    if (mch->ext_tseg_mbytes > 0) {
-        pci_set_word(d->config + MCH_HOST_BRIDGE_EXT_TSEG_MBYTES,
-                     MCH_HOST_BRIDGE_EXT_TSEG_MBYTES_QUERY);
+        if (mch->ext_tseg_mbytes > 0) {
+            pci_set_word(d->config + MCH_HOST_BRIDGE_EXT_TSEG_MBYTES,
+                        MCH_HOST_BRIDGE_EXT_TSEG_MBYTES_QUERY);
+        }
+
+        d->config[MCH_HOST_BRIDGE_F_SMBASE] = 0;
+        d->wmask[MCH_HOST_BRIDGE_F_SMBASE] = 0xff;
     }
 
-    d->config[MCH_HOST_BRIDGE_F_SMBASE] = 0;
-    d->wmask[MCH_HOST_BRIDGE_F_SMBASE] = 0xff;
-
     mch_update(mch);
 }
 
@@ -578,6 +590,10 @@  static void mch_realize(PCIDevice *d, Error **errp)
                  PAM_EXPAN_BASE + i * PAM_EXPAN_SIZE, PAM_EXPAN_SIZE);
     }
 
+    if (!mch->has_smm_ranges) {
+        return;
+    }
+
     /* if *disabled* show SMRAM to all CPUs */
     memory_region_init_alias(&mch->smram_region, OBJECT(mch), "smram-region",
                              mch->pci_address_space, MCH_HOST_BRIDGE_SMRAM_C_BASE,
diff --git a/include/hw/i386/pc.h b/include/hw/i386/pc.h
index 5065590281a1..91be8e3b35b5 100644
--- a/include/hw/i386/pc.h
+++ b/include/hw/i386/pc.h
@@ -161,6 +161,7 @@  void pc_acpi_smi_interrupt(void *opaque, int irq, int level);
 #define PCI_HOST_PROP_PCI_HOLE64_SIZE  "pci-hole64-size"
 #define PCI_HOST_BELOW_4G_MEM_SIZE     "below-4g-mem-size"
 #define PCI_HOST_ABOVE_4G_MEM_SIZE     "above-4g-mem-size"
+#define PCI_HOST_PROP_SMM_RANGES       "smm-ranges"
 
 
 void pc_pci_as_mapping_init(MemoryRegion *system_memory,
diff --git a/include/hw/pci-host/q35.h b/include/hw/pci-host/q35.h
index bafcbe675214..22fadfa3ed76 100644
--- a/include/hw/pci-host/q35.h
+++ b/include/hw/pci-host/q35.h
@@ -50,6 +50,7 @@  struct MCHPCIState {
     MemoryRegion tseg_blackhole, tseg_window;
     MemoryRegion smbase_blackhole, smbase_window;
     bool has_smram_at_smbase;
+    bool has_smm_ranges;
     Range pci_hole;
     uint64_t below_4g_mem_size;
     uint64_t above_4g_mem_size;