Re: [Qemu-devel] [PATCH v3 2/7] s390x/pci: rework PCI STORE

[Pierre Morel]

On 23/11/2017 10:01, Thomas Huth wrote:

On 22.11.2017 23:05, Pierre Morel wrote:

Enhance the fault detection, correction of the fault reporting.

Signed-off-by: Pierre Morel <pmo...@linux.vnet.ibm.com>
Reviewed-by: Yi Min Zhao <zyi...@linux.vnet.ibm.com>
---
  hw/s390x/s390-pci-inst.c | 39 ++++++++++++++++++++++-----------------
  1 file changed, 22 insertions(+), 17 deletions(-)

diff --git a/hw/s390x/s390-pci-inst.c b/hw/s390x/s390-pci-inst.c
index 3e1f1a0..930c197 100644
--- a/hw/s390x/s390-pci-inst.c
+++ b/hw/s390x/s390-pci-inst.c
@@ -470,6 +470,12 @@ int pcistg_service_call(S390CPU *cpu, uint8_t r1, uint8_t 
r2)
      pcias = (env->regs[r2] >> 16) & 0xf;
      len = env->regs[r2] & 0xf;
      offset = env->regs[r2 + 1];
+    data = env->regs[r1];
+
+    if (!(fh & FH_MASK_ENABLE)) {
+        setcc(cpu, ZPCI_PCI_LS_INVAL_HANDLE);
+        return 0;
+    }

pbdev = s390_pci_find_dev_by_fh(s390_get_phb(), fh);

      if (!pbdev) {
@@ -479,12 +485,7 @@ int pcistg_service_call(S390CPU *cpu, uint8_t r1, uint8_t 
r2)
      }

switch (pbdev->state) {

-    case ZPCI_FS_RESERVED:
-    case ZPCI_FS_STANDBY:
-    case ZPCI_FS_DISABLED:
      case ZPCI_FS_PERMANENT_ERROR:
-        setcc(cpu, ZPCI_PCI_LS_INVAL_HANDLE);
-        return 0;
      case ZPCI_FS_ERROR:
          setcc(cpu, ZPCI_PCI_LS_ERR);
          s390_set_status_code(env, r2, ZPCI_PCI_ST_BLOCKED);

-EMISSINGPUBLICDOCUMENTATION

Hi Thomas,

I do not understand what you mean here

@@ -493,9 +494,13 @@ int pcistg_service_call(S390CPU *cpu, uint8_t r1, uint8_t 
r2)
          break;
      }

- data = env->regs[r1];

-    if (pcias < 6) {
-        if ((8 - (offset & 0x7)) < len) {
+    switch (pcias) {
+        /* A ZPCI PCI card may use any BAR from BAR 0 to BAR 5 */
+    case 0 ... 5:
+        /* Check length:
+         * A length of 0 is invalid and length should not cross a double word
+         */
+        if (!len || (len > (8 - (offset & 0x7)))) {
              program_interrupt(env, PGM_OPERAND, 4);
              return 0;
          }
@@ -513,21 +518,21 @@ int pcistg_service_call(S390CPU *cpu, uint8_t r1, uint8_t 
r2)
              program_interrupt(env, PGM_OPERAND, 4);
              return 0;
          }
-    } else if (pcias == 15) {
-        if ((4 - (offset & 0x3)) < len) {
-            program_interrupt(env, PGM_OPERAND, 4);
-            return 0;
-        }
-
-        if (zpci_endian_swap(&data, len)) {
+        break;
+    case 15:
+        /* ZPCI uses the pseudo BAR number 15 as configuration space */
+        /* possible access lengths are 1,2,4 and must not cross a word */
+        if (!len || (len > (4 - (offset & 0x3))) || len == 3) {
              program_interrupt(env, PGM_OPERAND, 4);
              return 0;
          }
-
+        /* len = 1,2,4 so we do not need to test */
+        zpci_endian_swap(&data, len);
          pci_host_config_write_common(pbdev->pdev, offset,
                                       pci_config_size(pbdev->pdev),
                                       data, len);
-    } else {
+        break;
+    default:
          DPRINTF("pcistg invalid space\n");
          setcc(cpu, ZPCI_PCI_LS_ERR);
          s390_set_status_code(env, r2, ZPCI_PCI_ST_INVAL_AS);

At least the last two hunks looks fine to me. If you want to have a
Reviewed-by for this, you could maybe put these two hunks into a
separate patch instead?

I do not understand what yo umean with the first one.
Can you explain?

Thanks

Pierre

  Thomas

--
Pierre Morel
Linux/KVM/QEMU in Böblingen - Germany