Re: [PATCH v3] vfio/pci: Propagate errors in vfio_pci_load_rom() using Error API

[Cédric Le Goater]

Hello Mario,

On 6/22/26 14:09, Mario Casquero wrote:
Updates vfio_pci_load_rom() to use Error API for error propagation
instead of error_report(), improving error handling consistency.
Signed-off-by: Mario Casquero <mcasq...@redhat.com>
---
  hw/vfio/pci.c | 24 ++++++++++++++++--------
  1 file changed, 16 insertions(+), 8 deletions(-)


It is helpful for reviewers/maintainers to have a brief changelog here.
 
diff --git a/hw/vfio/pci.c b/hw/vfio/pci.c
index 9df04fa2d7..e7afcc0a1a 100644
--- a/hw/vfio/pci.c
+++ b/hw/vfio/pci.c
@@ -1027,7 +1027,7 @@ static void vfio_update_msi(VFIOPCIDevice *vdev)
      }
  }
  
-static bool vfio_pci_load_rom(VFIOPCIDevice *vdev)
+static bool vfio_pci_load_rom(VFIOPCIDevice *vdev, Error **errp)
  {
      VFIODevice *vbasedev = &vdev->vbasedev;
      struct vfio_region_info *reg_info = NULL;
@@ -1040,7 +1040,7 @@ static bool vfio_pci_load_rom(VFIOPCIDevice *vdev)
                                        &reg_info);
  
      if (ret != 0) {
-        error_report("vfio: Error getting ROM info: %s", strerror(-ret));
+        error_setg_errno(errp, -ret, "vfio: Error getting ROM info");
          return false;
      }
  
@@ -1052,7 +1052,8 @@ static bool vfio_pci_load_rom(VFIOPCIDevice *vdev)
      vdev->rom_offset = reg_info->offset;
  
      if (!vdev->rom_size) {
-        error_report("vfio-pci: Cannot read device rom at %s", vbasedev->name);
+        error_setg(errp, "vfio-pci: Cannot read device rom at %s",
+                   vbasedev->name);
          error_printf("Device option ROM contents are probably invalid "
                      "(check dmesg).\nSkip option ROM probe with rombar=0, "
                      "or load from file with romfile=\n");

error_setg() and error_printf() outputs will be in reverse order now.
Please use error_append_hint() for the second message.

Also, while at it, an since this is an error case, we should reset
rom_size and rom_offset :

           vdev->rom_size = 0;
           vdev->rom_offset = 0;
 
like done below.

Thanks,

C.

@@ -1076,10 +1077,12 @@ static bool vfio_pci_load_rom(VFIOPCIDevice *vdev)
              if (bytes == -EINTR || bytes == -EAGAIN) {
                  continue;
              }
-            error_report("vfio: Error reading device ROM: %s",
-                         strreaderror(bytes));
-
-            break;
+            error_setg_errno(errp, -bytes, "vfio: Error reading device ROM");
+            g_free(vdev->rom);
+            vdev->rom = NULL;
+            vdev->rom_size = 0;
+            vdev->rom_offset = 0;
+            return false;
          }
      }
  
@@ -1147,7 +1150,12 @@ static uint64_t vfio_rom_read(void *opaque, hwaddr addr, unsigned size)
  
      /* Load the ROM lazily when the guest tries to read it */
      if (unlikely(!vdev->rom && !vdev->rom_read_failed)) {
-        vdev->rom_read_failed = !vfio_pci_load_rom(vdev);
+        Error *local_err = NULL;
+
+        vdev->rom_read_failed = !vfio_pci_load_rom(vdev, &local_err);
+        if (vdev->rom_read_failed) {
+            error_report_err(local_err);
+        }
      }
  
      memcpy(&val, vdev->rom + addr,