Check return value of msix_init() and return early on
failure instead of continuing with invalid state.
- Use ret < 0 to handle negative return value.
- Use errp parameter to handle failure instead of NULL.
- No functional changes.

Resolves: https://gitlab.com/qemu-project/qemu/-/issues/413
Signed-off-by: Trieu Huynh <vikingtc4@gmail.com>
---
 hw/net/igbvf.c         |  2 +-
 hw/net/rocker/rocker.c |  2 +-
 hw/pci/msix.c          |  2 +-
 hw/scsi/megasas.c      | 16 +++++++++++-----
 hw/usb/hcd-xhci-pci.c  | 16 +++++++++++-----
 5 files changed, 25 insertions(+), 13 deletions(-)

diff --git a/hw/net/igbvf.c b/hw/net/igbvf.c
index 48d56e43ac..9a165c7063 100644
--- a/hw/net/igbvf.c
+++ b/hw/net/igbvf.c
@@ -260,7 +260,7 @@ static void igbvf_pci_realize(PCIDevice *dev, Error **errp)
 
     ret = msix_init(dev, IGBVF_MSIX_VEC_NUM, &s->msix, IGBVF_MSIX_BAR_IDX, 0,
         &s->msix, IGBVF_MSIX_BAR_IDX, 0x2000, 0x70, errp);
-    if (ret) {
+    if (ret < 0) {
         return;
     }
 
diff --git a/hw/net/rocker/rocker.c b/hw/net/rocker/rocker.c
index 4a7056bd45..910dce901b 100644
--- a/hw/net/rocker/rocker.c
+++ b/hw/net/rocker/rocker.c
@@ -1228,7 +1228,7 @@ static int rocker_msix_init(Rocker *r, Error **errp)
                     &r->msix_bar,
                     ROCKER_PCI_MSIX_BAR_IDX, ROCKER_PCI_MSIX_PBA_OFFSET,
                     0, errp);
-    if (err) {
+    if (err < 0) {
         return err;
     }
 
diff --git a/hw/pci/msix.c b/hw/pci/msix.c
index b35476d057..1b23eaf100 100644
--- a/hw/pci/msix.c
+++ b/hw/pci/msix.c
@@ -432,7 +432,7 @@ int msix_init_exclusive_bar(PCIDevice *dev, uint32_t nentries,
                     0, &dev->msix_exclusive_bar,
                     bar_nr, bar_pba_offset,
                     0, errp);
-    if (ret) {
+    if (ret < 0) {
         return ret;
     }
 
diff --git a/hw/scsi/megasas.c b/hw/scsi/megasas.c
index f62e420a91..a29742d449 100644
--- a/hw/scsi/megasas.c
+++ b/hw/scsi/megasas.c
@@ -2380,11 +2380,17 @@ static void megasas_scsi_realize(PCIDevice *dev, Error **errp)
     memory_region_init_io(&s->queue_io, OBJECT(s), &megasas_queue_ops, s,
                           "megasas-queue", 0x40000);
 
-    if (megasas_use_msix(s) &&
-        msix_init(dev, 15, &s->mmio_io, b->mmio_bar, 0x2000,
-                  &s->mmio_io, b->mmio_bar, 0x3800, 0x68, NULL)) {
-        /* TODO: check msix_init's error, and should fail on msix=on */
-        s->msix = ON_OFF_AUTO_OFF;
+    if (megasas_use_msix(s)) {
+        ret = msix_init(dev, 15, &s->mmio_io, b->mmio_bar, 0x2000,
+                        &s->mmio_io, b->mmio_bar, 0x3800, 0x68,
+                        s->msix == ON_OFF_AUTO_ON ? errp : NULL);
+
+        if (ret < 0) {
+            if (s->msix == ON_OFF_AUTO_ON) {
+                return;
+            }
+            s->msix = ON_OFF_AUTO_OFF;
+        }
     }
 
     if (pci_is_express(dev)) {
diff --git a/hw/usb/hcd-xhci-pci.c b/hw/usb/hcd-xhci-pci.c
index aa570506fc..c5446a4a5e 100644
--- a/hw/usb/hcd-xhci-pci.c
+++ b/hw/usb/hcd-xhci-pci.c
@@ -173,11 +173,17 @@ static void usb_xhci_pci_realize(struct PCIDevice *dev, Error **errp)
     }
 
     if (s->msix != ON_OFF_AUTO_OFF) {
-        /* TODO check for errors, and should fail when msix=on */
-        msix_init(dev, s->xhci.numintrs,
-                  &s->xhci.mem, 0, OFF_MSIX_TABLE,
-                  &s->xhci.mem, 0, OFF_MSIX_PBA,
-                  0x90, NULL);
+        ret = msix_init(dev, s->xhci.numintrs,
+                        &s->xhci.mem, 0, OFF_MSIX_TABLE,
+                        &s->xhci.mem, 0, OFF_MSIX_PBA,
+                        0x90, s->msix == ON_OFF_AUTO_ON ? errp : NULL);
+
+        if (ret < 0) {
+            if (s->msix == ON_OFF_AUTO_ON) {
+                return;
+            }
+            s->msix = ON_OFF_AUTO_OFF;
+        }
     }
     s->xhci.as = pci_get_address_space(dev);
 }
-- 
2.43.0

On Wed, 18 Mar 2026 at 14:16, Trieu Huynh <vikingtc4@gmail.com> wrote:
>
> Check return value of msix_init() and return early on
> failure instead of continuing with invalid state.
> - Use ret < 0 to handle negative return value.
> - Use errp parameter to handle failure instead of NULL.
> - No functional changes.
>
> Resolves: https://gitlab.com/qemu-project/qemu/-/issues/413
> Signed-off-by: Trieu Huynh <vikingtc4@gmail.com>
> ---

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>

thanks
-- PMM