Re: [PATCH 07/17] pnv_phb4.c: check if root port exists in rc_config functions

[Cédric Le Goater]

On 12/28/21 20:37, Daniel Henrique Barboza wrote:

pnv_phb4_rc_config_read() and pnv_phb4_rc_config_write() are asserting
the existence of the root port. The root port is now optional, and there
will be cases where a pnv-phb4 device won't have a root port attached.

May be we should enforce a stronger link between the two objects to avoid
creating an empty PHB device.

Instead of asserting, check if the root port exists before read/writing

into it> Signed-off-by: Daniel Henrique Barboza <danielhb...@gmail.com>

---
  hw/pci-host/pnv_phb4.c | 8 ++++++--
  1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/hw/pci-host/pnv_phb4.c b/hw/pci-host/pnv_phb4.c
index daa468b812..6bd907f91a 100644
--- a/hw/pci-host/pnv_phb4.c
+++ b/hw/pci-host/pnv_phb4.c
@@ -152,7 +152,9 @@ static void pnv_phb4_rc_config_write(PnvPHB4 *phb, unsigned 
off,
      }

pdev = pci_find_device(pci->bus, 0, 0);

-    assert(pdev);
+    if (!pdev) {

We should log an error at least.

+        return;
+    }

pci_host_config_write_common(pdev, off, PHB_RC_CONFIG_SIZE,

                                   bswap32(val), 4);
@@ -171,7 +173,9 @@ static uint64_t pnv_phb4_rc_config_read(PnvPHB4 *phb, 
unsigned off,
      }

pdev = pci_find_device(pci->bus, 0, 0);

-    assert(pdev);
+    if (!pdev) {
+        return 0x0;

        return ~0ull;

+    }

val = pci_host_config_read_common(pdev, off, PHB_RC_CONFIG_SIZE, 4);

      return bswap32(val);