Merge branch 'nfp-protect-from-theoretical-size-overflows-and-SR-IOV-errors'

Jakub Kicinski says:

====================
nfp: protect from theoretical size overflows and SR-IOV errors

This small set changes the handling of pci_sriov_set_totalvfs() errors.
nfp is the only driver which fails probe on pci_sriov_set_totalvfs()
errors.  It turns out some BIOS configurations may break SR-IOV and
users who don't use that feature should not suffer.

Remaining patches makes sure we use overflow-safe function for ring
allocation, even though ring sizes are limited.  It won't hurt and
we can also enable fallback to vmalloc() if memory is tight while
at it.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 12 insertions, 8 deletions

diff --git a/drivers/net/ethernet/netronome/nfp/nfp_main.c b/drivers/net/ethernet/netronome/nfp/nfp_main.c
index 152283d7e59c..4a540c5e27fe 100644
--- a/drivers/net/ethernet/netronome/nfp/nfp_main.c
+++ b/drivers/net/ethernet/netronome/nfp/nfp_main.c
@@ -236,16 +236,20 @@ static int nfp_pcie_sriov_read_nfd_limit(struct nfp_pf *pf)
 	int err;
 
 	pf->limit_vfs = nfp_rtsym_read_le(pf->rtbl, "nfd_vf_cfg_max_vfs", &err);
-	if (!err)
-		return pci_sriov_set_totalvfs(pf->pdev, pf->limit_vfs);
+	if (err) {
+		/* For backwards compatibility if symbol not found allow all */
+		pf->limit_vfs = ~0;
+		if (err == -ENOENT)
+			return 0;
 
-	pf->limit_vfs = ~0;
-	/* Allow any setting for backwards compatibility if symbol not found */
-	if (err == -ENOENT)
-		return 0;
+		nfp_warn(pf->cpp, "Warning: VF limit read failed: %d\n", err);
+		return err;
+	}
 
-	nfp_warn(pf->cpp, "Warning: VF limit read failed: %d\n", err);
-	return err;
+	err = pci_sriov_set_totalvfs(pf->pdev, pf->limit_vfs);
+	if (err)
+		nfp_warn(pf->cpp, "Failed to set VF count in sysfs: %d\n", err);
+	return 0;
 }
 
 static int nfp_pcie_sriov_enable(struct pci_dev *pdev, int num_vfs)