git: 5cb5b368829d - stable/12 - e1000: fix VLAN 0

The branch stable/12 has been updated by kp:

URL: https://cgit.FreeBSD.org/src/commit/?id=5cb5b368829dd075bec55ada6c1374538ec7c6d0

commit 5cb5b368829dd075bec55ada6c1374538ec7c6d0
Author:     Kristof Provost <kp@FreeBSD.org>
AuthorDate: 2023-05-10 16:26:29 +0000
Commit:     Kristof Provost <kp@FreeBSD.org>
CommitDate: 2023-05-15 04:49:51 +0000

    e1000: fix VLAN 0
    
    VLAN 0 essentially means "Treat as untagged, but with priority bits",
    and is used by some ISPs.
    
    On igb/em interfaces we did not receive packets with VLAN tag 0 unless
    vlanhwfilter was disabled.
    
    This can be fixed by explicitly listing VLAN 0 in the hardware VLAN
    filter (VFTA). Do this from em_setup_vlan_hw_support(), where we already
    (re-)write the VFTA.
    
    Reviewed by:    kbowling
    Sponsored by:   Rubicon Communications, LLC ("Netgate")
    Differential Revision:  https://reviews.freebsd.org/D40046
    
    (cherry picked from commit 0229fab2fe0eed843ebec98fd31b7d49bb2e8438)
---
 sys/dev/e1000/if_em.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/sys/dev/e1000/if_em.c b/sys/dev/e1000/if_em.c
index 8a489c48bf85..3e41e1e0bff1 100644
--- a/sys/dev/e1000/if_em.c
+++ b/sys/dev/e1000/if_em.c
@@ -3671,8 +3671,10 @@ em_setup_vlan_hw_support(if_ctx_t ctx)
 	/*
 	 * A soft reset zero's out the VFTA, so
 	 * we need to repopulate it now.
+	 * We also insert VLAN 0 in the filter list, so we pass VLAN 0 tagged
+	 * traffic through. This will write the entire table.
 	 */
-	em_if_vlan_filter_write(sc);
+	em_if_vlan_register(ctx, 0);
 
 	/* Enable the Filter Table */
 	em_if_vlan_filter_enable(sc);