6.10-stable review patch. If anyone has any objections, please let me know.
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From: Paolo Abeni pabeni@redhat.com
[ Upstream commit 8aba27c4a5020abdf60149239198297f88338a8d ]
Sabrina reports that the igb driver does not cope well with large MAX_SKB_FRAG values: setting MAX_SKB_FRAG to 45 causes payload corruption on TX.
An easy reproducer is to run ssh to connect to the machine. With MAX_SKB_FRAGS=17 it works, with MAX_SKB_FRAGS=45 it fails. This has been reported originally in https://bugzilla.redhat.com/show_bug.cgi?id=2265320
The root cause of the issue is that the driver does not take into account properly the (possibly large) shared info size when selecting the ring layout, and will try to fit two packets inside the same 4K page even when the 1st fraglist will trump over the 2nd head.
Address the issue by checking if 2K buffers are insufficient.
Fixes: 3948b05950fd ("net: introduce a config option to tweak MAX_SKB_FRAGS") Reported-by: Jan Tluka jtluka@redhat.com Reported-by: Jirka Hladky jhladky@redhat.com Reported-by: Sabrina Dubroca sd@queasysnail.net Tested-by: Sabrina Dubroca sd@queasysnail.net Tested-by: Corinna Vinschen vinschen@redhat.com Signed-off-by: Paolo Abeni pabeni@redhat.com Signed-off-by: Corinna Vinschen vinschen@redhat.com Link: https://patch.msgid.link/20240816152034.1453285-1-vinschen@redhat.com Signed-off-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/ethernet/intel/igb/igb_main.c | 1 + 1 file changed, 1 insertion(+)
diff --git a/drivers/net/ethernet/intel/igb/igb_main.c b/drivers/net/ethernet/intel/igb/igb_main.c index fce2930ae6af7..b6aa449aa56af 100644 --- a/drivers/net/ethernet/intel/igb/igb_main.c +++ b/drivers/net/ethernet/intel/igb/igb_main.c @@ -4809,6 +4809,7 @@ static void igb_set_rx_buffer_len(struct igb_adapter *adapter,
#if (PAGE_SIZE < 8192) if (adapter->max_frame_size > IGB_MAX_FRAME_BUILD_SKB || + IGB_2K_TOO_SMALL_WITH_PADDING || rd32(E1000_RCTL) & E1000_RCTL_SBP) set_ring_uses_large_buffer(rx_ring); #endif