From f232af4295653afa4ade3230462b3be15ad16419 Mon Sep 17 00:00:00 2001 From: Íñigo Huguet Date: Wed, 14 Sep 2022 12:36:48 +0200 Subject: sfc: fix TX channel offset when using legacy interrupts MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit In legacy interrupt mode the tx_channel_offset was hardcoded to 1, but that's not correct if efx_sepparate_tx_channels is false. In that case, the offset is 0 because the tx queues are in the single existing channel at index 0, together with the rx queue. Without this fix, as soon as you try to send any traffic, it tries to get the tx queues from an uninitialized channel getting these errors: WARNING: CPU: 1 PID: 0 at drivers/net/ethernet/sfc/tx.c:540 efx_hard_start_xmit+0x12e/0x170 [sfc] [...] RIP: 0010:efx_hard_start_xmit+0x12e/0x170 [sfc] [...] Call Trace: dev_hard_start_xmit+0xd7/0x230 sch_direct_xmit+0x9f/0x360 __dev_queue_xmit+0x890/0xa40 [...] BUG: unable to handle kernel NULL pointer dereference at 0000000000000020 [...] RIP: 0010:efx_hard_start_xmit+0x153/0x170 [sfc] [...] Call Trace: dev_hard_start_xmit+0xd7/0x230 sch_direct_xmit+0x9f/0x360 __dev_queue_xmit+0x890/0xa40 [...] Fixes: c308dfd1b43e ("sfc: fix wrong tx channel offset with efx_separate_tx_channels") Reported-by: Tianhao Zhao Signed-off-by: Íñigo Huguet Acked-by: Edward Cree Link: https://lore.kernel.org/r/20220914103648.16902-1-ihuguet@redhat.com Signed-off-by: Jakub Kicinski --- drivers/net/ethernet/sfc/efx_channels.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers/net') diff --git a/drivers/net/ethernet/sfc/efx_channels.c b/drivers/net/ethernet/sfc/efx_channels.c index 032b8c0bd788..5b4d661ab986 100644 --- a/drivers/net/ethernet/sfc/efx_channels.c +++ b/drivers/net/ethernet/sfc/efx_channels.c @@ -319,7 +319,7 @@ int efx_probe_interrupts(struct efx_nic *efx) efx->n_channels = 1 + (efx_separate_tx_channels ? 1 : 0); efx->n_rx_channels = 1; efx->n_tx_channels = 1; - efx->tx_channel_offset = 1; + efx->tx_channel_offset = efx_separate_tx_channels ? 1 : 0; efx->n_xdp_channels = 0; efx->xdp_channel_offset = efx->n_channels; efx->legacy_irq = efx->pci_dev->irq; -- cgit v1.2.3