Hi,
Booting 4.20 on SolidRun Clearfog reliably provokes the following
warning - this is with mvneta built in, but DSA as modules:
WARNING: CPU: 0 PID: 555 at kernel/dma/debug.c:1230 check_sync+0x514/0x5bc
mvneta f1070000.ethernet: DMA-API: device driver tries to sync DMA memory it
has not allocated [device address=0x000000002dd7dc00] [size=240 bytes]
Modules linked in: ahci mv88e6xxx dsa_core xhci_plat_hcd xhci_hcd devlink
armada_thermal marvell_cesa des_generic ehci_orion phy_armada38x_comphy mcp3021
spi_orion evbug sfp mdio_i2c ip_tables x_tables
CPU: 0 PID: 555 Comm: bridge-network- Not tainted 4.20.0+ #291
Hardware name: Marvell Armada 380/385 (Device Tree)
[<c0019638>] (unwind_backtrace) from [<c0014888>] (show_stack+0x10/0x14)
[<c0014888>] (show_stack) from [<c07f54e0>] (dump_stack+0x9c/0xd4)
[<c07f54e0>] (dump_stack) from [<c00312bc>] (__warn+0xf8/0x124)
[<c00312bc>] (__warn) from [<c00313b0>] (warn_slowpath_fmt+0x38/0x48)
[<c00313b0>] (warn_slowpath_fmt) from [<c00b0370>] (check_sync+0x514/0x5bc)
[<c00b0370>] (check_sync) from [<c00b04f8>]
(debug_dma_sync_single_range_for_cpu+0x6c/0x74)
[<c00b04f8>] (debug_dma_sync_single_range_for_cpu) from [<c051bd14>]
(mvneta_poll+0x298/0xf58)
[<c051bd14>] (mvneta_poll) from [<c0656194>] (net_rx_action+0x128/0x424)
[<c0656194>] (net_rx_action) from [<c000a230>] (__do_softirq+0xf0/0x540)
[<c000a230>] (__do_softirq) from [<c00386e0>] (irq_exit+0x124/0x144)
[<c00386e0>] (irq_exit) from [<c009b5e0>] (__handle_domain_irq+0x58/0xb0)
[<c009b5e0>] (__handle_domain_irq) from [<c03a63c4>] (gic_handle_irq+0x48/0x98)
[<c03a63c4>] (gic_handle_irq) from [<c0009a10>] (__irq_svc+0x70/0x98)
...
This appears to be from:
if (rx_bytes <= rx_copybreak) {
/* better copy a small frame and not unmap the DMA
region */
skb = netdev_alloc_skb_ip_align(dev, rx_bytes);
if (unlikely(!skb))
goto err_drop_frame_ret_pool;
dma_sync_single_range_for_cpu(dev->dev.parent,
rx_desc->buf_phys_addr,
MVNETA_MH_SIZE +
NET_SKB_PAD,
rx_bytes,
DMA_FROM_DEVICE);
which suggests that rx_desc->buf_phys_addr is not something that should
be passed to dma_sync_single_range_for_cpu(). I've not been able to
track down why that is, nor which interface is provoking that.
As I don't have the details of how the buffer management hardware works
on Armada 388, I'm unable to debug this myself.
--
RMK's Patch system: https://www.armlinux.org.uk/developer/patches/
FTTC broadband for 0.8mile line in suburbia: sync at 12.1Mbps down 622kbps up
According to speedtest.net: 11.9Mbps down 500kbps up
