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| author | Linus Torvalds <torvalds@linux-foundation.org> | 2018-02-03 01:57:44 +0300 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2018-02-03 01:57:44 +0300 |
| commit | d3581c8ef718ae1b03e9106446ddf76b77026895 (patch) | |
| tree | bf8f1bb5afc691f7681cf7c79515c726127fd04c | |
| parent | ef991796be0e65b644fe60198bd1112830eff173 (diff) | |
| parent | 188775181bc05f29372b305ef96485840e351fde (diff) | |
| download | linux-d3581c8ef718ae1b03e9106446ddf76b77026895.tar.xz | |
Merge tag 'firewire-updates' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394
Pull firewire updates from Stefan Richter
- make JMicron JMB38x controllers work with IOMMU-equipped systems
- IP-over-1394: allow user-configured MTU of up to 4096 bytes
* tag 'firewire-updates' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394:
firewire-ohci: work around oversized DMA reads on JMicron controllers
firewire: net: max MTU off by one
| -rw-r--r-- | drivers/firewire/net.c | 7 | ||||
| -rw-r--r-- | drivers/firewire/ohci.c | 8 |
2 files changed, 13 insertions, 2 deletions
diff --git a/drivers/firewire/net.c b/drivers/firewire/net.c index 242359c2d1f1..60e75e6d9104 100644 --- a/drivers/firewire/net.c +++ b/drivers/firewire/net.c @@ -1480,9 +1480,14 @@ static int fwnet_probe(struct fw_unit *unit, goto out; dev->local_fifo = dev->handler.offset; + /* + * default MTU: RFC 2734 cl. 4, RFC 3146 cl. 4 + * maximum MTU: RFC 2734 cl. 4.2, fragment encapsulation header's + * maximum possible datagram_size + 1 = 0xfff + 1 + */ net->mtu = 1500U; net->min_mtu = ETH_MIN_MTU; - net->max_mtu = 0xfff; + net->max_mtu = 4096U; /* Set our hardware address while we're at it */ ha = (union fwnet_hwaddr *)net->dev_addr; diff --git a/drivers/firewire/ohci.c b/drivers/firewire/ohci.c index ccf52368a073..45c048751f3b 100644 --- a/drivers/firewire/ohci.c +++ b/drivers/firewire/ohci.c @@ -1128,7 +1128,13 @@ static int context_add_buffer(struct context *ctx) return -ENOMEM; offset = (void *)&desc->buffer - (void *)desc; - desc->buffer_size = PAGE_SIZE - offset; + /* + * Some controllers, like JMicron ones, always issue 0x20-byte DMA reads + * for descriptors, even 0x10-byte ones. This can cause page faults when + * an IOMMU is in use and the oversized read crosses a page boundary. + * Work around this by always leaving at least 0x10 bytes of padding. + */ + desc->buffer_size = PAGE_SIZE - offset - 0x10; desc->buffer_bus = bus_addr + offset; desc->used = 0; |