The cause of "Duplicate mbuf free panic" is in the programming
error of hme_load_txmbuf(). The code path of the panic is the
following.
1. Due to unknown reason DMA engine was freezed. So TX descritors
of HME become full and the last failed attempt to transmit a
packet had set its associated mbuf address to hme_txdesc
structure. Also the failed packet is requeued into interface
queue structure in order to retrasmit it when there are more
available TX descritors.
2. Since DMA engine was freezed, if_timer starts to decrement its
counter. When if_timer expires it tries to reset HME. During
the reset phase, hme_meminit() is called and it frees all
associated mbuf with descriptors. The last failed mbuf is also
freed here.
3. After HME reset completed, HME starts to retransmit packets
by dequeing the first packet in interface queue.(Note! the
packet was already freed in hme_meminit()!)
4. When a TX completion interrupt is posted by the HME, driver
tries to free the successfylly transmitted mbuf. Since the
mbuf was freed in step2, now we get "Duplicate mbuf free panic".
However, the real cause is in DMA engine freeze. Since no fatal
errors reported via interrupts, there might be other cause of
the freeze. I tried hard to understand the cause of DMA engine
freeze but couldn't find any clues. It seems that the freeze
happens under very high network loads(e.g. 7.5-8.0 MB/s TX speed).
Though this fix is not enough to eliminate DMA engine freeze it's
better than panic.
Reported by: jhb via sparc64 ML
- Let hme_start()/hme_init() acquire lock and then call
hme_start_locked()/hme_init_locked() respectivly.
- Teardown interrupt handler before hme_detach().
- Remove IFF_NEEDSGIANT flag and mark interrupt handler INTR_MPSAFE.
- Set callout handler to CALLOUT_MPSAFE.
- Add locks in hme MII interface.
Reviewed by: jake
Tested by: Julian C. Dunn <jdunn at opentrend dot net>
MFC after: 2 weeks
Since HME doesn't compensate the checksum for UDP datagram which
can yield to 0x0, UDP transmit checksum offload is disabled by
default. The UDP Transmit checksum offload can be reactivated
by setting special link option link0 with ifconfig(8).
Approved by: jake (mentor)
Reviewed by: tmm
Tested by: Herve Boulouis <amon@sockar.homeip.net>
pass any traffic. Unfortunately this means no full-duplex link with auto-
negotiation on hme(4) using DP83840A PHYs again.
I really thought I had tested this also on a Netra t1 100...
This is part 2/2 of fixing autonegotiation on hme(4) using DP83840A PHYs.
It appears to also fix the occasional problems to establish a link on
hme(4) using LU6612 PHYs and shouldn't hurt on those using QS6612 PHYs.
Obtained from: NetBSD
and Rx frames up to 8191 octets, so it is perfectly capable of supporting
vlan(4)-style VLAN natively.
Thus, make it support VLAN `oversize' frames.
Reviewed by: tmm
if_xname, if_dname, and if_dunit. if_xname is the name of the interface
and if_dname/unit are the driver name and instance.
This change paves the way for interface renaming and enhanced pseudo
device creation and configuration symantics.
Approved By: re (in principle)
Reviewed By: njl, imp
Tested On: i386, amd64, sparc64
Obtained From: NetBSD (if_xname)
Add two new arguments to bus_dma_tag_create(): lockfunc and lockfuncarg.
Lockfunc allows a driver to provide a function for managing its locking
semantics while using busdma. At the moment, this is used for the
asynchronous busdma_swi and callback mechanism. Two lockfunc implementations
are provided: busdma_lock_mutex() performs standard mutex operations on the
mutex that is specified from lockfuncarg. dftl_lock() is a panic
implementation and is defaulted to when NULL, NULL are passed to
bus_dma_tag_create(). The only time that NULL, NULL should ever be used is
when the driver ensures that bus_dmamap_load() will not be deferred.
Drivers that do not provide their own locking can pass
busdma_lock_mutex,&Giant args in order to preserve the former behaviour.
sparc64 and powerpc do not provide real busdma_swi functions, so this is
largely a noop on those platforms. The busdma_swi on is64 is not properly
locked yet, so warnings will be emitted on this platform when busdma
callback deferrals happen.
If anyone gets panics or warnings from dflt_lock() being called, please
let me know right away.
Reviewed by: tmm, gibbs
- Remove NetBSD-style or-ed together BUS_DMASYNC operations, in some
cases relaxing the (intended) syncing operation a bit.
- Add syncs before reading the descriptor rings.
- Try to combine syncs where possible to avoid overhead.
- Sync all maps before unloading them.
from the hardware descriptors to avoid the overhead of having a DMA
map for each of them. Bump the number of hardware descriptors to 128,
and use half as many software descriptors for now.
Some minor cleanups.
o don't strip the Ethernet header from inbound packets; pass packets
up the stack intact (required significant changes to some drivers)
o reference common definitions in net/ethernet.h (e.g. ETHER_ALIGN)
o track ether_ifattach/ether_ifdetach API changes
o track bpf changes (use BPF_TAP and BPF_MTAP)
o track vlan changes (ifnet capabilities, revised processing scheme, etc.)
o use if_input to pass packets "up"
o call ether_ioctl for default handling of ioctls
Reviewed by: many
Approved by: re
- always reinitialize the rx descriptors, even if the mbuf is kept.
This should fix the hangs on ifconfig that were observed
- on an rx overflow, reinitialize the descriptor so that the interface
will not hang
- correct some bus_dmamap_sync() calls
- correct some debug messages
- some minor nits
- remove some useless code from the status change handler that was intended
to enable the the MII drivers for external phys; this is already done
during interface initialization, and the deleted code made some
assumptions about phy addresses that do not seem to hold true on newer
cards. This should get at least one of the two hmes of newer Netra t1
machines working.
- correct the interrupt resource allocation
- bump the number of RX descriptors, lower values cause promblems on some
machines
in most machines of the Sun Ultra series. This is a port of the NetBSD
driver which I enhanced to make use of the gather functionality and the
configurable RX buffer offset to avoid copying all received/sent packet
(instead, packets will be directly DMAd from mbuf chains and into mbuf
clusters now).
