the new raspberry pi 4 firmware for arm64 seems to have
broken atag support. so we now parse the device tree
structure to get the bootargs and memory configuration.
Ori Bernstein had Sunrise Point-H USB 3.0 xHCI Controller that would mysteriously
crash on the 5th ENABLESLOT command. This was reproducable by even just allocating
slots in a loop right after init.
It turns out, the 1.2 spec extended the Max Scratchpad Buffers in HCSPARAMS2 so our
driver would not allocate enougth scratchpad buffers and controller firmware would
crash once it went beyond our allocated scratchpad buffer array.
This change also fixes:
- ignore bits 16:31 in PAGESIZE register
- preserve bits 10:31 in the CONFIG register
- handle ADDESSDEV command failure (so it can be retried)
preallocate 2% of user pages for page tables and MMU structures
and keep them mapped in the VMAP range. this leaves more space
in the KZERO window and avoids running out of kernel memory on
machines with large amounts of memory.
always clean AND invalidate caches before dma read,
never just invalidate as the buffer might not be
aligned to cache lines...
we have to invalidate caches again *AFTER* the dma
read has completed. the processor can bring in data
speculatively into the cache while the dma in in
flight.
we override atag memory on reboot, so preserve
the memsize learned from atag as *maxmem plan9
variable. the global memsize variable is not
needed anymore.
avoid trashing the following atag when zero
terminating the cmdline string.
zero memory after plan9.ini variables.
the Ipselftab is designed to not require locking on read
operation. locking the selftab in ipselftabread() risks
deadlock when accessing the user buffer creates a fault.
remove unused fields from the Ipself struct.
initialize the rate limits when the device gets
bound, not when it is created. so that the
rate limtis get reset to default when the ifc
is reused.
adjust the burst delay when the mtu is changed.
this is to make sure that we allow at least one
full sized packet burst.
make a local copy of ifc->m before doing nil
check as it can change under us when we do
not have the ifc locked.
specify Ebound[] and Eunbound[] error strings
and use them consistently.
remove references to the unused Conv.car qlock.
ipifcregisterproxy() is called with the proxy
ifc wlock'd, which means we cannot acquire the
rwlock of the interfaces that will proxy for us
because it is allowed to rlock() multiple ifc's
in any order. to get arround this, we use canrlock()
and skip the interface when we cannot acquire the
lock.
the ifc should get wlock'd only when we are about
to modify the ifc or its lifc chain. that is when
adding or removing addresses. wlock is not required
when we addresses to the selfcache, which has its
own qlock.
mark reader process pointers with (void*)-1 to mean
not started yet. this avoids the race condition when
media unbind happens before the kproc has set its
Proc* pointer. then we would not post the note and
the reader would continue running after unbind.
etherbind can be simplified by reading the #lX/addr
file to get the mac address, avoiding the temporary
buffer.
when the exclusive monitor is cleared, a event is generated
which we can use to wake up idlehands. that way we do not
need to wait for the next timer interrupt until a cpu takes
work from the run queue.
we did not interpret the $rootdir and $rootspec environment
variables right. $rootdir is what gets bound to / (usually /root)
and $rootspec is the mountspec of /root.
i'v been seeing the error condition described above in the
Slowbulkin comment. so i'm enabling the work arround which
seems to fix the lockup.
in the split transaction case where we want to start the
transaction at frame start, acquire the ctlr lock *before*
checking if we are in the right frame number. so the start
will happen atomically. checking the software ctlr->sofchan
instead of checking the interrupt mask register seems to
be quicker.
setting the haint mask bit for the chan under ctlr lock
in chanio() instead of chanwait() avoids needing to acquire
the ctlr lock twice.
mask wakechan bits with busychan bitmap in interrupt handlers
so we will not try to wake up released chans by accident.
sleep() and tsleep() might get interrupted so we have to
release the split qlock in the split transaction case and
in all cases, make sure to halt the channel before release.
add some common debug functions to dump channel and controller
registers.
we have to ensure that all stores saving the process state
have completed before setting up->mach = nil in the scheduler.
otherwise, another cpu could observe up->mach == nil while
the stores such as the processes p->sched label have not finnished.
attached is a patch to fix receive in the 8169 chip on my thinkpad
A485. i'm not sure why, but the same thing was done in 3d56a0fc4645
for Macv45.
nick
some control transactions can confuse the xhci controller so
much that it even fails to respond to command abort or STOPEP
control command. with no way for us to abort the transaction
but a full controller reset.
we give the controller 5 seconds to abort our initial
transaction and if that fails we wake the recover process
to reset the controller.
thanks mischief for testing.
the temporary stack segment used to be at a fixed address above or
below the user stack. these days, the temp stack is mapped dynamically
by sysexec so TSTKTOP is obsolete.
between being commited to a machno and having acquired the lock, the
scheduler could come in an schedule us on a different processor. the
solution is to have dtmachlock() take a special -1 argument to mean
"current mach" and return the actual mach number after the lock has
been acquired and interrupts being disabled.
using ~IP_DF mask to select offset and "more fragments" bits
includes the evil bit 15. so instead define a constant IP_FO
for the fragment offset bits and use (IP_MF|IP_FO). that way
the evil bit gets ignored and doesnt cause any useless calls
to ipreassemble().
tested on a t43 with igfx and a 1600x1200 t43p screen
what works: lvds, blanking
what doesn't: hwgc (not visible), snarfing edid
untested: vga
based on realemu traces.
unfraglen() had the side effect that it would always copy the
nexthdr field from the fragment header to the previous nexthdr
field. this is fine when we reassemble packets but breaks
fragments that we want to just forward unchanged.
given that we now keep the block size consistent with the
ip packet size, the variable header part of the ip packet
is just: BLEN(bp) - fp->flen == fp->hlen.
fix bug in ip6reassemble() in the non-fragmented case:
reload ih after ip header was moved before writing ih->ploadlen.
use concatbloc() instead of pullupblock().
some protocols assume that Ip4hdr.length[] and Ip6hdr.ploadlen[]
are valid and not out of range within the block but this has
not been verified. also, the ipv4 and ipv6 headers can have variable
length options, which was not considered in the fragmentation and
reassembly code.
to make this sane, ipiput4() and ipiput6() now verify that everything
is in range and trims to block to the expected size before it does
any further processing. now blocklen() and Ip4hdr.length[] are conistent.
ipoput4() and ipoput6() are simpler now, as they can rely on
blocklen() only, not having a special routing case.
ip fragmentation reassembly has to consider that fragments could
arrive with different ip header options, so we store the header+option
size in new Ipfrag.hlen field.
unfraglen() has to make sure not to run past the buffer, and hadle
the case when it encounters multiple fragment headers.
all screen implementations use a Memimage* internally
for the framebuffer, so we can return a shared reference
to its Memdata structure in attachscreen() instead of
a framebuffer data pointer.
this eleminates the softscreen == 0xa110c hack as we
always use shared Memdata* now.
Under the normal close sequence, when we receive a FIN|ACK, we enter
TIME-WAIT and respond to that LAST-ACK with an ACK. Our TCP stack would
send an ACK in response to *any* ACK, which included FIN|ACK but also
included regular ACKs. (Or PSH|ACKs, which is what we were actually
getting/sending).
That was more ACKs than is necessary and results in an endless ACK storm
if we were under the simultaneous close sequence. In that scenario,
both sides of a connection are in TIME-WAIT. Both sides receive
FIN|ACK, and both respond with an ACK. Then both sides receive *those*
ACKs, and respond again. This continues until the TIME-WAIT wait period
elapses and each side's TCP timers (in the Plan 9 / Akaros case) shut
down.
The fix for this is to only respond to a FIN|ACK when we are in TIME-WAIT.
always start the pager kproc in swapinit(), simplifying kickpager().
allow zero conf.nswap and conf.nswppo. avoid allocating the reference
map and iolist arrays in that case.
use ulong for ioptr and iolist indices.
don't panic when writing pages out to the swapfile fails. just
requeue the page in the io transaction list so we will try
again next time executeio() is run or just free the page when
the swap reference was dropped.
remove unused pagersummary() function.
