kernel.
When access restrictions are added to a page table entry, we flush the
corresponding virtual address mapping from the TLB. In contrast, when
access restrictions are removed from a page table entry, we do not
flush the virtual address mapping from the TLB. This is exactly as
recommended in AMD's documentation. In effect, when access
restrictions are removed from a page table entry, AMD's MMUs will
transparently refresh a stale TLB entry. In short, this saves us from
having to perform potentially costly TLB flushes. In contrast,
Intel's MMUs are allowed to generate a spurious page fault based upon
the stale TLB entry. Usually, such spurious page faults are handled
by vm_fault() without incident. However, when we are executing
no-fault sections of the kernel, we are not allowed to execute
vm_fault(). This change introduces special-case handling for spurious
page faults that occur in no-fault sections of the kernel.
In collaboration with: kib
Tested by: gibbs (an earlier version)
I would also like to acknowledge Hiroki Sato's assistance in
diagnosing this problem.
MFC after: 1 week
along with functions, SYSCTLs and tunables that are not used with
ATA_CAM in #ifndef ATA_CAM, similar to the existing #ifdef'ed ATA_CAM
code for the other way around. This makes it easier to understand
which parts of ata(4) actually are used in the new world order and
to later on remove the !ATA_CAM bits. It also makes it obvious that
there is something fishy with the C-bus front-end as well as in the
ATP850 support, as these used ATA_LOCKING which is defunct in the
ATA_CAM case. When fixing the former, ATA_LOCKING probably needs to
be brought back in some form or other.
Reviewed by: mav
MFC after: 1 week
inp_socket. To avoid panic, do not dereference inp_socket,
but obtain reuse port option from inp_flags2, like this
is done after next call to in_pcblookup_local() a few lines
down below.
Submitted by: rwatson
As of FreeBSD 8, this driver should not be used. Applications that use
posix_openpt(2) and openpty(3) use the pts(4) that is built into the
kernel unconditionally. If it turns out high profile depend on the
pty(4) module anyway, I'd rather get those fixed. So please report any
issues to me.
The pty(4) module is still available as a kernel module of course, so a
simple `kldload pty' can be used to run old-style pseudo-terminals.
no waiters, we still increase and decrease count in user mode without
entering kernel, once there is a waiter, sem_post will enter kernel to
increase count and wake thread up, this is atomicy and allow us to
gracefully destroy semaphore after sem_wait returned.
longer serve any purpose. Prior to r157446, they served a purpose
because there was a fixed amount of kernel virtual address space
reserved for pv entries at boot time. However, since that change pv
entries are accessed through the direct map, and so there is no limit
imposed by a fixed amount of kernel virtual address space.
Fix a couple of nearby style issues.
Reviewed by: jhb, kib
MFC after: 1 week
AcpiEnterSleepState() executes (optional) _GTS method since ACPICA 20120215
(r231844). To evaluate the method, we need malloc(9), which may sleep.
Reported by: bschmidt
MFC after: 3 days
Do not relocate twice an object which happens to be needed by loaded
binary (or dso) and some filtee opened due to symbol resolution when
relocating need objects. Record the state of the relocation
processing in Obj_Entry and short-circuit relocate_objects() if
current object already processed.
Do not call constructors for filtees loaded during the early
relocation processing before image is initialized enough to run
user-provided code. Filtees are loaded using dlopen_object(), which
normally performs relocation and initialization. If filtee is
lazy-loaded during the relocation of dso needed by the main object,
dlopen_object() runs too earlier, when most runtime services are not
yet ready.
Postpone the constructors call to the time when main binary and
depended libraries constructors are run, passing the new flag
RTLD_LO_EARLY to dlopen_object(). Symbol lookups callers inform
symlook_* functions about early stage of initialization with
SYMLOOK_EARLY. Pass flags through all functions participating in
object relocation.
Use the opportunity and fix flags argument to find_symdef() in
arch-specific reloc.c to use proper name SYMLOOK_IN_PLT instead of
true, which happen to have the same numeric value.
Reported and tested by: theraven
Reviewed by: kan
MFC after: 2 weeks
Enable using the statically embedded blob from the kernel, if present. The KLD
loaded DTB takes precedence, but they are both recognized and handled in the
same way.
Submitted by: Lukasz Wojcik
Obtained from: Semihalf
MFC after: 1 week
is queued to the hardware.
Because multiple concurrent paths can execute ath_start(), multiple
concurrent paths can push frames into the software/hardware TX queue
and since preemption/interrupting can occur, there's the possibility
that a gap in time will occur between allocating the sequence number
and queuing it to the hardware.
Because of this, it's possible that a thread will have allocated a
sequence number and then be preempted by another thread doing the same.
If the second thread sneaks the frame into the BAW, the (earlier) sequence
number of the first frame will be now outside the BAW and will result
in the frame being constantly re-added to the tail of the queue.
There it will live until the sequence numbers cycle around again.
This also creates a hole in the RX BAW tracking which can also cause
issues.
This patch delays the sequence number allocation to occur only just before
the frame is going to be added to the BAW. I've been wanting to do this
anyway as part of a general code tidyup but I've not gotten around to it.
This fixes the PR.
However, it still makes it quite difficult to try and ensure in-order
queuing and dequeuing of frames. Since multiple copies of ath_start()
can be run at the same time (eg one TXing process thread, one TX completion
task/one RX task) the driver may end up having frames dequeued and pushed
into the hardware slightly/occasionally out of order.
And, to make matters more annoying, net80211 may have the same behaviour -
in the non-aggregation case, the TX code allocates sequence numbers
before it's thrown to the driver. I'll open another PR to investigate
this and potentially introduce some kind of final-pass TX serialisation
before frames are thrown to the hardware. It's also very likely worthwhile
adding some debugging code into ath(4) and net80211 to catch when/if this
does occur.
PR: kern/166190
segments.h to a new x86 segments.h.
Add __packed attribute to some structs (just to be sure).
Also make it clear that i386 GDT and LDT entries are used in ia64 code.
usr.sbin/dconschat/dconschat.c:163:65: error: format specifies type 'size_t' (aka 'unsigned int') but the argument has type 'off_t' (aka 'long long') [-Werror,-Wformat]
snprintf(buf, PAGE_SIZE, "\r\n[dconschat reset target(addr=0x%zx)...]\r\n", dc->reset);
~~^ ~~~~~~~~~
%llx
Silence this by casting dc->reset to intmax_t, and using the appropriate
length modifier. While here, wrap the line to a 80 character margin.
MFC after: 3 days
the following warning produced by clang trunk:
In file included from /usr/src/sbin/devd/devd.cc:91:
In file included from /usr/obj/usr/src/tmp/usr/include/c++/4.2/map:64:
/usr/obj/usr/src/tmp/usr/include/c++/4.2/bits/stl_tree.h:987:2: error: add explicit braces to avoid dangling else [-Werror,-Wdangling-else]
else
^
MFC after: 3 days
than 4GB. Specifically, the inlined version of 'ptoa' of the the 'int'
count of pages overflowed on 64-bit platforms. While here, change
vm_object_madvise() to accept two vm_pindex_t parameters (start and end)
rather than a (start, count) tuple to match other VM APIs as suggested
by alc@.
