of this micro-optimization occurs when we call pmap_enter() to wire an
already mapped page. Because of the micro-optimization, we fail to
mark the PTE as wired. Later, on teardown of the address space,
pmap_remove_pages() destroys the PTE before vm_fault_unwire() has
unwired the page. (pmap_remove_pages() is not supposed to destroy
wired PTEs. They are destroyed by a later call to pmap_remove().)
Thus, the page becomes lost.
Note: The page is not lost if the application called munlock(2), only
if it relies on teardown of the address space to unwire its pages.
For the historically inclined, this bug was introduced by a
megacommit, revision 1.182, roughly six years ago.
Leak observed by: green@ and dillon independently
Patch submitted by: dillon at backplane dot com
Reviewed by: tegge@
MFC after: 1 week
correct. Instead, check it against the possible settings (_PRS) when
the link is probed. This is important when using APIC mode but link
devices still have PIC mode settings. This is also what Linux does.
Additional prodding by: Len Brown len dot brown at intel dot com
based on the destination sleep state. Add a method to restore the old
state on resume. This is needed for the case of suspending to a very low
state disabling a GPE (i.e. S4), resuming, and then suspending to a higher
state (i.e. S3). This case should now keep the proper GPEs enabled.
device can wake the system. For example:
dev.root0.nexus0.acpi0.acpi_lid0.wake: 1
dev.root0.nexus0.acpi0.acpi_button0.wake: 1
dev.root0.nexus0.acpi0.pcib0.wake: 0
dev.root0.nexus0.acpi0.sio0.wake: 0
been developed for use with FreeBSD, version 4.8 and later.
Submitted by: Hema Joyce
Reviewed by: Prafulla Deuskar
Approved by: Prafulla Deuskar
MFC after: 1 week
subsystem lock to avoid tripping over an assertion regarding whether
the lock is held or not. This is likely to be the cause of a panic
tripped over by Andrea Campi.
acpi_wake_init:
Evaluate _PRW and set the GPE type
acpi_wake_set_enable:
Enable or disable a device's GPE.
acpi_wake_sleep_prep:
Perform any last-minute changes to the device to prepare it for
entering the given sleep state.
Also, walk the entire namespace when transitioning to a sleep state,
disabling any GPEs which aren't appropriate for the given state. Transition
acpi_lid and acpi_button to the new API.
This clears the way for non-ACPI-aware devices to wake the system (i.e.
modems) and fixes a problem where systems power up after shutdown when a
GPE is triggered.
In particular, disabling it was likely to break configurations
involving ng_vlan(4) since the latter couldn't control
the parent's VLAN_MTU in the way vlan(4) did.
Pointed out by: ru
does not reliably prevent the triggering of interrupts for all supported
configurations. Thus, the FIFO size probe could cause an interrupt,
which could lead to an interrupt storm in the shared interrupt case.
To prevent this, change ns8250_bus_probe() to use the overflow bit in
the line status register instead of the RX ready bit in the interrupt
identification register to detect whether the FIFO has filled up.
This allows us to clear all bits in the interrupt enable register during
the probe, which should prevent interrupts reliably.
Additionally, the detected FIFO size may be a bit more accurate, because
the overflow bit is only set when the FIFO did actually fill up, while
interrupts would trigger a bit early.
Reviewed and tested on a lot of hardware by: marcel
struct vmspace is freed from cpu_sched_exit() to pmap_release().
This has the advantage of being able to rely on MI code to decide
when a free should occur, instead of having to inspect the reference
count ourselves.
At the same time, turn the per-CPU vmspace pointer into a pmap pointer,
so that pmap_release() can deal with pmaps exclusively.
Reviewed (and embrassing bug spotted) by: jake
gmon and struct gmonhdr was originally just to represent the kernel
(profiling) clock frequency and it remains poorly suited to representing
the frequencies of fast counters like the TSC. It broke a year or two
ago. This quick fix keeps it working for another year or month or two
until TSC frequencies can exceed 2^32, by dividing the frequency by 2.
Dividing the frequency by 4 would work for a little longer but would
lose a little too much precision.
Fixed profiling of trap, syscall and interrupt handlers and some
ordinary functions, essentially by backing out half of rev.1.106 of
i386/exception.s. The handlers must be between certain labels for
the purposes of profiling, and this was broken by scattering them in
separately compiled .s files, especially for ordinary functions that
ended up between the labels. Merge the files by #including them as
before, except with different pathnames and better comments and
organization. Changes to the scattered files are minimal -- just
move the labels to the file that does the #includes.
This also partly fixes profiling of IPIs -- all IPI handlers are now
correctly classified as interrupt handlers, but many are still missing
mcount calls.
vm86bios.s is included as before, but it is now between the labels for
interrupt handlers again, which seems to be wrong since half of it is
for a non-interrupt handler.
converts miidevs to a .h file, so rename to reflect that.
The usb and pccard versions have also been renamed and will be hooked
into the build system shortly (I've made the conversion in my p4
tree).
