work properly with single-stepping in a kernel debugger. Specifically,
these routines have always disabled interrupts before increasing the nesting
count and restored the prior state of interrupts after decreasing the nesting
count to avoid problems with a nested interrupt not disabling interrupts
when acquiring a spin lock. However, trap interrupts for single-stepping
can still occur even when interrupts are disabled. Now the saved state of
interrupts is not saved in the thread until after interrupts have been
disabled and the nesting count has been increased. Similarly, the saved
state from the thread cannot be read once the nesting count has been
decreased to zero. To fix this, use temporary variables to store interrupt
state and shuffle it between the thread's MD area and the appropriate
registers.
In cooperation with: bde
MFC after: 1 month
- Fix the loop count on detach (causing a panic on detaching a serial
dongle).
- Increase a buffer in case some driver want extra long tty device names
(postfixing the purpose of the tty for example, e.g. u3g.ppp).
notification. devd would stop evaluating at 'at' (not '<k>=<v>') and
hence prevent 'port=X' (and 'bus=<"on" string>) from making it into the
environment for the devd action.
Reviewed by: hselasky
MFC after: 2 weeks
It seems the terminfo library on some systems (OS X, Linux) may emit the
sequence \e[x to reset to default attributes. Apart from using the
zero-command, this escape sequence allows many more operations, such as
setting ANSI colors. I don't see this used anywhere, so this should be
sufficient for now.
This deficiency was spotted by the Debian GNU/kFreeBSD. They have their
own patch, which is slightly flawed in my opinion. I don't know why they
never reported this issue to us.
MFC after: 1 week
zones whose objects are larger than a page to use startup_alloc(). This
allows allocation of zone objects during early boot on machines with a large
number of CPUs since the resulting zone objects are larger than a page.
Submitted by: trema
Reviewed by: attilio
MFC after: 1 week
This could lead to a division by zero if hardware is multi-core and/or
multi-threaded, but for some (quite unusual) reason FreeBSD sees only
one logical processor. This could happen, for example, if neither MADT
nor MP Table are presented by BIOS.
Also:
- assert in topo_probe_0x4 that BSP is accounted for
- neither cpu_cores nor cpu_logical should be zero after successful
probing, so either being zero is an indication of failed probing
Reported by: vwe, Dan Allen <danallen46@airwired.net>
Tested by: Dan Allen <danallen46@airwired.net>
MFC after: 3 days
- hw.usb.ucom.cons_unit is now split into
hw.usb.ucom.cons_unit/...cons_subunit.
Note: The tunable/sysctl hw.usb.ucom.cons_unit needs to be reviewed if
a) a console was defined a USB serial devices, and a USB device with
more than 1 subunit is present, and this device is attached before the
device functioning as a console
or
b) a console was defined on a USB device with more than 1 subunit
Reviewed by: hps
MFC after: 2 weeks
only, and should be protected with an ifdef, and the no-execute bit in
32-bit set_user_sr() should be set before the comparison, not after, or
it will never match.
of the EV_DONE flag and use the mutex to protect against losing wakeups
in g_waitfor_event().
Reported by: davidxu
Tested by: davidxu
Discussed on: freebsd-current
set_user_sr() itself caches the user segment VSID, there is no need for
cpu_switch() to do it again. This change also unifies the 32 and 64-bit
code paths for kernel faults on user pages and remaps the user SLB slot
on 64-bit systems when taking a syscall to avoid some unnecessary segment
exception traps.
a shorter message (userland generally only sees the first 6 to 8
characters) when waiting for the allproc lock. Use "-" when idle to math
the behavior of other kthreads.
Reviewed by: attilio
MFC after: 1 week
- Use > 2^32 - 1 instead of >= when checking for memory regions above 4G.
- Skip SMAP entries > 4G on i386 rather than breaking out of the loop
since SMAP entries are not guaranteed to be in order.
- Remove 'i' and loop over 'rid' directly in the dump_avail[] case.
- Only check for 4G regions in the dump_avail[] case on i386 if PAE is
enabled since vm_paddr_t is 32-bit in the !PAE case.
Submitted by: alc
to amd64, i386, and pc98. The headers are installed to /usr/include/x86
during an installworld, and an 'x86' symlink is created for kernel builds
similar to 'machine' so that the headers can be included as <x86/foo.h>.
Reviewed by: imp
about but otherwise ignored. When allowing the master to be set manually via
ifconfig(8) by adding the former to IFM_SUBTYPE_ETHERNET_OPTION_DESCRIPTIONS
(as it should be) it seems to be unfavorable that a machine can be made to
panic with a simple ifconfig(8) invocation.
concurrency bug. Since all SLB/SR entries were invalidated during an
exception, a decrementer exception could cause the user segment to be
invalidated during a copyin()/copyout() without a thread switch that
would cause it to be restored from the PCB, potentially causing the
operation to continue on invalid memory. This is now handled by explicit
restoration of segment 12 from the PCB on 32-bit systems and a check in
the Data Segment Exception handler on 64-bit.
While here, cause copyin()/copyout() to check whether the requested
user segment is already installed, saving some pipeline flushes, and
fix the synchronization primitives around the mtsr and slbmte
instructions to prevent accessing stale segments.
MFC after: 2 weeks
feature_present(3) checks.
This will help to run-time detect and conditionally handle specific
optionas of either feature in user space (i.e. in libipsec).
Descriptions read by: rwatson
MFC after: 2 weeks
