. phys_copy() (taken from memcpy) can legitimately
cause pagefaults below the source/dest address due
to word-alignment
Change-Id: Ibee8f069781d16caea671246c021fb17a2a892b1
Interrupts where not correctly masked while in kernel, which
breaks one of the current main assumptions.
Also remove some duplication on ARM asm files, and add a function
to check the status of ARM irqs (not compiled by default)
Change-Id: I3c25d2b388f93fd8fe423998b94b3c4f140ba831
. the total amount of memory in the system didn't include the memory
used by the boot-time modules and some dynamic allocation by the
kernel at boot time (to map in VM). especially apparent on our
ARM board with 'only' 512MB of memory and a huge ramdisk.
. also: *add* the VM loaded module to the freelist after it has
been allocated for & mapped in instead of cutting it *out* of the
freelist! so we get a few more MB free..
Change-Id: If37ac32b21c9d38610830e21421264da4f20bc4f
. raise(SIGFPE) for modulo-0/divide-0 operations in
internal int division functions
. gcc: do not link with -lgcc anywhere so these internal
functions are always used from libc instead of (sometimes)
masked by -lgcc
. together fixes test53 on ARM
Change-Id: I31ec19dfdd68b8a92695595da901874e63106f9d
. set MF_CONTEXT_SET after signal handler state
is set so it doesn't get clobbered by the kernel
afterwards (i.e. by delivermsg()).
fixes at least test41.
Change-Id: I7e5e0e9311c8bbc1c0a9c7ca466ceddd9edfa03f
if an exec() fails partway through reading in the sections, the target
process is already gone and a defunct process remains. sanity checking
the binary beforehand helps that.
test10 mutilates binaries and exec()s them on purpose; making an exec()
fail cleanly in such cases seems like acceptable behaviour.
fixes test10 on ARM.
Change-Id: I1ed9bb200ce469d4d349073cadccad5503b2fcb0
. kernel: signal handler args for ARM
. kernel: sanity check return address (LSB indicates thumb mode)
. libc: properly retrieve signal mask for ARM
together fix test37 on ARM.
Change-Id: I4e00f754c50104ed85c7fdf8ec5ad54568f20a81
The Cycle CouNTer on ARM cannot be used reliably as it wraps around
rather quickly and can be altered by user space (on Minix). Furthermore,
it's buggy when wrapping and is not implemented at all on the Linaro
Beagleboard emulator.
This patch programs GPTIMER10 as a free running clock at 1.625 MHz (it
doesn't generate interrupts). It's memory mapped into every process,
which enables libsys to provide micro_delay().
Change-Id: Iba004c6c62976762fe154ea390d69e518eec1531
A few kernel and calling convention adjustments to make sigsend and
sigreturn work for arm.
. provide a arch_proc_setcontext for earm in kernel
. set LR in context of signal handler to provide a proper
return address (to __sigreturn)
. change __sigreturn to retrieve the sigcontext pointer
from the sigframe struct and pass it to _sigreturn() in r0
Change-Id: Icd135a70595382c79d11d8dd9876f6a6f1df41f8
Due to the ABI we are using we have to use the earm architecture
moniker for the build system to behave correctly. This involves
then some headers to move around.
There is also a few related Makefile updates as well as minor
source code corrections.
* Updating common/lib
* Updating lib/csu
* Updating lib/libc
* Updating libexec/ld.elf_so
* Corrected test on __minix in featuretest to actually follow the
meaning of the comment.
* Cleaned up _REENTRANT-related defintions.
* Disabled -D_REENTRANT for libfetch
* Removing some unneeded __NBSD_LIBC defines and tests
Change-Id: Ic1394baef74d11b9f86b312f5ff4bbc3cbf72ce2
The GPTIMER1 clock is configured to run at 32 kHz and generate
(overflow) interrupts every 1 ms. However, the Timer Overflow Wrappping
Register (TOWR) was configured to filter every other interrupt. This
caused to the internal 'realtime' value to be off.
. restore state depends on how saving of state was done;
also remember trap style in sig context
. actually set and restore TRACEBIT with new trap styles;
have to remove it once process enters kernel though, done
in debug trap exception handler
. introduce MF_STEP that makes arch-specific code
turn on trace bit instead of setting TRACEBIT directly,
a bit more arch-friendly and avoids keeping precious
state in per-process PSW arch-dependently
state is usually not in p_reg any more with sysenter/syscall trap entries,
so when saving/restarting do_ipc invocations the state has to be remembered
explicitly.
The 'trap style' variable records how a process has trapped into the
kernel (hardware/software interrupt, or one of the other trap
instructions). KTS_NONE indicates the process isn't trapped into the
kernel at all and is useful for sanity checking. The KTS_NONE reset was
inadvertently removed while removing some debugging code and this commit
restores it.
When processes have entered the kernel with one of the new
trap modes, %ebp is not valid, used for stacktraces, so we
need an alternative way to retrieve it to make the stacktraces
valid again.
upgrade to NetBSD CVS release from 2012/10/17 12:00:00 UTC
Makefiles updates to imporve portability
Made sure to be consistent in the usage of braces/parenthesis at
least on a per file basis. For variables, it is recommended to
continue to use braces.
The tested targets are the followgin ones:
* tools
* distribution
* sets
* release
The remaining NetBSD targets have not been disabled nor tested
*at all*. Try them at your own risk, they may reboot the earth.
For all compliant Makefiles, objects and generated files are put in
MAKEOBJDIR, which means you can now keep objects between two branch
switching. Same for DESTDIR, please refer to build.sh options.
Regarding new or modifications of Makefiles a few things:
* Read share/mk/bsd.README
* If you add a subdirectory, add a Makefile in it, and have it called
by the parent through the SUBDIR variable.
* Do not add arbitrary inclusion which crosses to another branch of
the hierarchy; If you can't do without it, put a comment on why.
If possible, do not use inclusion at all.
* Use as much as possible the infrastructure, it is here to make
life easier, do not fight it.
Sets and package are now used to track files.
We have one set called "minix", composed of one package called "minix-sys"
Bumping libc files for unsupported architectures, to simplify merging.
A bunch of small fixes:
* in libutil update
* the macro in endian.h
* some undefined types due to clear separation from host.
* Fix a warning for cdbr.c
Some modification which were required for the new build system:
* inclusion path for const.h in sconst, still hacky
* Removed default malloc.c which conflicts on some occasions.
. Check if we have the right number of boot modules
. Check if the ELF parsing of VM actually succeeded
Both these are root causes of less-than-obvious other
errors/asserts a little further down the line; uncovered
while experimenting with booting by iPXE, specifically
(a) iPXE having a 8-multiboot-modules limit and
(b) trying to boot a gzipped VM.
. add cpufeature detection of both
. use it for both ipc and kernelcall traps, using a register
for call number
. SYSENTER/SYSCALL does not save any context, therefore userland
has to save it
. to accomodate multiple kernel entry/exit types, the entry
type is recorded in the process struct. hitherto all types
were interrupt (soft int, exception, hard int); now SYSENTER/SYSCALL
is new, with the difference that context is not fully restored
from proc struct when running the process again. this can't be
done as some information is missing.
. complication: cases in which the kernel has to fully change
process context (i.e. sigreturn). in that case the exit type
is changed from SYSENTER/SYSEXIT to soft-int (i.e. iret) and
context is fully restored from the proc struct. this does mean
the PC and SP must change, as the sysenter/sysexit userland code
will otherwise try to restore its own context. this is true in the
sigreturn case.
. override all usage by setting libc_ipc=1
. only reference single pages in process data structures
to simplify page faults, copy-on-write, etc.
. this breaks the secondary cache for objects that are
not one-page-sized; restored in a next commit
Coverity was flagging a recursive include between kernel.h and
cpulocals.h. As cpulocals.h also included proc.h, we can move that
include statement into kernel.h, and clean up the source files'
include statements accordingly.
. map all objects named usermapped_*.o with globally visible
pages; usermapped_glo_*.o with the VM 'global' bit on, i.e.
permanently in tlb (very scarce resource!)
. added kinfo, machine, kmessages and loadinfo for a start
. modified log, tty to make use of the shared messages struct
. some strncpy/strcpy to strlcpy conversions
. new <minix/param.h> to avoid including other minix headers
that have colliding definitions with library and commands code,
causing parse warnings
. removed some dead code / assignments
adjust the smp booting procedure for segmentless operation. changes are
mostly due to gdt/idt being dependent on paging, because of the high
location, and paging being on much sooner because of that too.
also smaller fixes: redefine DESC_SIZE, fix kernel makefile variable name
(crosscompiling), some null pointer checks that trap now because of a
sparser pagetable, acpi sanity checking
This commit removes all traces of Minix segments (the text/data/stack
memory map abstraction in the kernel) and significance of Intel segments
(hardware segments like CS, DS that add offsets to all addressing before
page table translation). This ultimately simplifies the memory layout
and addressing and makes the same layout possible on non-Intel
architectures.
There are only two types of addresses in the world now: virtual
and physical; even the kernel and processes have the same virtual
address space. Kernel and user processes can be distinguished at a
glance as processes won't use 0xF0000000 and above.
No static pre-allocated memory sizes exist any more.
Changes to booting:
. The pre_init.c leaves the kernel and modules exactly as
they were left by the bootloader in physical memory
. The kernel starts running using physical addressing,
loaded at a fixed location given in its linker script by the
bootloader. All code and data in this phase are linked to
this fixed low location.
. It makes a bootstrap pagetable to map itself to a
fixed high location (also in linker script) and jumps to
the high address. All code and data then use this high addressing.
. All code/data symbols linked at the low addresses is prefixed by
an objcopy step with __k_unpaged_*, so that that code cannot
reference highly-linked symbols (which aren't valid yet) or vice
versa (symbols that aren't valid any more).
. The two addressing modes are separated in the linker script by
collecting the unpaged_*.o objects and linking them with low
addresses, and linking the rest high. Some objects are linked
twice, once low and once high.
. The bootstrap phase passes a lot of information (e.g. free memory
list, physical location of the modules, etc.) using the kinfo
struct.
. After this bootstrap the low-linked part is freed.
. The kernel maps in VM into the bootstrap page table so that VM can
begin executing. Its first job is to make page tables for all other
boot processes. So VM runs before RS, and RS gets a fully dynamic,
VM-managed address space. VM gets its privilege info from RS as usual
but that happens after RS starts running.
. Both the kernel loading VM and VM organizing boot processes happen
using the libexec logic. This removes the last reason for VM to
still know much about exec() and vm/exec.c is gone.
Further Implementation:
. All segments are based at 0 and have a 4 GB limit.
. The kernel is mapped in at the top of the virtual address
space so as not to constrain the user processes.
. Processes do not use segments from the LDT at all; there are
no segments in the LDT any more, so no LLDT is needed.
. The Minix segments T/D/S are gone and so none of the
user-space or in-kernel copy functions use them. The copy
functions use a process endpoint of NONE to realize it's
a physical address, virtual otherwise.
. The umap call only makes sense to translate a virtual address
to a physical address now.
. Segments-related calls like newmap and alloc_segments are gone.
. All segments-related translation in VM is gone (vir2map etc).
. Initialization in VM is simpler as no moving around is necessary.
. VM and all other boot processes can be linked wherever they wish
and will be mapped in at the right location by the kernel and VM
respectively.
Other changes:
. The multiboot code is less special: it does not use mb_print
for its diagnostics any more but uses printf() as normal, saving
the output into the diagnostics buffer, only printing to the
screen using the direct print functions if a panic() occurs.
. The multiboot code uses the flexible 'free memory map list'
style to receive the list of free memory if available.
. The kernel determines the memory layout of the processes to
a degree: it tells VM where the kernel starts and ends and
where the kernel wants the top of the process to be. VM then
uses this entire range, i.e. the stack is right at the top,
and mmap()ped bits of memory are placed below that downwards,
and the break grows upwards.
Other Consequences:
. Every process gets its own page table as address spaces
can't be separated any more by segments.
. As all segments are 0-based, there is no distinction between
virtual and linear addresses, nor between userspace and
kernel addresses.
. Less work is done when context switching, leading to a net
performance increase. (8% faster on my machine for 'make servers'.)
. The layout and configuration of the GDT makes sysenter and syscall
possible.
. sys_vircopy always uses D for both src and dst
. sys_physcopy uses PHYS_SEG if and only if corresponding
endpoint is NONE, so we can derive the mode (PHYS_SEG or D)
from the endpoint arg in the kernel, dropping the seg args
. fields in msg still filled in for backwards compatability,
using same NONE-logic in the library
. all invocations were S or D, so can safely be dropped
to prepare for the segmentless world
. still assign D to the SCP_SEG field in the message
to make previous kernels usable
. new mode for sys_memset: include process so memset can be
done in physical or virtual address space.
. add a mode to mmap() that lets a process allocate uninitialized
memory.
. this allows an exec()er (RS, VFS, etc.) to request uninitialized
memory from VM and selectively clear the ranges that don't come
from a file, leaving no uninitialized memory left for the process
to see.
. use callbacks for clearing the process, clearing memory in the
process, and copying into the process; so that the libexec code
can be used from rs, vfs, and in the future, kernel (to load vm)
and vm (to load boot-time processes)
. make exec() callers (i.e. vfs and rs) determine the
memory layout by explicitly reserving regions using
mmap() calls on behalf of the exec()ing process,
i.e. handling all of the exec logic, thereby eliminating
all special exec() knowledge from VM.
. the new procedure is: clear the exec()ing process
first, then call third-party mmap()s to reserve memory, then
copy the executable file section contents in, all using callbacks
tailored to the caller's way of starting an executable
. i.e. no more explicit EXEC_NEWMEM-style calls in PM or VM
as with rigid 2-section arguments
. this naturally allows generalizing exec() by simply loading
all ELF sections
. drop/merge of lots of duplicate exec() code into libexec
. not copying the code sections to vfs and into the executable
again is a measurable performance improvement (about 3.3% faster
for 'make' in src/servers/)
. readbios call is now a physical copy with range check in
the kernel call instead of BIOS_SEG+umap_bios
. requires all access to physical memory in bios range to go
through sys_readbios
. drivers/dpeth: wasn't using it
. adjusted printer
. generalize libexec slightly to get some more necessary information
from ELF files, e.g. the interpreter
. execute dynamically linked executables when exec()ed by VFS
. switch to netbsd variant of elf32.h exclusively, solves some
conflicting headers
patch my fdmanana:
As recommended by the Intel 64 and IA-32 Architectures Developer's
Manual Volume 3A, the GDT and IDT base addresses should be aligned on an
8 byte boundary to yield better processor performance.
. remove some call cycles by low-level functions invoking printf(); e.g.
send_sig() gets a return value that the caller should check
. reason: very-early-phase printf() would trigger a printf() causing
infinite recursion -> GPF
. move serial initialization a little earlier so DEBUG_EXTRA works for
serial earlier (e.g. its first instance, for "cstart")
. closes tracker item 583:
System Fails to Complete Startup with Verbose 2 and 3 Boot Parameters,
reported by Stephen Hatton / pikpik.
You might have to update the compiler-rt package! See UPDATING.
. the purpose of this -L was solely to find compiler-rt, which contains
runtime support code for clang-compiled binaries
. this also makes all other packaged libraries visible, however
. it is cleaner to isolate the base system from packages, and so
compiler-rt puts itself in /usr/pkg/compiler-rt/lib/ too, which the
base system henceforth uses exclusively
. e.g. this solves a link failure when libfetch is installed as a
package
. the new compiler-rt package also puts itself in /usr/pkg/lib for 'old'
systems; that is harmless. The benefit of 'new' systems is that the other
packages are hidden.
remove some old minix-userland-specific stuff
. /etc/ttytab as a file, and minix-compat function (fftyslot()),
replaced by /etc/ttys and new libc functions
. also remove minix-specific nlist(), cuserid(), fttyslot(), v8 regex
functions and <compat/regex.h>
. and remaining minix-only utilities that use them
. also unused <compat/pwd.h> and <compat/syslog.h> and
redundant <sys/sigcontext.h>
On the x86, saving FPU state has the side effect of resetting this
state. In some cases (fork, getcontext), this would cause the state
to be lost. This patch restores the FPU state right after saving it,
except when different state is loaded immediately after.
Previously, user processes could cause a kernel panic upon FPU state
restore, by passing bogus FPU state to the kernel (through e.g.
sigreturn). With this patch, the process is now sent a SIGFPE signal
instead.
There is important information about booting non-ack images in
docs/UPDATING. ack/aout-format images can't be built any more, and
booting clang/ELF-format ones is a little different. Updating to the
new boot monitor is recommended.
Changes in this commit:
. drop boot monitor -> allowing dropping ack support
. facility to copy ELF boot files to /boot so that old boot monitor
can still boot fairly easily, see UPDATING
. no more ack-format libraries -> single-case libraries
. some cleanup of OBJECT_FMT, COMPILER_TYPE, etc cases
. drop several ack toolchain commands, but not all support
commands (e.g. aal is gone but acksize is not yet).
. a few libc files moved to netbsd libc dir
. new /bin/date as minix date used code in libc/
. test compile fix
. harmonize includes
. /usr/lib is no longer special: without ack, /usr/lib plays no
kind of special bootstrapping role any more and bootstrapping
is done exclusively through packages, so releases depend even
less on the state of the machine making them now.
. rename nbsd_lib* to lib*
. reduce mtree
. we cannot use the boot monitor to print the system diag buffer
. for serial, we do nothing, just reset, everything is already printed
. for not-serial, we print the current diag buffer using direct video
memory access from the kernel
- this patch fixes a deadlock which may occur if we get a
spurious interrupt while calibrating clocks during the boot
time. Since we never handle interrupts while in the kernel
(BKL locked) the interrupt code locks the lock. This is a
different situation, a corner case, boot time only. We do not
return to userspace but to the kernel, so the BKL is not
unlocked. So we need irq handler which leaves the BKL
unlocked. The clock handler does it already, this patch adds
a dummy spurious irq handler for the same reason. It is better
to handle the situation this way to keep the normal runtime
code simple.
- this is a temporary change which makes images compiled for SMP
boot in SMP mode by default.
- this change is needed until we can configure the multiboot
images from the boot loader again.
User processes can send signals with number up to _NSIG. There are a few
signal numbers above that used by the kernel, but should explicitly not
be included in the range or range checks in PM will fail.
The system processes use a different version of sigaddset, sigdelset,
sigemptyset, sigfillset, and sigismember which does not include a range
check on signal numbers (as opposed to the normal functions used by normal
processes).
This patch unbreaks test37 when the boot image is compiled with GCC/Clang.
- we must not deliver messages from/to unstable address spaces.
In such a case, we must postpone the delivery. To make sute
that a process which is expecting an asynchronous message does
not starve, we must remember that we skipped delivery of some
messages and we must try to deliver again once the source
address space is stable again.
- when kernel copies from userspace, it must be sure that the TLB
entries are not stale and thus the referenced memory is correct
- everytime we change a process' address space we set p_stale_tlb
bits for all CPUs.
- Whenever a cpu finds its bit set when it wants to access the
process' memory, it refreshes the TLB
- it is more conservative than it needs to be but it has low
overhead than checking precisely
- two CPUs can issue IPI to each other now without any hazzard
- we must be able to handle synchronous scheduling IPIs from
other CPUs when we are waiting for attention from another one.
Otherwise we might livelock.
- necessary barriers to prevent reordering
- has_pending() takes a special argument that tells the code
whether we are scanning for asynchronous message or something
else.
- has_pending() is not used directly anymore
- the new functions are wrappings around has_pending() to make
the use more comfortable.
- these functions should become static inline eventually
Remove .ident sections, and force separations of .text and
.data sections into separate program headers, for the benefit
of the check done by MINIX boot monitor in multiboot mode.
