prevents one from running eg clang built with debug; the new one is
arbitrary (equal to MAXDSIZ) and... well, should be quite future-proof.
Same fix might be applicable to other 64 bit architectures; I'll ask
their respective maintainers to make sure it won't break anything.
Reviewed by: kib
MFC after: 2 weeks
Sponsored by: DARPA, AFRL
Differential Revision: https://reviews.freebsd.org/D10758
A long long time ago the register keyword told the compiler to store
the corresponding variable in a CPU register, but it is not relevant
for any compiler used in the FreeBSD world today.
ANSIfy related prototypes while here.
Reviewed by: cem, jhb
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D10193
This was introduced in r290156. It's present in 11.0, but not any 10.x
release unless someone decided to MFC it.
It affects ordinary pages right above the DMAP limit, which is effectively
system memory rounded up to a 1 GB (3rd level superpage) boundary (or up to
a minimum of 4 GB, on small systems).
Reported by: vangyzen
Reviewed by: kib, alc
Sponsored by: Dell EMC Isilon
Differential Revision: https://reviews.freebsd.org/D4030
operation after processor is configured to allow all required
features.
In particular, NX must be enabled in EFER, otherwise load of page
table element with nx bit set causes reserved bit page fault. Since
malloc uses direct mapping for small allocations, in particular for
the suspension pcbs, and DMAP is nx after r316767, this commit tripped
fault on resume path.
Restore complete state of EFER while wakeup code is still executing
with custom page table, before calling resumectx, instead of trying to
guess which features might be needed before resumectx restored EFER on
its own.
Bisected and tested by: trasz
Sponsored by: The FreeBSD Foundation
MFC after: 2 weeks
in place. To do per-cpu stats, convert all fields that previously were
maintained in the vmmeters that sit in pcpus to counter(9).
- Since some vmmeter stats may be touched at very early stages of boot,
before we have set up UMA and we can do counter_u64_alloc(), provide an
early counter mechanism:
o Leave one spare uint64_t in struct pcpu, named pc_early_dummy_counter.
o Point counter(9) fields of vmmeter to pcpu[0].pc_early_dummy_counter,
so that at early stages of boot, before counters are allocated we already
point to a counter that can be safely written to.
o For sparc64 that required a whole dummy pcpu[MAXCPU] array.
Further related changes:
- Don't include vmmeter.h into pcpu.h.
- vm.stats.vm.v_swappgsout and vm.stats.vm.v_swappgsin changed to 64-bit,
to match kernel representation.
- struct vmmeter hidden under _KERNEL, and only vmstat(1) is an exclusion.
This is based on benno@'s 4-year old patch:
https://lists.freebsd.org/pipermail/freebsd-arch/2013-July/014471.html
Reviewed by: kib, gallatin, marius, lidl
Differential Revision: https://reviews.freebsd.org/D10156
Demotions preserve PG_NX, so it is enough to set nx bit for initial
lowest-level paging entries.
Suggested and reviewed by: alc
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
The MFC will include a compat definition of smp_no_rendevous_barrier()
that calls smp_no_rendezvous_barrier().
Reviewed by: gnn, kib
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D10313
- renaming l_ifreq::ifru_metric to l_ifreq::ifru_ivalue;
- adding a definition for ifr_ifindex which points to l_ifreq::ifru_ivalue.
A quick search indicates that Linux already got the above changes since 2.1.14.
Reviewed by: kib, marcel, dchagin
MFC after: 1 week
The change introduced a dependency between genassym.c and header files
generated from .m files, but that dependency is not specified in the
make files.
Also, the change could be not as useful as I thought it was.
Reported by: dchagin, Manfred Antar <null@pozo.com>, and many others
I fixed this in 1997, but the fix was over-engineered and fragile and
was broken in 2003 if not before. i386 parameters were copied to 8
other arches verbatim, mostly after they stopped working on i386, and
mostly without the large comment saying how the values were chosen on
i386. powerpc has a non-verbatim copy which just changes the uncritical
parameter and seems to add a sign extension bug to it.
Just treat negative offsets as offsets if they are no more negative than
-db_offset_max (default -64K), and remove all the broken parameters.
-64K is not very negative, but it is enough for frame and stack pointer
offsets since kernel stacks are small.
The over-engineering was mainly to go more negative than -64K for the
negative offset format, without affecting printing for more than a
single address.
Addresses in the top 64K of a (full 32-bit or 64-bit) address space
are now printed less well, but there aren't many interesting ones.
For arches that have many interesting ones very near the top (e.g.,
68k has interrupt vectors there), there would be no good limit for
the negative offset format and -64K is a good as anything.
The change is more intrusive than I would like because the feature
requires that a vector number is written to a special register.
Thus, now the vector number has to be provided to lapic_eoi().
It was readily available in the IO-APIC and MSI cases, but the IPI
handlers required more work.
Also, we now store the VMM IPI number in a global variable, so that it
is available to the justreturn handler for the same reason.
Reviewed by: kib
MFC after: 6 weeks
Differential Revision: https://reviews.freebsd.org/D9880
Long ago, perhaps only on i386, kernel text was mapped read-only and
it was necessary to change the mapping to read-write to set breakpoints
in kernel text. Other writes by ddb to kernel text were also allowed.
This write protection is harder to implement with 4MB pages, and was
lost even for 4K pages when 4MB pages were implemented. So changing
the mapping became useless. It was actually worse than useless since
it followed followed various null and otherwise garbage pointers to
not change random memory instead of the mapping. (On i386s, the
pointers became good in pmap_bootstrap(), and on amd64 the pointers
became bad in pmap_bootstrap() if not before.)
Another bug broke detection of following of null pointers on i386,
except early in boot where not detecting this was a feature. When
I fixed the bug, I accidentally broke the feature and soon got traps
in db_write_bytes(). Setting breakpoints early in ddb was broken.
kib pointed out that a clean way to do the adjustment would be to use
a special [sub]map giving a small window on the bytes to be written.
The trap handler didn't know how to fix up errors for pagefaults
accessing the map itself. Such errors rarely need fixups, since most
traps for the map are for the first access which is a read.
Reviewed by: kib
matches static binaries.
Interpretation of the 'static' there is that the binary must not
specify an interpreter. In particular, shared objects are matched by
the brand if BI_CAN_EXEC_DYN is also set.
This improves precision of the brand matching, which should eliminate
surprises due to brand ordering.
Revert r315701.
Discussed with and tested by: ed (previous version)
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
CloudABI executables are statically linked and don't have an
interpreter. Setting the interpreter path to NULL used to work
previously, but r314851 introduced code that checks the string
unconditionally. Running CloudABI executables now causes a null pointer
dereference.
Looking at the rest of imgact_elf.c, it seems various other codepaths
already leaned on the fact that the interpreter path is set. Let's just
go ahead and pick an obviously incorrect interpreter path to appease
imgact_elf.c.
MFC after: 1 week
On the original i386, %dr[4-5] were unimplemented but not very clearly
reserved, so debuggers read them to print them. i386 was still doing
this.
On the original athlon64, %dr[4-5] are documented as reserved but are
aliased to %dr[6-7] unless CR4_DE is set, when accessing them traps.
On 2 of my systems, accessing %dr[4-5] trapped sometimes. On my Haswell
system, the apparent randomness was because the boot CPU starts with
CR4_DE set while all other CPUs start with CR4_DE clear. FreeBSD
doesn't support the data breakpoints enabled by CR4_DE and it never
changes this flag, so the flag remains different across CPUs and
the behaviour seemed inconsistent except while booting when the CPU
doesn't change.
The invalid accesses broke:
- read access for printing the registers in ddb "show watches" on CPUs
with CR4_DE set
- read accesses in fill_dbregs() on CPUs with CR4_DE set. This didn't
implement panic(3) since the user case always skipped %dr[4-5].
- write accesses in set_dbregs(). This also didn't affect userland.
When it didn't trap, the aliasing made it fragile.
Don't print the dummy (zero) values of %dr[4-5] in "show watches" for
i386 or amd64. Fix style bugs near this printing.
amd64 also has space in the dbregs struct for the reserved %dr[8-15]
and already didn't print the dummy values for these, and never accessed
any of the 10 reserved debug registers.
Remove cpufuncs for making the invalid accesses. Even amd64 had these.
Otherwise, recent Linux guests will use these instructions, resulting
in #UD exceptions since bhyve doesn't implement MONITOR/MWAIT exits.
This fixes boot-time hangs in recent Linux guests on Ryzen CPUs
(and probably Bulldozer aka AMD FX as well).
Reviewed by: kib
MFC after: 1 week
related struct definitions out into the MI path.
Invert the native ipc structs to the Linux ipc structs convesion logic.
Since 64-bit variant of ipc structs has more precision convert native ipc
structs to the 64-bit Linux ipc structs and then truncate 64-bit values
into the non 64-bit if needed. Unlike Linux, return EOVERFLOW if the
values do not fit.
Fix SYSV IPC for 64-bit Linuxulator which never sets IPC_64 bit.
MFC after: 1 month
the syscalls that are not implemented in Linux kernel itself.
Cleanup DUMMY() macros.
Reviewed by: dchagin, trasz
Approved by: dchagin
MFC after: 1 month
Differential Revision: https://reviews.freebsd.org/D9804
Renumber cluase 4 to 3, per what everybody else did when BSD granted
them permission to remove clause 3. My insistance on keeping the same
numbering for legal reasons is too pedantic, so give up on that point.
Submitted by: Jan Schaumann <jschauma@stevens.edu>
Pull Request: https://github.com/freebsd/freebsd/pull/96
Otherwise kernel traps on NULL dereference if fpu_kern(9) is used from the
thread0 context.
Reported by: cem
Reviewed by: cem, jhb
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
PG_PROMOTED, that indicates whether lingering 4KB page mappings might
need to be flushed on a PDE change that restricts or destroys a 2MB
page mapping. This flag allows the pmap to avoid range invalidations
that are both unnecessary and costly.
Reviewed by: kib, markj
MFC after: 6 weeks
Differential Revision: https://reviews.freebsd.org/D9665
show pte from the pmap of the process of the current DDB thread, instead
of necessarily the PCPU pmap.
Submitted by: Ryan Libby <rlibby@gmail.com>
Reviewed by: kib
MFC after: 1 week
Sponsored by: Dell EMC Isilon
Differential Revision: https://reviews.freebsd.org/D9645
This also adds support for LINUX_ARCH_SET_GS.
Reviewed by: dchagin
MFC after: 2 weeks
Sponsored by: DARPA, AFRL
Differential Revision: https://reviews.freebsd.org/D9372