ordered with the MFENCE instruction. Similar weak guarantees are also
specified by the AMD APM vol. 3 rev. 3.22. x86 pmap methods
pmap_invalidate_cache_range() and pmap_invalidate_cache_pages() braced
CLFLUSH loop with MFENCE both before and after the loop.
In the revision 56 of SDM, Intel stated that all existing
implementations of CLFLUSH are strict, CLFLUSH instructions execution
is ordered WRT other CLFLUSH and writes. Also, the strict behaviour
is made architectural.
A new instruction CLFLUSHOPT (which was documented for some time in
the Instruction Set Extensions Programming Reference) provides the
weak behaviour which was previously attributed to CLFLUSH.
Use CLFLUSHOPT when available. When CLFLUSH is used on Intel CPUs, do
not execute MFENCE before and after the flushing loop.
Reviewed by: alc
Sponsored by: The FreeBSD Foundation
amd64 and i386 platform code contain very similar xen/xen-os.h
The only differences are:
- Functions/variables/types which were unused in i386/xen/xen-os.h:
* xen_xchg
* __xchg_dummy
* __xg
* __xchg
* atomic_t
* atomic_inc
* rdtscll
The functions/variables/types unused in xen-os.h can be dropped and there
is no more differences betwen amd64 and i386.
The new header is placed in x86/include/xen and each platform will have
dummy headers include x86/xen/*.h. This is to be able to include
machine/xen/*.h in the PV drivers.
Submitted by: Julien Grall <julien.grall@citrix.com>
Reviewed by: royger
Differential Revision: https://reviews.freebsd.org/D3880
Sponsored by: Citrix Systems R&D
Due to an off by one the code would read an entry past the table, as
opposed to the last entry which contains the nosys handler.
Reported by: Pawel Biernacki <pawel.biernacki gmail.com>
The current Xen console driver is crashing very quickly when using it on
an ARM guest. This is because the console lock is recursive and it may
lead to recursion on the tty lock and/or corrupt the ring pointer.
Furthermore, the console lock is not always taken where it should be and has
to be released too early because of the way the console has been designed.
Over the years, code has been modified to support various new features but
the driver has not been reworked.
This new driver has been rewritten with the idea of only having a small set
of specific function to write either via the shared ring or the hypercall
interface.
Note that HVM support has been left aside for now because it requires
additional features which are not yet supported. A follow-up patch will be
sent with HVM guest support.
List of items that may be good to have but not mandatory:
- Avoid to flush for each character written when using the tty
- Support multiple consoles
Submitted by: Julien Grall <julien.grall@citrix.com>
Reviewed by: royger
Differential Revision: https://reviews.freebsd.org/D3698
Sponsored by: Citrix Systems R&D
Pull the latest headers for Xen which allow us to add support for ARM and
use new features in FreeBSD.
This is a verbatim copy of the xen/include/public so every headers which
don't exits anymore in the Xen repositories have been dropped.
Note the interface version hasn't been bumped, it will be done in a
follow-up. Although, it requires fix in the code to get it compiled:
- sys/xen/xen_intr.h: evtchn_port_t is already defined in the headers so
drop it.
- {amd64,i386}/include/intr_machdep.h: NR_EVENT_CHANNELS now depends on
xen/interface/event_channel.h, so include it.
- {amd64,i386}/{amd64,i386}/support.S: It's not neccessary to include
machine/intr_machdep.h. This is also fixing build compilation with the
new headers.
- dev/xen/blkfront/blkfront.c: The typedef for blkif_request_segmenthas
been dropped. So directly use struct blkif_request_segment
Finally, modify xen/interface/xen-compat.h to throw a preprocessing error if
__XEN_INTERFACE_VERSION__ is not set. This is allow us to catch any file
where xen/xen-os.h is not correctly included.
Submitted by: Julien Grall <julien.grall@citrix.com>
Reviewed by: royger
Differential Revision: https://reviews.freebsd.org/D3805
Sponsored by: Citrix Systems R&D
belong to a vm object, they can't be paged out. Since they can't be paged
out, they are never enqueued in a paging queue. Nonetheless, passing
PQ_INACTIVE to vm_page_unwire() creates the appearance that these pages
are being enqueued in the inactive queue. As of r288122, we can avoid
this false impression by passing PQ_NONE.
Submitted by: kmacy (an earlier version)
Differential Revision: https://reviews.freebsd.org/D1674
linkers no longer raise an error when undefined weak symbols are
found, but relocate as if the symbol value was 0. Note that we do not
repeat the mistake of userspace dynamic linker of making the symbol
lookup prefer non-weak symbol definition over the weak one, if both
are available. In fact, kernel linker uses the first definition
found, and ignores duplicates.
Signature of the elf_lookup() and elf_obj_lookup() functions changed
to split result/error code and the symbol address returned.
Otherwise, it is impossible to return zero address as the symbol
value, to MD relocation code. This explains the mechanical changes in
elf_machdep.c sources.
The powerpc64 R_PPC_JMP_SLOT handler did not checked error from the
lookup() call, the patch leaves the code as is (untested).
Reported by: glebius
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
running thread.
It is currently implemented only on amd64 and i386; on these
architectures, it is implemented by raising an NMI on the CPU on which
the target thread is currently running. Unlike stack_save_td(), it may
fail, for example if the thread is running in user mode.
This change also modifies the kern.proc.kstack sysctl to use this function,
so that stacks of running threads are shown in the output of "procstat -kk".
This is handy for debugging threads that are stuck in a busy loop.
Reviewed by: bdrewery, jhb, kib
Sponsored by: EMC / Isilon Storage Division
Differential Revision: https://reviews.freebsd.org/D3256
The only operation which is prevented by the hold is the kernel stack
swapout for the faulted thread, which should be fine to allow.
Remove useless checks for NULL curproc or curproc->p_vmspace from the
trap_pfault() wrappers on x86 and powerpc.
Reviewed by: alc (previous version)
Sponsored by: The FreeBSD Foundation
MFC after: 2 weeks
Add a check to preload_search_info to make sure mod is set. Most of the
callers of preload_search_info don't check that the mod parameter is
set, which can cause page faults. While at it, remove some now unnecessary
checks before calling preload_search_info.
Sponsored by: Citrix Systems R&D
Reviewed by: kib
Differential Revision: https://reviews.freebsd.org/D3440
frame buffers and memory mapped UARTs.
1. Delay calling cninit() until after pmap_bootstrap(). This makes
sure we have PMAP initialized enough to add translations. Keep
kdb_init() after cninit() so that we have console when we need
to break into the debugger on boot.
2. Unfortunately, the ATPIC code had be moved as well so as to
avoid a spurious trap #30. The reason for which is not known
at this time.
3. In pmap_mapdev_attr(), when we need to map a device prior to the
VM system being initialized, use virtual_avail as the KVA to map
the device at. In particular, avoid using the direct map on amd64
because we can't demote by virtue of not being able to allocate
yet. Keep track of the translation.
Re-use the translation after the VM has been initialized to not
waste KVA and to satisfy the assumption in uart(4) that the handle
returned for the low-level console is the same as later returned
when the device is probed and attached.
4. In pmap_unmapdev() remove the mapping from the table when called
pre-init. Otherwise keep the mapping. During bus probe and attach
device resources are mapped and unmapped multiple times, which
would have us destroy the mapping used by the low-level console.
5. In pmap_init(), set pmap_initialized to signal that we're not
pre-init anymore. On amd64, bring the direct map in sync with the
translations created at that time.
6. Implement bus_space_map() and bus_space_unmap() for real: when
the tag corresponds to memory space, call the corresponding
pmap_mapdev() and pmap_unmapdev() functions to construct and
actual handle.
7. In efifb.c and vt_vga.c, remove the crutches and hacks and simply
call pmap_mapdev_attr() or bus_space_map() as desired.
Notes:
1. uart(4) already used bus_space_map() during low-level console
setup but since serial ports have traditionally been I/O port
based, the lack of a proper implementation for said function
was not a problem. It has always supported memory mapped UARTs
for low-level consoles by setting hw.uart.console accordingly.
2. The use of the direct map on amd64 without setting caching
attributes has been a bigger problem than previously thought.
This change has the fortunate (and unexpected) side-effect of
fixing various EFI frame buffer problems (though not all).
PR: 191564, 194952
Special thanks to:
1. XipLink, Inc -- generously donated an Intel Bay Trail E3800
based eval board (ADLE3800PC).
2. The FreeBSD Foundation, in particular emaste@ -- for UEFI
support in general and testing.
3. Everyone who tested the proposed for PR 191564.
4. jhb@ and kib@ for being a soundboard and applying a clue bat
if so needed.
data is synchronized by store/load to the variable. The
lapic_write_icr() function ensures that store buffers are flushed
before IPI command is issued.
Discussed with: bde
Tested by: pho
Sponsored by: The FreeBSD Foundation
MFC after: 2 weeks
the SMP structures, synchronized with the load by release store in
release_aps().
The change is formal, x86 strong memory model implicitely provided
the guarantees.
Discussed with: bde
Tested by: pho
Sponsored by: The FreeBSD Foundation
MFC after: 2 weeks
initial thread stack is not adjusted by the tunable, the stack is
allocated too early to get access to the kernel environment. See
TD0_KSTACK_PAGES for the thread0 stack sizing on i386.
The tunable was tested on x86 only. From the visual inspection, it
seems that it might work on arm and powerpc. The arm
USPACE_SVC_STACK_TOP and powerpc USPACE macros seems to be already
incorrect for the threads with non-default kstack size. I only
changed the macros to use variable instead of constant, since I cannot
test.
On arm64, mips and sparc64, some static data structures are sized by
KSTACK_PAGES, so the tunable is disabled.
Sponsored by: The FreeBSD Foundation
MFC after: 2 week
use was removed in r173592 (Nov 2007), yet Xen PV bits continued
referencing the privatespace structure, and were removed in r282274
(Apr 2015).
Discussed with: jhb
Sponsored by: The FreeBSD Foundation
use vtophys() directly instead of vtomach() and retire the no-longer-used
headers <machine/xenfunc.h> and <machine/xenvar.h>.
Reported by: bde (stale bits in <machine/xenfunc.h>)
Reviewed by: royger (earlier version)
Differential Revision: https://reviews.freebsd.org/D3266
vm_offset_t pmap_quick_enter_page(vm_page_t m)
void pmap_quick_remove_page(vm_offset_t kva)
These will create and destroy a temporary, CPU-local KVA mapping of a specified page.
Guarantees:
--Will not sleep and will not fail.
--Safe to call under a non-sleepable lock or from an ithread
Restrictions:
--Not guaranteed to be safe to call from an interrupt filter or under a spin mutex on all platforms
--Current implementation does not guarantee more than one page of mapping space across all platforms. MI code should not make nested calls to pmap_quick_enter_page.
--MI code should not perform locking while holding onto a mapping created by pmap_quick_enter_page
The idea is to use this in busdma, for bounce buffer copies as well as virtually-indexed cache maintenance on mips and arm.
NOTE: the non-i386, non-amd64 implementations of these functions still need review and testing.
Reviewed by: kib
Approved by: kib (mentor)
Differential Revision: http://reviews.freebsd.org/D3013
overflows the stack during root mount in some configurations.
Tested by: Fabian Keil <freebsd-listen@fabiankeil.de> (previous version)
Sponsored by: The FreeBSD Foundation
MFC after: 2 weeks
reported, on APs. We already did this on BSP.
Otherwise, the userspace software which depends on the features
reported by the high CPUID levels is misbehaving. In particular, AVX
detection is non-functional, depending on which CPU thread happens to
execute when doing CPUID. Another victim is the libthr signal
handlers interposer, which needs to save full FPU extended state.
Reported and tested by: Andre Meiser <ortadur@web.de>
Sponsored by: The FreeBSD Foundation
MFC after: 2 weeks
- Fix segment registers to only display the low 16 bits.
- Remove unused handlers and entries for the debug registers.
- Display xcr0 (if valid) in 'show sysregs'.
- Add '0x' prefix to MSR values to match other values in 'show sysregs'.
- MFamd64: Display various MSRs in 'show sysregs'.
- Add a 'show dbregs' to display the value of debug registers.
- Dynamically size the column width for register values to properly
align columns on 64-bit platforms.
- Display %gs for i386 in 'show registers'.
Differential Revision: https://reviews.freebsd.org/D2784
Reviewed by: kib, markj
MFC after: 2 weeks
The i386 and amd64 DDB stack unwinders contain code to detect and handle
the case where the first frame is not completely set up or torn down. This
code was accidentally unused however, since db_backtrace() was never called
with a non-NULL trap frame. This change fixes that.
Also remove get_rsp() from the amd64 code. It appears to have come from
i386, which needs to take into account whether the exception triggered a
CPL switch, since SS:ESP is only pushed onto the stack if so. On amd64,
SS:RSP is pushed regardless, so get_rsp() was doing the wrong thing for
kernel-mode exceptions. As a result, we can also remove custom print
functions for these registers.
Reviewed by: jhb
Sponsored by: EMC / Isilon Storage Division
Differential Revision: https://reviews.freebsd.org/D2881
If we can't find a symbol corresponding to the faulting instruction, assume
that the previously-executed function is a call and attempt to find the
calling function using the return address on the stack. Otherwise we end
up associating the last stack frame with the current call, which is
incorrect and causes the unwinder to skip printing of the calling function,
resulting in a confusing backtrace.
Reviewed by: jhb
Sponsored by: EMC / Isilon Storage Division
Differential Revision: https://reviews.freebsd.org/D2859
in lockstat.ko. This means that lockstat probes now have typed arguments and
will utilize SDT probe hot-patching support when it arrives.
Reviewed by: gnn
Differential Revision: https://reviews.freebsd.org/D2993
belongs to the kernel stack address range for the thread. Right now,
code checks that new frame is not farther then KSTACK_PAGES pages from
the current frame, which allows the address to point past the top of
the stack.
Reviewed by: andrew, emaste, markj
Differential revision: https://reviews.freebsd.org/D3108
Sponsored by: The FreeBSD Foundation
MFC after: 2 weeks
If KSTACK_PAGES was changed to anything alse than the default,
the value from param.h was taken instead in some places and
the value from KENRCONF in some others. This resulted in
inconsistency which caused corruption in SMP envorinment.
Ensure all places where KSTACK_PAGES are used the opt_kstack_pages.h
is included.
The file opt_kstack_pages.h could not be included in param.h
because was breaking the toolchain compilation.
Reviewed by: kib
Obtained from: Semihalf
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D3094
versions of the x87 tags. The conversion is naive, used abridged tag
is converted to valid unabridged, without additional checks for zero
and special values.
Noted by: bde
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
i386/include/frame.h after a code was moved from machdep.c to frame.h
in r284925.
Use include guards style similar to other guards.
Noted by: bde
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
provide a semantic defined by the C11 fences with corresponding
memory_order.
atomic_thread_fence_acq() gives r | r, w, where r and w are read and
write accesses, and | denotes the fence itself.
atomic_thread_fence_rel() is r, w | w.
atomic_thread_fence_acq_rel() is the combination of the acquire and
release in single operation. Note that reads after the acq+rel fence
could be made visible before writes preceeding the fence.
atomic_thread_fence_seq_cst() orders all accesses before/after the
fence, and the fence itself is globally ordered against other
sequentially consistent atomic operations.
Reviewed by: alc
Discussed with: bde
Sponsored by: The FreeBSD Foundation
MFC after: 3 weeks
macros on amd64 and i386. Move the definition to machine/param.h.
kgdb defines INKERNEL() too, the conflict is resolved by renaming kgdb
version to PINKERNEL().
On i386, correct the lowest kernel address. After the shared page was
introduced, USRSTACK no longer points to the last user address + 1 [*]
Submitted by: Oliver Pinter [*]
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
restore the FPU state from the format of machine FSAVE area. The
intended use is for ABI emulators to provide FSAVE-formatted FPU state
to usermode requiring it, while kernel could use FXSAVE due to
XMM/XSAVE.
The core functionality to convert from/to FXSAVE format is shared with
the fill_fpregs_xmm() and set_fpregs_xmm(). Move the later functions
to npx.c and rename them to npx_fill_fpregs_xmm() and
npx_set_fpregs_xmm(). They differ from nptx_get/set_fsave(9) since
our mcontext contains padding to be zeroed or ignored.
fill_fpregs() and set_fpregs() could be converted to use the new
interface, but there are small differences to handle.
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
obtain the thread %fs and %gs bases. Add x86 PT_SETFSBASE and
PT_SETGSBASE requests to set the bases from debuggers. The set
requests, similarly to the sysarch({I386,AMD64}_SET_FSBASE),
override the corresponding segment registers.
The main purpose of the operations is to retrieve and modify the tcb
address for debuggee.
Sponsored by: The FreeBSD Foundation
MFC after: 2 weeks
atomic_load_acq(9), on it source, for x86.
Right now, atomic_load_acq() on x86 is sequentially consistent with
other atomics, code ensures this by doing store/load barrier by
performing locked nop on the source. Provide separate primitive
__storeload_barrier(), which is implemented as the locked nop done on
a cpu-private variable, and put __storeload_barrier() before load, to
keep seq_cst semantic but avoid introducing false dependency on the
no-modification of the source for its later use.
Note that seq_cst property of x86 atomic_load_acq() is not documented
and not carried by atomics implementations on other architectures,
although some kernel code relies on the behaviour. This commit does
not intend to change this.
Reviewed by: alc
Discussed with: bde
Tested by: pho
Sponsored by: The FreeBSD Foundation
MFC after: 2 weeks
While here, also report %eflags from the i386 trapframe.
Differential Revision: https://reviews.freebsd.org/D2743
Reviewed by: kib
Obtained from: 1 month
trapframes are cleared by explicitly pushing a zero and then moving
the segment register into the low 16 bits. Certain Intel processors
treat a push of a segment register as a move of the segment register
into the low 16 bits leaving the upper 16 bits of the word in the
stack unchanged.
Reviewed by: kib
MFC after: 1 month
This will require for AArch64 as we dont have modules yet.
Sponsored by: HEIF5
Sponsored by: ARM Ltd.
Differential Revision: https://reviews.freebsd.org/D1997
Use the same scheme implemented to manage credentials.
Code needing to look at process's credentials (as opposed to thred's) is
provided with *_proc variants of relevant functions.
Places which possibly had to take the proc lock anyway still use the proc
pointer to access limits.
Thread credentials are maintained as follows: each thread has a pointer to
creds and a reference on them. The pointer is compared with proc's creds on
userspace<->kernel boundary and updated if needed.
This patch introduces a counter which can be compared instead, so that more
structures can use this scheme without adding more comparisons on the boundary.
Remove unneeded NULL checks in trap_fatal().
Since td_name is an array member of struct thread, it can never be NULL,
so the check can be removed. In addition, curproc can never be NULL,
so remove the if statement, and splice the two printfs() together.
While here, remove the u_long cast, and use the correct printf format
specifier for curproc->p_pid.
Requested by: jhb
MFC after: 3 days
rev. 55. The modern CPUs cache and TLB descriptions looked quite
questionable without the update, e.g. Haswell i7 4770S reported:
Data TLB: 4 KB pages, 4-way set associative, 64 entries
L2 cache: 256 kbytes, 8-way associative, 64 bytes/line
After the update, the report is:
Data TLB: 1 GByte pages, 4-way set associative, 4 entries
Data TLB: 4 KB pages, 4-way set associative, 64 entries
Instruction TLB: 2M/4M pages, fully associative, 8 entries
Instruction TLB: 4KByte pages, 8-way set associative, 64 entries
64-Byte prefetching
Shared 2nd-Level TLB: 4 KByte/2MByte pages, 8-way associative, 1024 entries
L2 cache: 256 kbytes, 8-way associative, 64 bytes/line
Some tags were apparently removed from the table 3-21, Vol. 2A. Keep
them around, but add a comment stating the removal.
Update the format line for cpu_stdext_feature according to the bits
from the SDM rev.55. It appears that Haswells do not store %cs and
%ds values in the FPU save area.
Store content of the %ecx register from the CPUID leaf 0x7
subleaf 0 as cpu_stdext_feature2 and print defined bits from it,
again acording to SDM rev. 55.
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Native ABI do not need signal conversion, only emulators may want this. Usually
emulators implements its own sv_sendsig method. For now only ibcs2 emulator does
not have own sv_sendsig implementation and depends on native sendsig() method.
So, remove any extra attempts to convert signal numbers from native sendsig()
methods except from i386 where ibsc2 is living.
1. Linux sigset always 64 bit on all platforms. In order to move Linux
sigset code to the linux_common module define it as 64 bit int. Move
Linux sigset manipulation routines to the MI path.
2. Move Linux signal number definitions to the MI path. In general, they
are the same on all platforms except for a few signals.
3. Map Linux RT signals to the FreeBSD RT signals and hide signal conversion
tables to avoid conversion errors.
4. Emulate Linux SIGPWR signal via FreeBSD SIGRTMIN signal which is outside
of allowed on Linux signal numbers.
PR: 197216
argument is not a null pointer, and the ss_flags member pointed to by ss
contains flags other than SS_DISABLE. However, in fact, Linux also
allows SS_ONSTACK flag which is simply ignored.
For buggy apps (at least mono) ignore other than SS_DISABLE
flags as a Linux do.
While here move MI part of sigaltstack code to the appropriate place.
Reported by: abi at abinet dot ru
around kqueue() to implement epoll subset of functionality.
The kqueue user data are 32bit on i386 which is not enough for
epoll user data, so we keep user data in the proc emuldata.
Initial patch developed by rdivacky@ in 2007, then extended
by Yuri Victorovich @ r255672 and finished by me
in collaboration with mjg@ and jillies@.
Differential Revision: https://reviews.freebsd.org/D1092
to determine the kernel version (this saves one uname call).
Temporarily disable the export of a note.Linux section until I figured
out how to change the kernel version in the note.Linux on the fly.
Differential Revision: https://reviews.freebsd.org/D1081
Reviewed by: trasz
The AT_EACCESS and AT_SYMLINK_NOFOLLOW flags are actually implemented
within the glibc wrapper function for faccessat(). If either of these
flags are specified, then the wrapper function employs fstatat() to
determine access permissions.
Differential Revision: https://reviews.freebsd.org/D1078
Reviewed by: trasz
following primary purposes:
1. Remove the dependency of linsysfs and linprocfs modules from linux.ko,
which will be architecture specific on amd64.
2. Incorporate into linux_common.ko general code for platforms on which
we'll support two Linuxulator modules (for both instruction set - 32 & 64 bit).
3. Move malloc(9) declaration to linux_common.ko, to enable getting memory
usage statistics properly.
Currently linux_common.ko incorporates a code from linux_mib.c and linux_util.c
and linprocfs, linsysfs and linux kernel modules depend on linux_common.ko.
Temporarily remove dtrace garbage from linux_mib.c and linux_util.c
Differential Revision: https://reviews.freebsd.org/D1072
In collaboration with: Vassilis Laganakos.
Reviewed by: trasz
Move struct ipc_perm definition to the MD path as it differs for 64 and
32 bit platform.
Differential Revision: https://reviews.freebsd.org/D1068
Reviewed by: trasz
