Commit Graph

229334 Commits

Author SHA1 Message Date
Warner Losh
36a910fba3 Make igor happier with this file:
o Don't use contractions.
o Add common after e.g. where needed
2018-01-18 22:20:30 +00:00
John Baldwin
f36b1fe0bd Remove two no-longer-used labels from the NMI interrupt handler.
Reviewed by:	kib
2018-01-18 22:13:53 +00:00
Conrad Meyer
844d9543dc Add ccp(4): experimental driver for AMD Crypto Co-Processor
* Registers TRNG source for random(4)
* Finds available queues, LSBs; allocates static objects
* Allocates a shared MSI-X for all queues.  The hardware does not have
  separate interrupts per queue.  Working interrupt mode driver.
* Computes SHA hashes, HMAC.  Passes cryptotest.py, cryptocheck tests.
* Does AES-CBC, CTR mode, and XTS.  cryptotest.py and cryptocheck pass.
* Support for "authenc" (AES + HMAC).  (SHA1 seems to result in
  "unaligned" cleartext inputs from cryptocheck -- which the engine
  cannot handle.  SHA2 seems to work fine.)
* GCM passes for block-multiple AAD, input lengths

Largely based on ccr(4), part of cxgbe(4).

Rough performance averages on AMD Ryzen 1950X (4kB buffer):
aesni:      SHA1: ~8300 Mb/s    SHA256: ~8000 Mb/s
ccp:               ~630 Mb/s    SHA256:  ~660 Mb/s  SHA512:  ~700 Mb/s
cryptosoft:       ~1800 Mb/s    SHA256: ~1800 Mb/s  SHA512: ~2700 Mb/s

As you can see, performance is poor in comparison to aesni(4) and even
cryptosoft (due to high setup cost).  At a larger buffer size (128kB),
throughput is a little better (but still worse than aesni(4)):

aesni:      SHA1:~10400 Mb/s    SHA256: ~9950 Mb/s
ccp:              ~2200 Mb/s    SHA256: ~2600 Mb/s  SHA512: ~3800 Mb/s
cryptosoft:       ~1750 Mb/s    SHA256: ~1800 Mb/s  SHA512: ~2700 Mb/s

AES performance has a similar story:

aesni:      4kB: ~11250 Mb/s    128kB: ~11250 Mb/s
ccp:               ~350 Mb/s    128kB:  ~4600 Mb/s
cryptosoft:       ~1750 Mb/s    128kB:  ~1700 Mb/s

This driver is EXPERIMENTAL.  You should verify cryptographic results on
typical and corner case inputs from your application against a known- good
implementation.

Sponsored by:	Dell EMC Isilon
Differential Revision:	https://reviews.freebsd.org/D12723
2018-01-18 22:01:30 +00:00
Dimitry Andric
024469e429 Pull in r322106 from upstream llvm trunk (by Alexey Bataev):
[COST]Fix PR35865: Fix cost model evaluation for shuffle on X86.

  Summary:
  If the vector type is transformed to non-vector single type, the
  compile may crash trying to get vector information about non-vector
  type.

  Reviewers: RKSimon, spatel, mkuper, hfinkel

  Subscribers: llvm-commits

  Differential Revision: https://reviews.llvm.org/D41862

This should fix "Not a vector MVT!" errors when building the
games/dhewm3 port.

Reported by:	jbeich
PR:		225271
2018-01-18 21:46:09 +00:00
Dimitry Andric
6bee06efd1 Pull in r322016 from upstream llvm trunk (by Sanjay Patel):
[ValueTracking] remove overzealous assert

  The test is derived from a failing fuzz test:
  https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=5008

  Credit to @rksimon for pointing out the problem.

This should fix "Bad flavor while matching min/max" errors when building
the graphics/libsixel and science/kst2 ports.

Reported by:	jbeich
PR:		225268, 225269
2018-01-18 21:44:07 +00:00
Ed Maste
62de8f4add lld: Fix incorrect physical address on self-referencing AT command.
When a section placement (AT) command references the section itself,
the physical address of the section in the ELF header was calculated
incorrectly due to alignment happening right after the location
pointer's value was captured.

The problem was diagnosed and the first version of the patch written
by Erick Reyes.

Obtained from:	LLVM r322421 by Rafael Espindola
2018-01-18 21:39:59 +00:00
Ed Maste
cc877d7c33 lld: Handle parsing AT(ADDR(.foo-bar)).
The problem we had with it is that anything inside an AT is an
expression, so we failed to parse the section name because of the - in
it.

Requested by:	royger
Obtained from:	LLVM r322801 by Rafael Espindola
2018-01-18 21:39:19 +00:00
Ed Maste
d3f08be7dc lld: Fix for ld.lld does not accept "AT" syntax for declaring LMA region
AT> lma_region expression allows to specify the memory region
for section load address.

Should fix [upstream LLVM] PR35684.

LLVM review: https://reviews.llvm.org/D41397

Obtained from:	LLVM r322359 by George Rimar
2018-01-18 21:38:21 +00:00
Conrad Meyer
f5b26e1334 Add Elf_Nhdr definition to match NetBSD, OpenBSD, Linux
The mesa port started to use this type and fails to build without it.

NetBSD: http://cvsweb.netbsd.org/bsdweb.cgi/src/sys/sys/exec_elf.h.diff?r1=1.26&r2=1.27&f=h
OpenBSD: http://cvsweb.openbsd.org/cgi-bin/cvsweb/src/sys/sys/exec_elf.h.diff?r1=1.21&r2=1.22&f=h

PR:		225302
Reported by:	Greg V <greg AT unrelenting.technology>
Sponsored by:	Dell EMC Isilon
2018-01-18 21:19:57 +00:00
Brad Davis
5b0065e7db Teach the resolv startup script to respect its enable flag.
Reviewed by:	will, imp
Approved by:	imp
2018-01-18 20:45:41 +00:00
John Baldwin
7f513d17b2 Adjust branch target in NMI handler for the !PTI case.
In the !PTI case the NMI handler jumped past the instructions that set
%rdi to point to the current PCB, but the target instructions assumed %rdi
were set.

Reviewed by:	kib
Tested by:	pho
2018-01-18 20:12:12 +00:00
John Baldwin
9a7a98a0dc Update various statements in vmstat(8) to match reality.
- The process stats are actually thread counts rather than process
  counts.
- Simplify various descriptions to remove mention of stats that are
  updated every 5 seconds (all VM related stats are now "instant",
  only the load average is updated every 5 seconds).
- Don't make any mention of special treatment for processes that have
  been active in the last 20 seconds.  We don't track that stat.
- Rework the description of active virtual memory.  Call it mapped
  virtual memory and explicitly point out it is not the same as the
  active page queue (which corresponds to "Active" in top(1)), and
  also hint at the possible bogusness of the value (e.g. if a process
  maps a single page out of a multiple GB file, the entire file's size
  is considered mapped).
- Simplify a few descriptions that implied their output was a value
  per interval.  All of the "rate" values are per-second rates scaled
  across the interval.
- Update a few comments for 'struct vmtotal' along similar lines.

Reported by:	mwlucas (indirectly)
Reviewed by:	kib
MFC after:	1 week
Differential Revision:	https://reviews.freebsd.org/D13905
2018-01-18 19:43:02 +00:00
Ruslan Bukin
e6dd0a0e92 UART Clock Selection Register holds a divider value for a supplied clock,
not a final baud rate. The value for this register has to be calculated.

Sponsored by:	DARPA, AFRL
2018-01-18 18:19:31 +00:00
Ruslan Bukin
9f7743f2c8 Support for UART device found in Qualcomm Snapdragon 410E SoC.
Tested on DragonBoard 410c.

Reviewed by:	andrew
Sponsored by:	DARPA, AFRL
Differential Revision:	https://reviews.freebsd.org/D13972
2018-01-18 17:43:32 +00:00
Ruslan Bukin
9d00c86401 Set the base address of translation table 0.
This fixes operation on Qualcomm Snapdragon and some other platforms.

During boot time on subsystems initialization we have some amount of
kernel threads created, then scheduler gives CPU time to each thread.
Eventually scheduler returns CPU execution back to thread 0. In this
case writing zero to ttbr0 in cpu_switch leads Qualcomm board to
reboot (asynchronously, CPU continues execution).

Similar to other kernel threads install a valid physical address
(kernel pmap) to user page table base register ttbr0.

Reviewed by:	andrew
Sponsored by:	DARPA, AFRL
Differential Revision:	https://reviews.freebsd.org/D13536
2018-01-18 16:20:09 +00:00
Emmanuel Vadot
becffb36cc nfs: Do not printf each time a lock structure is freed during module unload
There can be a lot of those structures and printing a line each time we free
one on module unload.

MFC after:	3 days
2018-01-18 15:28:49 +00:00
Konstantin Belousov
3705dda7e4 Move the kernphys declaration to machine/md_var.h.
Apparently machinde/cpu.h is supposed to contain MD implementations of
MI interfaces.  Also, remove kernphys declaration from machdep.c,
since it is already provided by md_var.h.

Requested and reviewed by:	bde
MFC after:	13 days
2018-01-18 15:15:35 +00:00
Andriy Gapon
3e4f610dad correct read-ahead calculations in vfs_bio_getpages
Previously the calculations were done as if the requested region
ended at the start of the last requested page, not its end.
The problem as actually quite minor as it affected only stats and
page prefaulting, not the actual page data, and only with specific
parameters.

Reviewed by:	kib (previous version)
MFC after:	2 weeks
2018-01-18 12:59:04 +00:00
Konstantin Belousov
ac97ccbab5 Fix compilation with gcc.
etext is already declared in machine/cpu.h, move kernphys declaration
there too.

Based on the patch by:	bde
MFC after:	13 days
2018-01-18 11:21:03 +00:00
Konstantin Belousov
406bc0da95 Fix compilation with gas.
Submitted by:	bde
MFC after:	13 days
2018-01-18 11:19:58 +00:00
Konstantin Belousov
0d6c61ec30 Remove the 'last' argument from the pmap_pti_free_page().
It is in fact unused.

Noted and reviewed by:	markj
Sponsored by:	The FreeBSD Foundation
MFC after:	13 days
2018-01-18 11:01:41 +00:00
Andrew Turner
7680515c07 Add a pmap invalidate that doesn't call sched_pin.
When demoting DMAP pages curthread may be pointing to data within the
page we are demoting. Create a new invalidate that doesn't pin and use
it in the demote case.

As the demote has both interrupts disabled, and is within a critical section
this is safe from having the scheduler from switching to another CPU.

Reported by:	loos
Reviewed by:	loos
Sponsored by:	DARPA, AFRL
Differential Revision:	https://reviews.freebsd.org/D13955
2018-01-18 10:52:31 +00:00
Wojciech Macek
720212d30d Call platform_smp_ap_init before decr_ap_init
In platform_smp_ap_init we are doing some crucial code (eg. set LPCR register)
    which have influence over further execution.

    Practiculary in PowerNV platform we have experienced Data Storage Interrupt
    before we set apropriate LPCR. It caused code execution from location which was
    legal in bootloader (petitboot based on linux) but illegal in FreeBSD
2018-01-18 08:34:20 +00:00
Wojciech Macek
054a090d49 PPC64: fix TOC behavior on process initialization
Set stack pointer to correct value after thread's stack pointer restore

Restoring new thread's stack pointer caused stack corruption because
restored stack pointer didn't point to callee (cpu_switch) stack frame but
caller stack frame.

As a result we had mysterious errors in caller function (sched_switch).

Solution: simply set stack pointer to correct value

Also, initialize TOC to a valid pointer once the thread is being
created.

Created by:            Patryk Duda <pdk@semihalf.com>
Submitted by:          Wojciech Macek <wma@semihalf.com>
Obtained from:         Semihalf
Reviewed by:           nwhitehorn
Differential revision: https://reviews.freebsd.org/D13947
Sponsored by:          QCM Technologies
2018-01-18 07:42:51 +00:00
Wojciech Macek
8a0112ca65 PPC: machdep, zero BSS always but BookE
Zero BSS always. The only case when this operation is
ommitted is when booting on BookE.

Created by:            Wojciech Macek <wma@semihalf.com>
Obtained from:         Semihalf
Reviewed by:           imp, nwhitehorn
Differential revision: https://reviews.freebsd.org/D13948
Sponsored by:          QCM Technologies
2018-01-18 07:41:04 +00:00
Wojciech Macek
5b3e8b0725 KDB: restart only CPUs stopped by KDB
There is a case when not all CPUs went online. In that situation,
restart only APs which were operational before entering KDB.

Created by:            Wojciech Macek <wma@semihalf.com>
Obtained from:         Semihalf
Reviewed by:           nwhitehorn
Differential revision: https://reviews.freebsd.org/D13949
Sponsored by:          QCM Technologies
2018-01-18 07:38:54 +00:00
Wojciech Macek
e70f868f17 PPC64: add AHCI back to GENERIC64 2018-01-18 06:28:21 +00:00
Alan Somers
6f7f85e0e1 gnop(8): add the ability to set a nop provider's physical path
While I'm here, expand the existing tests a bit.

MFC after:	3 weeks
Differential Revision:	https://reviews.freebsd.org/D13579
2018-01-18 05:57:10 +00:00
Kyle Evans
db180ae55c stand: Add /boot/overlays to allow separation of overlays from base FDT
This matches directory structure used commonly in Linux-land, and it's
cleaner than mixing overlays into the existing module paths. Overlays are
still mixed in by specifying fdt_overlays in loader.conf(5).

Reviewed by:	manu
Differential Revision:	https://reviews.freebsd.org/D13922
2018-01-18 04:58:54 +00:00
Kyle Evans
6780e684d4 libfdt: Update to 1.4.6, switch to using libfdt for overlay support
libfdt highlights since 1.4.3:

- fdt_property_placeholder added to create a property without specifying its
value at creation time
- stringlist helper functions added to libfdt
- Improved overlay support
- Various internal cleanup

Also switch stand/fdt over to using libfdt for overlay support with this
update. Our current overlay implementation works only for limited use cases
with overlays generated only by some specific versions of our dtc(1). Swap
it out for the libfdt implementation, which supports any properly generated
overlay being applied to a properly generated base.

This will be followed up fairly soon with an update to dtc(1) in tree to
properly generate overlays.

MFC note: the <stdlib.h> include this update introduces in libfdt_env.h is
apparently not necessary in the context we use this in. It's not immediately
clear to me the motivation for it being introduced, but it came in with
overlay support. I've left it in for the sake of accuracy and because it's
not harmful here on HEAD, but MFC'ing this to stable/11 will require
wrapping the #include in an `#ifndef _STANDALONE` block or else it will
cause build failures.

Tested on:	Banana Pi-M3 (ARMv7)
Tested on:	Pine64 (aarch64)
Tested on:	PowerPC [nwhitehorn]
Reviewed by:	manu, nwhitehorn
MFC after:	1 week
Differential Revision:	https://reviews.freebsd.org/D13893
2018-01-18 04:39:09 +00:00
John Baldwin
66f8917bea Adjust format string to fix build. 2018-01-18 00:24:05 +00:00
John Baldwin
449af04fc9 Tidy some whitespace. 2018-01-18 00:23:11 +00:00
John Baldwin
65eefbe422 Save and restore guest debug registers.
Currently most of the debug registers are not saved and restored
during VM transitions allowing guest and host debug register values to
leak into the opposite context.  One result is that hardware
watchpoints do not work reliably within a guest under VT-x.

Due to differences in SVM and VT-x, slightly different approaches are
used.

For VT-x:

- Enable debug register save/restore for VM entry/exit in the VMCS for
  DR7 and MSR_DEBUGCTL.
- Explicitly save DR0-3,6 of the guest.
- Explicitly save DR0-3,6-7, MSR_DEBUGCTL, and the trap flag from
  %rflags for the host.  Note that because DR6 is "software" managed
  and not stored in the VMCS a kernel debugger which single steps
  through VM entry could corrupt the guest DR6 (since a single step
  trap taken after loading the guest DR6 could alter the DR6
  register).  To avoid this, explicitly disable single-stepping via
  the trace flag before loading the guest DR6.  A determined debugger
  could still defeat this by setting a breakpoint after the guest DR6
  was loaded and then single-stepping.

For SVM:
- Enable debug register caching in the VMCB for DR6/DR7.
- Explicitly save DR0-3 of the guest.
- Explicitly save DR0-3,6-7, and MSR_DEBUGCTL for the host.  Since SVM
  saves the guest DR6 in the VMCB, the race with single-stepping
  described for VT-x does not exist.

For both platforms, expose all of the guest DRx values via --get-drX
and --set-drX flags to bhyvectl.

Discussed with:	avg, grehan
Tested by:	avg (SVM), myself (VT-x)
MFC after:	1 month
Differential Revision:	https://reviews.freebsd.org/D13229
2018-01-17 23:11:25 +00:00
John Baldwin
58c4aee0d7 Require the SHF_ALLOC flag for program sections from kernel object modules.
ELF object files can contain program sections which are not supposed
to be loaded into memory (e.g. .comment).  Normally the static linker
uses these flags to decide which sections are allocated to loadable
program segments in ELF binaries and shared objects (including kernels
on all architectures and kernel modules on architectures other than
amd64).

Mapping ELF object files (such as amd64 kernel modules) into memory
directly is a bit of a grey area.  ELF object files are intended to be
used as inputs to the static linker.  As a result, there is not a
standardized definition for what the memory layout of an ELF object
should be (none of the section headers have valid virtual memory
addresses for example).

The kernel and loader were not checking the SHF_ALLOC flag but loading
any program sections with certain types such as SHT_PROGBITS.  As a
result, the kernel and loader would load into RAM some sections that
weren't marked with SHF_ALLOC such as .comment that are not loaded
into RAM for kernel modules on other architectures (which are
implemented as ELF shared objects).  Aside from possibly requiring
slightly more RAM to hold a kernel module this does not affect runtime
correctness as the kernel relocates symbols based on the layout it
uses.

Debuggers such as gdb and lldb do not extract symbol tables from a
running process or kernel.  Instead, they replicate the memory layout
of ELF executables and shared objects and use that to construct their
own symbol tables.  For executables and shared objects this works
fine.  For ELF objects the current logic in kgdb (and probably lldb
based on a simple reading) assumes that only sections with SHF_ALLOC
are memory resident when constructing a memory layout.  If the
debugger constructs a different memory layout than the kernel, then it
will compute different addresses for symbols causing symbols in the
debugger to appear to have the wrong values (though the kernel itself
is working fine).  The current port of mdb does not check SHF_ALLOC as
it replicates the kernel's logic in its existing kernel support.

The bfd linker sorts the sections in ELF object files such that all of
the allocated sections (sections with SHF_ALLOCATED) are placed first
followed by unallocated sections.  As a result, when kgdb composed a
memory layout using only the allocated sections, this layout happened
to match the layout used by the kernel and loader.  The lld linker
does not sort the sections in ELF object files and mixed allocated and
unallocated sections.  This resulted in kgdb composing a different
memory layout than the kernel and loader.

We could either patch kgdb (and possibly in the future lldb) to use
custom handling when generating memory layouts for kernel modules that
are ELF objects, or we could change the kernel and loader to check
SHF_ALLOCATED.  I chose the latter as I feel we shouldn't be loading
things into RAM that the module won't use.  This should mostly be a
NOP when linking with bfd but will allow the existing kgdb to work
with amd64 kernel modules linked with lld.

Note that we only require SHF_ALLOC for "program" sections for types
like SHT_PROGBITS and SHT_NOBITS.  Other section types such as symbol
tables, string tables, and relocations must also be loaded and are not
marked with SHF_ALLOC.

Reported by:	np
Reviewed by:	kib, emaste
MFC after:	1 month
Sponsored by:	Chelsio Communications
Differential Revision:	https://reviews.freebsd.org/D13926
2018-01-17 22:51:59 +00:00
Conrad Meyer
0fdf7fa846 Convert ls(1) to not use libxo(3)
libxo imposes a large burden on system utilities. In the case of ls, that
burden is difficult to justify -- any language that can interact with json
output can use readdir(3) and stat(2).

Logically, this reverts r291607, r285857, r285803, r285734, r285425,
r284494, r284489, r284252, and r284198.

Kyua tests continue to pass (libxo integration was entirely untested).

Reported by:	many
Reviewed by:	imp
Discussed with:	manu, bdrewery
Sponsored by:	Dell EMC Isilon
Differential Revision:	https://reviews.freebsd.org/D13959
2018-01-17 22:47:34 +00:00
John Baldwin
b1288166e0 Use long for the last argument to VOP_PATHCONF rather than a register_t.
pathconf(2) and fpathconf(2) both return a long.  The kern_[f]pathconf()
functions now accept a pointer to a long value rather than modifying
td_retval directly.  Instead, the system calls explicitly store the
returned long value in td_retval[0].

Requested by:	bde
Reviewed by:	kib
Sponsored by:	Chelsio Communications
2018-01-17 22:36:58 +00:00
Landon J. Fuller
19a63eb534 bwn(4): Enable, by default, the opt-in support for bhnd(4) introduced in
r326454.

bwn(4)/bhnd(4) has been tested with most chipsets currently supported by
bwn(4), and this change should be transparent to existing bwn(4) users;
please report any regressions that you do encounter.

To revert to using siba_bwn(4) instead of bhnd(4), place the following
lines in loader.conf(5):

  hw.bwn_pci.preferred="0"

Once we're satisfied that the switch to bhnd(4) has seen sufficient broader
testing, bwn(4) will be migrated to use the native bhnd(9) interface
directly, and support for siba_bwn(4) will be dropped (see D13518).

Sponsored by:	The FreeBSD Foundation
2018-01-17 22:33:19 +00:00
Mark Johnston
9cb26f73ea Annotate a couple of changes from r328083.
Reviewed by:	kib
X-MFC with:	r328083
2018-01-17 21:52:12 +00:00
Ed Maste
559d4a5216 kldxref: additional sytle(9) cleanup
Reported by:	kib (via comments in D13957)
Sponsored by:	The FreeBSD Foundation
2018-01-17 20:43:30 +00:00
Ed Maste
e2d0802c6b kldxref: improve style(9)
Address style issues including some previously raised in D13923.

- Use designated initializers for structs
- Always use bracketed return style
- No initialization in declarations
- Align function prototype names
- Remove old commented code/unused includes

Submitted by:	Mitchell Horne <mhorne063@gmail.com>
Reviewed by:	kib
Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D13943
2018-01-17 19:59:43 +00:00
Pedro F. Giffuni
90b618f35b ufs: use mallocarray(9).
Basic use of mallocarray to prevent overflows: static analyzers are also
likely to perform additional checks.

Since mallocarray expects unsigned parameters, unsign some
related variables to minimize sign conversions.

Reviewed by:	mckusick
2018-01-17 18:18:33 +00:00
Kirk McKusick
72f854ce8f Correct fsck journal-recovery code to update a cylinder-group
check-hash after making changes to the cylinder group. The problem
was that the journal-recovery code was calling the libufs bwrite()
function instead of the cgput() function. The cgput() function updates
the cylinder-group check-hash before writing the cylinder group.

This change required the additions of the cgget() and cgput() functions
to the libufs API to avoid a gratuitous bcopy of every cylinder group
to be read or written. These new functions have been added to the
libufs manual pages. This was the first opportunity that I have had
to use and document the use of the EDOOFUS error code.

Reviewed by: kib
Reported by: emaste and others
2018-01-17 17:58:24 +00:00
Dimitry Andric
64e12b4140 Revert r327340, as the workaround for rep prefixes followed by .byte
directives is no longer needed after r328090.
2018-01-17 17:14:19 +00:00
Dimitry Andric
d23c4359df Pull in r322623 from upstream llvm trunk (by Andrew V. Tischenko):
Allow usage of X86-prefixes as separate instrs.
  Differential Revision: https://reviews.llvm.org/D42102

This should fix parse errors when x86 prefixes (such as 'lock' and
'rep') are followed by various non-mnemonic tokens, e.g. comments, .byte
directives and labels.

PR:		224669,225054
2018-01-17 17:11:55 +00:00
Warner Losh
7e5f6f2588 Move setting of CAM_SIM_QUEUED to before we actually submit it to the
hardware. Setting it after is racy, and we can lose the race on a
heavily loaded system.

Reviewed by: scottl@, gallatin@
Sponsored by: Netflix
2018-01-17 17:08:26 +00:00
Fabien Thomas
cb43ed2815 Only call flush in pipe mode.
It fixes a crash with a socket in top mode.

Ex:
# pmcstat -R 127.0.0.1:8080 -T -w1
then
# pmcstat -n1 -Sclock.prof -Slock.failed -O 127.0.0.1:8080

MFC after:	1 week
Sponsored by:	Stormshield
2018-01-17 16:55:35 +00:00
Fabien Thomas
9f4f1d4d1f Fix pmcstat exit from kernel introduced by r325275.
pmcstat request for close will generate a close event.
This event will be in turn received by pmcstat to close the file.

Reviewed by:	kib
Tested by:	pho
MFC after:	1 week
Sponsored by: Stormshield
2018-01-17 16:41:22 +00:00
Baptiste Daroussin
27522b2c36 Update pciids to 2018.01.14
MFC after:	3 days
2018-01-17 13:25:41 +00:00
Dimitry Andric
2d3c3a5038 Fix buildworld after r328075, by also renaming cgget to cglookup in
fsdb.

Reported by:	ohartmann@walstatt.org,david@catwhisker.org
Pointy hat to:	mckusick
2018-01-17 13:19:37 +00:00
Konstantin Belousov
bd50262f70 PTI for amd64.
The implementation of the Kernel Page Table Isolation (KPTI) for
amd64, first version. It provides a workaround for the 'meltdown'
vulnerability.  PTI is turned off by default for now, enable with the
loader tunable vm.pmap.pti=1.

The pmap page table is split into kernel-mode table and user-mode
table. Kernel-mode table is identical to the non-PTI table, while
usermode table is obtained from kernel table by leaving userspace
mappings intact, but only leaving the following parts of the kernel
mapped:

    kernel text (but not modules text)
    PCPU
    GDT/IDT/user LDT/task structures
    IST stacks for NMI and doublefault handlers.

Kernel switches to user page table before returning to usermode, and
restores full kernel page table on the entry. Initial kernel-mode
stack for PTI trampoline is allocated in PCPU, it is only 16
qwords.  Kernel entry trampoline switches page tables. then the
hardware trap frame is copied to the normal kstack, and execution
continues.

IST stacks are kept mapped and no trampoline is needed for
NMI/doublefault, but of course page table switch is performed.

On return to usermode, the trampoline is used again, iret frame is
copied to the trampoline stack, page tables are switched and iretq is
executed.  The case of iretq faulting due to the invalid usermode
context is tricky, since the frame for fault is appended to the
trampoline frame.  Besides copying the fault frame and original
(corrupted) frame to kstack, the fault frame must be patched to make
it look as if the fault occured on the kstack, see the comment in
doret_iret detection code in trap().

Currently kernel pages which are mapped during trampoline operation
are identical for all pmaps.  They are registered using
pmap_pti_add_kva().  Besides initial registrations done during boot,
LDT and non-common TSS segments are registered if user requested their
use.  In principle, they can be installed into kernel page table per
pmap with some work.  Similarly, PCPU can be hidden from userspace
mapping using trampoline PCPU page, but again I do not see much
benefits besides complexity.

PDPE pages for the kernel half of the user page tables are
pre-allocated during boot because we need to know pml4 entries which
are copied to the top-level paging structure page, in advance on a new
pmap creation.  I enforce this to avoid iterating over the all
existing pmaps if a new PDPE page is needed for PTI kernel mappings.
The iteration is a known problematic operation on i386.

The need to flush hidden kernel translations on the switch to user
mode make global tables (PG_G) meaningless and even harming, so PG_G
use is disabled for PTI case.  Our existing use of PCID is
incompatible with PTI and is automatically disabled if PTI is
enabled.  PCID can be forced on only for developer's benefit.

MCE is known to be broken, it requires IST stack to operate completely
correctly even for non-PTI case, and absolutely needs dedicated IST
stack because MCE delivery while trampoline did not switched from PTI
stack is fatal.  The fix is pending.

Reviewed by:	markj (partially)
Tested by:	pho (previous version)
Discussed with:	jeff, jhb
Sponsored by:	The FreeBSD Foundation
MFC after:	2 weeks
2018-01-17 11:44:21 +00:00