Commit Graph

13426 Commits

Author SHA1 Message Date
Yuri Pankov
a161fba992 linux: futex_mtx should follow futex_list
Move futex_mtx to linux_common.ko for amd64 and aarch64 along
with respective list/mutex init/destroy.

PR:		240989
Reported by:	Alex S <iwtcex@gmail.com>
2019-10-18 12:25:33 +00:00
Conrad Meyer
dda17b3672 Implement NetGDB(4)
NetGDB(4) is a component of a system using a panic-time network stack to
remotely debug crashed FreeBSD kernels over the network, instead of
traditional serial interfaces.

There are three pieces in the complete NetGDB system.

First, a dedicated proxy server must be running to accept connections from
both NetGDB and gdb(1), and pass bidirectional traffic between the two
protocols.

Second, the NetGDB client is activated much like ordinary 'gdb' and
similarly to 'netdump' in ddb(4) after a panic.  Like other debugnet(4)
clients (netdump(4)), the network interface on the route to the proxy server
must be online and support debugnet(4).

Finally, the remote (k)gdb(1) uses 'target remote <proxy>:<port>' (like any
other TCP remote) to connect to the proxy server.

The NetGDB v1 protocol speaks the literal GDB remote serial protocol, and
uses a 1:1 relationship between GDB packets and sequences of debugnet
packets (fragmented by MTU).  There is no encryption utilized to keep
debugging sessions private, so this is only appropriate for local
segments or trusted networks.

Submitted by:	John Reimer <john.reimer AT emc.com> (earlier version)
Discussed some with:	emaste, markj
Relnotes:	sure
Differential Revision:	https://reviews.freebsd.org/D21568
2019-10-17 21:33:01 +00:00
Conrad Meyer
7790c8c199 Split out a more generic debugnet(4) from netdump(4)
Debugnet is a simplistic and specialized panic- or debug-time reliable
datagram transport.  It can drive a single connection at a time and is
currently unidirectional (debug/panic machine transmit to remote server
only).

It is mostly a verbatim code lift from netdump(4).  Netdump(4) remains
the only consumer (until the rest of this patch series lands).

The INET-specific logic has been extracted somewhat more thoroughly than
previously in netdump(4), into debugnet_inet.c.  UDP-layer logic and up, as
much as possible as is protocol-independent, remains in debugnet.c.  The
separation is not perfect and future improvement is welcome.  Supporting
INET6 is a long-term goal.

Much of the diff is "gratuitous" renaming from 'netdump_' or 'nd_' to
'debugnet_' or 'dn_' -- sorry.  I thought keeping the netdump name on the
generic module would be more confusing than the refactoring.

The only functional change here is the mbuf allocation / tracking.  Instead
of initiating solely on netdump-configured interface(s) at dumpon(8)
configuration time, we watch for any debugnet-enabled NIC for link
activation and query it for mbuf parameters at that time.  If they exceed
the existing high-water mark allocation, we re-allocate and track the new
high-water mark.  Otherwise, we leave the pre-panic mbuf allocation alone.
In a future patch in this series, this will allow initiating netdump from
panic ddb(4) without pre-panic configuration.

No other functional change intended.

Reviewed by:	markj (earlier version)
Some discussion with:	emaste, jhb
Objection from:	marius
Differential Revision:	https://reviews.freebsd.org/D21421
2019-10-17 16:23:03 +00:00
Mark Johnston
01cef4caa7 Remove page locking from pmap_mincore().
After r352110 the page lock no longer protects a page's identity, so
there is no purpose in locking the page in pmap_mincore().  Instead,
if vm.mincore_mapped is set to the non-default value of 0, re-lookup
the page after acquiring its object lock, which holds the page's
identity stable.

The change removes the last callers of vm_page_pa_tryrelock(), so
remove it.

Reviewed by:	kib
Sponsored by:	Netflix
Differential Revision:	https://reviews.freebsd.org/D21823
2019-10-16 22:03:27 +00:00
Andriy Gapon
edca4938f7 itwd(4): driver for watchdog function in ITE Super I/O chips
The chips are commonly named with "IT" prefix.

MFC after:	19 days
2019-10-16 14:57:38 +00:00
Jeff Roberson
638f867814 (6/6) Convert pmap to expect busy in write related operations now that all
callers hold it.

This simplifies pmap code and removes a dependency on the object lock.

Reviewed by:    kib, markj
Tested by:      pho
Sponsored by:   Netflix, Intel
Differential Revision:	https://reviews.freebsd.org/D21596
2019-10-15 03:51:46 +00:00
Jeff Roberson
205be21d99 (3/6) Add a shared object busy synchronization mechanism that blocks new page
busy acquires while held.

This allows code that would need to acquire and release a very large number
of page busy locks to use the old mechanism where busy is only checked and
not held.  This comes at the cost of false positives but never false
negatives which the single consumer, vm_fault_soft_fast(), handles.

Reviewed by:    kib
Tested by:      pho
Sponsored by:   Netflix, Intel
Differential Revision:	https://reviews.freebsd.org/D21592
2019-10-15 03:41:36 +00:00
Andriy Gapon
db8bee42ce i386: hide more of atomic 64-bit definitions under _KERNEL
At the moment i386 does not provide 64-bit atomic operations in
userland.  Exposing some atomic_*_64 defines can cause unnecessary
confusion.

Discussed with:	kib
MFC after:	2 weeks
2019-10-08 10:50:16 +00:00
Ed Maste
9923b64177 Remove host binary object drivers from GENERIC
Four drivers (hpt27xx, hptmv, hptnr, hptrr, hpt27xx) include precompiled
binary objects; have users load them as modules if they are needed.

Additional work (i.e., integrating devmatch) required before MFC.

Reviewed by:	markj
Relnotes:	Yes
Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D21865
2019-10-03 12:51:57 +00:00
Konstantin Belousov
df08823d07 Improve MD page fault handlers.
Centralize calculation of signal and ucode delivered on unhandled page
fault in new function vm_fault_trap().  MD trap_pfault() now almost
always uses the signal numbers and error codes calculated in
consistent MI way.

This introduces the protection fault compatibility sysctls to all
non-x86 architectures which did not have that bug, but apparently they
were already much more wrong in selecting delivered signals on
protection violations.

Change the delivered signal for accesses to mapped area after the
backing object was truncated.  According to POSIX description for
mmap(2):
   The system shall always zero-fill any partial page at the end of an
   object. Further, the system shall never write out any modified
   portions of the last page of an object which are beyond its
   end. References within the address range starting at pa and
   continuing for len bytes to whole pages following the end of an
   object shall result in delivery of a SIGBUS signal.

   An implementation may generate SIGBUS signals when a reference
   would cause an error in the mapped object, such as out-of-space
   condition.
Adjust according to the description, keeping the existing
compatibility code for SIGSEGV/SIGBUS on protection failures.

For situations where kernel cannot handle page fault due to resource
limit enforcement, SIGBUS with a new error code BUS_OBJERR is
delivered.  Also, provide a new error code SEGV_PKUERR for SIGSEGV on
amd64 due to protection key access violation.

vm_fault_hold() is renamed to vm_fault().  Fixed some nits in
trap_pfault()s like mis-interpreting Mach errors as errnos.  Removed
unneeded truncations of the fault addresses reported by hardware.

PR:	211924
Reviewed by:	alc
Discussed with:	jilles, markj
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
Differential revision:	https://reviews.freebsd.org/D21566
2019-09-27 18:43:36 +00:00
Kyle Evans
d19f028e33 sysent: regenerate after r352693 2019-09-25 17:30:28 +00:00
Mark Johnston
b119329d81 Complete the removal of the "wire_count" field from struct vm_page.
Convert all remaining references to that field to "ref_count" and update
comments accordingly.  No functional change intended.

Reviewed by:	alc, kib
Sponsored by:	Intel, Netflix
Differential Revision:	https://reviews.freebsd.org/D21768
2019-09-25 16:11:35 +00:00
Konstantin Belousov
66eb1d6347 i386: reduce differences in source between PAE and non-PAE pmaps ...
by defining pg_nx as zero for non-PAE and correspondingly simplifying
some expressions.

Suggested and reviewed by:	markj
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
Differential revision:	https://reviews.freebsd.org/D21757
2019-09-22 19:59:10 +00:00
Konstantin Belousov
b223a69238 i386: implement sysctl vm.pmap.kernel_maps.
Reviewed by:	markj
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
Differential revision:	https://reviews.freebsd.org/D21739
2019-09-22 19:23:00 +00:00
Mark Johnston
e8bcf6966b Revert r352406, which contained changes I didn't intend to commit. 2019-09-16 15:04:45 +00:00
Mark Johnston
41fd4b9422 Fix a couple of nits in r352110.
- Remove a dead variable from the amd64 pmap_extract_and_hold().
- Fix grammar in the vm_page_wire man page.

Reported by:	alc
Reviewed by:	alc, kib
Sponsored by:	Netflix
Differential Revision:	https://reviews.freebsd.org/D21639
2019-09-16 15:03:12 +00:00
Ed Maste
a8ce8f0ae5 Update comments and ordering in linux*_dummy.c
- sort alphabetically
- getcpu arrived in Linux 2.6.19
- fanotify_* arrived in 2.6.36
2019-09-11 17:56:48 +00:00
Ed Maste
eff9d7b799 linuxulator: memfd_create first appeared in Linux 3.17
Reference: http://man7.org/linux/man-pages/man2/memfd_create.2.html
2019-09-11 17:05:49 +00:00
Ed Maste
1515fe49f2 linuxulator: seccomp syscall first appeared in Linux 3.17
Reference: http://man7.org/linux/man-pages/man2/seccomp.2.html
2019-09-11 17:04:13 +00:00
Ed Maste
2eb6ef203a linux: add trivial renameat2 implementation
Just return EINVAL if flags != 0.  The Linux man page documents one
case of EINVAL as "The filesystem does not support one of the flags in
flags."

After r351723 userland binaries will try using new system calls.

Reported by:	mjg
Reviewed by:	mjg, trasz
Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D21590
2019-09-11 13:01:59 +00:00
Ed Maste
65ab1fdd21 regen linuxulator sysent after r352208 2019-09-11 12:58:53 +00:00
Ed Maste
427b1baec0 make linux_renameat2 args consistent with linux_renameat
Use 'dfd' consistently for a directory fd.
2019-09-11 12:58:06 +00:00
Mark Johnston
fee2a2fa39 Change synchonization rules for vm_page reference counting.
There are several mechanisms by which a vm_page reference is held,
preventing the page from being freed back to the page allocator.  In
particular, holding the page's object lock is sufficient to prevent the
page from being freed; holding the busy lock or a wiring is sufficent as
well.  These references are protected by the page lock, which must
therefore be acquired for many per-page operations.  This results in
false sharing since the page locks are external to the vm_page
structures themselves and each lock protects multiple structures.

Transition to using an atomically updated per-page reference counter.
The object's reference is counted using a flag bit in the counter.  A
second flag bit is used to atomically block new references via
pmap_extract_and_hold() while removing managed mappings of a page.
Thus, the reference count of a page is guaranteed not to increase if the
page is unbusied, unmapped, and the object's write lock is held.  As
a consequence of this, the page lock no longer protects a page's
identity; operations which move pages between objects are now
synchronized solely by the objects' locks.

The vm_page_wire() and vm_page_unwire() KPIs are changed.  The former
requires that either the object lock or the busy lock is held.  The
latter no longer has a return value and may free the page if it releases
the last reference to that page.  vm_page_unwire_noq() behaves the same
as before; the caller is responsible for checking its return value and
freeing or enqueuing the page as appropriate.  vm_page_wire_mapped() is
introduced for use in pmap_extract_and_hold().  It fails if the page is
concurrently being unmapped, typically triggering a fallback to the
fault handler.  vm_page_wire() no longer requires the page lock and
vm_page_unwire() now internally acquires the page lock when releasing
the last wiring of a page (since the page lock still protects a page's
queue state).  In particular, synchronization details are no longer
leaked into the caller.

The change excises the page lock from several frequently executed code
paths.  In particular, vm_object_terminate() no longer bounces between
page locks as it releases an object's pages, and direct I/O and
sendfile(SF_NOCACHE) completions no longer require the page lock.  In
these latter cases we now get linear scalability in the common scenario
where different threads are operating on different files.

__FreeBSD_version is bumped.  The DRM ports have been updated to
accomodate the KPI changes.

Reviewed by:	jeff (earlier version)
Tested by:	gallatin (earlier version), pho
Sponsored by:	Netflix
Differential Revision:	https://reviews.freebsd.org/D20486
2019-09-09 21:32:42 +00:00
Konstantin Belousov
04359b5e1e Remove useless redefinition of NSFBUFS in i386/vm_machdep.c.
Sponsored by:	The FreeBSD Foundation
2019-08-29 07:34:14 +00:00
Konstantin Belousov
a2a0f90654 Centralize __pcpu definitions.
Many extern struct pcpu <something>__pcpu declarations were
copied/pasted in sources.  The issue is that the definition is MD, but
it cannot be provided by machine/pcpu.h due to actual struct pcpu
defined in sys/pcpu.h later than the inclusion of machine/pcpu.h.
This forced the copying when other code needed direct access to
__pcpu.  There is no way around it, due to machine/pcpu.h supplying
part of struct pcpu fields.

To work around the problem, add a new machine/pcpu_aux.h header, which
should fill any needed MD definitions after struct pcpu definition is
completed. This allows to remove copies of __pcpu spread around the
source.  Also on x86 it makes it possible to remove work arounds like
OFFSETOF_CURTHREAD or clang specific warnings supressions.

Reported and tested by:	lwhsu, bcran
Reviewed by:	imp, markj (previous version)
Discussed with:	jhb
Sponsored by:	The FreeBSD Foundation
Differential revision:	https://reviews.freebsd.org/D21418
2019-08-29 07:25:27 +00:00
Konstantin Belousov
3a91d1062a i386: Implement atomic_load_64(9) and atomic_store_64(9).
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
2019-08-18 15:58:44 +00:00
Jeff Roberson
2194393787 Move phys_avail definition into MI code. It is consumed in the MI layer and
doing so adds more flexibility with less redundant code.

Reviewed by:	jhb, markj, kib
Sponsored by:	Netflix
Differential Revision:	https://reviews.freebsd.org/D21250
2019-08-16 00:45:14 +00:00
Warner Losh
0d89c934cb Start to split out the really x86 specific NOTES from the global notes file.
Start with COMPAT_43, since it's really only relevant to x86.

Reviewed by: jhb@
Differential Revision: https://reviews.freebsd.org/D21203
2019-08-12 22:58:13 +00:00
John Baldwin
a04725cd5c Detect invalid PCI devices more correctly in PCI interrupt router drivers.
- Check for an invalid device (vendor is invalid) before reading the
  header type register when examining function 0 of a possible device.
- When iterating over functions of a device, reject any device whose
  16-bit vendor is invalid rather than requiring the full 32-bit
  vendor+device to be all 1's.  In practice the latter check is
  probably fine, but checking the vendor is what the PCI spec
  recommends.

Reviewed by:	imp
MFC after:	2 weeks
Differential Revision:	https://reviews.freebsd.org/D21147
2019-08-06 23:15:04 +00:00
John Baldwin
c45cbc7a1f Don't reset memory attributes when mapping physical addresses for ACPI.
Previously, AcpiOsMemory was using pmap_mapbios which would always map
the requested address Write-Back (WB).  For several AMD Ryzen laptops,
the BIOS uses AcpiOsMemory to directly access the PCI MCFG region in
order to access PCI config registers.  This has the side effect of
remapping the MCFG region in the direct map as WB instead of UC
hanging the laptops during boot.

On the one laptop I examined in detail, the _PIC global method used to
switch from 8259A PICs to I/O APICs uses a pair of PCI config space
registers at offset 0x84 in the device at 0:0:0 to as a pair of
address/data registers to access an indirect register in the chipset
and clear a single bit to switch modes.

To fix, alter the semantics of pmap_mapbios() such that it does not
modify the attributes of any existing mappings and instead uses the
existing attributes.  If a new mapping is created, this new mapping
uses WB (the default memory attribute).

Special thanks to the gentleman whose name I don't have who brought
two affected laptops to the hacker lounge at BSDCan.  Direct access to
the affected systems permitted finding the root cause within an hour
or so.

PR:		231760, 236899
Reviewed by:	kib, alc
MFC after:	2 weeks
Differential Revision:	https://reviews.freebsd.org/D20327
2019-08-03 01:36:05 +00:00
Alan Cox
43ded0a321 In pmap_advise(), when we encounter a superpage mapping, we first demote the
mapping and then destroy one of the 4 KB page mappings so that there is a
potential trigger for repromotion.  Currently, we destroy the first 4 KB
page mapping that falls within the (current) superpage mapping or the
virtual address range [sva, eva).  However, I have found empirically that
destroying the last 4 KB mapping produces slightly better results,
specifically, more promotions and fewer failed promotion attempts.
Accordingly, this revision changes pmap_advise() to destroy the last 4 KB
page mapping.  It also replaces some nearby uses of boolean_t with bool.

Reviewed by:	kib, markj
Differential Revision:	https://reviews.freebsd.org/D21115
2019-07-31 05:38:39 +00:00
Ed Maste
305b9efefc linuxulator: rename linux_locore.s to .asm
It is assembled using "${CC} -x assembler-with-cpp", which by convention
(bsd.suffixes.mk) uses the .asm extension.

This is a portion of the review referenced below (D18344).  That review
also renamed linux_support.s to .S, but that is a functional change
(using the compiler's integrated assembler instead of as) and will be
revisited separately.

MFC after:	1 week
Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D18344
2019-07-30 17:18:31 +00:00
Xin LI
d4565741c6 Remove gzip'ed a.out support.
The current implementation of gzipped a.out support was based
on a very old version of InfoZIP which ships with an ancient
modified version of zlib, and was removed from the GENERIC
kernel in 1999 when we moved to an ELF world.

PR:		205822
Reviewed by:	imp, kib, emaste, Yoshihiro Ota <ota at j.email.ne.jp>
Relnotes:	yes
Differential Revision:	https://reviews.freebsd.org/D21099
2019-07-30 05:13:16 +00:00
Alan Cox
5d18382b72 Simplify the handling of superpages in pmap_clear_modify(). Specifically,
if a demotion succeeds, then all of the 4KB page mappings within the
superpage-sized region must be valid, so there is no point in testing the
validity of the 4KB page mapping that is going to be write protected.

Deindent the nearby code.

Reviewed by:	kib, markj
Tested by:	pho (amd64, i386)
X-MFC after:	r350004 (this change depends on arm64 dirty bit emulation)
Differential Revision:	https://reviews.freebsd.org/D21027
2019-07-25 22:02:55 +00:00
Alan Cox
43184d8e5c Revert r349973. Upon further reflection, I realized that the comment
deleted by r349973 is still valid on i386.  Restore it.

Discussed with:	   markj
2019-07-16 03:09:03 +00:00
John Baldwin
c18ca74916 Don't pass error from syscallenter() to syscallret().
syscallret() doesn't use error anymore.  Fix a few other places to permit
removing the return value from syscallenter() entirely.
- Remove a duplicated assertion from arm's syscall().
- Use td_errno for amd64_syscall_ret_flush_l1d.

Reviewed by:	kib
MFC after:	1 month
Sponsored by:	DARPA
Differential Revision:	https://reviews.freebsd.org/D2090
2019-07-15 21:25:16 +00:00
Alan Cox
f138406359 Remove a stale comment.
Reported by:	markj
MFC after:	1 week
2019-07-13 15:53:28 +00:00
Konstantin Belousov
30b3018d48 Provide protection against starvation of the ll/sc loops when accessing userpace.
Casueword(9) on ll/sc architectures must be prepared for userspace
constantly modifying the same cache line as containing the CAS word,
and not loop infinitely.  Otherwise, rogue userspace livelocks the
kernel.

To fix the issue, change casueword(9) interface to return new value 1
indicating that either comparision or store failed, instead of relying
on the oldval == *oldvalp comparison.  The primitive no longer retries
the operation if it failed spuriously.  Modify callers of
casueword(9), all in kern_umtx.c, to handle retries, and react to
stops and requests to terminate between retries.

On x86, despite cmpxchg should not return spurious failures, we can
take advantage of the new interface and just return PSL.ZF.

Reviewed by:	andrew (arm64, previous version), markj
Tested by:	pho
Reported by:	https://xenbits.xen.org/xsa/advisory-295.txt
Sponsored by:	The FreeBSD Foundation
MFC after:	2 weeks
Differential revision:	https://reviews.freebsd.org/D20772
2019-07-12 18:43:24 +00:00
Mark Johnston
eeacb3b02f Merge the vm_page hold and wire mechanisms.
The hold_count and wire_count fields of struct vm_page are separate
reference counters with similar semantics.  The remaining essential
differences are that holds are not counted as a reference with respect
to LRU, and holds have an implicit free-on-last unhold semantic whereas
vm_page_unwire() callers must explicitly determine whether to free the
page once the last reference to the page is released.

This change removes the KPIs which directly manipulate hold_count.
Functions such as vm_fault_quick_hold_pages() now return wired pages
instead.  Since r328977 the overhead of maintaining LRU for wired pages
is lower, and in many cases vm_fault_quick_hold_pages() callers would
swap holds for wirings on the returned pages anyway, so with this change
we remove a number of page lock acquisitions.

No functional change is intended.  __FreeBSD_version is bumped.

Reviewed by:	alc, kib
Discussed with:	jeff
Discussed with:	jhb, np (cxgbe)
Tested by:	pho (previous version)
Sponsored by:	Netflix
Differential Revision:	https://reviews.freebsd.org/D19247
2019-07-08 19:46:20 +00:00
Alexander Motin
6683132d54 Add driver for NTB in AMD SoC.
This patch is the driver for NTB hardware in AMD SoCs (ported from Linux)
and enables the NTB infrastructure like Doorbells, Scratchpads and Memory
window in AMD SoC. This driver has been validated using ntb_transport and
if_ntb driver already available in FreeBSD.

Submitted by:	Rajesh Kumar <rajesh1.kumar@amd.com>
MFC after:	1 month
Relnotes:	yes
Differential Revision:	https://reviews.freebsd.org/D18774
2019-07-02 05:25:18 +00:00
Andriy Gapon
e3722b788e add superio driver
The goal of this driver is consolidate information about SuperIO chips
and to provide for peaceful coexistence of drivers that need to access
SuperIO configuration registers.

While SuperIO chips can host various functions most of them are
discoverable and accessible without any knowledge of the SuperIO.
Examples are: keyboard and mouse controllers, UARTs, floppy disk
controllers.  SuperIO-s also provide non-standard functions such as
GPIO, watchdog timers and hardware monitoring.  Such functions do
require drivers with a knowledge of a specific SuperIO.

At this time the driver supports a number of ITE and Nuvoton (fka
Winbond) SuperIO chips.
There is a single driver for all devices.  So, I have not done the usual
split between the hardware driver and the bus functionality.  Although,
superio does act as a bus for devices that represent known non-standard
functions of a SuperIO chip.  The bus provides enumeration of child
devices based on the hardcoded knowledge of such functions.  The
knowledge as extracted from datasheets and other drivers.
As there is a single driver, I have not defined a kobj interface for it.
So, its interface is currently made of simple functions.
I think that we can the flexibility (and complications) when we actually
need it.

I am planning to convert nctgpio and wbwd to superio bus very soon.
Also, I am working on itwd driver (watchdog in ITE SuperIO-s).
Additionally, there is ithwm driver based on the reverted sensors
import, but I am not sure how to integrate it given that we still lack
any sensors interface.

Discussed with:	imp, jhb
MFC after:	7 weeks
Differential Revision: https://reviews.freebsd.org/D8175
2019-07-01 17:05:41 +00:00
Navdeep Parhar
57f317e60a Display the approximate space needed when a minidump fails due to lack
of space.

Reviewed by:	kib@
MFC after:	2 weeks
Sponsored by:	Chelsio Communications
Differential Revision:	https://reviews.freebsd.org/D20801
2019-06-30 03:14:04 +00:00
Alan Cox
c134ef742f When we protect PTEs (as opposed to PDEs), we only call vm_page_dirty()
when, in fact, we are write protecting the page and the PTE has PG_M set.
However, pmap_protect_pde() was always calling vm_page_dirty() when the PDE
has PG_M set.  So, adding PG_NX to a writeable PDE could result in
unnecessary (but harmless) calls to vm_page_dirty().

Simplify the loop calling vm_page_dirty() in pmap_protect_pde().

Reviewed by:	kib, markj
MFC after:	1 week
Differential Revision:	https://reviews.freebsd.org/D20793
2019-06-28 22:40:34 +00:00
Conrad Meyer
c363b16c63 sys: Remove DEV_RANDOM device option
Remove 'device random' from kernel configurations that reference it (most).
Replace perhaps mistaken 'nodevice random' in two MIPS configs with 'options
RANDOM_LOADABLE' instead.  Document removal in UPDATING; update NOTES and
random.4.

Reviewed by:	delphij, markm (previous version)
Approved by:	secteam(delphij)
Differential Revision:	https://reviews.freebsd.org/D19918
2019-06-21 00:16:30 +00:00
Alan Cox
fd2dae0a30 Implement an alternative solution to the amd64 and i386 pmap problem that we
previously addressed in r348246.

This pmap problem also exists on arm64 and riscv.  However, the original
solution developed for amd64 and i386 cannot be used on arm64 and riscv.  In
particular, arm64 and riscv do not define a PG_PROMOTED flag in their level
2 PTEs.  (A PG_PROMOTED flag makes no sense on arm64, where unlike x86 or
riscv we are required to break the old 4KB mappings before making the 2MB
mapping; and on riscv there are no unused bits in the PTE to define a
PG_PROMOTED flag.)

This commit implements an alternative solution that can be used on all four
architectures.  Moreover, this solution has two other advantages.  First, on
older AMD processors that required the Erratum 383 workaround, it is less
costly.  Specifically, it avoids unnecessary calls to pmap_fill_ptp() on a
superpage demotion.  Second, it enables the elimination of some calls to
pagezero() in pmap_kernel_remove_{l2,pde}().

In addition, remove a related stale comment from pmap_enter_{l2,pde}().

Reviewed by:	kib, markj (an earlier version)
MFC after:	1 week
Differential Revision:	https://reviews.freebsd.org/D20538
2019-06-09 03:36:10 +00:00
Konstantin Belousov
c46d985629 i386 trap.c: Remove unused MAX_TRAP_MSG define.
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
2019-06-08 13:41:39 +00:00
Mark Johnston
88ea538a98 Replace uses of vm_page_unwire(m, PQ_NONE) with vm_page_unwire_noq(m).
These calls are not the same in general: the former will dequeue the
page if it is enqueued, while the latter will just leave it alone.  But,
all existing uses of the former apply to unmanaged pages, which are
never enqueued in the first place.  No functional change intended.

Reviewed by:	kib
MFC after:	1 week
Sponsored by:	Netflix
Differential Revision:	https://reviews.freebsd.org/D20470
2019-06-07 18:23:29 +00:00
Mark Johnston
c080655467 Fix a race between fasttrap and the user breakpoint handler.
When disabling the last enabled userspace probe, fasttrap clears the
function pointers which hook in to the breakpoint handler.  If a traced
thread hit a fasttrap breakpoint before it was removed, we must ensure
that it is able to call the hook; otherwise fasttrap will not consume
the trap and SIGTRAP will be delievered to the thread.  Synchronize
with such threads by ensuring that they load the hook pointer with
interrupts disabled, and by completing an SMP rendezvous after removing
breakpoints and before clearing the pointers.

Reported by:	Alexander Alexeev <Alexander.Alexeev@dell.com>
Tested by:	Alexander Alexeev (earlier version)
Reviewed by:	cem, kib
MFC after:	1 week
Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D20526
2019-06-06 16:03:25 +00:00
Brooks Davis
4af6033324 makesyscalls.sh: always use absolute path for syscalls.conf
syscalls.conf is included using "." which per the Open Group:

 If file does not contain a <slash>, the shell shall use the search
 path specified by PATH to find the directory containing file.

POSIX shells don't fall back to the current working directory.

Submitted by:	Nathaniel Wesley Filardo <nwf20@cl.cam.ac.uk>
Reviewed by:	bdrewery
Sponsored by:	DARPA, AFRL
Differential Revision:	https://reviews.freebsd.org/D20476
2019-05-30 20:56:23 +00:00
Pedro F. Giffuni
ec845b07c6 typo: suppported. 2019-05-29 02:08:23 +00:00