imcsmb(4) provides smbus(4) support for the SMBus controller functionality
in the integrated Memory Controllers (iMCs) embedded in Intel Sandybridge-
Xeon, Ivybridge-Xeon, Haswell-Xeon, and Broadwell-Xeon CPUs. Each CPU
implements one or more iMCs, depending on the number of cores; each iMC
implements two SMBus controllers (iMC-SMBs).
*** IMPORTANT NOTE ***
Because motherboard firmware or the BMC might try to use the iMC-SMBs for
monitoring DIMM temperatures and/or managing an NVDIMM, the driver might
need to temporarily disable those functions, or take a hardware interlock,
before using the iMC-SMBs. Details on how to do this may vary from board to
board, and the procedure may be proprietary. It is strongly suggested that
anyone wishing to use this driver contact their motherboard vendor, and
modify the driver as described in the manual page and in the driver itself.
(For what it's worth, the driver as-is has been tested on various SuperMicro
motherboards.)
Reviewed by: avg, jhb
MFC after: 1 week
Relnotes: yes
Sponsored by: Panasas
Differential Revision: https://reviews.freebsd.org/D14447
Discussed with: avg, ian, jhb
Tested by: allanjude (previous version), Panasas
camelCase tends to be preferred for function identifiers, while
internal_underscores are preferred for variable identifiers. This convention
makes it a little bit easier to eyeball whether variable/function usage is
correct.
The optional commas for final table values are preferred to reduce chances
for error.
A super-set of the functionality of jedec_ts(4). jedec_dimm(4) reports asset
information (Part Number, Serial Number) encoded in the "Serial Presence
Detect" (SPD) data on JEDEC DDR3 and DDR4 DIMMs. It also calculates and
reports the memory capacity of the DIMM, in megabytes. If the DIMM includes
a "Thermal Sensor On DIMM" (TSOD), the temperature is also reported.
Reviewed by: cem
MFC after: 1 week
Relnotes: yes
Sponsored by: Panasas
Differential Revision: https://reviews.freebsd.org/D14392
Discussed with: avg, cem
Tested by: avg, cem (previous version, no semantic changes)
Add chvgpio(4) driver for Intel Z8xxx SoC family. This product
was formerly known as Cherry Trail but Linux and OpenBSD drivers
refer to it as Cherry View. This driver is derived from OpenBSD
one so the name is kept for alignment with another BSD system.
Submitted by: Tom Jones <tj@enoti.me>
Reviewed by: gonzo, wblock(man page)
MFC after: 2 weeks
Differential Revision: https://reviews.freebsd.org/D13086
The intent of this guideline is to avoid creating global variables in module
scope. Its main purpose is to serve as a reminder that variables at module
scope also need to be declared.
We want to avoid global variables in general, but this is easier to mess up
when designing things in the module scope.
VirtIO V1 provides configuration in multiple VENDOR capabilities so this
allows all of the configuration to be discovered.
Reviewed by: jhb
MFC after: 2 weeks
Differential Revision: https://reviews.freebsd.org/D14325
This covers the lua style guidelines we've generally agreed on so far. It
will be revised as work continues and we run into more scenarios that need
specified.
Discussed with: cem, jilles
Differential Revision: https://reviews.freebsd.org/D14423
A few ISP filter PADI requests based on such tag,
to force the use of their own routers.
The custom Host-Uniq tag is passed in the NGM_PPPOE_CONNECT
control message, so it can be used with FreeBSD ppp(8)
and mpd without any other change.
Add support to send and receive PADM messages,
HURL and MOTM, often used by service providers to provide
ACS information and other configuration settings
to the user CPE.
Submitted by: ale
Approved by: mav (mentor)
MFC after: 1 month
Differential Revision: https://reviews.freebsd.org/D9270
This works similarly to the existing gzip compression support, but
zstd is typically faster and gives better compression ratios.
Support for this functionality must be configured by adding ZSTDIO to
one's kernel configuration file. dumpon(8)'s new -Z option is used to
configure zstd compression for kernel dumps. savecore(8) now recognizes
and saves zstd-compressed kernel dumps with a .zst extension.
Submitted by: cem (original version)
Relnotes: yes
Sponsored by: Dell EMC Isilon
Differential Revision: https://reviews.freebsd.org/D13101,
https://reviews.freebsd.org/D13633
Using args[2]->tcps_state as-documented results in error:
operator -> cannot be applied to pointer to type "void"
This error is accurate as the synopsis for tcp:::state-change is:
tcp:::state-change(void *, csinfo_t *, void *, tcpsinfo_t *, void *,
tcplsinfo_t *);
args[2] refers to the third argument which is always NULL (as-
documented). The to-state for the TCP connection state transition is
actually in the fourth argument, args[3]->tcps_state.
- Remove the shim interface that allowed bwn(4) to use either siba_bwn or
bhnd(4), replacing all siba_bwn calls with their bhnd(4) bus equivalents.
- Drop the legay, now-unused siba_bwn bus driver.
- Clean up bhnd(4) board flag defines referenced by bwn(4).
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D13518
Our standard boot method for arm64 is via UEFI, so install the man page
that describes the boot process.
MFC after: 1 week
Sponsored by: The FreeBSD Foundation
FreeBSD and industry has been inconsistent in the use of UEFI and EFI.
They are essentially just different versions of the same specification
and are often used interchangeably. Make it easier for users to find
information by making efi(8) an alias for uefi(8).
Reported by: imp, jhb
- EFI support appeared in 5.0 for ia64
- arm64 UEFI support added in 11.0
The AUTHORS section included the folks responsible for the bulk of the
work to bring UEFI support to amd64, but missed those who did the
original work on ia64, the initial port to i386, the ports to arm64 and
arm, and have generally maintained and improved general UEFI support
since then. It's unwieldly to include everyone and would quickly become
outdated again anyhow, so just remove the AUTHORS section.
Reviewed by: manu
Discussed with: jhb
Differential Revision: https://reviews.freebsd.org/D14033
possible to change string and numeric vendor and product identifiers,
as well as anything else there might be to change for a particular
device side template, eg the MAC address.
Reviewed by: hselasky@
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D13920
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
r314467 introduced hw.usb.wsp.enable_single_tap_clicks to enable/disable
single-tap left click behavior. Update the man page to reflect the new
sysctl.
PR: 196624
MFC after: 3 days
X-MFC-With: r314467
Attaching syscon_generic earlier than BUS_PASS_DEFAULT makes it more
difficult for specific syscon drivers to attach to the syscon node and to
get ordering right. Further discussion yielded the following set of
decisions:
- Move syscon_generic to BUS_PASS_DEFAULT
- If a platform needs a syscon with different attach order or probe
behavior, it should subclass syscon_generic and match on the SoC specific
compat string
- When we come across a need for a syscon that attaches earlier but only
specifies compatible = "syscon", we should create a syscon_exclusive driver
that provides generic access but probes earlier and only matches if "syscon"
is the only compatible. Such fdt nodes do exist in the wild right now, but
we don't really use them at the moment.
Additionally:
- Any syscon provider that has needs any more complex than a spinlock solely
for syscon access and a single memory resource should subclass syscon
directly rather than attempting to subclass syscon_generic or add complexity
to it. syscon_generic's attach/detach methods may be made public should the
need arise to subclass it with additional attach/detach behavior.
We introduce aw_syscon(4) that just subclasses syscon_generic but probes
earlier to meet our requirements for if_awg and implements #2 above for this
specific situation. It currently only matches a64/a83t/h3 since these are
the only platforms that really need it at the time being.
Discussed with: ian
Reviewed by: manu, andrew, bcr (manpages, content unchanged since review)
Differential Revision: https://reviews.freebsd.org/D13793
There's a report of some regression in ports. Revert for now for an
exp run for this change in isolation (previous lld exp run also included
switching the linker used for ports to lld).
Also revert the src.conf.5 regeneration in r327824.
Reported by: antoine
Sponsored by: The FreeBSD Foundation
Additionally, move the overflow check logic out to WOULD_OVERFLOW() for
consumers to have a common means of testing for overflowing allocations.
WOULD_OVERFLOW() should be a secondary check -- on 64-bit platforms, just
because an allocation won't overflow size_t does not mean it is a sane size
to request. Callers should be imposing reasonable allocation limits far,
far, below overflow.
Discussed with: emaste, jhb, kp
Sponsored by: Dell EMC Isilon
(I missed the Reviewed by and review link from r327783.)
Reviewed by: brooks, dim, bapt
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D13827
We currently use a set of subroutines in kern_gzio.c to perform
compression of user and kernel core dumps. In the interest of adding
support for other compression algorithms (zstd) in this role without
complicating the API consumers, add a simple compressor API which can be
used to select an algorithm.
Also change the (non-default) GZIO kernel option to not enable
compressed user cores by default. It's not clear that such a default
would be desirable with support for multiple algorithms implemented,
and it's inconsistent in that it isn't applied to kernel dumps.
Reviewed by: cem
Differential Revision: https://reviews.freebsd.org/D13632
Similar to calloc() the mallocarray() function checks for integer
overflows before allocating memory.
It does not zero memory, unless the M_ZERO flag is set.
Reviewed by: pfg, vangyzen (previous version), imp (previous version)
Obtained from: OpenBSD
Differential Revision: https://reviews.freebsd.org/D13766
The sid controller on the H3 is generally identical in location, size, and
efuse offset to the a64 and the a83t. The main difference is that the H3 has
a silicon bug that sometimes causes the rootkey (at least) to be garbled
unless first read by the prctl registers.
This device is currently not in our DTS and, as of now, is not yet present
in mainline Linux DTS.
Tested on: OrangePi One
Enable the hardclock-based watchdog previously conditional on the
SW_WATCHDOG option whenever hardware watchdogs are not found, and
watchdogd attempts to enable the watchdog. The SW_WATCHDOG option
still causes the sofware watchdog to be enabled even if there is a
hardware watchdog. This does not change the other software-based
watchdog enabled by the --softtimeout option to watchdogd.
Note that the code to reprime the watchdog during kernel core dumps is
no longer conditional on SW_WATCHDOG. I think this was previously a bug.
Reviewed by: imp alfred bjk
MFC after: 1 week
Relnotes: yes
Differential Revision: https://reviews.freebsd.org/D13713
This copies changes from NetBSD into FreeBSD's man page. I compared the
proposed changes against FreeBSD headers and modified them to match.
PR: 214602
Submitted by: fehmi noyan isi <fnoyanisi@yahoo.com>
Introduce new set of loader tunables kern.vt.color.N.rgb, where N is a
number from 0 to 15. The value is either comma-separated list decimal
numbers ranging from 0 to 255 that represent values of red, green, and
blue components respectively (i.e. "128,128,128") or 6-digit hex triplet
commonly used to represent colors in HTML or xterm settings (i.e. #808080)
Each tunable overrides one of the 16 hardcoded palette codes and can be set
in loader.conf(5)
Reviewed by: bcr(docs), jilles, manu, ray
MFC after: 2 weeks
Differential Revision: https://reviews.freebsd.org/D13645
A comment in Makefile.inc1 has long stated that LOCAL_DIRS are built last,
after the base system. Incremental improvements in parallel building over
the years have led to LOCAL_DIRS being built in parallel with base system
directories. This change allows the .WAIT directive to appear in LOCAL_DIRS
and LOCAL_LIB_DIRS lists to give the user some control over parallel
building of local additions.
Differential Revision: https://reviews.freebsd.org/D13622
filesystem larger than about 50-55 MiB.
The description of VM_KMEM_SIZE_SCALE is roughly as hand-wavy as my
understanding of the option, but at least mentioning that it's a factor
and giving an empirical datapoint that works will give folks some idea
of what to tweak if they have problems.
MD_READONLY flag for the md device automatically instantiated during
kernel init for an mdroot filesystem.
Note that there is specifically and by design no tunable or sysctl
control over this feature. Without this option, you already have control
over whether the mdroot fs is writeable using vfs.root.mountfrom.options
from loader(8), the root_rw_mount rcvar, and by using "mount -u[rw] /"
or equivelent on the fly. This option is being added to provide a way
to make the mdroot fs truly immutable before userland code begins running.
Differential Revision: https://reviews.freebsd.org/D13411
Email address has changed, uses consistent name (Matthew, not Matt)
Reported by: Matthew Macy <mmacy@mattmacy.io>
Differential Revision: https://reviews.freebsd.org/D13537
Add atomic_load_<type> and atomic_store_<type>, and explain why they
exist.
Define the synchronizes-with relationship and its effects.
Reorder and revise some of the existing text. For example, more
precisely describe when ordinary accesses are atomic.
Reviewed by: jhb, kib
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D13522
the expected default board_vendor value on MIPS SoCs.
This is required by bwn(4) to differentiate between single-band and
dual-band device variants that otherwise share a common chip ID.
Approved by: adrian (mentor, implicit)
Sponsored by: The FreeBSD Foundation
rc.conf(5) documents the gifconfig_<interface> keyword, which is
no longer implemented. Document the replacement, which works with
cloned_interfaces as well.
Reviewed by: dab
Group Reviwers: manpages
MFC after: 3 days
Differential Revision: https://reviews.freebsd.org/D13130
This change adds an implementation of a sysent for running CloudABI
armv6 and armv7 binaries on FreeBSD/arm64. It is a somewhat literal copy
of the armv6 version, except that it's been patched up to use the proper
registers.
Just like for cloudabi32.ko on FreeBSD/amd64, we make use of a vDSO that
automatically pads system call parameters to 64-bit value. These are
stored in a buffer on the stack, meaning we need to use copyin() and
copyout() unconditionally.
type to any value. This can cause page faults and panics due to accessing
uninitialized fields in the "struct ifnet" which are specific to the network
device type.
MFC after: 1 week
Found by: jau@iki.fi
PR: 223767
Sponsored by: Mellanox Technologies
EMBEDDEDPORTS. [1]
Remove and update stale documentation from release(7) while here.
PR: 206344 [1]
MFC after: 3 days
Sponsored by: The FreeBSD Foundation
Add missing support for specifying I/O control flags during core reset,
and resolve a number of siba(4)-specific reset issues:
- Add missing check for target reject flags in siba_is_hw_suspended().
- Remove incorrect wait on SIBA_TMH_BUSY when modifying any target state
register; this should only be done when waiting for initiated
transactions to clear.
- Add missing wait on SIBA_IM_BY when asserting SIBA_IM_RJ.
- Overwrite any previously set SIBA_TML_REJ flag when bringing the core
out of reset. This fixes a lockup that occured when we brought up a core
(after reboot) that had previously been placed into RESET by siba_bwn(4).
Approved by: adrian (mentor, implicit)
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D13039
This includes a number of copyedits for the inline code documentation
comments, updates to the existing bhnd(4), bhndb(4), bcma(4), and siba(4)
man pages, and new man pages for bhnd_chipc(4), bhnd_pmu(4), bhndb_pci(4),
bhnd(9), and bhnd_erom(9).
Approved by: adrian (mentor)
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D13021
The old description has been inaccurate since at least 243271, if not
before.
Submitted by: will
Reviewed by: kib
MFC after: 3 weeks
Sponsored by: Spectra Logic Corp
Differential Revision: https://reviews.freebsd.org/D13108
xlint is currently a fossil. We have much more useful and alive tools
to do now what xlint did twenty years ago.
I did not cleared some stuff which makes lint operational, in
sys/x86/include and sys/sys, but I might do it as followup. The
x86/include/ucontext.h and _types.h hacks made to please lint was the
main reason for my initial proposal to classify xlint as obsolete and
to remove it.
Also I do not intend to clear sccs ids.
Reviewed by: bapt, brooks, emaste, jhb, pfg
Sponsored by: The FreeBSD Foundation
Differential revision: https://reviews.freebsd.org/D13015
The information here is somewhere between ancient to obsolete.
It refers to a time in the internet's history when manual routing
was still useful, talks about UUCP as if its modern, and refers
to documents which I had trouble tracking down.
It seems unlikely that a manual page in this form would be useful, so
just remove it.
Reviewed By: imp, tsoome, bdrewery(?)
Differential Revision: https://reviews.freebsd.org/D12924
This introduces a facility to EVENTHANDLER(9) for explicitly defining a
reference to an event handler list. This is useful since previously all
invokers of events had to do a locked traversal of the global list of
event handler lists in order to find the appropriate event handler list.
By keeping a pointer to the appropriate list an invoker can avoid this
traversal completely. The pointer is initialized with SYSINIT(9) during
the eventhandler stage. Users registering interest in events do not need
to know if the event is backed by such a list, since the list is added
to the global list of lists. As with lists that are not pre-defined it
is safe to register for the events before the list has been created.
This converts the process_* and thread_* events to using the new
facility, as these are events whose locked traversals end up showing up
significantly in ports build workflows (and presumably other workflows
with many short lived threads/procs). It may be advantageous to convert
other events to using the new facility.
The el_flags field is now unused, but leave it be so that this revision
can be MFC'd.
Reviewed by: bdrewery, markj, mjg
Approved by: rstone (mentor)
In collaboration with: ian
MFC after: 4 weeks
Sponsored by: Dell EMC Isilon
Differential Revision: https://reviews.freebsd.org/D12814
- Fix clear doorbell queue buffer for ADAPTER_TYPE_B
- Fix release memory resource when detach device
- Add support for ARC-1216, 1226 SAS 12Gb controllers
- Declare some functions as static
- Change checking dword read/write for IOP rqbuffer.
Many thanks to Areca for continuing to support FreeBSD.
Submitted by: 黃清隆 <ching2048 areca com tw>
MFC after: 2 weeks
of this kind. Describe how to compile the driver into the kernel
and how to load it as a module.
This is useful for people using the MINIMAL kernel configuration file.
PR: 218610
Submitted by: Harald Schmalzbauer (bugzilla.freebsd@omnilan.de)
Reviewed by: noone (1 month inactivity)
MFC after: 2 weeks
Differential Revision: https://reviews.freebsd.org/D12271
NO_OBJ has a very specific meaning in sub-directories in that no object
directory will be made. If a user wanted to skip the 'make obj' phase then
passing -DNO_OBJ would break all sub-directories from building properly. Using
NO_OBJ internally also causes issue with NO_OBJ handling being added in
share/mk/bsd.init.mk soon.
Sponsored by: Dell EMC Isilon
fine when a lot of different flows to be ciphered/deciphered are involved.
However, when a software crypto driver is used, there are
situations where we could benefit from making crypto(9) multi threaded:
- a single flow is to be ciphered: only one thread is used to cipher it,
- a single ESP flow is to be deciphered: only one thread is used to
decipher it.
The idea here is to call crypto(9) using a new mode (CRYPTO_F_ASYNC) to
dispatch the crypto jobs on multiple threads, if the underlying crypto
driver is working in synchronous mode.
Another flag is added (CRYPTO_F_ASYNC_KEEPORDER) to make crypto(9)
dispatch the crypto jobs in the order they are received (an additional
queue/thread is used), so that the packets are reinjected in the network
using the same order they were posted.
A new sysctl net.inet.ipsec.async_crypto can be used to activate
this new behavior (disabled by default).
Submitted by: Emeric Poupon <emeric.poupon@stormshield.eu>
Reviewed by: ae, jmg, jhb
Differential Revision: https://reviews.freebsd.org/D10680
Sponsored by: Stormshield
This changes the build OBJDIR from the older style of /usr/obj/<srcdir> for
native builds, and /usr/obj/<target>.<target_arch>/<srcdir> for cross builds to
a new simpler format of /usr/obj/<srcdir>/<target>.<target_arch>. This
new format is used regardless of cross or native build. It allows
easier management of multiple source tree object directories.
The UNIFIED_OBJDIR option will be removed and its feature made permanent
for the 12.0 release.
Relnotes: yes (don't note UNIFIED_OBJDIR option since it will be removed)
Prior work: D3711 D874
Reviewed by: gjb, sjg
Discussed at: https://lists.freebsd.org/pipermail/freebsd-arch/2016-May/017805.html
Discussed with: emaste
Sponsored by: Dell EMC Isilon
Differential Revision: https://reviews.freebsd.org/D12840
Some devices (P5040, P4080) have multiple frame managers in their DPAA
subsystems. This was prevented by use of a softc singleton in the DPAA
driver. Since if_dtsec(4) has moved to be a child of fman, it can access
the fman device data via the parent object.
Without this the user has to mess with 'make -f Makefile.inc1 ...' to figure
out where the files are installed in the OBJDIR and then they need to copy them
to where they really wanted them. Using DESTDIR may be problematic after
r325001 as well.
The files will be installed to DESTDIR/NXTP where NXTP defaults to /nxb-bin.
MFC after: 2 weeks
Sponsored by: Dell EMC Isilon
Some BMCs support power cycling the chassis via the chassis control
command 2 subcommand 2 (ipmitool called it 'chassis power cycle'). If
the BMC supports the chassis device, register a shutdown_final handler
that sends the power cycle command if request and waits up to 10s for
it to take effect. To minimize stack strain, we preallocate a ipmi
request in the softc. At the moment, we're verbose about what we're
doing.
Sponsored by: Netflix
When using a kernel built with the GZIO config option, dumpon -z can be
used to configure gzip compression using the in-kernel copy of zlib.
This is useful on systems with large amounts of RAM, which require a
correspondingly large dump device. Recovery of compressed dumps is also
faster since fewer bytes need to be copied from the dump device.
Because we have no way of knowing the final size of a compressed dump
until it is written, the kernel will always attempt to dump when
compression is configured, regardless of the dump device size. If the
dump is aborted because we run out of space, an error is reported on
the console.
savecore(8) is modified to handle compressed dumps and save them to
vmcore.<index>.gz, as it does when given the -z option.
A new rc.conf variable, dumpon_flags, is added. Its value is added to
the boot-time dumpon(8) invocation that occurs when a dump device is
configured in rc.conf.
Reviewed by: cem (earlier version)
Discussed with: def, rgrimes
Relnotes: yes
Sponsored by: Dell EMC Isilon
Differential Revision: https://reviews.freebsd.org/D11723
Mention per-location total order, out of thin air, and torn writes
guarantees. Mention C11 standard' memory model and one most important
FreeBSD additional requirement, that is aligned ordinary loads and
stores are atomic on processors.
The text is introductional and informal. Reference the C11 and
C++1{1,4,7} standards for authorative description.
In collaboration with: alc
Sponsored by: The FreeBSD Foundation (kib)
MFC after: 1 week
1. Add a reference to a good 3rd party list of compatible cables, but
provide suggestions for 'known good' vendors.
2. Change IP-based USB host-host example to a modern Ethernet one which
works 'out of box' with current Linux systems.
3. Explain that USB 3.0 is host-host, even though point-to-point soft
Ethernet can be achieved.
MFC after: 3 weeks
files. This is a follow up commit to r324721, which added sysrc(8) to
the SEE ALSO list.
Submitted by: Kurt Jaeger (lists at opsec.eu)
MFC after: 1 week
mbpool existed to support NICs with memory interfaces and all remaining
comsumers were removed earlier this year with NATM.
Reviewed by: jhb
Sponsored by: DARPA, AFRL
Differential Revision: https://reviews.freebsd.org/D10513
Previously before you could call unrhdr_delete you needed to
individually free every allocated unit. It is useful to be able to tear
down the unr without having to go through this process, as it is
significantly faster than freeing the individual units.
Reviewed by: cem, lidl
Approved by: rstone (mentor)
Sponsored by: Dell EMC Isilon
Differential Revision: https://reviews.freebsd.org/D12591
All of these arguments are stored in m_ext, so there is no reason
to pass them in the argument list. Not all functions need the second
argument, some don't even need the first one. The second argument
lives in next cache line, so not dereferencing it is a performance
gain. This was discovered in sendfile(2), which will be covered by
next commits.
The second goal of this commit is to bring even more flexibility
to m_ext mbufs, allowing to create more fields in m_ext, opaque to
the generic mbuf code, and potentially set and dereferenced by
subsystems.
Reviewed by: gallatin, kbowling
Differential Revision: https://reviews.freebsd.org/D12615
When the EVENTHANDLER(9) subsystem was created, it was a documented feature
that an eventhandler callback function could safely deregister itself. In
r200652 that feature was inadvertantly broken by adding drain-wait logic to
eventhandler_deregister(), so that it would be safe to unload a module upon
return from deregistering its event handlers.
There are now 145 callers of EVENTHANDLER_DEREGISTER(), and it's likely many
of them are depending on the drain-wait logic that has been in place for 8
years. So instead of creating a separate eventhandler_drain() and adding it
to some or all of those 145 call sites, this creates a separate
eventhandler_drain_nowait() function for the specific purpose of
deregistering a callback from within the running callback.
Differential Revision: https://reviews.freebsd.org/D12561
This file shouldn't be modified manually but well, I did it in my previous
commit. So go down further the rabbit hole so as to at least keep some
consistency.
Reported by: bapt
If they are still needed, you can find them in the net/bsdrcmds port.
This was proposed June, 20th and approved by various committers [1].
They have been marked as deprecated on CURRENT in r320644 [2] on July, 4th.
Both stable/11 and release/11.1 contain the deprecation notice (thanks to
allanjude@).
Note that ruptime(1)/rwho(1)/rwhod(8) were initially thought to be part of
rcmds but this was a mistake and those are therefore NOT removed.
[1] https://lists.freebsd.org/pipermail/freebsd-arch/2017-June/018239.html
[2] https://svnweb.freebsd.org/base?view=revision&revision=320644
Reviewed by: bapt, brooks
Differential Revision: https://reviews.freebsd.org/D12573
It was supposed to provide a recovery mechanism against bugs in procfs's
long deprecated tracing capabilities.
Remove the tool as a prerequisite to axing the kernel side.
The tracing facility to use is ptrace(2).
MFC after: 2 weeks
Some x86 class CPUs have accelerated intrinsics for SHA1 and SHA256.
Provide this functionality on CPUs that support it.
This implements CRYPTO_SHA1, CRYPTO_SHA1_HMAC, and CRYPTO_SHA2_256_HMAC.
Correctness: The cryptotest.py suite in tests/sys/opencrypto has been
enhanced to verify SHA1 and SHA256 HMAC using standard NIST test vectors.
The test passes on this driver. Additionally, jhb's cryptocheck tool has
been used to compare various random inputs against OpenSSL. This test also
passes.
Rough performance averages on AMD Ryzen 1950X (4kB buffer):
aesni: SHA1: ~8300 Mb/s SHA256: ~8000 Mb/s
cryptosoft: ~1800 Mb/s SHA256: ~1800 Mb/s
So ~4.4-4.6x speedup depending on algorithm choice. This is consistent with
the results the Linux folks saw for 4kB buffers.
The driver borrows SHA update code from sys/crypto sha1 and sha256. The
intrinsic step function comes from Intel under a 3-clause BSDL.[0] The
intel_sha_extensions_sha<foo>_intrinsic.c files were renamed and lightly
modified (added const, resolved a warning or two; included the sha_sse
header to declare the functions).
[0]: https://software.intel.com/en-us/articles/intel-sha-extensions-implementations
Reviewed by: jhb
Sponsored by: Dell EMC Isilon
Differential Revision: https://reviews.freebsd.org/D12452
This requests that the cipher be performed before rather than after
the HMAC when both are specified for a single operation.
Reviewed by: cem
Sponsored by: Chelsio Communications
Differential Revision: https://reviews.freebsd.org/D11757
in favor of just rendering the manpage instead of relying on pre-formatted
catpages. Note, this does not impede the ability to use existing catpages,
it just removes the utility to generate them.
Reviewed by: imp, allanjude
Approved by: emaste (mentor)
Differential Revision: https://reviews.freebsd.org/D12317
The sensor value is formatted similarly to previous models (same
bitfield sizes, same units), but must be read off of the internal
System Management Network (SMN) from the System Management Unit (SMU)
co-processor.
PR: 218264
Reported and tested by: Nils Beyer <nbe AT renzel.net>
Reviewed by: avg (no +1), mjoras, truckman
Sponsored by: Dell EMC Isilon
Differential Revision: https://reviews.freebsd.org/D12217
AMD Family 17h CPUs have an internal network used to communicate between
the host CPU and the PSP and SMU coprocessors. It exposes a simple
32-bit register space.
Reviewed by: avg (no +1), mjoras, truckman
Sponsored by: Dell EMC Isilon
Differential Revision: https://reviews.freebsd.org/D12217
This driver supports both NTB-to-NTB and NTB-to-Root Port modes (though
the second with predictable complications on hot-plug and reboot events).
I tested it with PEX 8717 and PEX 8733 chips, but expect it should work
with many other compatible ones too. It supports up to two NT bridges
per chip, each of which can have up to 2 64-bit or 4 32-bit memory windows,
6 or 12 scratchpad registers and 16 doorbells. There are also 4 DMA engines
in those chips, but they are not yet supported.
While there, rename Intel NTB driver from generic ntb_hw(4) to more specific
ntb_hw_intel(4), so now it is on par with this new ntb_hw_plx(4) driver and
alike to Linux naming.
MFC after: 2 weeks
Sponsored by: iXsystems, Inc.
A follow-up to r322836.
Warnings for the unused declaration were breaking some second tier
architectures, but did not show up in Clang on x86.
Reported by: markj (ddb.4), emaste (declaration)
Sponsored by: Dell EMC Isilon
Remote DMA over Converged Ethernet, RoCE, for the ConnectX-4 series of
PCI express network cards.
There is currently no user-space support and this driver only supports
kernel side non-routable RoCE V1. The krping kernel module can be used
to test this driver. Full user-space support including RoCE V2 will be
added as part of the ongoing upgrade to ibcore from Linux 4.9. Otherwise
this driver is feature equivalent to mlx4ib(4). The mlx5ib(4) kernel
module will only be built when WITH_OFED=YES is specified.
MFC after: 2 weeks
Sponsored by: Mellanox Technologies
during drain operations. When an sbuf is configured to use this feature by way
of the SBUF_DRAINTOEOR sbuf_new() flag, top-level sections started with
sbuf_start_section() create a record boundary marker that is used to avoid
flushing partial records.
Reviewed by: cem,imp,wblock
MFC after: 2 weeks
Sponsored by: Netflix, Inc.
Differential Revision: https://reviews.freebsd.org/D8536
it automatically after it runs.
The config_intrhook mechanism allows a driver to stall the boot process
until device(s) required for booting are available, by not allowing system
inits to proceed until all intrhook functions have been unregistered.
Virtually all existing code simply unregisters from within the hook function
when it gets called.
This new function makes that common usage more convenient. Instead of
allocating and filling in a struct, passing it to a function that might (in
theory) fail, and checking the return code, now a driver can simply call
this cannot-fail routine, passing just the intrhook function and its arg.
Differential Revision: https://reviews.freebsd.org/D11963
geom_bsd, geom_mbr and geom_sunlabel have been obsolete since Marcel
Moolenaar's geom_part was in FreeBSD 7. They haven't been in GENERIC
since FreeBSD 8. Add warning when used.
geom_vol_ffs has been obsolete since ufs support to geom_label was
committed in FreeBSD 5. It hasn't been in GENERIC since FreeBSD 5.
Add warning when used.
geom_fox has been obsolete since gmultipath was committed in FreeBSD 7.
(no warning added, since this is a very obscure class).
These will all be removed in FreeBSD 12.
MFC After: 3 days
Differential Revision: https://reviews.freebsd.org/D11935
Note: Classes will be removed after MFC
New flag 0x4 can be configured in net.enc.[in|out].ipsec_bpf_mask.
When it is set, if_enc(4) additionally captures a packet via BPF after
invoking pfil hook. This may be useful for debugging.
MFC after: 2 weeks
Sponsored by: Yandex LLC
Differential Revision: https://reviews.freebsd.org/D11804
Implement disk_add_alias to allow aliases to be added to disks. All
disk have a primary name (say "foo") can also have secondary names
(say "bar") such that all instances of "foo" also have a "bar"
alias. So if you have foo0, foo0p1, foo1, foo1s1 and foo1s1a nodes
created by the foo driver and gpart, device nodes bar0, bar0p1, bar1,
bar1s1 and bar1s1a will appear as symlinks back to the original nodes.
This generalizes to multiple aliases. However, since the unit number
follows the primary name, multiple device drivers can't create the
same aliases unless those drives coorinate the unit number space (eg
you couldn't add an alias 'disk' to both 'da' and 'ada' because it's
possible to have da0 and ada0, because 'disk0' is ambiguous).
Differential Revision: https://reviews.freebsd.org/D11873
o Replace __riscv64 with (__riscv && __riscv_xlen == 64)
This is required to support new GCC 7.1 compiler.
This is compatible with current GCC 6.1 compiler.
RISC-V is extensible ISA and the idea here is to have built-in define
per each extension, so together with __riscv we will have some subset
of these as well (depending on -march string passed to compiler):
__riscv_compressed
__riscv_atomic
__riscv_mul
__riscv_div
__riscv_muldiv
__riscv_fdiv
__riscv_fsqrt
__riscv_float_abi_soft
__riscv_float_abi_single
__riscv_float_abi_double
__riscv_cmodel_medlow
__riscv_cmodel_medany
__riscv_cmodel_pic
__riscv_xlen
Reviewed by: ngie
Sponsored by: DARPA, AFRL
Differential Revision: https://reviews.freebsd.org/D11901
Remove some statements which are no longer correct after ino64, and
clarify other.
The rewording is not in fact specific to ino64 and improvements are
useful on the stable branches.
Noted and reviewed by: bde
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
- Store the symbol table contents in an anonymous swap-backed object. Have
mmap(/dev/ksyms) map that object, and stop mapping the symbol table into
the calling process in ksyms_open(). Previously we would cache a pointer
to the pmap of the opening process, and mmap(/dev/ksyms) would create a
mapping using the physical address found by a pmap lookup at the initial
mapping address. However, this assumes that the cached pmap is valid,
which may not be the case. [1]
- Remove the ksyms ioctl interface. It appears to have been added to work
around a limitation in libelf that no longer exists; see r321842.
Moreover, the interface is difficult to support and isn't present in
illumos. Since ksyms was added specifically to support lockstat(1), it
is expected that this removal won't have any real impact.
- Simplify ksyms_read() to avoid unnecessary copying.
- Don't call the device handle destructor if we fail to capture a snapshot
of the kernel's symbol table. devfs will do that for us.
Reported by: Ilja van Sprundel <ivansprundel@ioactive.com> [1]
Reviewed by: kib (previous revision)
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D11789
Linux specific things to the native fdescfs file system.
Unlike FreeBSD, the Linux fdescfs is a directory containing a symbolic
links to the actual files, which the process has open.
A readlink(2) call on this file returns a full path in case of regular file
or a string in a special format (type:[inode], anon_inode:<file-type>, etc..).
As well as in a FreeBSD, opening the file in the Linux fdescfs directory is
equivalent to duplicating the corresponding file descriptor.
Here we have mutually exclusive requirements:
- in case of readlink(2) call fdescfs lookup() method should return VLNK
vnode otherwise our kern_readlink() fail with EINVAL error;
- in the other calls fdescfs lookup() method should return non VLNK vnode.
For what new vnode v_flag VV_READLINK was added, which is set if fdescfs has beed
mounted with linrdlnk option an modified kern_readlinkat() to properly handle it.
For now For Linux ABI compatibility mount fdescfs volume with linrdlnk option:
mount -t fdescfs -o linrdlnk null /compat/linux/dev/fd
Reviewed by: kib@
MFC after: 1 week
Relnotes: yes
over the scheduling precision than 'ticks' can offer, and because sometimes
you're already working with sbintime_t units and it's dumb to convert them
to ticks just so they can get converted back to sbintime_t under the hood.
- Remove 'if_rtwn_load="YES"' line from loader.conf; the module was
renamed in r319733 + it will be loaded automatically as a dependency.
- Move new sentence to new line.
- Add short description for dev.rtwn.%d.rx_buf_size tunable.
If ipfw_netflow_fib, the ipfw rule will only match packets in that FIB.
While here correct some value in rc.conf(5) to be int and not str.
Sponsored by: Gandi.net
The benefit of BIT_FLS() is that ffsl() can be implemented with a
count leading zeros instruction which is more widespread available.
Submitted by: Sebastian Huber <sebastian.huber@embedded-brains.de>
MFC after: 1 week
- Address most of the post-commit comments on D11128.[1]
- Reference the man pages for the lock types supported by the provider.
- Add a BUGS section.
- Eliminate some redundancy by describing similar probes in the same
paragraph.
- Fix several inaccuracies, particularly in the probe argument
descriptions.
Submitted by: wblock [1]
MFC after: 2 weeks
Differential Revision: https://reviews.freebsd.org/D11293
Instead of using GID_FT SNS request to get list of registered FCP ports,
use GID_PT to get list of all Nx_Ports, and then use GFF_ID and/or GFT_ID
requests to find whether they are FCP and target capable.
The problem with old approach is that GID_FT does not report ports without
FC-4 type registered. In particular it was impossible to boot OS from
FreeBSD FC target using QLogic FC BIOS, since one does not register FC-4
type even on new cards and so ignored by old code as incompatible.
As a side bonus this allows initiator to skip pointless logins to other
initiators by fetching that information from SNS instead.
In case some switches do not implement GFF_ID/GFT_ID correctly, add sysctls
to disable that functionality. I handled broken GFF_ID of my Brocade 200E,
but there may be other switches with different bugs.
Linux also uses GID_PT, but GFF_ID is disabled by default there, and GFT_ID
is not supported.
Sponsored by: iXsystems, Inc.
AKA Make time_t 64 bits on powerpc(32).
PowerPC currently (until now) was one of two architectures with a 32-bit time_t
on 32-bit archs (the other being i386). This is an ABI breakage, so all ports,
and all local binaries, *must* be recompiled.
Tested by: andreast, others
MFC after: Never
Relnotes: Yes
Add a make.conf DTC variable that control which DTC (Device Tree Compiler)
to use.
Reviewed by: bdrewery, imp
Differential Revision: https://reviews.freebsd.org/D9577
Zap trailing white and double spaces
Remove extra coma which is not required.
Bump date.
Reviewed by: gnn
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D11142
stack modules.
It adds support for mangling symbols exported by a module by prepending
a string to them. (This avoids overlapping symbols in the kernel linker.)
It allows the use of a macro as the module name in the DECLARE_MACRO()
and MACRO_VERSION() macros.
It allows the code to register stack aliases (e.g. both a generic name
["default"] and version-specific name ["default_10_3p1"]).
With these changes, it is trivial to compile TCP stack modules with
the name defined in the Makefile and to load multiple versions of the
same stack simultaneously. This functionality can be used to enable
side-by-side testing of an old and new version of the same TCP stack.
It also could support upgrading the TCP stack without a reboot.
Reviewed by: gnn, sjg (makefiles only)
Sponsored by: Netflix
Differential Revision: https://reviews.freebsd.org/D11086
Update the documentation to catch up with r273174, which renamed
getenv -> kern_getenv
setenv -> kern_setenv
unsetenv -> kern_unsetenv
Leave the old links in place to support finger memory.
MFC after: 3 days
Sponsored by: Dell EMC
bhyve was recently sandboxed with capsicum, and needs to be able to
control the CPU sets of its vcpu threads
Reviewed by: emaste, oshogbo, rwatson
MFC after: 2 weeks
Sponsored by: ScaleEngine Inc.
Differential Revision: https://reviews.freebsd.org/D10170
Extend the ino_t, dev_t, nlink_t types to 64-bit ints. Modify
struct dirent layout to add d_off, increase the size of d_fileno
to 64-bits, increase the size of d_namlen to 16-bits, and change
the required alignment. Increase struct statfs f_mntfromname[] and
f_mntonname[] array length MNAMELEN to 1024.
ABI breakage is mitigated by providing compatibility using versioned
symbols, ingenious use of the existing padding in structures, and
by employing other tricks. Unfortunately, not everything can be
fixed, especially outside the base system. For instance, third-party
APIs which pass struct stat around are broken in backward and
forward incompatible ways.
Kinfo sysctl MIBs ABI is changed in backward-compatible way, but
there is no general mechanism to handle other sysctl MIBS which
return structures where the layout has changed. It was considered
that the breakage is either in the management interfaces, where we
usually allow ABI slip, or is not important.
Struct xvnode changed layout, no compat shims are provided.
For struct xtty, dev_t tty device member was reduced to uint32_t.
It was decided that keeping ABI compat in this case is more useful
than reporting 64-bit dev_t, for the sake of pstat.
Update note: strictly follow the instructions in UPDATING. Build
and install the new kernel with COMPAT_FREEBSD11 option enabled,
then reboot, and only then install new world.
Credits: The 64-bit inode project, also known as ino64, started life
many years ago as a project by Gleb Kurtsou (gleb). Kirk McKusick
(mckusick) then picked up and updated the patch, and acted as a
flag-waver. Feedback, suggestions, and discussions were carried
by Ed Maste (emaste), John Baldwin (jhb), Jilles Tjoelker (jilles),
and Rick Macklem (rmacklem). Kris Moore (kris) performed an initial
ports investigation followed by an exp-run by Antoine Brodin (antoine).
Essential and all-embracing testing was done by Peter Holm (pho).
The heavy lifting of coordinating all these efforts and bringing the
project to completion were done by Konstantin Belousov (kib).
Sponsored by: The FreeBSD Foundation (emaste, kib)
Differential revision: https://reviews.freebsd.org/D10439
ENA is a networking interface designed to make good use of modern CPU
features and system architectures.
The ENA device exposes a lightweight management interface with a
minimal set of memory mapped registers and extendable command set
through an Admin Queue.
The driver supports a range of ENA devices, is link-speed independent
(i.e., the same driver is used for 10GbE, 25GbE, 40GbE, etc.), and has
a negotiated and extendable feature set.
Some ENA devices support SR-IOV. This driver is used for both the
SR-IOV Physical Function (PF) and Virtual Function (VF) devices.
ENA devices enable high speed and low overhead network traffic
processing by providing multiple Tx/Rx queue pairs (the maximum number
is advertised by the device via the Admin Queue), a dedicated MSI-X
interrupt vector per Tx/Rx queue pair, and CPU cacheline optimized
data placement.
The ENA driver supports industry standard TCP/IP offload features such
as checksum offload and TCP transmit segmentation offload (TSO).
Receive-side scaling (RSS) is supported for multi-core scaling.
The ENA driver and its corresponding devices implement health
monitoring mechanisms such as watchdog, enabling the device and driver
to recover in a manner transparent to the application, as well as
debug logs.
Some of the ENA devices support a working mode called Low-latency
Queue (LLQ), which saves several more microseconds. This feature will
be implemented for driver in future releases.
Submitted by: Michal Krawczyk <mk@semihalf.com>
Jakub Palider <jpa@semihalf.com>
Jan Medala <jan@semihalf.com>
Obtained from: Semihalf
Sponsored by: Amazon.com Inc.
Differential revision: https://reviews.freebsd.org/D10427
The ccr(4) driver supports use of the crypto accelerator engine on
Chelsio T6 NICs in "lookaside" mode via the opencrypto framework.
Currently, the driver supports AES-CBC, AES-CTR, AES-GCM, and AES-XTS
cipher algorithms as well as the SHA1-HMAC, SHA2-256-HMAC, SHA2-384-HMAC,
and SHA2-512-HMAC authentication algorithms. The driver also supports
chaining one of AES-CBC, AES-CTR, or AES-XTS with an authentication
algorithm for encrypt-then-authenticate operations.
Note that this driver is still under active development and testing and
may not yet be ready for production use. It does pass the tests in
tests/sys/opencrypto with the exception that the AES-GCM implementation
in the driver does not yet support requests with a zero byte payload.
To use this driver currently, the "uwire" configuration must be used
along with explicitly enabling support for lookaside crypto capabilities
in the cxgbe(4) driver. These can be done by setting the following
tunables before loading the cxgbe(4) driver:
hw.cxgbe.config_file=uwire
hw.cxgbe.cryptocaps_allowed=-1
MFC after: 1 month
Relnotes: yes
Sponsored by: Chelsio Communications
Differential Revision: https://reviews.freebsd.org/D10763
This includes NVMe device support and adds support for the following adapters:
SAS 3408
SAS 3416
SAS 3508
SAS 3516
SAS 3616
SAS 3708
SAS 3716
Reviewed by: ken, scottl, asomers, mav
Approved by: ken, scottl, mav
MFC after: 2 weeks
Relnotes: yes
Differential Revision: https://reviews.freebsd.org/D10095
This function permits a range of one scatter/gather list to be appended to
another sglist. This can be used to construct a scatter/gather list that
reorders or duplicates ranges from one or more existing scatter/gather
lists.
Sponsored by: Chelsio Communications
to the example, change the architectures to something more common,
and improve description of defaults for TARGET.
Reviewed by: bdrewery, ngie, imp (older revisions)
MFC after: 2 weeks
Differential Revision: https://reviews.freebsd.org/D10654
This allows for building the world against the already-created
host/sysroot environment. It is not overly useful outside of cases of
large-impact changes such as a testing a new compiler. It will
allow quickly getting back to an error in the target-phases of the
build where a new compiler is being used.
Sponsored by: Dell EMC Isilon
Attempt to catch up to the KPI changes from r292373, and perform
some other tidying while in the area.
Reviewed by: kib
Differential Revision: https://reviews.freebsd.org/D10579
This will help application developers simulate end of tape conditions.
To inject an error in sa0:
sysctl kern.cam.sa.0.inject_eom=1
This will return the next read or write request queued with 0 bytes
written. Any subsequent writes or reads will go along as usual.
This will also cause the early warning position flag to get set
for the next position query. So, 'mt status' will show the BPEW
(Beyond Programmable Early Warning) flag on the first query after
an error injection. After that, the position flags will be as they
are in the underlying tape drive.
Also, update the sa(4) man page to describe tape parameters,
which can be set via 'mt param'.
sys/cam/scsi/scsi_sa.c:
In saregister(), create the inject_eom sysctl variable.
In sastart(), check to see whether inject_eom is set. If
so, return the read or write with 0 bytes written to
indicate EOM. Set the set_pews_status flag so that we
fake PEWS status in the next position call for reads, and the
next 3 calls for writes. This allows the user to see the BPEW
flag one time via 'mt status'.
In sagetpos(), check the set_pews_status flag and fake
PEWS status and decrement the counter if it is set.
share/man/man4/sa.4:
Document the inject_eom sysctl variable.
Document all of the parameters currently supported via
'mt param'.
usr.bin/mt/mt.1:
Point the user to the sa(4) man page for more details on
supported parameters.
MFC after: 3 days
Sponsored by: Spectra Logic
Start with some words about linear address space and its layout, then
explain pointers models and ABIs, providing explanation to the
structure of the tables.
Reviewed by: emaste, imp
'Future-proof' cheri wording by: brooks
Sponsored by: The FreeBSD Foundation
MFC after: 2 weeks
Differential revision: https://reviews.freebsd.org/D10596
After FreeBSD SVN revision 236814, the pass(4) driver changed from
only doing error recovery when the CAM_PASS_ERR_RECOVER flag was
set on a CCB to sometimes doing error recovery if the passed in
retry count was non-zero.
Error recovery would happen if two conditions were met:
1. The error recovery action was simply a retry. (Which is most
cases.)
2. The retry_count is non-zero. (Which happened a lot because of
cut-and-pasted code.)
This explains a bug I noticed in with camcontrol:
# camcontrol tur da34 -v
Unit is ready
# camcontrol reset da34
Reset of 1:172:0 was successful
At this point, there should be a Unit Attention:
# camcontrol tur da34 -v
Unit is ready
No Unit Attention.
Try it again:
# camcontrol reset da34
Reset of 1:172:0 was successful
Now set the retry_count to 0 for the TUR:
# camcontrol tur da34 -v -C 0
Unit is not ready
(pass42:mps1:0:172:0): TEST UNIT READY. CDB: 00 00 00 00 00 00
(pass42:mps1:0:172:0): CAM status: SCSI Status Error
(pass42:mps1:0:172:0): SCSI status: Check Condition
(pass42:mps1:0:172:0): SCSI sense: UNIT ATTENTION asc:29,2 (SCSI bus reset occurred)
(pass42:mps1:0:172:0): Field Replaceable Unit: 2
There is the unit attention. camcontrol(8) has a default
retry_count of 1, in case someone sets the -E flag without
setting -C.
The CAM_PASS_ERR_RECOVER behavior was only broken with the
CAMIOCOMMAND ioctl, which is the synchronous pass(4) API. It has
worked as intended (error recovery is only done when the flag
is set) in the asynchronous API (CAMIOQUEUE ioctl).
sys/cam/scsi/scsi_pass.c:
In passsendccb(), when calling cam_periph_runccb(), only
specify the error routine when CAM_PASS_ERR_RECOVER is set.
share/man/man4/pass.4:
Document that CAM_PASS_ERR_RECOVER is needed to enable
error recovery.
Reported by: Terry Kennedy <TERRY@glaver.org>
PR: kern/218572
MFC after: 1 week
Sponsored by: Spectra Logic
