that can be extended, but also ensure compile-time type checking. Refactor
common code out of arch-specific implementations. Move the mpr and mps
drivers to this new API. The template type remains visible to the consumer
so that it can be allocated on the stack, but should be considered opaque.
To make it easier to work with this in the future, convert to c99
designated initializer syntax.
Tested on powerpc, powerpc64, and powerpc64le. No functional change.
Sponsored by: Tag1 Consulting, Inc.
The intention of the bus_be naming was for those to be the no-endian-swapping
and for the bus_le to be endian-swapping in all the functions.
This naming breaks down when we're actually are running in LE and need to
use the opposite sense.
As such, rename bs_be_* to native_bs_* and rename bs_le_* to swapped_bs_*.
No functional change.
Sponsored by: Tag1 Consulting, Inc.
Swap the BE and LE bus_space tags when on LE, and adjust the nexus tag
to match.
This is prep for a a followup that makes the powerpc bus_space macros easier
to maintain in the future.
Sponsored by: Tag1 Consulting, Inc.
Implement pmap_mincore() for moea64.
This will need some slight tweaks when large page support in HPT lands.
Submitted by: Fernando Eckhardt Valle <fernando.valle@eldorado.org.br>
Reviewed by: bdragon
Differential Revision: https://reviews.freebsd.org/D26314
* Add LOAD_LR_NIA define. This is preferred to "bl 1f; 1:" because it
doesn't pollute the branch predictor.
* Add magic sequence to return the CPU to the correct endianness after
jumping to cross-endian code, similar to the sequence from Linux.
Sponsored by: Tag1 Consulting, Inc.
There were multiple bugs in the OPAL RTC code which had never been
discovered, as the default configuration of OPAL machines is to
have the BMC / FSP control the RTC.
* Fix calling convention for setting the time -- the variables are passed
directly in CPU registers, not via memory.
* Fix bug in the bcd encoding routines. (from jhibbits)
Tested on POWER9 Talos II (BE) and POWER9 Blackbird (LE).
Reviewed by: jhibbits (in irc)
Sponsored by: Tag1 Consulting, Inc.
When emulating a single thread system for testing reasons, mp_maxid can
be 0. This trips up our math for calculating the order.
Account for this to fix xive attachment when emulating a single-thread
core on qemu powernv (a configuration that doesn't exist in the real world.)
Sponsored by: Tag1 Consulting, Inc.
When doing a build for a modern CPUTYPE, llvm will throw errors if obsolete
instructions are used, even if they will never run due to runtime checks.
Hiding the dssall instruction from the assembler fixes kernel build when
overriding CPUTYPE, without having any effect on the generated binary.
This has been in my local tree for over a year and is well tested across
a variety of machines.
Sponsored by: Tag1 Consulting, Inc.
When enabling an interrupt, assert that we do in fact have a root PIC.
This would have saved me some debugging effort.
Sponsored by: Tag1 Consulting, Inc.
Implement the remaining pieces needed to allow userland timestamp reading.
Rewritten based on an intial essay into the problem by Justin Hibbits.
(Copyright changed to my own on his request.)
Tested on ppc64 (POWER9 Talos II), powerpcspe (e500v2 RB800), and
powerpc (g4 PowerBook).
Reviewed by: jhibbits (in irc)
Sponsored by: Tag1 Consulting, Inc.
Differential Revision: https://reviews.freebsd.org/D26347
In order to enable VDSO timekeeping, it is necessary that there be exactly
one primary FreeBSD sysvec for each of the host and (optionally) compat32.
So, switch ELFv1 to being a secondary sysvec of ELFv2, so it does not get
double-allocated in the shared page.
Since secondary sysvecs use the same sigcode allocation as the primary,
define both to use the main sigcode64, and adjust the sv_sigcode_base on
ELFv2 after initialization to point to the correct offset.
This has the desirable side effect of avoiding having a separate copy of
the signal trampoline in the shared page. Our sigcode64 was already written
to take advantage of trampoline sharing, it was just not being allocated
that way until now.
Submitted by: jhibbits
Sponsored by: Tag1 Consulting, Inc.
Currently we use a single bit to indicate whether the virtual page is
part of a superpage. To support a forthcoming implementation of
non-transparent 1GB superpages, it is useful to provide more detailed
information about large page sizes.
The change converts MINCORE_SUPER into a mask for MINCORE_PSIND(psind)
values, indicating a mapping of size psind, where psind is an index into
the pagesizes array returned by getpagesizes(3), which in turn comes
from the hw.pagesizes sysctl. MINCORE_PSIND(1) is equal to the old
value of MINCORE_SUPER.
For now, two bits are used to record the page size, permitting values
of MAXPAGESIZES up to 4.
Reviewed by: alc, kib
Sponsored by: Juniper Networks, Inc.
Sponsored by: Klara, Inc.
Differential Revision: https://reviews.freebsd.org/D26238
This allows privileged userspace processes to find information about the
physical page backing a given mapping. It is useful in applications
such as DPDK which perform some of their own memory management.
Reviewed by: kib, jhb (previous version)
MFC after: 2 weeks
Sponsored by: Juniper Networks, Inc.
Sponsored by: Klara Inc.
Differential Revision: https://reviews.freebsd.org/D26237
PMCLOG macros were always using 32-bit addresses, even on PPC64.
This resulted in truncated addresses in logs, when running on 64-bit PPC
machines.
Sponsored by: Eldorado Research Institute (eldorado.org.br)
Differential Revision: https://reviews.freebsd.org/D26112
Calling pmc_hook inside a critical section may result in a panic.
This happens when the user callchain is fetched, because it uses
pmap_map_user_ptr, that tries to get the (sleepable) pmap lock when the
needed vsid is not found.
Judging by the implementation in other platforms, intr_irq_handler in
kern/subr_intr.c and what pmc_hook do, it seems safe to move pmc_hook
outside the critical section.
Sponsored by: Eldorado Research Institute (eldorado.org.br)
Differential Revision: https://reviews.freebsd.org/D26111
When SMP support for powerpc was added in r178628, the last callers of this
function were removed. All code that needs to manipulate the task priority
just does it directly instead.
Noticed while reading through the lint logs.
Sponsored by: Tag1 Consulting, Inc.
Assume ELF images without OSREL use the new auxv format.
This is specially important for rtld, that is not tagged. Using
direct exec mode with new (ELFv2) binaries that expect the new auxv
format would result in crashes otherwise.
Unfortunately, this may break direct exec'ing old binaries,
but it seems better to correctly support new binaries by default,
considering the transition to ELFv2 happened quite some time
ago. If needed, a sysctl may be added to allow old auxv format to
be used when OSREL is not found.
Reviewed by: bdragon
Sponsored by: Eldorado Research Institute (eldorado.org.br)
Differential Revision: https://reviews.freebsd.org/D25651
Currently, we parse notes for the values of ELF FreeBSD feature flags
and osrel. Knowing these values, or knowing that image does not carry
the note if pointers are NULL, is useful to decide which ABI variant
(brand) we want to activate for the image.
Right now this is only a plumbing change
Tested by: pho
Sponsored by: The FreeBSD Foundation
Differential revision: https://reviews.freebsd.org/D25273
After spending a lot of time trying to track down what was going on, I have
isolated the "black screen" failures when using boot1 to boot a G4 machine.
It turns out we were replacing the traps before installing the temporary
BAT entry for the bottom of physical memory. That meant that until the MMU
was bootstrapped, the cached translations were the only thing keeping us
from losing.
Throwing boot1 into the mix was affecting execution flow enough to cause us
to hit an uncached page and crash.
Fix this by properly setting up the initial BAT entry at the same time we
are replacing the OpenFirmware traps, so we can continue executing in
segment 0 until the rest of the DMAP has been set up.
A second thing discovered while researching this is that we were entering a
BAT region for segment 16. It turns out this range was a) considered part
of KVA, and b) has firmware mappings with varying attributes.
If we ever accessed an unmapped page in segment 16, it would cause a BAT
entry to be installed for the whole segment, which would bypass the
existing mappings until it was flushed out again.
Instead, translate the OFW memory attributes into VM memory attributes and
install the ranges into the kernel address space properly.
Reviewed by: adalava
MFC after: 3 weeks
Sponsored by: Tag1 Consulting, Inc.
Differential Revision: https://reviews.freebsd.org/D25547
This fixes spurious "XIVE[ IC 00 ] ISN 1 lead to invalid IVE !" messages
generated by OPAL when running with the debug level cranked up.
Discussed with jhibbits.
Sponsored by: Tag1 Consulting, Inc.
Being able to use tmpfs without kernel modules is very useful when building
small MFS_ROOT kernels without a real file system.
Including TMPFS also matches arm/GENERIC and the MIPS std.MALTA configs.
Compiling TMPFS only adds 4 .c files so this should not make much of a
difference to NO_MODULES build times (as we do for our minimal RISC-V
images).
Reviewed By: br (earlier version for riscv), brooks, emaste
Differential Revision: https://reviews.freebsd.org/D25317
Subsequent to r240317, kmem_free() was replaced with kva_free() (r254025).
kva_free() releases the KVA allocation for the mapped region, but no longer
clears the pmap (pagetable) entries.
An affected pmap_unmapdev operation would leave the still-pmap'd VA space
free for allocation by other KVA consumers. However, this bug easily
avoided notice for ~7 years because most devices (1) never call
pmap_unmapdev and (2) on amd64, mostly fit within the DMAP and do not need
KVA allocations. Other affected arch are less popular: i386, MIPS, and
PowerPC. Arm64, arm32, and riscv are not affected.
Reported by: Don Morris <dgmorris AT earthlink.net>
Submitted by: Don Morris (amd64 part)
Reviewed by: kib, markj, Don (!amd64 parts)
MFC after: I don't intend to, but you might want to
Sponsored by: Dell Isilon
Differential Revision: https://reviews.freebsd.org/D25689
This removes SCTP from in-tree kernel configuration files. Now, SCTP
can be enabled by simply loading the module, as discussed on
freebsd-net@.
Reviewed by: tuexen
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D25611
Use PVO_PADDR macro to get the physical address from a PVO, instead of
explicitly ANDing pvo_pte.pa with LPTE_RPGN where it is needed. Besides
improving readability, this is needed to support superpages (D25237), where
the steps to get the PA from a PVO are different.
Reviewed by: markj
Sponsored by: Eldorado Research Institute (eldorado.org.br)
Differential Revision: https://reviews.freebsd.org/D25654
* Only read the DPCPU pointer once per xive_dispatch call.
* Optimize HE decoding for the common cases.
Reported by: jhibbits (in irc)
Reviewed by: jhibbits
Sponsored by: Tag1 Consulting, Inc.
Differential Revision: https://reviews.freebsd.org/D25545
It turns out relocating the symbol table itself can cause issues, like fbt
crashing because it applies the offsets to the kernel twice.
This had been previously brought up in rS333447 when the stoffs hack was
added, but I had been unaware of this and reimplemented symtab relocation.
Instead of relocating the symbol table, keep track of the relocation base
in ddb, so the ddb symbols behave like the kernel linker-provided symbols.
This is intended to be NFC on platforms other than PowerPC, which do not
use fully relocatable kernels. (The relbase will always be 0)
* Remove the rest of the stoffs hack.
* Remove my half-baked displace_symbol_table() function.
* Extend ddb initialization to cope with having a relocation offset on the
kernel symbol table.
* Fix my kernel-as-initrd hack to work with booke64 by using a temporary
mapping to access the data.
* Fix another instance of __powerpc__ that is actually RELOCATABLE_KERNEL.
* Change the behavior or X_db_symbol_values to apply the relocation base
when updating valp, to match link_elf_symbol_values() behavior.
Reviewed by: jhibbits
Sponsored by: Tag1 Consulting, Inc.
Differential Revision: https://reviews.freebsd.org/D25223
Due to kldxref not being able to generate hints for nonnative platforms,
any cross built VM images do not have /boot/kernel/linker.hints.
This prevents the virtio modules from being loaded, as the fallback code
will always fail the version check when the hints are missing.
Since we want to be able to generate VM images for 32 bit powerpc, add the
virtio modules to GENERIC like we do on powerpc64.
Reviewed by: jhibbits
Sponsored by: Tag1 Consulting, Inc.
Differential Revision: https://reviews.freebsd.org/D25271
Since qemu does not implement the L2 cache, we get stuck forever waiting
for a bit to be set when trying to invalidate it.
To prevent that, we should bail out if the L2 cache is missing.
One easy way to check this is L2CFG0 == 0 (since L2CSIZE always has at
least one bit set in a valid implementation)
(tested on qemu, rb800, and x5000)
Reviewed by: jhibbits
Sponsored by: Tag1 Consulting, Inc.
Differential Revision: https://reviews.freebsd.org/D25225
After r361988 fixed the reference count leak on booke64, it became possible
for an iteration somewhere in the middle of a page to become stale, with the
page vanishing (correctly) due to all PTEs on that page going away.
pte_find_next() would start at that iterator, and move along 'higher' order
directory pages until it finds a valid one, without zeroing out the lower
order pages. For instance:
/* Find next pte at or above 0x10002000. */
pte = pte_find_next(pmap, &(0x10002000));
pte_remove(pmap, pte);
/* This pte was the last reference in the page table page, page is
* gone.
*/
pte = pte_find_next(pmap, 0x10002000);
/* pte_find_next will see 0x10002000's page is gone, and jump to the
* next one, but starting iteration at the '0x2000' slot, skipping
* 0x0000 and 0x1000.
*/
This caused some processes, like git, to trip the KASSERT() in
pmap_release().
Fix this by zeroing all lower order iterators at each level.
vmem quantum cache is only needed when doing a lot of concurrent allocations,
which doesn't happen when allocating MSIs. This wastes memory for the cache
zones. Avoid this waste and don't use the quantum cache.
Reported by: markj
Properly handle reference counts in the 64-bit pmap page directories.
Otherwise all page table pages would leak due to over-referencing. This
would cause a quick enter to swap on a desktop system (AmigaOne X5000) when
quitting and rerunning applications, or just building world.
Add an INVARIANTS check to validate no leakage at pmap release time.
If the POWER firmware detects a bad CPU core, it will "GUARD" it out,
marking it disabled. Any attempt to spin up a bad CPU will trigger a panic
later on when waiting for threads on said core to wake up. Support limping
along on fewer cores instead.
Summary:
Radix on AIM, and all of Book-E (currently), can do direct addressing of
user space, instead of needing to map user addresses into kernel space.
Take advantage of this to optimize the copy(9) functions for this
behavior, and avoid effectively NOP translations.
Test Plan: Tested on powerpcspe, powerpc64/booke, powerpc64/AIM
Reviewed by: bdragon
Differential Revision: https://reviews.freebsd.org/D25129
Summary:
The point of this addition is to cache CPU behavior 'features', to avoid
having to recompute based on CPU, etc.
The first such use case is to avoid the unnecessary manipulation of the
SLBs (Segment Lookaside Buffers) when using the Radix pmap on POWER9.
Since we already get the PCPU pointer wherever we swap the SLB entries,
we can use a cached flag to check if it's necessary to perform the
operation anyway, and skip it when not.
Reviewed by: bdragon
Differential Revision: https://reviews.freebsd.org/D24908
HTM is on the chopping block, doesn't work on FreeBSD, and has only token
support in PowerISA 3.1 and POWER10. Don't advertise something we'll never
support.
Found by running libc tests with radix enabled.
Detect unsigned integer wrapping with a postcondition.
Note: Radix MMU is not enabled by default yet.
Sponsored by: Tag1 Consulting, Inc.
With IFUNC support in the kernel, we can finally get rid of our poor-man's
ifunc for pmap, utilizing kobj. Since moea64 uses a second tier kobj as
well, for its own private methods, this adds a second pmap install function
(pmap_mmu_init()) to perform pmap 'post-install pre-bootstrap'
initialization, before the IFUNCs get initialized.
Reviewed by: bdragon
In this context, 0 actually means 0 (i.e. this is a li instruction).
While most assemblers will ignore this, I did have a compile failure at one
point when using an external toolchain.
In the future, we should use the li syntax to make this clearer.
Sponsored by: Tag1 Consulting, Inc.
A recent kernel change caused the previously unused atomic_cmpset_masked() to
be used.
It had a typo in it.
Instead of reading the old value from an uninitialized variable, read it
from the passed-in pointer as intended.
This fixes crashes on 64 bit Book-E.
Obtained from: jhibbits
Kernel page tables actually start at index 4096, given kernel base address
of 0xc008000000000000, not index 0, which would yield 0xc000000000000000.
Fix this by indexing at the real base, instead of the assumed base.
This is a correctness fix needed to enable the ifunc conversion of the pmap
in D24993.
Since we are making function calls that may need to go through the PLT, ensure
r30 is set up correctly.
This fixes crashes when booting with D24993 applied.
Reviewed by: jhibbits (in IRC)
Sponsored by: Tag1 Consulting, Inc.
This reapplies logical r360944 and r360946 (reverting r360955), with fixed
copystr() stand-in replacement macro. Eventually the goal is to convert
consumers and kill the macro, but for a first step it helps if the macro is
correct.
Prior commit message:
Unlike the other copy*() functions, it does not serve to copy from one
address space to another or protect against potential faults. It's just
an older incarnation of the now-more-common strlcpy().
Add a coccinelle script to tools/ which can be used to mechanically
convert existing instances where replacement with strlcpy is trivial.
In the two cases which matched, fuse_vfsops.c and union_vfsops.c, the
code was further refactored manually to simplify.
Replace the declaration of copystr() in systm.h with a small macro
wrapper around strlcpy (with correction from brooks@ -- thanks).
Remove N redundant MI implementations of copystr. For MIPS, this
entailed inlining the assembler copystr into the only consumer,
copyinstr, and making the latter a leaf function.
Reviewed by: jhb (earlier version)
Discussed with: brooks (thanks!)
Differential Revision: https://reviews.freebsd.org/D24672
Recent changes have caused the vmspace objects to start coming from KVA
instead of direct-mapped memory on powerpc. As far as I can tell, this is
not actually a problem, so we should stop arbitrarily asserting that it is.
I do not know why this was not being triggered before.
Approved by: jhibbits
Sponsored by: Tag1 Consulting, Inc.
Instead of crashing the user process when a D-ERAT multihit is detected, try
to flush the ERAT, and continue. This machine check indicates a likely PMAP
invalidation shortcoming that will need to be addressed, but it's
recoverable, so just recover. The recovery is pmap-specific to flush the
ERAT, so add a pmap function to do so, currently only implemented by the
POWER9 radix pmap.
x86 needs delayed TLB invalidation because invalidation requires an
expensive IPI. PowerPC has had a TLB invalidation instruction since the
POWER1 in 1990, so there's no need to delay anything.
A page (even physmem) can be marked as cache-inhibited. Attempting to use
'dcbz' to zero a page mapped cache-inhibited triggers an alignment
exception, which is fatal in kernel. This was seen when testing hardware
acceleration with X on POWER9.
At some point in the future, this should be changed to a more straight
forward zero loop instead of bzero(), and a similar change be made to the
other pmaps.
Reported by: pkubaj@
The most likely users of the QORIQ64 config nowadays are users of AmigaOne
X5000 systems, which are desktops. They need a framebuffer and
keyboard/mouse, so add these to the config so it works by default once
drm-current-kmod is installed.
TRAP_ENTRY(0) should be TRAP_GENTRAP(0) here.
However, in practice, it doesn't matter, as the only time TRAP_ENTRY and
TRAP_GENTRAP can differ is when bridge mode is active, which is impossible
on the 64 bit kernel.
Fix it anyway in case we ever need to add a trap preamble on PPC64.
Unlike the other copy*() functions, it does not serve to copy from one
address space to another or protect against potential faults. It's just
an older incarnation of the now-more-common strlcpy().
Add a coccinelle script to tools/ which can be used to mechanically
convert existing instances where replacement with strlcpy is trivial.
In the two cases which matched, fuse_vfsops.c and union_vfsops.c, the
code was further refactored manually to simplify.
Replace the declaration of copystr() in systm.h with a small macro
wrapper around strlcpy.
Remove N redundant MI implementations of copystr. For MIPS, this
entailed inlining the assembler copystr into the only consumer,
copyinstr, and making the latter a leaf function.
Reviewed by: jhb
Differential Revision: https://reviews.freebsd.org/D24672
Summary:
POWER9 supports two MMU formats: traditional hashed page tables, and Radix
page tables, similar to what's presesnt on most other architectures. The
PowerISA also specifies a process table -- a table of page table pointers--
which on the POWER9 is only available with the Radix MMU, so we can take
advantage of it with the Radix MMU driver.
Written by Matt Macy.
Differential Revision: https://reviews.freebsd.org/D19516
Summary:
Some machine checks are process-recoverable, others are not. Let a
CPU-specific handler decide what to do.
This works around a machine check error hit while building www/firefox
and mail/thunderbird, which would otherwise cause the build to fail.
More work is needed to handle all possible machine check conditions, but
this is sufficient to unblock some ports building.
Differential Revision: https://reviews.freebsd.org/D23731
This is a general cleanup of the relocatable kernel support on powerpc,
needed to enable kernel ifuncs.
* Fix some relocatable issues in the kernel linker, and change to using
a RELOCATABLE_KERNEL #define instead of #ifdef __powerpc__ for parts that
other platforms can use in the future if they wish to have ET_DYN kernels.
* Get rid of the DB_STOFFS hack now that the kernel is relocated to the DMAP
properly across the board on powerpc64.
* Add powerpc64 and powerpc32 ifunc functionality.
* Allow AIM64 virtual mode OF kernels to run from the DMAP like other AIM64
by implementing a virtual mode restart. This fixes the runtime address on
PowerMac G5.
* Fix symbol relocation problems on post-relocation kernels by relocating
the symbol table.
* Add an undocumented method for supplying kernel symbols on powernv and
other powerpc machines using linux-style kernel/initrd loading -- If
you pass the kernel in as the initrd as well, the copy resident in initrd
will be used as a source for symbols when initializing the debugger.
This method is subject to removal once we have a better way of doing this.
Approved by: jhibbits
Relnotes: yes
Sponsored by: Tag1 Consulting, Inc.
Differential Revision: https://reviews.freebsd.org/D23156
The comment referenced a non-existent function, and these minidump
implementations already buffer discontiguous physical data pages by
mapping them into a single VA range that gets passed to the dump device,
so there is no real advantage in batching calls to blk_write().
The RISC-V and MIPS minidump implementations still write a page at a
time and so would benefit from some form of batching.
MFC after: 2 weeks
Sponsored by: Juniper Networks, Klara Inc.
Use AUXARGS_ENTRY_PTR to export these pointers. This is a followup to
r359987 and r359988.
Reviewed by: jhb
Obtained from: CheriBSD
Sponsored by: DARPA
Differential Revision: https://reviews.freebsd.org/D24446
Default moea64_bpvo_pool_size 327680 was insufficient for initial
memory mapping at boot time on systems with, for example, 64G and
no huge pages enabled.
Submitted by: Andre Silva <afscoelho@gmail.com>
Reviewed by: jhibbits, alfredo
Approved by: jhibbits (mentor)
Sponsored by: Eldorado Research Institute (eldorado.org.br)
Differential Revision: https://reviews.freebsd.org/D24102
Summary:
This reduces the precious TLB1 entry consumption (64 possible in
existing 64-bit cores), by adjusting the size and alignment of a device
mapping to a power of 2, to encompass the full mapping and its
surroundings.
One caveat with this: If a mapping really is smaller than a power of 2,
it's possible to get a machine check or hang if the 'missing' physical
space is accessed. In practice this should not be an issue for users,
as devices overwhelmingly have physical spaces on power-of-two sizes and
alignments, and any design that includes devices which don't follow this
can be addressed by undefining the POW2_MAPPINGS guard.
Reviewed by: bdragon
Differential Revision: https://reviews.freebsd.org/D24248
Summary:
Iterating over VM_MIN_ADDRESS->VM_MAXUSER_ADDRESS can take a very long
time iterating one page at a time (2**(log_2(SIZE)-12) operations),
yielding possibly several days or even weeks on 64-bit Book-E, even for
a largely empty, which can happen when swapping out a process by
vmdaemon. Speed this up by instead finding the next PTE at or equal to
the given VA.
Reviewed by: bdragon
Differential Revision: https://reviews.freebsd.org/D24238
Summary:
The existing page table is fraught with errors, since it creates a hole
in the address space bits. Fix this by taking a cue from the POWER9
radix pmap, and make the page table 4 levels, 52 bits.
Reviewed by: bdragon
Differential Revision: https://reviews.freebsd.org/D24220
Like the X5000, the main CPLD on the A1222 is the communication medium
between the CPU and the GPIO CPLD. It provides a mailbox communication
feature, along with dual-port RAM accessible from both the CPU and GPIO
CPLD, and 3 fan speed reporting registers.
Modern debuggers and process tracers use ptrace() rather than procfs
for debugging. ptrace() has a supserset of functionality available
via procfs and new debugging features are only added to ptrace().
While the two debugging services share some fields in struct proc,
they each use dedicated fields and separate code. This results in
extra complexity to support a feature that hasn't been enabled in the
default install for several years.
PR: 244939 (exp-run)
Reviewed by: kib, mjg (earlier version)
Relnotes: yes
Differential Revision: https://reviews.freebsd.org/D23837
The goal of this change is to make the atomic_load_acq_{8,16},
atomic_testandset{,_acq}_long, and atomic_testandclear_long primitives
available in MI-namespace.
The second goal is to get this draft out of my local tree, as anything that
requires a full tinderbox is a big burden out of tree. MD specifics can be
refined individually afterwards.
The generic implementations may not be ideal for your architecture; feel
free to implement better versions. If no subword_atomic definitions are
needed, the include can be removed from your arch's machine/atomic.h.
Generic definitions are guarded by defined macros of the same name. To
avoid picking up conflicting generic definitions, some macro defines are
added to various MD machine/atomic.h to register an existing implementation.
Include _atomic_subword.h in arm and arm64 machine/atomic.h.
For some odd reason, KCSAN only generates some versions of primitives.
Generate the _acq variants of atomic_load.*_8, atomic_load.*_16, and
atomic_testandset.*_long. There are other questionably disabled primitives,
but I didn't run into them, so I left them alone. KCSAN is only built for
amd64 in tinderbox for now.
Add atomic_subword implementations of atomic_load_acq_{8,16} implemented
using masking and atomic_load_acq_32.
Add generic atomic_subword implementations of atomic_testandset_long(),
atomic_testandclear_long(), and atomic_testandset_acq_long(), using
atomic_fcmpset_long() and atomic_fcmpset_acq_long().
On x86, add atomic_testandset_acq_long as an alias for
atomic_testandset_long.
Reviewed by: kevans, rlibby (previous versions both)
Differential Revision: https://reviews.freebsd.org/D22963
This fixes /dev/kmem causing panic on machines not using DMAP.
Found when running libkvm Kyua test case on QEMU VM with no
Huge Pages support.
Reviewed by: jhibbits, luporl
Approved by: jhibbits (mentor)
Sponsored by: Eldorado Research Institute (eldorado.org.br)
Differential Revision: https://reviews.freebsd.org/D23776
When I implemented MD DYNAMIC parsing, I was originally passing a
linker_file_t so that the MD code could relocate pointers.
However, it turns out this isn't even filled in until later, so it was
always 0.
Just pass the load base (ef->address) directly, as that's really the only
thing we were interested in in the first place.
This fixes a crash on RB800 where it was trying to write to an unmapped
address when updating the GOT.
Reviewed by: jhibbits
Sponsored by: Tag1 Consulting, Inc.
Differential Revision: https://reviews.freebsd.org/D24105
Summary:
The support was added almost a decade ago, and never completed. Just axe
it. It was also inadvertently broken 5 years ago, and nobody noticed.
Reviewed by: bdragon
Differential Revision: https://reviews.freebsd.org/D23753
The ixl driver now works on PowerPC64 and may be compiled in-kernel and
as a module.
Reviewed by: alfredo, erj
Sponsored by: Eldorado Research Institute (eldorado.org.br)
Differential Revision: https://reviews.freebsd.org/D23974
Summary:
This is largely a straight-forward cleave of the 32-bit and 64-bit page
table specifics, along with the mmu_booke_*() functions that are wholely
different between the two implementations.
The ultimate goal of this is to make it easier to reason about and
update a specific implementation without wading through the other
implementation details. This is in support of further changes to the 64-bit
pmap.
Reviewed by: bdragon
Differential Revision: https://reviews.freebsd.org/D23983
Replace hardcoded sizes by nitems and sizeof
Replace CTLFLAG_NEEDGIANT with CTLFLAG_MPSAFE, I run this driver since a few
years with CTLFLAG_MPSAFE w/o issues.
32-bit Book-E doesn't set UMA_MD_SMALL_ALLOC, and 32-bit OEA platforms
have a 32-bit vm_paddr_t. Moreover, this code was wrong in that it
leaked the page if the check failed.
Reviewed by: jhibbits
MFC after: 1 week
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D23991
Port aacraid driver to big-endian (BE) hosts.
The immediate goal of this change is to make it possible to use the
aacraid driver on PowerPC64 machines that have Adaptec Series 8 SAS
controllers.
Adapters supported by this driver expect FIB contents in little-endian
(LE) byte order. All FIBs have a fixed header part as well as a data
part that depends on the command being issued to the controller.
In this way, on BE hosts, the FIB header and all FIB data structures
used in aacraid.c and aacraid_cam.c need to be converted to LE before
being sent to the adapter and converted to BE when coming from it.
The functions to convert each struct are on aacraid_endian.c.
For little-endian (LE) targets, they are macros that expand
to nothing.
In some cases, when only a few fields of a large structure are used,
the fields are converted inline, by the code using them.
PR: 237463
Reviewed by: jhibbits
Sponsored by: Eldorado Research Institute (eldorado.org.br)
Differential Revision: https://reviews.freebsd.org/D23887
Fix panic "Freeing UMA block at 0xn with no associated page".
Also replaces pmap_remove call by pmap_kremove, for symmetry.
Reviewed by: jhibbits
Approved by: jhibbits (mentor)
Differential Revision: https://reviews.freebsd.org/D23931
If NUMA is not enabled in the kernel config, or is disabled at boot, this
function should just return domain 0 regardless of what's in the device
tree.
Fixes a panic in iflib with NUMA disabled.
Reported by: luporl
r357614 added CTLFLAG_NEEDGIANT to make it easier to find nodes that are
still not MPSAFE (or already are but aren’t properly marked).
Use it in preparation for a general review of all nodes.
This is non-functional change that adds annotations to SYSCTL_NODE and
SYSCTL_PROC nodes using one of the soon-to-be-required flags.
Mark all obvious cases as MPSAFE. All entries that haven't been marked
as MPSAFE before are by default marked as NEEDGIANT
Approved by: kib (mentor, blanket)
Commented by: kib, gallatin, melifaro
Differential Revision: https://reviews.freebsd.org/D23718
Since powerpc64 has such a large virtual address space, significantly larger
than its physical address space, take advantage of this, and create yet
another DMAP-like instance for the device mappings. In this case, the
device mapping "DMAP" is in the 0x8000000000000000 - 0xc000000000000000
range, so as not to overlap the physical memory DMAP.
This will allow us to add TLB1 entry coalescing in the future, especially
useful for things like the radeonkms driver, which maps parts of the GPU at
a time, but eventually maps all of it, using up a lot of TLB1 entries (~40).
ptbl_alloc() is expected to return with the pvh_global_lock and pmap
lock held. However, it will return with them unlocked if nosleep is
specified.
Along with this, fix lock ordering of pvh_global_lock with respect to
the pmap lock in other places.
Differential Revision: https://reviews.freebsd.org/D23692
PR: 244118
Reported by: Francis Little <oggy at farscape.co.uk>
Tested by: Francis Little, Mark Millard <marklmi at yahoo.com>
Reviewed by: markj
Sponsored by: Dell EMC Isilon
Differential Revision: https://reviews.freebsd.org/D23729
We somewhat blindly copy the srr1 from the new context to the trap frame,
but disable FPU and VSX unconditionally, relying on the trap to re-enable
them. This works because the FPU manages the VSX extended FP registers,
which is governed by the PCB_FPFREGS flag. However, with altivec, we
would blindly disable PSL_VEC, without touching PCB_VEC. Handle this case
by disabling altivec in both srr1 and pcb_flags, if the mcontext doesn't
have _MC_AV_VALID set.
Reported by: pkubaj
This reverts r177661. The change is no longer very useful since
out-of-tree KLDs will be built to target SMP kernels anyway. Moveover
it breaks the KBI in !SMP builds since cpuset_t's layout depends on the
value of MAXCPU, and several kernel interfaces, notably
smp_rendezvous_cpus(), take a cpuset_t as a parameter.
PR: 243711
Reviewed by: jhb, kib
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D23512
Remove mbuf_jumbo_alloc and let large mbuf zones use the new uma default
contig allocator (a copy of mbuf_jumbo_alloc). Tag other zones which
require contiguous objects, even if they don't use the new default
contig allocator, so that uma knows about their constraints.
Reviewed by: jeff, markj
Sponsored by: Dell EMC Isilon
Differential Revision: https://reviews.freebsd.org/D23238
In r356767, memcpy/memmove/bcopy optimizations were added to libc to
improve performance.
This exposed an existing kernel issue in VSX handling. The PSL_VSX flag was
not being excluded from the psl_userstatic set, which meant that any thread
that used these and then called swapcontext(3) would get an EINVAL error.
Fixing this exposed a second issue - in r344123, the FPU was being forced
off in set_mcontext(). However, this was neglecting to ensure VSX was turned
off at the same time.
While here, add some code comments to explain what's going on.
Reviewed by: jhibbits, luporl (earlier rev), pkubaj (earlier rev)
Sponsored by: Tag1 Consulting, Inc.
Differential Revision: https://reviews.freebsd.org/D23497
After r355784 the td_oncpu field is no longer synchronized by the thread
lock, so the stack capture interrupt cannot be delievered precisely.
Fix this using a loop which drops the thread lock and restarts if the
wrong thread was sampled from the stack capture interrupt handler.
Change the implementation to use a regular interrupt instead of an NMI.
Now that we drop the thread lock, there is no advantage to the latter.
Simplify the KPIs. Remove stack_save_td_running() and add a return
value to stack_save_td(). On platforms that do not support stack
capture of running threads, stack_save_td() returns EOPNOTSUPP. If the
target thread is running in user mode, stack_save_td() returns EBUSY.
Reviewed by: kib
Reported by: mjg, pho
Tested by: pho
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D23355
On some POWER8 machines, 'ibm,associativity' property may have 6
cells, which would overflow the 5 cells buffer being used.
There was also an issue with the "check if node is root" part,
that have been fixed too.
Reviewed by: jhibbits
Differential Revision: https://reviews.freebsd.org/D23414
Summary:
The CPLD is the communications medium between the CPU and the XMOS
"Xena" event coprocessor. It provides a mailbox communication feature,
along with dual-port RAM to be used between the CPU and XMOS. Also, it
provides basic board stats as well, such as PCIe presence, JTAG signals,
and CPU fan speed reporting (in revolutions per second). Only fan speed
reading is handled, as a sysctl.
Reviewed by: bdragon
Differential Revision: https://reviews.freebsd.org/D23136
Summary:
This fixes kernel crashing when tunable "machdep.moea64_bpvo_pool_size" is
set to a value higher then 327680 (default value). Function
moea64_mid_bootstrap() relies on moea64_bpvo_pool_size, but at time of the
use the variable wan't yet updated with the new value provided by user.
Problem was detected after trying to use a VM with 64GB of RAM, and default
moea64_bpvo_pool_size is insufficient (kernel boot used more than 470000) .
I think default value must be discussed to address this use case, or find a
way to calculate pool size automatically based on amount of memory detected.
Test Plan: Tested on QEMU VM with 64GB of RAM using "set
machdep.moea64_bpvo_pool_size=655360" on loader prompt
Submitted by: Alfredo Dal'Ava Júnior (alfredo.junior_eldorado.org.br)
Differential Revision: https://reviews.freebsd.org/D23233
In rS354701, I replaced text relocations with offsets from &generictrap.
Unfortunately, the magic variable I was using doesn't actually mean the
address of &generictrap, in bridge mode it actually means &generictrap64.
So, for bridge mode to work, it is necessary to differentiate between
"where do we need to branch to to handle a trap" and "where is &generictrap
for purposes of doing relative math".
Introduce a new TRAP_ENTRY and use it instead of TRAP_GENTRAP for doing
actual calls to the generic trap handler.
Reported by: Mark Millard <marklmi@yahoo.com>
Reviewed by: jhibbits
Sponsored by: Tag1 Consulting, Inc.
Differential Revision: https://reviews.freebsd.org/D23057
Summary:
This makes the interface described in the definition file act like a
pseudo-IFUNC service, by caching the found method locally.
Applying this to the PowerPC MMU definitions, it yields a significant
(15-20%) performance improvement, seen in both a 'make buildworld' and a
parallel build of LLVM, on a POWER9 system.
Reviewed By: imp
Differential Revision: https://reviews.freebsd.org/D23245
Summary:
Consolidate the NUMA associativity handling into a platform function.
Non-NUMA platforms will just fall back to the default (0). Currently
only implemented for powernv, which uses a lookup table to map the
device tree associativity into a system NUMA domain.
Fixes hangs on powernv after r356534, and corrects a fairly longstanding
bug in powernv's NUMA handling, which ended up using domains 1 and 2 for
devices and memory on power9, while CPUs were bound to domains 0 and 1.
Reviewed by: bdragon, luporl
Differential Revision: https://reviews.freebsd.org/D23220
It turns out the maximum TLB1 page size on e5500 is 4G, despite the format
being defined for up to 1TB.
So, we need to clamp the DMAP TLB1 entries to not attempt to create 16G or
larger entries.
Fixes boot on my X5000 in which I just installed 16G of RAM.
Reviewed by: jhibbits
Sponsored by: Tag1 Consulting, Inc.
Differential Revision: https://reviews.freebsd.org/D23244
In r291668, an instruction was added to sigcode64.S without the nop pad at
the end being taken out.
Due to alignment, this means that a dword is being wasted on the shared
page for no reason.
Take out this nop, and add some comments while I'm here.
Reviewed by: jhibbits
Sponsored by: Tag1 Consulting, Inc.
Differential Revision: https://reviews.freebsd.org/D23055
This enables virtio modules on PowerPC* target.
On PowerPC64, drivers are also kernel builtin.
QEMU currently needs to be patched to in order to work on LE hosts due to known
issue affecting pre-1.0 (legacy) virtio drivers.
The patch was submitted to QEMU mail list by @afscoelho_gmail.com, available at
https://lists.nongnu.org/archive/html/qemu-devel/2020-01/msg01496.html
Submitted by: Alfredo Dal'Ava Junior <alfredo.junior@eldorado.org.br>
Reviewed by: luporl
Differential Revision: https://reviews.freebsd.org/D22833
r302340, as an attempt to fix the localbus child handling post-rman change,
actually broke child resource allocation, due to typos in
fdt_lbc_reg_decode(). This went unnoticed because there aren't any drivers
currently in tree that use localbus.
hw.floatingpoint and hw.altivec are effectively runtime constants (bits from
the cpu_feature bitfield), so don't need Giant, or any locking for that
matter.
It may be possible to make this completely lock free, but for now it's using
a statically allocated bounce buffer in the softc, so it needs to be
guarded.
This is a lock-based emulation of 64-bit atomics for kernel use, split off
from an earlier patch by jhibbits.
This is needed to unblock future improvements that reduce the need for
locking on 64-bit platforms by using atomic updates.
The implementation allows for future integration with userland atomic64,
but as that implies going through sysarch for every use, the current
status quo of userland doing its own locking may be for the best.
Submitted by: jhibbits (original patch), kevans (mips bits)
Reviewed by: jhibbits, jeff, kevans
Differential Revision: https://reviews.freebsd.org/D22976
In IRC, sfs_ finally managed to get a good trace of a kernel panic that was
happening when attempting to use webengine.
As it turns out, we were using vtophys() from interrupt context on an idle
thread in opal_hmi_handler2().
Since this involves locking the kernel pmap on PPC64 at the moment, this
ended up tripping a KASSERT in mtx_lock(), which then caused a parallel
panic stampede.
So, avoid this by preallocating the flags variable and storing it in PCPU.
Fixes "panic: mtx_lock() by idle thread 0x... on sleep mutex kernelpmap".
Differential Revision: https://reviews.freebsd.org/D22962
Due to a bug in clang 9.0.0 source tracking, the trap vector copying will
always trigger a fortify-source warning.
The destination buffers are 0x2f00 bytes, and the bcopy region is 0x2e00
bytes, so there is not an overflow here.
(I have been running with this patch since September.)
Summary:
r356113 used an older patch, which predated the
freebsd_copyout_auxargs() addition. Fix this by using a private
powerpc_copyout_auxargs() instead, and keep it private to powerpc, not in MI
files.
Reviewed by: kib, bdragon
Differential Revision: https://reviews.freebsd.org/D22935
This is a prerequisite for anything IFUNC in the ELFv2 / clang switch.
Since probing cpu info on powerpc is a privileged operation, define that we
pass AT_HWCAP / AT_HWCAP2 through as cpu_features and cpu_features2 to ifunc
resolvers.
This is particularly important when dealing with non-PLT GNU IFUNC, which is
not allowed to PLT call from resolvers and therefore can't access global
variables.
The naming convention "cpu_features"/"cpu_features2" is an existing FreeBSD
PowerPC convention and matches the way we treat these variables in
machine/cpu.h.
The underlying variables are u_long, however, as per the commit message for
r332868, only the low 32 bits are ever used, so the underlying flags are
compatible across all of PowerPC.
The resolver prototype is defined to reserve the maximum number of
register-passed parameters the various PowerPC ABIs allow. This leaves
plenty of room for growth without needing to resort to passing via the
stack in the future.
Reviewed by: jhibbits
Differential Revision: https://reviews.freebsd.org/D22787
Due to clang and LLD's tendency to use a PLT for builtins, and as they
don't have full support for EABI, we sometimes have to deal with a PLT in
.ko files in a clang-built kernel.
As such, augment the in-kernel linker to support jump table processing.
As there is no particular reason to support lazy binding in kernel modules,
only implement Secure-PLT immediate binding.
As part of these changes, add elf_cpu_parse_dynamic() to the MD API of the
in-kernel linker (except on platforms that use raw object files.)
The new function will allow MD code to act on MD tags in _DYNAMIC.
Use this new function in the PowerPC MD code to ensure BSS-PLT modules using
PLT will be rejected during insertion, and to poison the runtime resolver to
ensure we get a clear panic reason if a call is made to the resolver.
Reviewed by: jhibbits
Differential Revision: https://reviews.freebsd.org/D22608
off the stack, initialized to default values, and then filled in with
driver-specific values, all without having to worry about the numerous
other fields in the tag. The resulting template is then passed into
busdma and the normal opaque tag object created. See the man page for
details on how to initialize a template.
Templates do not support tag filters. Filters have been broken for many
years, and only existed for an ancient make/model of hardware that had a
quirky DMA engine. Instead of breaking the ABI/API and changing the
arugment signature of bus_dma_tag_create() to remove the filter arguments,
templates allow us to ignore them, and also significantly reduce the
complexity of creating and managing tags.
Reviewed by: imp, kib
Differential Revision: https://reviews.freebsd.org/D22906
As far as I can tell, these are an artifact of times when linker sets
couldn't be empty, otherwise the kernel build would fail due to unresolved
symbols. hselasky fixed this in r268138, and I've audited the kbd portions
to make sure nothing would blow up due to the empty linker set and
successfully compiled+ran a kernel with no keyboard support at all.
Kill them off now since they're no longer required.
MFC after: 1 week
fix an assert violation introduced in r355784. Without this spinlock_exit()
may see owepreempt and switch before reducing the spinlock count. amd64
had been optimized to do a single critical enter/exit regardless of the
number of spinlocks which avoided the problem and this optimization had
not been applied elsewhere.
Reported by: emaste
Suggested by: rlibby
Discussed with: jhb, rlibby
Tested by: manu (arm64)
On PowerPC, this is needed in order for the debugger to find out
the memory offset where the kernel image was loaded on the remote
target.
This fixes symbol resolution when remote debugging a PowerPC kernel.
Reviewed by: cem
Differential Revision: https://reviews.freebsd.org/D22767
The Nest MMU manages address translation for accelerators on the POWER9. To
do so, it needs a page table, so export the system page table to the Nest
MMU. This will quietly fail on pre-POWER9 systems that do not have a NMMU.
The NMMU is currently unused, so this change is currently effectively a NOP,
but the NMMU and VAS will eventually be used.
Fix multiple problems in the powerpcspe floating point code.
* Endianness handling of the SPEFSCR in fenv.h was completely broken.
* Ensure SPEFSCR synchronization requirements are being met.
The __r.__d -> __r transformations were written by jhibbits.
Reviewed by: jhibbits
Differential Revision: https://reviews.freebsd.org/D22526
Due to ppc32 building mmu_oea64.c (for use when in bridge mode on a G5), we
need to guard the new moea64_page_array_startup code behind __powerpc64__
to avoid a compile error, since vm_offset_t is not 64-bit on ppc32.
Reviewed by: jhibbits
Differential Revision: https://reviews.freebsd.org/D22782
This is a 32-bit structure embedded in each vm_page, consisting mostly
of page queue state. The use of a structure makes it easy to store a
snapshot of a page's queue state in a stack variable and use cmpset
loops to update that state without requiring the page lock.
This change merely adds the structure and updates references to atomic
state fields. No functional change intended.
Reviewed by: alc, jeff, kib
Sponsored by: Netflix, Intel
Differential Revision: https://reviews.freebsd.org/D22650
This change enables the use of OpenFirmware Console (ofwcons), even when VGA is
available, allowing early kernel messages to be seen, that is important in case
of crashes before VGA console initialization.
This is specially useful in virtualized environments, where the user/developer
doesn't have full control of the virtualization engine (e.g. OpenStack).
The old behavior is preserved by default and, in order to use ofwcons, a few
tunables that have been introduced need to be set:
- hw.ofwfb.disable=1 - disable OFW FrameBuffer device
- machdep.ofw.mtx_spin=1 - change PPC OFW mutex to SPIN type, to match kernel
console's mutex type
- debug.quiesce_ofw=0 - don't call OFW quiesce, needed to keep ofwcons I/O
working
More details can be found at differential revision D20640.
Reviewed by: jhibbits
Differential Revision: https://reviews.freebsd.org/D20640
This change makes it possible to use OPAL console as a GDB debug port.
Similar to uart and uart_phyp debug ports, it has to be enabled by
setting the hw.uart.dbgport variable to the serial console node
of the device tree.
Reviewed by: jhibbits
Differential Revision: https://reviews.freebsd.org/D22649
Summary:
There's no need to use the fallback fls() and flsl() libkern functions
when the PowerISA includes instructions that already do the bulk of the
work. Take advantage of this through the GCC builtins __builtin_clz()
and __builtin_clzl().
Reviewed by: luporl
Differential Revision: https://reviews.freebsd.org/D22340
Summary:
moea64_pte_sync_native() and moea64_pte_unset_native() don't need the
full PTE created, they only need to check that the PVO has a matching
PTE to the PTE in the page table. Don't waste time creating the full
PTE in this case.
Reviewed by: luporl
Differential Revision: https://reviews.freebsd.org/D22341
Summary:
This matches r351198 from amd64. This only applies to AIM64 and Book-E.
On AIM64 it short-circuits with one domain, to behave similar to
existing. Otherwise it will allocate 16MB huge pages to hold the page
array, across all NUMA domains. On the first domain it will shift the
page array base up, to "upper-align" the page array in that domain, so
as to reduce the number of pages from the next domain appearing in this
domain. After the first domain, subsequent domains will be allocated in
full 16MB pages, until the final domain, which can be short. This means
some inner domains may have pages accounted in earlier domains.
On Book-E the page array is setup at MMU bootstrap time so that it's
always mapped in TLB1, on both 32-bit and 64-bit. This reduces the TLB0
overhead for touching the vm_page_array, which reduces up to one TLB
miss per array access.
Since page_range (vm_page_startup()) is no longer used on Book-E but is on
32-bit AIM, mark the variable as potentially unused, rather than using a
nasty #if defined() list.
Reviewed by: luporl
Differential Revision: https://reviews.freebsd.org/D21449
o Remove All Rights Reserved from my notices
o imp@FreeBSD.org everywhere
o regularize punctiation, eliminate date ranges
o Make sure that it's clear that I don't claim All Rights reserved by listing
All Rights Reserved on same line as other copyright holders (but not
me). Other such holders are also listed last where it's clear.
Use the right formats for the types given (vm_offset_t and vm_size_t are
both uint32_t on 32-bit platforms, and uint64_t on 64-bit platforms, and
match size_t in size, so we can use the size_t format as we do in other
similar code).
These were found by clang.
r354266 changed the type of bp_kernload to vm_paddr_t in platform_mpc85xx.c,
but not the variable itself in locore.S. This caused the AP to not come up,
due to overwriting the following variable (bp_virtaddr). Also, properly
load bp_kernload into MAS3 and MAS7. Prior to r354266, we required loading
into the low 4GB, but now we can load from anywhere in memory that ubldr can
access.
- Use ustringp for the location of the argv and environment strings
and allow destp to travel further down the stack for the stackgap
and auxv regions.
- Update the Linux copyout_strings variants to move destp down the
stack as was done for the native ABIs in r263349.
- Stop allocating a space for a stack gap in the Linux ABIs. This
used to hold translated system call arguments, but hasn't been used
since r159992.
Reviewed by: kib
Tested on: md64 (amd64, i386, linux64), i386 (i386, linux)
Sponsored by: DARPA
Differential Revision: https://reviews.freebsd.org/D22501
This lets us print, for example, the user's trap frame when a panic occurs.
The frame address is given in the backtrace at the trap point, which can
then be passed to 'show frame'. This is useful for debugging as it can show
inputs that lead to a panic or fault. It can also be used to print trap
frames from other CPUs that get stuck.
i386 already has a similar command, but no others do.
As part of my journey to make it easy to determine what's relying on tty
bits, remove a couple more. Some of these just outright didn't need it,
while others did rely on <sys/tty.h> pollution for mutex headers.
Since version 2.11.0, QEMU became bug-compatible with
PowerVM's vty implementation, by inserting a \0 after
every \r going to the guest. Guests are expected to
workaround this issue by removing every \0 immediately
following a \r.
Reviewed by: jhibbits
Differential Revision: https://reviews.freebsd.org/D22171
