Some firmware supplies PCI host bridge _CRS that includes address space
unusable by PCI devices, e.g., space occupied by host bridge registers or
used by hidden PCI devices.
To avoid this unusable space, Linux currently excludes E820 reserved
regions from _CRS windows; see 4dc2287c18 ("x86: avoid E820 regions when
allocating address space").
However, this use of E820 reserved regions to clip things out of _CRS is
not supported by ACPI, UEFI, or PCI Firmware specs, and some systems have
E820 reserved regions that cover the entire memory window from _CRS.
4dc2287c18 clips the entire window, leaving no space for hot-added or
uninitialized PCI devices.
For example, from a Lenovo IdeaPad 3 15IIL 81WE:
BIOS-e820: [mem 0x4bc50000-0xcfffffff] reserved
pci_bus 0000:00: root bus resource [mem 0x65400000-0xbfffffff window]
pci 0000:00:15.0: BAR 0: [mem 0x00000000-0x00000fff 64bit]
pci 0000:00:15.0: BAR 0: no space for [mem size 0x00001000 64bit]
Future patches will add quirks to enable/disable E820 clipping
automatically.
Add a "pci=no_e820" kernel command line option to disable clipping with
E820 reserved regions. Also add a matching "pci=use_e820" option to enable
clipping with E820 reserved regions if that has been disabled by default by
further patches in this patch-set.
Both options taint the kernel because they are intended for debugging and
workaround purposes until a quirk can set them automatically.
[bhelgaas: commit log, add printk]
Link: https://bugzilla.redhat.com/show_bug.cgi?id=1868899 Lenovo IdeaPad 3
Link: https://lore.kernel.org/r/20220519152150.6135-2-hdegoede@redhat.com
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Benoit Grégoire <benoitg@coeus.ca>
Cc: Hui Wang <hui.wang@canonical.com>
The deferred probe timer that's used for this currently starts at
late_initcall and runs for driver_deferred_probe_timeout seconds. The
assumption being that all available drivers would be loaded and
registered before the timer expires. This means, the
driver_deferred_probe_timeout has to be pretty large for it to cover the
worst case. But if we set the default value for it to cover the worst
case, it would significantly slow down the average case. For this
reason, the default value is set to 0.
Also, with CONFIG_MODULES=y and the current default values of
driver_deferred_probe_timeout=0 and fw_devlink=on, devices with missing
drivers will cause their consumer devices to always defer their probes.
This is because device links created by fw_devlink defer the probe even
before the consumer driver's probe() is called.
Instead of a fixed timeout, if we extend an unexpired deferred probe
timer on every successful driver registration, with the expectation more
modules would be loaded in the near future, then the default value of
driver_deferred_probe_timeout only needs to be as long as the worst case
time difference between two consecutive module loads.
So let's implement that and set the default value to 10 seconds when
CONFIG_MODULES=y.
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Rob Herring <robh@kernel.org>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Will Deacon <will@kernel.org>
Cc: Ulf Hansson <ulf.hansson@linaro.org>
Cc: Kevin Hilman <khilman@kernel.org>
Cc: Thierry Reding <treding@nvidia.com>
Cc: Mark Brown <broonie@kernel.org>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Cc: Paul Kocialkowski <paul.kocialkowski@bootlin.com>
Cc: linux-gpio@vger.kernel.org
Cc: linux-pm@vger.kernel.org
Cc: iommu@lists.linux-foundation.org
Reviewed-by: Mark Brown <broonie@kernel.org>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Saravana Kannan <saravanak@google.com>
Link: https://lore.kernel.org/r/20220429220933.1350374-1-saravanak@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There's currently no way to use driver_async_probe kernel cmdline param
to enable default async probe for all drivers. So, add support for "*"
to match with all driver names. When "*" is used, all other drivers
listed in driver_async_probe are drivers that will NOT match the "*".
For example:
* driver_async_probe=drvA,drvB,drvC
drvA, drvB and drvC do asynchronous probing.
* driver_async_probe=*
All drivers do asynchronous probing except those that have set
PROBE_FORCE_SYNCHRONOUS flag.
* driver_async_probe=*,drvA,drvB,drvC
All drivers do asynchronous probing except drvA, drvB, drvC and those
that have set PROBE_FORCE_SYNCHRONOUS flag.
Cc: Alexander Duyck <alexander.h.duyck@linux.intel.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Feng Tang <feng.tang@intel.com>
Signed-off-by: Saravana Kannan <saravanak@google.com>
Link: https://lore.kernel.org/r/20220504005344.117803-1-saravanak@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When "crashkernel=X,high" is specified, the specified "crashkernel=Y,low"
memory is not required in the following corner cases:
1. If both CONFIG_ZONE_DMA and CONFIG_ZONE_DMA32 are disabled, it means
that the devices can access any memory.
2. If the system memory is small, the crash high memory may be allocated
from the DMA zones. If that happens, there's no need to allocate
another crash low memory because there's already one.
Add condition '(crash_base >= CRASH_ADDR_LOW_MAX)' to determine whether
the 'high' memory is allocated above DMA zones. Note: when both
CONFIG_ZONE_DMA and CONFIG_ZONE_DMA32 are disabled, the entire physical
memory is DMA accessible, CRASH_ADDR_LOW_MAX equals 'PHYS_MASK + 1'.
Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com>
Acked-by: Baoquan He <bhe@redhat.com>
Link: https://lore.kernel.org/r/20220511032033.426-1-thunder.leizhen@huawei.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Currently both expedited and regular grace period stall warnings use
a single timeout value that with units of seconds. However, recent
Android use cases problem require a sub-100-millisecond expedited RCU CPU
stall warning. Given that expedited RCU grace periods normally complete
in far less than a single millisecond, especially for small systems,
this is not unreasonable.
Therefore introduce the CONFIG_RCU_EXP_CPU_STALL_TIMEOUT kernel
configuration that defaults to 20 msec on Android and remains the same
as that of the non-expedited stall warnings otherwise. It also can be
changed in run-time via: /sys/.../parameters/rcu_exp_cpu_stall_timeout.
[ paulmck: Default of zero to use CONFIG_RCU_STALL_TIMEOUT. ]
Signed-off-by: Uladzislau Rezki <uladzislau.rezki@sony.com>
Signed-off-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Cleanup the text text describing the libata.force boot parameter and
update the list of the values to include all supported horkage and link
flag that can be forced.
Signed-off-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
In preparation to differentiate between unsigned regular IMA file
hashes and fs-verity's file digests in the IMA measurement list,
define a new template field named 'd-ngv2'.
Also define two new templates named 'ima-ngv2' and 'ima-sigv2', which
include the new 'd-ngv2' field.
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
This commit adds a srcutree.convert_to_big option of zero that causes
SRCU to decide at boot whether to wait for contention (small systems) or
immediately expand to large (large systems). A new srcutree.big_cpu_lim
(defaulting to 128) defines how many CPUs constitute a large system.
Co-developed-by: Neeraj Upadhyay <quic_neeraju@quicinc.com>
Signed-off-by: Neeraj Upadhyay <quic_neeraju@quicinc.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Debugging of problems involving insanely long-running SMI handlers
proceeds better if the CSD-lock timeout can be adjusted. This commit
therefore provides a new smp.csd_lock_timeout kernel boot parameter
that specifies the timeout in milliseconds. The default remains at the
previously hard-coded value of five seconds.
[ paulmck: Apply feedback from Juergen Gross. ]
Cc: Rik van Riel <riel@surriel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Reviewed-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Move some out-of-place kernel parameters into their correct
locations.
Move one out-of-order keyword/legend in kernel-parameters.rst.
Add some missing keyword legends in kernel-parameters.rst:
HIBERNATION HYPER_V
and drop some obsolete/removed keyword legends:
EIDE IOSCHED OSS TS XT
Correct the location of the setup.h file.
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: linux-doc@vger.kernel.org
Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Cc: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
x86 EFI earlyprink was removed with commit 69c1f396f2 ("efi/x86:
Convert x86 EFI earlyprintk into generic earlycon implementation").
Signed-off-by: Akihiko Odaki <akihiko.odaki@gmail.com>
Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
RCU-tasks stall-warning messages are printed after the grace period is ten
minutes old. Unfortunately, most of us will have rebooted the system in
response to an apparently-hung command long before the ten minutes is up,
and will thus see what looks to be a silent hang.
This commit therefore adds pr_info() messages that are printed earlier.
These should avoid being classified as errors, but should give impatient
users a hint. These are controlled by new rcupdate.rcu_task_stall_info
and rcupdate.rcu_task_stall_info_mult kernel-boot parameters. The former
defines the initial delay in jiffies (defaulting to 10 seconds) and the
latter defines the multiplier (defaulting to 3). Thus, by default, the
first message will appear 10 seconds into the RCU-tasks grace period,
the second 40 seconds in, and the third 160 seconds in. There would be
a fourth at 640 seconds in, but the stall warning message appears 600
seconds in, and once a stall warning is printed for a given grace period,
no further informational messages are printed.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
This commit instruments the acquisitions of the srcu_struct structure's
->lock, enabling the initiation of a transition from SRCU_SIZE_SMALL
to SRCU_SIZE_BIG when sufficient contention is experienced. The
instrumentation counts the number of trylock failures within the confines
of a single jiffy. If that number exceeds the value specified by the
srcutree.small_contention_lim kernel boot parameter (which defaults to
100), and if the value specified by the srcutree.convert_to_big kernel
boot parameter has the 0x10 bit set (defaults to 0), then a transition
will be automatically initiated.
By default, there will never be any transitions, so that none of the
srcu_struct structures ever gains an srcu_node array.
The useful values for srcutree.convert_to_big are:
0x00: Never convert.
0x01: Always convert at init_srcu_struct() time.
0x02: Convert when rcutorture prints its first round of statistics.
0x03: Decide conversion approach at boot given system size.
0x10: Convert if contention is encountered.
0x12: Convert if contention is encountered or when rcutorture prints
its first round of statistics, whichever comes first.
The value 0x11 acts the same as 0x01 because the conversion happens
before there is any chance of contention.
[ paulmck: Apply "static" feedback from kernel test robot. ]
Co-developed-by: Neeraj Upadhyay <quic_neeraju@quicinc.com>
Signed-off-by: Neeraj Upadhyay <quic_neeraju@quicinc.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
This commit adds an srcu_tree.convert_to_big kernel parameter that either
refuses to convert at all (0), converts immediately at init_srcu_struct()
time (1), or lets rcutorture convert it (2). An addition contention-based
dynamic conversion choice will be added, along with documentation.
[ paulmck: Apply callback-scanning feedback from Neeraj Upadhyay. ]
Co-developed-by: Neeraj Upadhyay <quic_neeraju@quicinc.com>
Signed-off-by: Neeraj Upadhyay <quic_neeraju@quicinc.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
For debugging purposes it is very useful to have a way to see the full
contents of the SNP CPUID table provided to a guest. Add an sev=debug
kernel command-line option to do so.
Also introduce some infrastructure so that additional options can be
specified via sev=option1[,option2] over time in a consistent manner.
[ bp: Massage, simplify string parsing. ]
Suggested-by: Borislav Petkov <bp@alien8.de>
Signed-off-by: Michael Roth <michael.roth@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lore.kernel.org/r/20220307213356.2797205-41-brijesh.singh@amd.com
Those were added as part of the SMAP enablement but SMAP is currently
an integral part of kernel proper and there's no need to disable it
anymore.
Rip out that functionality. Leave --uaccess default on for objtool as
this is what objtool should do by default anyway.
If still needed - clearcpuid=smap.
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Lai Jiangshan <jiangshanlai@gmail.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20220127115626.14179-4-bp@alien8.de
That chicken bit was added by
4f88651125 ("[PATCH] i386: allow disabling X86_FEATURE_SEP at boot")
but measuring int80 vsyscall performance on 32-bit doesn't matter
anymore.
If still needed, one can boot with
clearcpuid=sep
to disable that feature for testing.
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20220127115626.14179-3-bp@alien8.de
Having to give the X86_FEATURE array indices in order to disable a
feature bit for testing is not really user-friendly. So accept the
feature bit names too.
Some feature bits don't have names so there the array indices are still
accepted, of course.
Clearing CPUID flags is not something which should be done in production
so taint the kernel too.
An exemplary cmdline would then be something like:
clearcpuid=de,440,smca,succory,bmi1,3dnow
("succory" is wrong on purpose). And it says:
[ ... ] Clearing CPUID bits: de 13:24 smca (unknown: succory) bmi1 3dnow
[ Fix CONFIG_X86_FEATURE_NAMES=n build error as reported by the 0day
robot: https://lore.kernel.org/r/202203292206.ICsY2RKX-lkp@intel.com ]
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20220127115626.14179-2-bp@alien8.de
If CONFIG_RANDOM_TRUST_CPU is set, the RNG initializes using RDRAND.
But, the user can disable (or enable) this behavior by setting
`random.trust_cpu=0/1` on the kernel command line. This allows system
builders to do reasonable things while avoiding howls from tinfoil
hatters. (Or vice versa.)
CONFIG_RANDOM_TRUST_BOOTLOADER is basically the same thing, but regards
the seed passed via EFI or device tree, which might come from RDRAND or
a TPM or somewhere else. In order to allow distros to more easily enable
this while avoiding those same howls (or vice versa), this commit adds
the corresponding `random.trust_bootloader=0/1` toggle.
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: Graham Christensen <graham@grahamc.com>
Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Dominik Brodowski <linux@dominikbrodowski.net>
Link: https://github.com/NixOS/nixpkgs/pull/165355
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Merge more updates from Andrew Morton:
"Various misc subsystems, before getting into the post-linux-next
material.
41 patches.
Subsystems affected by this patch series: procfs, misc, core-kernel,
lib, checkpatch, init, pipe, minix, fat, cgroups, kexec, kdump,
taskstats, panic, kcov, resource, and ubsan"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (41 commits)
Revert "ubsan, kcsan: Don't combine sanitizer with kcov on clang"
kernel/resource: fix kfree() of bootmem memory again
kcov: properly handle subsequent mmap calls
kcov: split ioctl handling into locked and unlocked parts
panic: move panic_print before kmsg dumpers
panic: add option to dump all CPUs backtraces in panic_print
docs: sysctl/kernel: add missing bit to panic_print
taskstats: remove unneeded dead assignment
kasan: no need to unset panic_on_warn in end_report()
ubsan: no need to unset panic_on_warn in ubsan_epilogue()
panic: unset panic_on_warn inside panic()
docs: kdump: add scp example to write out the dump file
docs: kdump: update description about sysfs file system support
arm64: mm: use IS_ENABLED(CONFIG_KEXEC_CORE) instead of #ifdef
x86/setup: use IS_ENABLED(CONFIG_KEXEC_CORE) instead of #ifdef
riscv: mm: init: use IS_ENABLED(CONFIG_KEXEC_CORE) instead of #ifdef
kexec: make crashk_res, crashk_low_res and crash_notes symbols always visible
cgroup: use irqsave in cgroup_rstat_flush_locked().
fat: use pointer to simple type in put_user()
minix: fix bug when opening a file with O_DIRECT
...
Pull kvm updates from Paolo Bonzini:
"ARM:
- Proper emulation of the OSLock feature of the debug architecture
- Scalibility improvements for the MMU lock when dirty logging is on
- New VMID allocator, which will eventually help with SVA in VMs
- Better support for PMUs in heterogenous systems
- PSCI 1.1 support, enabling support for SYSTEM_RESET2
- Implement CONFIG_DEBUG_LIST at EL2
- Make CONFIG_ARM64_ERRATUM_2077057 default y
- Reduce the overhead of VM exit when no interrupt is pending
- Remove traces of 32bit ARM host support from the documentation
- Updated vgic selftests
- Various cleanups, doc updates and spelling fixes
RISC-V:
- Prevent KVM_COMPAT from being selected
- Optimize __kvm_riscv_switch_to() implementation
- RISC-V SBI v0.3 support
s390:
- memop selftest
- fix SCK locking
- adapter interruptions virtualization for secure guests
- add Claudio Imbrenda as maintainer
- first step to do proper storage key checking
x86:
- Continue switching kvm_x86_ops to static_call(); introduce
static_call_cond() and __static_call_ret0 when applicable.
- Cleanup unused arguments in several functions
- Synthesize AMD 0x80000021 leaf
- Fixes and optimization for Hyper-V sparse-bank hypercalls
- Implement Hyper-V's enlightened MSR bitmap for nested SVM
- Remove MMU auditing
- Eager splitting of page tables (new aka "TDP" MMU only) when dirty
page tracking is enabled
- Cleanup the implementation of the guest PGD cache
- Preparation for the implementation of Intel IPI virtualization
- Fix some segment descriptor checks in the emulator
- Allow AMD AVIC support on systems with physical APIC ID above 255
- Better API to disable virtualization quirks
- Fixes and optimizations for the zapping of page tables:
- Zap roots in two passes, avoiding RCU read-side critical
sections that last too long for very large guests backed by 4
KiB SPTEs.
- Zap invalid and defunct roots asynchronously via
concurrency-managed work queue.
- Allowing yielding when zapping TDP MMU roots in response to the
root's last reference being put.
- Batch more TLB flushes with an RCU trick. Whoever frees the
paging structure now holds RCU as a proxy for all vCPUs running
in the guest, i.e. to prolongs the grace period on their behalf.
It then kicks the the vCPUs out of guest mode before doing
rcu_read_unlock().
Generic:
- Introduce __vcalloc and use it for very large allocations that need
memcg accounting"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (246 commits)
KVM: use kvcalloc for array allocations
KVM: x86: Introduce KVM_CAP_DISABLE_QUIRKS2
kvm: x86: Require const tsc for RT
KVM: x86: synthesize CPUID leaf 0x80000021h if useful
KVM: x86: add support for CPUID leaf 0x80000021
KVM: x86: do not use KVM_X86_OP_OPTIONAL_RET0 for get_mt_mask
Revert "KVM: x86/mmu: Zap only TDP MMU leafs in kvm_zap_gfn_range()"
kvm: x86/mmu: Flush TLB before zap_gfn_range releases RCU
KVM: arm64: fix typos in comments
KVM: arm64: Generalise VM features into a set of flags
KVM: s390: selftests: Add error memop tests
KVM: s390: selftests: Add more copy memop tests
KVM: s390: selftests: Add named stages for memop test
KVM: s390: selftests: Add macro as abstraction for MEM_OP
KVM: s390: selftests: Split memop tests
KVM: s390x: fix SCK locking
RISC-V: KVM: Implement SBI HSM suspend call
RISC-V: KVM: Add common kvm_riscv_vcpu_wfi() function
RISC-V: Add SBI HSM suspend related defines
RISC-V: KVM: Implement SBI v0.3 SRST extension
...
The panic_print setting allows users to collect more information in a
panic event, like memory stats, tasks, CPUs backtraces, etc. This is an
interesting debug mechanism, but currently the print event happens *after*
kmsg_dump(), meaning that pstore, for example, cannot collect a dmesg with
the panic_print extra information.
This patch changes that in 2 steps:
(a) The panic_print setting allows to replay the existing kernel log
buffer to the console (bit 5), besides the extra information dump.
This functionality makes sense only at the end of the panic()
function. So, we hereby allow to distinguish the two situations by a
new boolean parameter in the function panic_print_sys_info().
(b) With the above change, we can safely call panic_print_sys_info()
before kmsg_dump(), allowing to dump the extra information when using
pstore or other kmsg dumpers.
The additional messages from panic_print could overwrite the oldest
messages when the buffer is full. The only reasonable solution is to use
a large enough log buffer, hence we added an advice into the kernel
parameters documentation about that.
Link: https://lkml.kernel.org/r/20220214141308.841525-1-gpiccoli@igalia.com
Signed-off-by: Guilherme G. Piccoli <gpiccoli@igalia.com>
Acked-by: Baoquan He <bhe@redhat.com>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Reviewed-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Feng Tang <feng.tang@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Currently the "panic_print" parameter/sysctl allows some interesting debug
information to be printed during a panic event. This is useful for
example in cases the user cannot kdump due to resource limits, or if the
user collects panic logs in a serial output (or pstore) and prefers a fast
reboot instead of a kdump.
Happens that currently there's no way to see all CPUs backtraces in a
panic using "panic_print" on architectures that support that. We do have
"oops_all_cpu_backtrace" sysctl, but although partially overlapping in the
functionality, they are orthogonal in nature: "panic_print" is a panic
tuning (and we have panics without oopses, like direct calls to panic() or
maybe other paths that don't go through oops_enter() function), and the
original purpose of "oops_all_cpu_backtrace" is to provide more
information on oopses for cases in which the users desire to continue
running the kernel even after an oops, i.e., used in non-panic scenarios.
So, we hereby introduce an additional bit for "panic_print" to allow
dumping the CPUs backtraces during a panic event.
Link: https://lkml.kernel.org/r/20211109202848.610874-3-gpiccoli@igalia.com
Signed-off-by: Guilherme G. Piccoli <gpiccoli@igalia.com>
Reviewed-by: Feng Tang <feng.tang@intel.com>
Cc: Iurii Zaikin <yzaikin@google.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Luis Chamberlain <mcgrof@kernel.org>
Cc: Samuel Iglesias Gonsalvez <siglesias@igalia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull tracing updates from Steven Rostedt:
- New user_events interface. User space can register an event with the
kernel describing the format of the event. Then it will receive a
byte in a page mapping that it can check against. A privileged task
can then enable that event like any other event, which will change
the mapped byte to true, telling the user space application to start
writing the event to the tracing buffer.
- Add new "ftrace_boot_snapshot" kernel command line parameter. When
set, the tracing buffer will be saved in the snapshot buffer at boot
up when the kernel hands things over to user space. This will keep
the traces that happened at boot up available even if user space boot
up has tracing as well.
- Have TRACE_EVENT_ENUM() also update trace event field type
descriptions. Thus if a static array defines its size with an enum,
the user space trace event parsers can still know how to parse that
array.
- Add new TRACE_CUSTOM_EVENT() macro. This acts the same as the
TRACE_EVENT() macro, but will attach to an existing tracepoint. This
will make one tracepoint be able to trace different content and not
be stuck at only what the original TRACE_EVENT() macro exports.
- Fixes to tracing error logging.
- Better saving of cmdlines to PIDs when tracing (use the wakeup events
for mapping).
* tag 'trace-v5.18' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (30 commits)
tracing: Have type enum modifications copy the strings
user_events: Add trace event call as root for low permission cases
tracing/user_events: Use alloc_pages instead of kzalloc() for register pages
tracing: Add snapshot at end of kernel boot up
tracing: Have TRACE_DEFINE_ENUM affect trace event types as well
tracing: Fix strncpy warning in trace_events_synth.c
user_events: Prevent dyn_event delete racing with ioctl add/delete
tracing: Add TRACE_CUSTOM_EVENT() macro
tracing: Move the defines to create TRACE_EVENTS into their own files
tracing: Add sample code for custom trace events
tracing: Allow custom events to be added to the tracefs directory
tracing: Fix last_cmd_set() string management in histogram code
user_events: Fix potential uninitialized pointer while parsing field
tracing: Fix allocation of last_cmd in last_cmd_set()
user_events: Add documentation file
user_events: Add sample code for typical usage
user_events: Add self-test for validator boundaries
user_events: Add self-test for perf_event integration
user_events: Add self-test for dynamic_events integration
user_events: Add self-test for ftrace integration
...
Pull printk updates from Petr Mladek:
- Make %pK behave the same as %p for kptr_restrict == 0 also with
no_hash_pointers parameter
- Ignore the default console in the device tree also when console=null
or console="" is used on the command line
- Document console=null and console="" behavior
- Prevent a deadlock and a livelock caused by console_lock in panic()
- Make console_lock available for panicking CPU
- Fast query for the next to-be-used sequence number
- Use the expected return values in printk.devkmsg __setup handler
- Use the correct atomic operations in wake_up_klogd() irq_work handler
- Avoid possible unaligned access when handling %4cc printing format
* tag 'printk-for-5.18' of git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux:
printk: fix return value of printk.devkmsg __setup handler
vsprintf: Fix %pK with kptr_restrict == 0
printk: make suppress_panic_printk static
printk: Set console_set_on_cmdline=1 when __add_preferred_console() is called with user_specified == true
Docs: printk: add 'console=null|""' to admin/kernel-parameters
printk: use atomic updates for klogd work
printk: Drop console_sem during panic
printk: Avoid livelock with heavy printk during panic
printk: disable optimistic spin during panic
printk: Add panic_in_progress helper
vsprintf: Move space out of string literals in fourcc_string()
vsprintf: Fix potential unaligned access
printk: ringbuffer: Improve prb_next_seq() performance
Patch series "Free the 2nd vmemmap page associated with each HugeTLB
page", v7.
This series can minimize the overhead of struct page for 2MB HugeTLB
pages significantly. It further reduces the overhead of struct page by
12.5% for a 2MB HugeTLB compared to the previous approach, which means
2GB per 1TB HugeTLB. It is a nice gain. Comments and reviews are
welcome. Thanks.
The main implementation and details can refer to the commit log of patch
1. In this series, I have changed the following four helpers, the
following table shows the impact of the overhead of those helpers.
+------------------+-----------------------+
| APIs | head page | tail page |
+------------------+-----------+-----------+
| PageHead() | Y | N |
+------------------+-----------+-----------+
| PageTail() | Y | N |
+------------------+-----------+-----------+
| PageCompound() | N | N |
+------------------+-----------+-----------+
| compound_head() | Y | N |
+------------------+-----------+-----------+
Y: Overhead is increased.
N: Overhead is _NOT_ increased.
It shows that the overhead of those helpers on a tail page don't change
between "hugetlb_free_vmemmap=on" and "hugetlb_free_vmemmap=off". But the
overhead on a head page will be increased when "hugetlb_free_vmemmap=on"
(except PageCompound()). So I believe that Matthew Wilcox's folio series
will help with this.
The users of PageHead() and PageTail() are much less than compound_head()
and most users of PageTail() are VM_BUG_ON(), so I have done some tests
about the overhead of compound_head() on head pages.
I have tested the overhead of calling compound_head() on a head page,
which is 2.11ns (Measure the call time of 10 million times
compound_head(), and then average).
For a head page whose address is not aligned with PAGE_SIZE or a
non-compound page, the overhead of compound_head() is 2.54ns which is
increased by 20%. For a head page whose address is aligned with
PAGE_SIZE, the overhead of compound_head() is 2.97ns which is increased by
40%. Most pages are the former. I do not think the overhead is
significant since the overhead of compound_head() itself is low.
This patch (of 5):
This patch minimizes the overhead of struct page for 2MB HugeTLB pages
significantly. It further reduces the overhead of struct page by 12.5%
for a 2MB HugeTLB compared to the previous approach, which means 2GB per
1TB HugeTLB (2MB type).
After the feature of "Free sonme vmemmap pages of HugeTLB page" is
enabled, the mapping of the vmemmap addresses associated with a 2MB
HugeTLB page becomes the figure below.
HugeTLB struct pages(8 pages) page frame(8 pages)
+-----------+ ---virt_to_page---> +-----------+ mapping to +-----------+---> PG_head
| | | 0 | -------------> | 0 |
| | +-----------+ +-----------+
| | | 1 | -------------> | 1 |
| | +-----------+ +-----------+
| | | 2 | ----------------^ ^ ^ ^ ^ ^
| | +-----------+ | | | | |
| | | 3 | ------------------+ | | | |
| | +-----------+ | | | |
| | | 4 | --------------------+ | | |
| 2MB | +-----------+ | | |
| | | 5 | ----------------------+ | |
| | +-----------+ | |
| | | 6 | ------------------------+ |
| | +-----------+ |
| | | 7 | --------------------------+
| | +-----------+
| |
| |
| |
+-----------+
As we can see, the 2nd vmemmap page frame (indexed by 1) is reused and
remaped. However, the 2nd vmemmap page frame is also can be freed to
the buddy allocator, then we can change the mapping from the figure
above to the figure below.
HugeTLB struct pages(8 pages) page frame(8 pages)
+-----------+ ---virt_to_page---> +-----------+ mapping to +-----------+---> PG_head
| | | 0 | -------------> | 0 |
| | +-----------+ +-----------+
| | | 1 | ---------------^ ^ ^ ^ ^ ^ ^
| | +-----------+ | | | | | |
| | | 2 | -----------------+ | | | | |
| | +-----------+ | | | | |
| | | 3 | -------------------+ | | | |
| | +-----------+ | | | |
| | | 4 | ---------------------+ | | |
| 2MB | +-----------+ | | |
| | | 5 | -----------------------+ | |
| | +-----------+ | |
| | | 6 | -------------------------+ |
| | +-----------+ |
| | | 7 | ---------------------------+
| | +-----------+
| |
| |
| |
+-----------+
After we do this, all tail vmemmap pages (1-7) are mapped to the head
vmemmap page frame (0). In other words, there are more than one page
struct with PG_head associated with each HugeTLB page. We __know__ that
there is only one head page struct, the tail page structs with PG_head are
fake head page structs. We need an approach to distinguish between those
two different types of page structs so that compound_head(), PageHead()
and PageTail() can work properly if the parameter is the tail page struct
but with PG_head.
The following code snippet describes how to distinguish between real and
fake head page struct.
if (test_bit(PG_head, &page->flags)) {
unsigned long head = READ_ONCE(page[1].compound_head);
if (head & 1) {
if (head == (unsigned long)page + 1)
==> head page struct
else
==> tail page struct
} else
==> head page struct
}
We can safely access the field of the @page[1] with PG_head because the
@page is a compound page composed with at least two contiguous pages.
[songmuchun@bytedance.com: restore lost comment changes]
Link: https://lkml.kernel.org/r/20211101031651.75851-1-songmuchun@bytedance.com
Link: https://lkml.kernel.org/r/20211101031651.75851-2-songmuchun@bytedance.com
Signed-off-by: Muchun Song <songmuchun@bytedance.com>
Reviewed-by: Barry Song <song.bao.hua@hisilicon.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Michal Hocko <mhocko@suse.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Chen Huang <chenhuang5@huawei.com>
Cc: Bodeddula Balasubramaniam <bodeddub@amazon.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Xiongchun Duan <duanxiongchun@bytedance.com>
Cc: Fam Zheng <fam.zheng@bytedance.com>
Cc: Qi Zheng <zhengqi.arch@bytedance.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull hwmon updates from Guenter Roeck:
"New drivers:
- Texas Instruments TMP464 and TMP468 driver
- Vicor PLI1209BC Digital Supervisor driver
- ASUS EC driver
Improvements to existing drivers:
- adt7x10:
- Convert to use regmap
- convert to use with_info API
- use hwmon_notify_event
- other cleanup
- aquacomputer_d5next:
- Add support for Aquacomputer Farbwerk 360
- asus_wmi_sensors:
- Add ASUS ROG STRIX B450-F GAMING II
- asus_wmi_ec_sensors:
- Support T_Sensor on Prime X570-Pro
- Deprecate driver (replaced by new driver)
- axi-fan-control:
- Use hwmon_notify_event
- dell-smm:
- Clean up CONFIG_I8K
- disable fan type support for Inspiron 3505
- various other cleanup
- hwmon core:
- Report attribute name with udev events
- Add "label" attribute to ABI,
- Add support for pwm auto channels attribute
- max6639:
- Add regulator support
- lm70:
- Add support for TI TMP125
- lm83:
- Cleanup, convert to use with_info API
- mlxreg-fan:
- Use pwm attribute for setting fan speed low limit
- nct6775:
- Add board ID's for ASUS ROG STRIX Z390/Z490/X570-* / PRIME
X570-P, PRIME B550-PLUS, ASUS Pro B550M-C/PRIME B550M-A
- Add support for TSI temperature registers
- occ:
- Add various new sysfs attributes
- pmbus core:
- Handle VIN unit off status
- Add regulator supply into macro
- Add get_error_flags support to regulator ops
- pmbus/adm1275:
- Allow setting sample averaging
- pmbus/lm25066:
- Add regulator support
- pmbus/xdpe12284:
- Add support for xdpe11280
- register as regulator
- powr1220:
- Convert to with_info API
- Add support for Lattice's POWR1014 power manager IC
- sch56xx:
- Cleanup and minor improvements
- sch5627:
- Add pwmX_auto_channels_temp support
- tc654:
- Add thermal_cooling device support"
* tag 'hwmon-for-v5.18' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging: (86 commits)
hwmon: (dell-smm) Add Inspiron 3505 to fan type blacklist
hwmon: (pmbus) Add Vin unit off handling
hwmon: (scpi-hwmon): Use of_device_get_match_data()
hwmon: (axi-fan-control) Use hwmon_notify_event
hwmon: (vexpress-hwmon) Use of_device_get_match_data()
hwmon: Add driver for Texas Instruments TMP464 and TMP468
dt-bindings: hwmon: add tmp464.yaml
dt-bindings: hwmon: Add sample averaging properties for ADM1275
hwmon: (adm1275) Allow setting sample averaging
hwmon: (xdpe12284) Add regulator support
hwmon: (xdpe12284) Add support for xdpe11280
dt-bindings: trivial-devices: Add xdpe11280
hwmon: (aquacomputer_d5next) Add support for Aquacomputer Farbwerk 360
hwmon: (sch5627) Add pwmX_auto_channels_temp support
hwmon: (core) Add support for pwm auto channels attribute
hwmon: (lm70) Add ti,tmp125 support
dt-bindings: Add ti,tmp125 temperature sensor binding
hwmon: (pmbus/pli1209bc) Add regulator support
hwmon: (pmbus) Add support for pli1209bc
dt-bindings:trivial-devices: Add pli1209bc
...
Pull documentation updates from Jonathan Corbet:
"It has been a moderately busy cycle for documentation; some of the
highlights are:
- Numerous PDF-generation improvements
- Kees's new document with guidelines for researchers studying the
development community.
- The ongoing stream of Chinese translations
- Thorsten's new document on regression handling
- A major reworking of the internal documentation for the kernel-doc
script.
Plus the usual stream of typo fixes and such"
* tag 'docs-5.18' of git://git.lwn.net/linux: (80 commits)
docs/kernel-parameters: update description of mem=
docs/zh_CN: Add sched-nice-design Chinese translation
docs: scheduler: Convert schedutil.txt to ReST
Docs: ktap: add code-block type
docs: serial: fix a reference file name in driver.rst
docs: UML: Mention telnetd for port channel
docs/zh_CN: add damon reclaim translation
docs/zh_CN: add damon usage translation
docs/zh_CN: add admin-guide damon start translation
docs/zh_CN: add admin-guide damon index translation
docs/zh_CN: Refactoring the admin-guide directory index
zh_CN: Add translation for admin-guide/mm/index.rst
zh_CN: Add translations for admin-guide/mm/ksm.rst
Add Chinese translation for vm/ksm.rst
docs/zh_CN: Add sched-stats Chinese translation
docs/zh_CN: add devicetree of_unittest translation
docs/zh_CN: add devicetree usage-model translation
docs/zh_CN: add devicetree index translation
Documentation: describe how to apply incremental stable patches
docs/zh_CN: add peci subsystem translation
...
Pull RCU updates from Paul McKenney:
- Fix idle detection (Neeraj Upadhyay) and missing access marking
detected by KCSAN.
- Reduce coupling between rcu_barrier() and CPU-hotplug operations, so
that rcu_barrier() no longer needs to do cpus_read_lock(). This may
also someday allow system boot to bring CPUs online concurrently.
- Enable more aggressive movement to per-CPU queueing when reacting to
excessive lock contention due to workloads placing heavy update-side
stress on RCU tasks.
- Improvements to RCU priority boosting, including changes from Neeraj
Upadhyay, Zqiang, and Alison Chaiken.
- Various fixes improving test robustness and debug information.
- Add tests for SRCU size transitions, further compress torture.sh
build products, and improve debug output.
- Miscellaneous fixes.
* tag 'rcu.2022.03.13a' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu: (49 commits)
rcu: Replace cpumask_weight with cpumask_empty where appropriate
rcu: Remove __read_mostly annotations from rcu_scheduler_active externs
rcu: Uninline multi-use function: finish_rcuwait()
rcu: Mark writes to the rcu_segcblist structure's ->flags field
kasan: Record work creation stack trace with interrupts enabled
rcu: Inline __call_rcu() into call_rcu()
rcu: Add mutex for rcu boost kthread spawning and affinity setting
rcu: Fix description of kvfree_rcu()
MAINTAINERS: Add Frederic and Neeraj to their RCU files
rcutorture: Provide non-power-of-two Tasks RCU scenarios
rcutorture: Test SRCU size transitions
torture: Make torture.sh help message match reality
rcu-tasks: Set ->percpu_enqueue_shift to zero upon contention
rcu-tasks: Use order_base_2() instead of ilog2()
rcu: Create and use an rcu_rdp_cpu_online()
rcu: Make rcu_barrier() no longer block CPU-hotplug operations
rcu: Rework rcu_barrier() and callback-migration logic
rcu: Refactor rcu_barrier() empty-list handling
rcu: Kill rnp->ofl_seq and use only rcu_state.ofl_lock for exclusion
torture: Change KVM environment variable to RCUTORTURE
...
Add ftrace_boot_snapshot kernel parameter that will take a snapshot at the
end of boot up just before switching over to user space (it happens during
the kernel freeing of init memory).
This is useful when there's interesting data that can be collected from
kernel start up, but gets overridden by user space start up code. With
this option, the ring buffer content from the boot up traces gets saved in
the snapshot at the end of boot up. This trace can be read from:
/sys/kernel/tracing/snapshot
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Although kptr_restrict is set to 0 and the kernel is booted with
no_hash_pointers parameter, the content of /proc/vmallocinfo is
lacking the real addresses.
/ # cat /proc/vmallocinfo
0x(ptrval)-0x(ptrval) 8192 load_module+0xc0c/0x2c0c pages=1 vmalloc
0x(ptrval)-0x(ptrval) 12288 start_kernel+0x4e0/0x690 pages=2 vmalloc
0x(ptrval)-0x(ptrval) 12288 start_kernel+0x4e0/0x690 pages=2 vmalloc
0x(ptrval)-0x(ptrval) 8192 _mpic_map_mmio.constprop.0+0x20/0x44 phys=0x80041000 ioremap
0x(ptrval)-0x(ptrval) 12288 _mpic_map_mmio.constprop.0+0x20/0x44 phys=0x80041000 ioremap
...
According to the documentation for /proc/sys/kernel/, %pK is
equivalent to %p when kptr_restrict is set to 0.
Fixes: 5ead723a20 ("lib/vsprintf: no_hash_pointers prints all addresses as unhashed")
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/107476128e59bff11a309b5bf7579a1753a41aca.1645087605.git.christophe.leroy@csgroup.eu
Update the doc with the new fun.
[ bp: Massage commit message. ]
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Remove mmu_audit.c and all its collateral, the auditing code has suffered
severe bitrot, ironically partly due to shadow paging being more stable
and thus not benefiting as much from auditing, but mostly due to TDP
supplanting shadow paging for non-nested guests and shadowing of nested
TDP not heavily stressing the logic that is being audited.
Signed-off-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
