The minidump code is written assuming that certain global state will not
change, and rightly so, since it executes from a kernel debugger
context. In order to support taking minidumps of a live system, we
should allow copies of relevant global state that is likely to change to
be passed as parameters to the minidumpsys() function.
This patch does the work of parameterizing this function, by adding a
struct minidumpstate argument. For now, this struct allows for copies of
the kernel message buffer, and the bitset that tracks which pages should
be dumped (vm_page_dump). Follow-up changes will actually make use of
these arguments.
Notably, dump_avail[] does not need a snapshot, since it is not expected
to change after system initialization.
The existing minidumpsys() definitions are renamed, and a thin MI
wrapper is added to kern_dump.c, which handles the construction of
the state struct. Thus, calling minidumpsys() remains as simple as
before.
Reviewed by: kib, markj, jhb
Sponsored by: Juniper Networks, Inc.
Sponsored by: Klara, Inc.
MFC after: 2 weeks
Differential Revision: https://reviews.freebsd.org/D31989
There is no universal way to find the TSC frequency. Newer Intel CPUs
may report it via CPUID leaves 0x15 and 0x16. Sometimes it can be
obtained from the PLATFORM_INFO MSR as well, though we never use that.
On older platforms we derive the frequency using a DELAY(1000000) call,
which uses the 8254 PIT. On some newer platforms the 8254 is apparently
non-functional, leading to bogus calibration results. On such platforms
the TSC frequency must be available from CPUID. It is also possible to
disable calibration with a tunable, in which case we try to parse the
brand string if the TSC freq is not available from CPUID.
CPUID 0x15 provides an authoritative TSC frequency value, but even that
is not always available on new Intel platforms. CPUID 0x16 provides the
specified processor base frequency, which is not the same as the TSC
frequency. Empirically, it is close enough for early boot, but too far
off for timekeeping: on a Comet Lake NUC, CPUID 0x16 yields 1600MHz but
the TSC frequency is rougly 1608MHz, leading to frequent clock stepping
when NTP is in use.
Thus we have a situation where we cannot calibrate using the PIT and
cannot obtain a precise frequency from CPUID (or MSRs). This change
seeks to address that by using the CPUID 0x16 value during early boot
and refining the calibration later once ACPI-based timecounters are
available. TSC frequency detection is thus split into two phases:
Early phase:
- On Intel platforms, query CPUID 0x15 and 0x16 and use that value
initially if available.
- Otherwise, get an estimate using the PIT, reducing the delay loop to
100ms from 1s.
- Continue to register the TSC as the CPU ticks provider early, even
though the frequency may be off. Otherwise any code executed during
boot that uses cpu_ticks() (e.g., context switching) gets tripped up
when the ticks provider changes.
Later phase:
- In SI_SUB_CLOCKS, once the timehands are initialized, load the current
TSC and timecounter (sbinuptime()) values at the beginning and end of
a 1s interval and use the timecounter frequency (typically from
kvmclock, HPET or the ACPI PM timer) to estimate the TSC frequency.
- Update the TSC timecounter, global tsc_freq and CPU ticker with the
new frequency and finally register the TSC as a timecounter.
Reviewed by: kib, jhb (previous version)
Discussed with: imp, cperciva
MFC after: 6 weeks
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D32512
We use pmap_invalidate_cpu_mask() to get the set of active CPUs. This
(32-byte) set is copied by value through multiple frames until we get to
smp_targeted_tlb_shootdown(), where it is copied yet again.
Avoid this copying by having smp_targeted_tlb_shootdown() make a local
copy of the active CPUs for the pmap, and drop the cpuset parameter,
simplifying callers. Also leverage the use of the non-destructive
CPU_FOREACH_ISSET to avoid unneeded copying within
smp_targeted_tlb_shootdown().
Reviewed by: alc, kib
Tested by: pho
MFC after: 1 month
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D32792
sched_throw() can no longer take a NULL thread, APs enter through
sched_ap_entry() instead. This completely removes branching in the
common case and cleans up both paths. No functional change intended.
Reviewed by: kib, markj
Differential Revision: https://reviews.freebsd.org/D32829
schedinit_ap() sets up an AP for a later call to sched_throw(NULL).
Currently, ULE sets up some pcpu bits and fixes the idlethread lock with
a call to sched_throw(NULL); this results in a window where curthread is
setup in platforms' init_secondary(), but it has the wrong td_lock.
Typical platform AP startup procedure looks something like:
- Setup curthread
- ... other stuff, including cpu_initclocks_ap()
- Signal smp_started
- sched_throw(NULL) to enter the scheduler
cpu_initclocks_ap() may have callouts to process (e.g., nvme) and
attempt to sched_add() for this AP, but this attempt fails because
of the noted violated assumption leading to locking heartburn in
sched_setpreempt().
Interrupts are still disabled until cpu_throw() so we're not really at
risk of being preempted -- just let the scheduler in on it a little
earlier as part of setting up curthread.
Reviewed by: alfredo, kib, markj
Triage help from: andrew, markj
Smoke-tested by: alfredo (ppc), kevans (arm64, x86), mhorne (arm)
Differential Revision: https://reviews.freebsd.org/D32797
Some BIOSes protect memory region they reside in by using DMAR to
prevent devices from doing any DMA transactions to that part of RAM.
AMI refers to this as "DMA Control Guarantee".
Disable the protection when address translation is enabled.
I stumbled upon this while investigation a failing coredump on a device
which has this feature enabled.
Sponsored by: Stormshield
Obtained from: Semihalf
Reviewed by: kib
Differential revision: https://reviews.freebsd.org/D32591
In some cases we might have to create DMAR context before the
corresponding device has been enumerated by the PCI bus.
In that case we get called with NULL dev, because of that trying
to reserve PCI regions causes a NULL pointer dereference in
pci_find_pcie_root_port.
Sponsored by: Stormshield
Obtained from: Semihalf
MFC after: 2 weeks
Reviewed by: kib, rlibby
Differential revision: https://reviews.freebsd.org/D32589
The last two drivers that required sppp are cp(4) and ce(4).
These devices are still produced and can be purchased
at Cronyx <http://cronyx.ru/hardware/wan.html>.
Since Roman Kurakin <rik@FreeBSD.org> has quit them, they no
longer support FreeBSD officially. Later they have dropped
support for Linux drivers to. As of mid-2020 they don't even
have a developer to maintain their Windows driver. However,
their support verbally told me that they could provide aid to
a FreeBSD developer with documentaion in case if there appears
a new customer for their devices.
These drivers have a feature to not use sppp(4) and create an
interface, but instead expose the device as netgraph(4) node.
Then, you can attach ng_ppp(4) with help of ports/net/mpd5 on
top of the node and get your synchronous PPP. Alternatively
you can attach ng_frame_relay(4) or ng_cisco(4) for HDLC.
Actually, last time I used cp(4) back in 2004, using netgraph(4)
instead of sppp(4) was already the right way to do.
Thus, remove the sppp(4) related part of the drivers and enable
by default the negraph(4) part. Further maintenance of these
drivers in the tree shouldn't be a big deal.
While doing that, remove some cruft and enable cp(4) compilation
on amd64. The ce(4) for some unknown reason marks its internal
DDK functions with __attribute__ fastcall, which most likely is
safe to remove, but without hardware I'm not going to do that, so
ce(4) remains i386-only.
Reviewed by: emaste, imp, donner
Differential Revision: https://reviews.freebsd.org/D32590
See also: https://reviews.freebsd.org/D23928
For some of them, used only when KTR or KMSAN are configured, apply
__unused attribute directly.
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
This implementation is faster and doesn't modify the cpuset, so it lets
us avoid some unnecessary copying as well. No functional change
intended.
This is a re-application of commit
9068f6ea69.
Reviewed by: cem, kib, jhb
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D32029
The default value for LAPIC registers page physical address
is usually right. Having this value available early makes
pmap_force_invalidate_cache_range(), used on non-self-snoop machines,
avoid flushing LAPIC range for early calls.
Reviewed by: alc, markj
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D32318
The implementation of the progress bar is simple, but duplicated for
most minidump implementations. Extract the common bits to kern_dump.c.
Ensure that the bar is reset with each subsequent dump; this was only
done on some platforms previously.
Reviewed by: markj
MFC after: 2 weeks
Sponsored by: Juniper Networks, Inc.
Sponsored by: Klara, Inc.
Differential Revision: https://reviews.freebsd.org/D31885
malloc_domainset_aligned() requires that alignment is less than
page size. Fall back to other allocation methods, most likely
kmem_alloc_contig(), when malloc_aligned() cannot fullfill the driver
request.
Reported by: Loic F <loic.f@hardenedbsd.org>
Reviewed by: markj
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D32127
Before this device unit number match was coincidental and broke if I
disabled some CPU device(s). Aside of cosmetics, for some drivers
(may be considered broken) it caused talking to wrong CPUs.
Depending on hardware, NUMA nodes may match last level caches, or
they may be above them (AMD Zen 2/3) or below (Intel Xeon w/ SNC).
This information is provided by ACPI instead of CPUID, and it is
provided for each CPU individually instead of mask widths, but
this code should be able to properly handle all the above cases.
This change should immediately allow idle stealing in sched_ule(4)
to prefer load from NUMA-local CPUs to remote ones when the node
does not match LLC. Later we may think of how to better handle it
on sched_pickcpu() side.
MFC after: 1 month
This reverts commit 0f6829488e.
Also it changes the type of md_usr_fpu_save struct mdthread member
to void *, which is what uncovered this trouble. Now the save area
is untyped, but since it is hidden behind accessors, it is not too
significant. Since apparently there are consumers affected outside
the tree, this hack is better than one from the reverted revision.
PR: 258678
Reported by: cy
Reviewed by: cy, kevans, markj
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D32060
when compiling in amd64 kernel environment with -m32. This is a temporal
workaround for some future proper (but unclear) fix.
Reviewed by: jhb, markj
Tested by: pho
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D31954
This implementation is faster and doesn't modify the cpuset, so it lets
us avoid some unnecessary copying as well. No functional change
intended.
Reviewed by: cem, kib, jhb
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D32029
The file as is is the maze of #ifdef passages, all slightly different.
Divorcing i386 and amd64 version actually makes changing the code
easier, also no changes for i386 are planned.
Reviewed by: markj
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D31931
This is required since kernel text might be physically located
anywhere below 4G.
PR: 258432
Reported by: Taku YAMAMOTO <taku@tackymt.homeip.net>
Reviewed by: markj
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D31916
Do not use tab between type and variable name in local declarations.
Reviewed by: markj
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D31916
Move the common kernel function signatures from machine/reg.h to a new
sys/reg.h. This is in preperation for adding PT_GETREGSET to ptrace(2).
Reviewed by: imp, markj
Sponsored by: DARPA, AFRL (original work)
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D19830
Clang 13 produces the following warning for hammer_time_xen():
sys/x86/xen/pv.c:183:19: error: the pointer incremented by -2147483648 refers past the last possible element for an array in 64-bit address space containing 256-bit (32-byte) elements (max possible 576460752303423488 elements) [-Werror,-Warray-bounds]
(vm_paddr_t)start_info->modlist_paddr + KERNBASE;
^ ~~~~~~~~
sys/xen/interface/arch-x86/hvm/start_info.h:131:5: note: array 'modlist_paddr' declared here
uint64_t modlist_paddr; /* Physical address of an array of */
^
This is because the expression first casts start_info->modlist_paddr to
struct hvm_modlist_entry * (via vmpaddr_t), and *then* adds KERNBASE,
which is then interpreted as KERNBASE * sizeof(struct
hvm_modlist_entry).
Instead, parenthesize the addition to get the intended result, and cast
it to struct hvm_modlist_entry * afterwards. Also remove the cast to
vmpaddr_t since it is not necessary.
Reviewed by: royger
MFC after: 3 days
Differential Revision: https://reviews.freebsd.org/D31711
Add vDSO support for timekeeping devices that support the KVM/XEN
paravirtual clock API.
Also, expose, in the userspace-accessible '<machine/pvclock.h>',
definitions that will be needed by 'libc' to support
'VDSO_TH_ALGO_X86_PVCLK'.
Sponsored by: Juniper Networks, Inc.
Sponsored by: Klara, Inc.
Reviewed by: kib
Differential Revision: https://reviews.freebsd.org/D31418
Add support for the KVM paravirtual clock device.
Sponsored by: Juniper Networks, Inc.
Sponsored by: Klara, Inc.
Reviewed by: kib
Differential Revision: https://reviews.freebsd.org/D29733
Consolidate more hypervisor-agnostic functionality behind a new 'struct
pvclock' API.
This should also make it easier to subsequently add hypervisor-agnostic
vDSO timekeeping support.
Also, perform some clean-up:
- Remove 'pvclock_get_last_cycles()'; do not allow external access
to 'pvclock_last_systime' since this is not necessary.
- Consolidate/simplify wall and system time reading codepaths.
- Ensure correct ordering within wall and system time reading
codepaths via 'atomic(9)' and 'rdtsc_ordered()' rather than via
'rmb()'.
- Remove some extra newlines.
Sponsored by: Juniper Networks, Inc.
Sponsored by: Klara, Inc.
Reviewed by: kib
Differential Revision: https://reviews.freebsd.org/D31418
Add a variant of 'rdtsc()' that performs the ordered version of 'rdtsc'
appropriate for the invoking x86 variant.
Also, expose the 'lfence'-ed and 'mfence'-ed 'rdtsc()' variants needed
by 'rdtsc_ordered()' for general use.
Sponsored by: Juniper Networks, Inc.
Sponsored by: Klara, Inc.
Reviewed by: kib
Differential Revision: https://reviews.freebsd.org/D31416
At least Linux x86 ABI's does not use carry bit and expects that the dx register
is preserved. For this add a new sv_set_fork_retval hook and call it from cpu_fork().
Add a short comment about touching dx in x86_set_fork_retval(), for more details
see phab comments from kib@ and imp@.
Reviewed by: kib
Differential revision: https://reviews.freebsd.org/D31472
MFC after: 2 weeks
Sanitizer instrumentation of course cannot automatically update shadow
state when devices write to host memory. KMSAN thus hooks into busdma,
both to update shadow state after a device write, and to verify that the
kernel does not publish uninitalized bytes to devices.
To implement this, when KMSAN is configured, each dmamap embeds a memory
descriptor describing the region currently loaded into the map.
bus_dmamap_sync() uses the operation flags to determine whether to
validate the loaded region or to mark it as initialized in the shadow
map.
Note that in cases where the amount of data written is less than the
buffer size, the entire buffer is marked initialized even when it is
not. For example, if a NIC writes a 128B packet into a 2KB buffer, the
entire buffer will be marked initialized, but subsequent accesses past
the first 128 bytes are likely caused by bugs.
Reviewed by: kib
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D31338
Use this flag to indicate that busdma should allocate a map structure
even no bouncing is required to satisfy the tag's constraints. This
will be used for KMSAN.
Also fix a memory leak that can occur if the kernel fails to allocate
bounce pages in bounce_bus_dmamap_create().
Reviewed by: kib
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D31338
Interrupt and exception handlers must call kmsan_intr_enter() prior to
calling any C code. This is because the KMSAN runtime maintains some
TLS in order to track initialization state of function parameters and
return values across function calls. Then, to ensure that this state is
kept consistent in the face of asynchronous kernel-mode excpeptions, the
runtime uses a stack of TLS blocks, and kmsan_intr_enter() and
kmsan_intr_leave() push and pop that stack, respectively.
Use these functions in amd64 interrupt and exception handlers. Note
that handlers for user->kernel transitions need not be annotated.
Also ensure that trap frames pushed by the CPU and by handlers are
marked as initialized before they are used.
Reviewed by: kib
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D31467
These ones were unambiguous cases where the Foundation was the only
listed copyright holder (in the associated license block).
Sponsored by: The FreeBSD Foundation
KASAN and KCSAN implement interceptors for various primitive operations
that are not instrumented by the compiler. KMSAN requires them as well.
Rather than adding new cases for each sanitizer which requires
interceptors, implement the following protocol:
- When interceptor definitions are required, define
SAN_NEEDS_INTERCEPTORS and SANITIZER_INTERCEPTOR_PREFIX.
- In headers that declare functions which need to be intercepted by a
sanitizer runtime, use SANITIZER_INTERCEPTOR_PREFIX to provide
declarations.
- When SAN_RUNTIME is defined, do not redefine the names of intercepted
functions. This is typically the case in files which implement
sanitizer runtimes but is also needed in, for example, files which
define ifunc selectors for intercepted operations.
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation
There is no reason now why do we need to allocate trampoline page very
early in the boot process. The only requirement for the page is that
it is below 1M to be usable by the real mode during init. This can be
handled by vm_alloc_contig() when we do the startup.
Also assert that startup trampoline fits into single page. In principle
we can do multi-page allocation if needed, but it is not.
Move the alloc_ap_trampoline() function and the boot_address variable to
i386/mp_machdep.c. Keep existing mechanism of early alloc on i386.
Reviewed by: markj
Sponsored by: The FreeBSD Foundation
MFC after: 2 weeks
Differential revision: https://reviews.freebsd.org/D31343
Before this change my dual-Xeon(R) Gold 6242R always reported 3 levels
or topology (root, package/L3 and core/L2). But with SMT disabled
core/L2 matches thread, so additional topology level only causes more
traversal work. With this change SMT case is reported same as before,
while non-SMT is reported with only 2 much more simple levels.
MFC after: 2 weeks
xen_vector_callback_enabled is x86 specific and availability of
per-cpu event channel delivery differs on other architectures.
Introduce a new helper to check if there's support for per-cpu event
channel injection.
Submitted by: Elliott Mitchell <ehem+freebsd@m5p.com>
Reviewed by: royger
Differential Revision: https://reviews.freebsd.org/D29402
While x86 only register PV shutdown handler for PV guests. ARM guests
are always using HVM and requires the PV shutdown handler.
Submitted by: Elliott Mitchell <ehem+freebsd@m5p.com>
Reviewed by: royger
Differential Revision: https://reviews.freebsd.org/D29406
ARM guest is considered as HVM in Freebsd but they only support PV disk
(no emulation available).
Submitted by: Elliott Mitchell <ehem+freebsd@m5p.com>
Reviewed by: royger
Differential Revision: https://reviews.freebsd.org/D29403
ARM guest is considered as HVM but it only supports PV nics (no
emulation available).
Submitted by: Elliott Mitchell <ehem+freebsd@m5p.com>
Reviewed by: royger
Differential Revision: https://reviews.freebsd.org/D29405
Several of x86 enable/disable functions depend upon the xen*domain()
functions. As such the xen*domain() functions need to be declared
before machine/xen-os.h.
Officially declare direct inclusion of machine/xen/xen-os.h verboten as
such will break these functions/macros. Remove one such soon to be
broken inclusion.
Reviewed by: royger
Differential Revision: https://reviews.freebsd.org/D29811
Functions tend to get renamed and unless the developer is careful
often debugging messages are missed. As such using func is far
superior. Replace several instances of hard-coded function names.
Reviewed by: royger
Differential revision: https://reviews.freebsd.org/D29499
Since xen_intr_handle_t is meant to be an opaque handle and the only
use is retrieving the associated struct xenisrc *, directly use it as
the opaque handler.
Also add a wrapper function for converting the other direction. If some
other value becomes appropriate in the future, these two functions will
be the only spots needing modification.
Reviewed by: mhorne, royger
Differential Revision: https://reviews.freebsd.org/D29500
