The implementation of bus_dmamap_load_ma_triv currently calls
_bus_dmamap_load_phys on each page that is part of the passed in buffer.
Since each page is treated as an individual buffer, the resulting behaviour
is different from the behaviour of _bus_dmamap_load_buffer. This breaks
certain drivers, like Xen blkfront.
If an unmapped buffer of size 4096 that starts at offset 13 into the first
page is passed to the current _bus_dmamap_load_ma implementation (so the ma
array contains two pages), the result is that two segments are created, one
with a size of 4083 and the other with size 13 (because two independant
calls to _bus_dmamap_load_phys are performed, one for each physical page).
If the same is done with a mapped buffer and calling _bus_dmamap_load_buffer
the result is that only one segment is created, with a size of 4096.
This patch relegates the usage of bus_dmamap_load_ma_triv in x86 bounce
buffer code to drivers requesting BUS_DMA_KEEP_PG_OFFSET and implements
_bus_dmamap_load_ma so that it's behaviour is the same as the mapped version
(_bus_dmamap_load_buffer). This patch only modifies the x86 bounce buffer
code, other arches are left untouched.
Sponsored by: Citrix Systems R&D
Reviewed by: kib, jah (previous version)
MFC after: 2 weeks
Differential Revision: https://reviews.freebsd.org/D888
variable during mp_start() which is too late. Move this to mp_setmaxid()
where other architectures set it and move x86 assertions to MI code.
Reviewed by: kib (x86 part)
Fix two issues with the current event channel code, first ENABLED_SETSIZE is
not correctly defined and then using a BITSET to store the per-cpu masks is
not portable to other arches, since on arm32 the event channel arrays shared
with the hypervisor are of type uint64_t and not long. Partially restore the
previous code but switch the bit operations to use the recently introduced
xen_{set/clear/test}_bit versions.
Reviewed by: Julien Grall <julien.grall@citrix.com>
Sponsored by: Citrix Systems R&D
Differential Revision: https://reviews.freebsd.org/D4080
This will enable the elimination of a workaround in the USB driver that
artifically allocates buffers twice as big as they need to be (which
actually saves memory for very small buffers on the buggy platforms).
When deciding how to allocate a dma buffer, armv4, armv6, mips, and
x86/iommu all correctly check for the tag alignment <= maxsize as enabling
simple uma/malloc based allocation. Powerpc, sparc64, x86/bounce, and
arm64/bounce were all checking for alignment < maxsize; on those platforms
when alignment was equal to the max size it would fall back to page-based
allocators even for very small buffers.
This change makes all platforms use the <= check. It should be noted that
on all platforms other than arm[v6] and mips, this check is relying on
undocumented behavior in malloc(9) that if you allocate a block of a given
size it will be aligned to the next larger power-of-2 boundary. There is
nothing in the malloc(9) man page that makes that explicit promise (but the
busdma code has been relying on this behavior all along so I guess it works).
Arm and mips code uses the allocator in kern/subr_busdma_buffalloc.c, which
does explicitly implement this promise about size and alignment. Other
platforms probably should switch to the aligned allocator.
The new load_ma implementation can cause dereferences when used with
certain drivers, back it out until the reason is found:
Fatal trap 12: page fault while in kernel mode
cpuid = 11; apic id = 03
fault virtual address = 0x30
fault code = supervisor read data, page not present
instruction pointer = 0x20:0xffffffff808a2d22
stack pointer = 0x28:0xfffffe07cc737710
frame pointer = 0x28:0xfffffe07cc737790
code segment = base 0x0, limit 0xfffff, type 0x1b
= DPL 0, pres 1, long 1, def32 0, gran 1
processor eflags = interrupt enabled, resume, IOPL = 0
current process = 13 (g_down)
trap number = 12
panic: page fault
cpuid = 11
KDB: stack backtrace:
#0 0xffffffff80641647 at kdb_backtrace+0x67
#1 0xffffffff80606762 at vpanic+0x182
#2 0xffffffff806067e3 at panic+0x43
#3 0xffffffff8084eef1 at trap_fatal+0x351
#4 0xffffffff8084f0e4 at trap_pfault+0x1e4
#5 0xffffffff8084e82f at trap+0x4bf
#6 0xffffffff80830d57 at calltrap+0x8
#7 0xffffffff8063beab at _bus_dmamap_load_ccb+0x1fb
#8 0xffffffff8063bc51 at bus_dmamap_load_ccb+0x91
#9 0xffffffff8042dcad at ata_dmaload+0x11d
#10 0xffffffff8042df7e at ata_begin_transaction+0x7e
#11 0xffffffff8042c18e at ataaction+0x9ce
#12 0xffffffff802a220f at xpt_run_devq+0x5bf
#13 0xffffffff802a17ad at xpt_action_default+0x94d
#14 0xffffffff802c0024 at adastart+0x8b4
#15 0xffffffff802a2e93 at xpt_run_allocq+0x193
#16 0xffffffff802c0735 at adastrategy+0xf5
#17 0xffffffff80554206 at g_disk_start+0x426
Uptime: 2m29s
The implementation of bus_dmamap_load_ma_triv currently calls
_bus_dmamap_load_phys on each page that is part of the passed in buffer.
Since each page is treated as an individual buffer, the resulting behaviour
is different from the behaviour of _bus_dmamap_load_buffer. This breaks
certain drivers, like Xen blkfront.
If an unmapped buffer of size 4096 that starts at offset 13 into the first
page is passed to the current _bus_dmamap_load_ma implementation (so the ma
array contains two pages), the result is that two segments are created, one
with a size of 4083 and the other with size 13 (because two independant
calls to _bus_dmamap_load_phys are performed, one for each physical page).
If the same is done with a mapped buffer and calling _bus_dmamap_load_buffer
the result is that only one segment is created, with a size of 4096.
This patch relegates the usage of bus_dmamap_load_ma_triv in x86 bounce
buffer code to drivers requesting BUS_DMA_KEEP_PG_OFFSET and implements
_bus_dmamap_load_ma so that it's behaviour is the same as the mapped version
(_bus_dmamap_load_buffer). This patch only modifies the x86 bounce buffer
code, other arches are left untouched.
Reviewed by: kib, jah
Differential Revision: https://reviews.freebsd.org/D888
Sponsored by: Citrix Systems R&D
xen/hypervisor.h:
- Remove unused helpers: MULTI_update_va_mapping, is_initial_xendomain,
is_running_on_xen
- Remove unused define CONFIG_X86_PAE
- Remove unused variable xen_start_info: note that it's used inpcifront
which is not built at all
- Remove forward declaration of HYPERVISOR_crash
xen/xen-os.h:
- Remove unused define CONFIG_X86_PAE
- Drop unused helpers: test_and_clear_bit, clear_bit,
force_evtchn_callback
- Implement a generic version (based on ofed/include/linux/bitops.h) of
set_bit and test_bit and prefix them by xen_ to avoid any use by other
code than Xen. Note that It would be worth to investigate a generic
implementation in FreeBSD.
- Replace barrier() by __compiler_membar()
- Replace cpu_relax() by cpu_spinwait(): it's exactly the same as rep;nop
= pause
xen/xen_intr.h:
- Move the prototype of xen_intr_handle_upcall in it: Use by all the
platform
x86/xen/xen_intr.c:
- Use BITSET* for the enabledbits: Avoid to use custom helpers
- test_bit/set_bit has been renamed to xen_test_bit/xen_set_bit
- Don't export the variable xen_intr_pcpu
dev/xen/blkback/blkback.c:
- Fix the string format when XBB_DEBUG is enabled: host_addr is typed
uint64_t
dev/xen/balloon/balloon.c:
- Remove set but not used variable
- Use the correct type for frame_list: xen_pfn_t represents the frame
number on any architecture
dev/xen/control/control.c:
- Return BUS_PROBE_WILDCARD in xs_probe: Returning 0 in a probe callback
means the driver can handle this device. If by any chance xenstore is the
first driver, every new device with the driver is unset will use
xenstore.
dev/xen/grant-table/grant_table.c:
- Remove unused cmpxchg
- Drop unused include opt_pmap.h: Doesn't exist on ARM64 and it doesn't
contain anything required for the code on x86
dev/xen/netfront/netfront.c:
- Use the correct type for rx_pfn_array: xen_pfn_t represents the frame
number on any architecture
dev/xen/netback/netback.c:
- Use the correct type for gmfn: xen_pfn_t represents the frame number on
any architecture
dev/xen/xenstore/xenstore.c:
- Return BUS_PROBE_WILDCARD in xctrl_probe: Returning 0 in a probe callback
means the driver can handle this device. If by any chance xenstore is the
first driver, every new device with the driver is unset will use xenstore.
Note that with the changes, x86/include/xen/xen-os.h doesn't contain anymore
arch-specific code. Although, a new series will add some helpers that differ
between x86 and ARM64, so I've kept the headers for now.
Submitted by: Julien Grall <julien.grall@citrix.com>
Reviewed by: royger
Differential Revision: https://reviews.freebsd.org/D3921
Sponsored by: Citrix Systems R&D
amd64 and i386 platform code contain very similar xen/xen-os.h
The only differences are:
- Functions/variables/types which were unused in i386/xen/xen-os.h:
* xen_xchg
* __xchg_dummy
* __xg
* __xchg
* atomic_t
* atomic_inc
* rdtscll
The functions/variables/types unused in xen-os.h can be dropped and there
is no more differences betwen amd64 and i386.
The new header is placed in x86/include/xen and each platform will have
dummy headers include x86/xen/*.h. This is to be able to include
machine/xen/*.h in the PV drivers.
Submitted by: Julien Grall <julien.grall@citrix.com>
Reviewed by: royger
Differential Revision: https://reviews.freebsd.org/D3880
Sponsored by: Citrix Systems R&D
When the system has more than a single PCI domain, the bus numbers
are not unique, thus they cannot be used for "pci" device numbering.
Change bus numbers to -1 (i.e. to-be-determined automatically)
wherever the code did not care about domains.
Reviewed by: jhb
Obtained from: Semihalf
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D3406
that was recently added for Lenovo laptops.
This is a prime candidate for conversion into a table and also
checking other fields like "product".
Tested:
* ASUS UX31E
running thread.
It is currently implemented only on amd64 and i386; on these
architectures, it is implemented by raising an NMI on the CPU on which
the target thread is currently running. Unlike stack_save_td(), it may
fail, for example if the thread is running in user mode.
This change also modifies the kern.proc.kstack sysctl to use this function,
so that stacks of running threads are shown in the output of "procstat -kk".
This is handy for debugging threads that are stuck in a busy loop.
Reviewed by: bdrewery, jhb, kib
Sponsored by: EMC / Isilon Storage Division
Differential Revision: https://reviews.freebsd.org/D3256
since on amd64 the first argument to a function is generally not on the
stack.
Revert an old DTrace bug fix to some code that assumed that
sizeof(struct amd64_frame) == 16.
Reviewed by: jhb, kib
Sponsored by: EMC / Isilon Storage Division
Differential Revision: https://reviews.freebsd.org/D3255
Add a check to preload_search_info to make sure mod is set. Most of the
callers of preload_search_info don't check that the mod parameter is
set, which can cause page faults. While at it, remove some now unnecessary
checks before calling preload_search_info.
Sponsored by: Citrix Systems R&D
Reviewed by: kib
Differential Revision: https://reviews.freebsd.org/D3440
Introduce two new loader tunnables that can be used to disable PV disks and
PV nics at boot time. They default to 0 and should be set to 1 (or any
number different than 0) in order to disable the PV devices:
hw.xen.disable_pv_disks=1
hw.xen.disable_pv_nics=1
In /boot/loader.conf will disable both PV disks and nics.
Sponsored by: Citrix Systems R&D
Tested by: Karl Pielorz <kpielorz_lst@tdx.co.uk>
MFC after: 1 week
believe that the bug only affects mobile CPUs, at least I did not see
other reports, but it is impossible to detect it in madt_setup_local().
While there, reduce duplication in the information strings printed
when x2APIC is auto-disabled, and do not print the line when user
manually override the setting.
Tested and reviewed by: royger (previous version)
Sponsored by: The FreeBSD Foundation
This allows two things:
1. Sync'ing bounced maps in non-sleepable contexts. The physcopy* calls previously used could sleep on sf_buf operations in some cases.
2. Sync'ing user buffers outside the context of the owning process
Approved by: kib (mentor)
frame buffers and memory mapped UARTs.
1. Delay calling cninit() until after pmap_bootstrap(). This makes
sure we have PMAP initialized enough to add translations. Keep
kdb_init() after cninit() so that we have console when we need
to break into the debugger on boot.
2. Unfortunately, the ATPIC code had be moved as well so as to
avoid a spurious trap #30. The reason for which is not known
at this time.
3. In pmap_mapdev_attr(), when we need to map a device prior to the
VM system being initialized, use virtual_avail as the KVA to map
the device at. In particular, avoid using the direct map on amd64
because we can't demote by virtue of not being able to allocate
yet. Keep track of the translation.
Re-use the translation after the VM has been initialized to not
waste KVA and to satisfy the assumption in uart(4) that the handle
returned for the low-level console is the same as later returned
when the device is probed and attached.
4. In pmap_unmapdev() remove the mapping from the table when called
pre-init. Otherwise keep the mapping. During bus probe and attach
device resources are mapped and unmapped multiple times, which
would have us destroy the mapping used by the low-level console.
5. In pmap_init(), set pmap_initialized to signal that we're not
pre-init anymore. On amd64, bring the direct map in sync with the
translations created at that time.
6. Implement bus_space_map() and bus_space_unmap() for real: when
the tag corresponds to memory space, call the corresponding
pmap_mapdev() and pmap_unmapdev() functions to construct and
actual handle.
7. In efifb.c and vt_vga.c, remove the crutches and hacks and simply
call pmap_mapdev_attr() or bus_space_map() as desired.
Notes:
1. uart(4) already used bus_space_map() during low-level console
setup but since serial ports have traditionally been I/O port
based, the lack of a proper implementation for said function
was not a problem. It has always supported memory mapped UARTs
for low-level consoles by setting hw.uart.console accordingly.
2. The use of the direct map on amd64 without setting caching
attributes has been a bigger problem than previously thought.
This change has the fortunate (and unexpected) side-effect of
fixing various EFI frame buffer problems (though not all).
PR: 191564, 194952
Special thanks to:
1. XipLink, Inc -- generously donated an Intel Bay Trail E3800
based eval board (ADLE3800PC).
2. The FreeBSD Foundation, in particular emaste@ -- for UEFI
support in general and testing.
3. Everyone who tested the proposed for PR 191564.
4. jhb@ and kib@ for being a soundboard and applying a clue bat
if so needed.
single ICR MSR write. This is in contrast with the xAPIC mode, where
we must read current ICR value, do bit fiddling and perform two 32-bit
register writes. As a consequence, there is no need to disable
interrupts around ICR value calculation and write.
Note that typical users of ipi_raw() and ipi_vectored() take spinlock,
which already disables interrupts. For them, the change removes
unneeded CLI and POPFL/Q instructions.
Tested by: pho
Sponsored by: The FreeBSD Foundation
MFC after: 2 weeks
initial thread stack is not adjusted by the tunable, the stack is
allocated too early to get access to the kernel environment. See
TD0_KSTACK_PAGES for the thread0 stack sizing on i386.
The tunable was tested on x86 only. From the visual inspection, it
seems that it might work on arm and powerpc. The arm
USPACE_SVC_STACK_TOP and powerpc USPACE macros seems to be already
incorrect for the threads with non-default kstack size. I only
changed the macros to use variable instead of constant, since I cannot
test.
On arm64, mips and sparc64, some static data structures are sized by
KSTACK_PAGES, so the tunable is disabled.
Sponsored by: The FreeBSD Foundation
MFC after: 2 week
The expected semantic is to have misc. data, e.g. CPU bitmaps, visible
in the BSP after smp_started is written by the last started AP, which
formally requires acquire barrier on the load. The change is mostly
nop due to the ordered behaviour of the x86 CPUs.
Reviewed by: alc
Sponsored by: The FreeBSD Foundation
MFC after: 2 weeks
use vtophys() directly instead of vtomach() and retire the no-longer-used
headers <machine/xenfunc.h> and <machine/xenvar.h>.
Reported by: bde (stale bits in <machine/xenfunc.h>)
Reviewed by: royger (earlier version)
Differential Revision: https://reviews.freebsd.org/D3266
reported, on APs. We already did this on BSP.
Otherwise, the userspace software which depends on the features
reported by the high CPUID levels is misbehaving. In particular, AVX
detection is non-functional, depending on which CPU thread happens to
execute when doing CPUID. Another victim is the libthr signal
handlers interposer, which needs to save full FPU extended state.
Reported and tested by: Andre Meiser <ortadur@web.de>
Sponsored by: The FreeBSD Foundation
MFC after: 2 weeks
If KSTACK_PAGES was changed to anything alse than the default,
the value from param.h was taken instead in some places and
the value from KENRCONF in some others. This resulted in
inconsistency which caused corruption in SMP envorinment.
Ensure all places where KSTACK_PAGES are used the opt_kstack_pages.h
is included.
The file opt_kstack_pages.h could not be included in param.h
because was breaking the toolchain compilation.
Reviewed by: kib
Obtained from: Semihalf
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D3094
booting on a PC with CMOS clock set to a year before 2000.
This uses 1980 (instead of 1970 as in the initial patch) as pivot year as
suggested by imp in the PR followup.
PR: 195703
Submitted by: cs@soi.spb.ru
Reviewed by: imp
MFC after: 1 weeks
obtain the thread %fs and %gs bases. Add x86 PT_SETFSBASE and
PT_SETGSBASE requests to set the bases from debuggers. The set
requests, similarly to the sysarch({I386,AMD64}_SET_FSBASE),
override the corresponding segment registers.
The main purpose of the operations is to retrieve and modify the tcb
address for debuggee.
Sponsored by: The FreeBSD Foundation
MFC after: 2 weeks
and related data structures. Contexts attach requests initiators to
domains. There is still 1:1 correspondence between contexts and
domains on the running system, since only busdma currently allocates
them, using dmar_get_ctx_for_dev().
Large part of the change is formal rename of the ctx to domain, but
patch also reworks the context allocation and free to allow for
independent domain creation.
The helper dmar_move_ctx_to_domain() is introduced for future use, to
reassign request initiator from one domain to another. The hard issue
which is not yet resolved with the context move is proper handling (or
reserving) RMRR entries in the destination domain as required by ACPI
DMAR table for moved context.
Tested by: pho
Sponsored by: The FreeBSD Foundation
BIOS has been seen to include such entries even though the relevant specs
require that X2APIC entries only be used for CPUs with an APIC ID >= 255.
This was tested on a system with "plain" local APIC entries in the MADT
to ensure no regressions, but it has not yet been tested on a system with
X2APIC entries in the MADT. Currently such systems do not boot at all,
and with this change they might now boot correctly.
Differential Revision: https://reviews.freebsd.org/D2521
Reviewed by: kib
MFC after: 2 weeks
rev. 55. The modern CPUs cache and TLB descriptions looked quite
questionable without the update, e.g. Haswell i7 4770S reported:
Data TLB: 4 KB pages, 4-way set associative, 64 entries
L2 cache: 256 kbytes, 8-way associative, 64 bytes/line
After the update, the report is:
Data TLB: 1 GByte pages, 4-way set associative, 4 entries
Data TLB: 4 KB pages, 4-way set associative, 64 entries
Instruction TLB: 2M/4M pages, fully associative, 8 entries
Instruction TLB: 4KByte pages, 8-way set associative, 64 entries
64-Byte prefetching
Shared 2nd-Level TLB: 4 KByte/2MByte pages, 8-way associative, 1024 entries
L2 cache: 256 kbytes, 8-way associative, 64 bytes/line
Some tags were apparently removed from the table 3-21, Vol. 2A. Keep
them around, but add a comment stating the removal.
Update the format line for cpu_stdext_feature according to the bits
from the SDM rev.55. It appears that Haswells do not store %cs and
%ds values in the FPU save area.
Store content of the %ecx register from the CPUID leaf 0x7
subleaf 0 as cpu_stdext_feature2 and print defined bits from it,
again acording to SDM rev. 55.
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
buildkernel run.
Some of them were write-only under some kernel options, e.g. variables
keeping values only used by CTR() macros. It costs nothing to the
code readability and correctness to eliminate the warnings in those
cases too by removing the local cached values used only for
single-access.
Review: https://reviews.freebsd.org/D2665
Reviewed by: rodrigc
Looked at by: bjk
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
queue is started, not relying on the interrupt remaping method to
happen. Also disable interrupts when shooting down the queue.
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
years for head. However, it is continuously misused as the mpsafe argument
for callout_init(9). Deprecate the flag and clean up callout_init() calls
to make them more consistent.
Differential Revision: https://reviews.freebsd.org/D2613
Reviewed by: jhb
MFC after: 2 weeks