Additionally doing things conditionally upon smp_processor_id()
being zero is generally a bad idea, as this means CPU 0 cannot
be offlined and brought back online later again.
While there may be other places where this is done, I think adding
more of those should be avoided so that some day SMP can really
become "symmetrical".
Signed-off-by: Jan Beulich <jbeulich@novell.com>
Cc: Cyrill Gorcunov <gorcunov@gmail.com>
LKML-Reference: <4D525C7E0200007800030EE1@vpn.id2.novell.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Commit 4c321ff8 (x86: Replace cpu_2_logical_apicid[] with early
percpu variable) and following changes introduced and used
x86_cpu_to_logical_apicid percpu variable. It was declared and
defined inside CONFIG_SMP && CONFIG_X86_32 but if
CONFIG_X86_UP_APIC is set UP configuration makes use of it and
build fails.
Fix it by declaring and defining it inside CONFIG_X86_LOCAL_APIC
&& CONFIG_X86_32.
Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: Ingo Molnar <mingo@elte.hu>
Cc: eric.dumazet@gmail.com
Cc: yinghai@kernel.org
Cc: brgerst@gmail.com
Cc: gorcunov@gmail.com
Cc: penberg@kernel.org
Cc: shaohui.zheng@intel.com
Cc: rientjes@google.com
LKML-Reference: <20110128162248.GA25746@htj.dyndns.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
The mapping between cpu/apicid and node is done via
apicid_to_node[] on 64bit and apicid_2_node[] +
apic->x86_32_numa_cpu_node() on 32bit. This difference makes it
difficult to further unify 32 and 64bit NUMA handling.
This patch unifies it by replacing both apicid_to_node[] and
apicid_2_node[] with __apicid_to_node[] array, which is accessed
by two accessors - set_apicid_to_node() and numa_cpu_node(). On
64bit, numa_cpu_node() always consults __apicid_to_node[]
directly while 32bit goes through apic->numa_cpu_node() method
to allow apic implementations to override it.
srat_detect_node() for amd cpus contains workaround for broken
NUMA configuration which assumes relationship between APIC ID,
HT node ID and NUMA topology. Leave it to access
__apicid_to_node[] directly as mapping through CPU might result
in undesirable behavior change. The comment is reformatted and
updated to note the ugliness.
Signed-off-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Pekka Enberg <penberg@kernel.org>
Cc: eric.dumazet@gmail.com
Cc: yinghai@kernel.org
Cc: brgerst@gmail.com
Cc: gorcunov@gmail.com
Cc: shaohui.zheng@intel.com
Cc: rientjes@google.com
LKML-Reference: <1295789862-25482-14-git-send-email-tj@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: David Rientjes <rientjes@google.com>
apic->apicid_to_node() is 32bit specific apic operation which
determines NUMA node for a CPU. Depending on the APIC
implementation, it can be easier to determine NUMA node from
either physical or logical apicid. Currently,
->apicid_to_node() takes @logical_apicid and calls
hard_smp_processor_id() if the physical apicid is needed.
This prevents NUMA mapping from being queried from a different
CPU, which in turn makes it impossible to initialize NUMA
mapping before SMP bringup.
This patch replaces apic->apicid_to_node() with
->x86_32_numa_cpu_node() which takes @cpu, from which both
logical and physical apicids can easily be determined. While at
it, drop duplicate implementations from bigsmp_32 and summit_32,
and use the default one.
Signed-off-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Pekka Enberg <penberg@kernel.org>
Cc: eric.dumazet@gmail.com
Cc: yinghai@kernel.org
Cc: brgerst@gmail.com
Cc: gorcunov@gmail.com
Cc: shaohui.zheng@intel.com
Cc: rientjes@google.com
LKML-Reference: <1295789862-25482-13-git-send-email-tj@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
On x86_32, the mapping between cpu and logical apic ID differs
depending on the specific apic implementation in use. The
mapping is initialized while bringing up CPUs; however, this
makes early inits ignore memory topology.
Add a x86_32 specific apic->x86_32_early_logical_apicid() which
is called early during boot to query the mapping. The mapping
is later verified against the result of init_apic_ldr(). The
method is allowed to return BAD_APICID if it can't be determined
early.
noop variant which always returns BAD_APICID is implemented and
added to all x86_32 apic implementations.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: eric.dumazet@gmail.com
Cc: yinghai@kernel.org
Cc: brgerst@gmail.com
Cc: gorcunov@gmail.com
Cc: penberg@kernel.org
Cc: shaohui.zheng@intel.com
Cc: rientjes@google.com
LKML-Reference: <1295789862-25482-8-git-send-email-tj@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Currently, cpu -> logical apic id translation is done by
apic->cpu_to_logical_apicid() callback which may or may not use
x86_cpu_to_logical_apicid. This is unnecessary as it should
always equal logical_smp_processor_id() which is known early
during CPU bring up.
Initialize x86_cpu_to_logical_apicid after apic->init_apic_ldr()
in setup_local_APIC() and always use x86_cpu_to_logical_apicid
for cpu -> logical apic id mapping.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: eric.dumazet@gmail.com
Cc: yinghai@kernel.org
Cc: brgerst@gmail.com
Cc: gorcunov@gmail.com
Cc: penberg@kernel.org
Cc: shaohui.zheng@intel.com
Cc: rientjes@google.com
LKML-Reference: <1295789862-25482-6-git-send-email-tj@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Unlike x86_64, on x86_32, the mapping from cpu to logical apicid
may vary depending on apic in use. cpu_2_logical_apicid[] array
is used for this mapping. Replace it with early percpu variable
x86_cpu_to_logical_apicid to make it better aligned with other
mappings.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: eric.dumazet@gmail.com
Cc: yinghai@kernel.org
Cc: brgerst@gmail.com
Cc: gorcunov@gmail.com
Cc: penberg@kernel.org
Cc: shaohui.zheng@intel.com
Cc: rientjes@google.com
LKML-Reference: <1295789862-25482-5-git-send-email-tj@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
x86: Fix Moorestown VRTC fixmap placement
x86/gpio: Implement x86 gpio_to_irq convert function
x86, UV: Fix APICID shift for Westmere processors
x86: Use PCI method for enabling AMD extended config space before MSR method
x86: tsc: Prevent delayed init if initial tsc calibration failed
x86, lapic-timer: Increase the max_delta to 31 bits
x86: Fix sparse non-ANSI function warnings in smpboot.c
x86, numa: Fix CONFIG_DEBUG_PER_CPU_MAPS without NUMA emulation
x86, AMD, PCI: Add AMD northbridge PCI device id for CPU families 12h and 14h
x86, numa: Fix cpu to node mapping for sparse node ids
x86, numa: Fake node-to-cpumask for NUMA emulation
x86, numa: Fake apicid and pxm mappings for NUMA emulation
x86, numa: Avoid compiling NUMA emulation functions without CONFIG_NUMA_EMU
x86, numa: Reduce minimum fake node size to 32M
Fix up trivial conflict in arch/x86/kernel/apic/x2apic_uv_x.c
* 'stable/generic' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
xen: HVM X2APIC support
apic: Move hypervisor detection of x2apic to hypervisor.h
Latest atom socs(penwell) does not have hpet timer.
As their local APIC timer is clocked at 400KHZ, and the current
code limit their Initial Counter register to 23 bits, they
cannot sleep more than 1.34 seconds which leads to ~2 spurious
wakeup per second (1 per thread)
These SOCs support 32bit timer so we change the max_delta to at
least 31bits. So we can at least sleep for 300 seconds.
We could not find any previous chip errata where lapic would
only have 23 bit precision As powertop is suggesting to activate
HPET to "sleep longer", this could mean this problem is already
known.
Problem is here since very first implementation of lapic timer
as a clock event e9e2cdb [PATCH] clockevents: i386 drivers.
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Pierre Tardy <pierre.tardy@intel.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Arjan van de Ven <arjan@infradead.org>
Cc: Adrian Bunk <bunk@stusta.de>
Cc: H. Peter Anvin <hpa@linux.intel.com>
Cc: john stultz <johnstul@us.ibm.com>
Cc: Roman Zippel <zippel@linux-m68k.org>
Cc: Andi Kleen <ak@suse.de>
LKML-Reference: <1294327409-19426-1-git-send-email-pierre.tardy@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
* 'for-2.6.38' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu: (30 commits)
gameport: use this_cpu_read instead of lookup
x86: udelay: Use this_cpu_read to avoid address calculation
x86: Use this_cpu_inc_return for nmi counter
x86: Replace uses of current_cpu_data with this_cpu ops
x86: Use this_cpu_ops to optimize code
vmstat: User per cpu atomics to avoid interrupt disable / enable
irq_work: Use per cpu atomics instead of regular atomics
cpuops: Use cmpxchg for xchg to avoid lock semantics
x86: this_cpu_cmpxchg and this_cpu_xchg operations
percpu: Generic this_cpu_cmpxchg() and this_cpu_xchg support
percpu,x86: relocate this_cpu_add_return() and friends
connector: Use this_cpu operations
xen: Use this_cpu_inc_return
taskstats: Use this_cpu_ops
random: Use this_cpu_inc_return
fs: Use this_cpu_inc_return in buffer.c
highmem: Use this_cpu_xx_return() operations
vmstat: Use this_cpu_inc_return for vm statistics
x86: Support for this_cpu_add, sub, dec, inc_return
percpu: Generic support for this_cpu_add, sub, dec, inc_return
...
Fixed up conflicts: in arch/x86/kernel/{apic/nmi.c, apic/x2apic_uv_x.c, process.c}
as per Tejun.
Then we can reuse it for Xen later.
Acked-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Acked-by: Avi Kivity <avi@redhat.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Conflicts:
arch/x86/include/asm/io_apic.h
Merge reason: Resolve the conflict, update to a more recent -rc base
Signed-off-by: Ingo Molnar <mingo@elte.hu>
* 'x86-apic-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
x86: Fix APIC ID sizing bug on larger systems, clean up MAX_APICS confusion
x86, acpi: Parse all SRAT cpu entries even above the cpu number limitation
x86, acpi: Add MAX_LOCAL_APIC for 32bit
x86: io_apic: Split setup_ioapic_ids_from_mpc()
x86: io_apic: Fix CONFIG_X86_IO_APIC=n breakage
x86: apic: Move probe_nr_irqs_gsi() into ioapic_init_mappings()
x86: Allow platforms to force enable apic
Replace all uses of current_cpu_data with this_cpu operations on the
per cpu structure cpu_info. The scala accesses are replaced with the
matching this_cpu ops which results in smaller and more efficient
code.
In the long run, it might be a good idea to remove cpu_data() macro
too and use per_cpu macro directly.
tj: updated description
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Ingo Molnar <mingo@elte.hu>
Acked-by: H. Peter Anvin <hpa@zytor.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
We should use MAX_LOCAL_APIC for max apic ids and MAX_APICS as number
of local apics.
Also apic_version[] array should use MAX_LOCAL_APICs.
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
LKML-Reference: <4D0AD464.2020408@kernel.org>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Interrupt-remapping gets enabled very early in the boot, as it determines the
apic mode that the processor can use. And the current code enables the vt-d
fault handling before the setup_local_APIC(). And hence the APIC LDR registers
and data structure in the memory may not be initialized. So the vt-d fault
handling in logical xapic/x2apic modes were broken.
Fix this by enabling the vt-d fault handling in the end_local_APIC_setup()
A cleaner fix of enabling fault handling while enabling intr-remapping
will be addressed for v2.6.38. [ Enabling intr-remapping determines the
usage of x2apic mode and the apic mode determines the fault-handling
configuration. ]
Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
LKML-Reference: <20101201062244.541996375@intel.com>
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: stable@kernel.org [v2.6.32+]
Acked-by: Chris Wright <chrisw@sous-sol.org>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
setup_local_APIC() is used to setup local APIC early during CPU
initialization and already assumes that preemption is disabled on
entry. However, The function unnecessarily disables and enables
preemption and uses smp_processor_id() multiple times in and out of
the nested preemption disabled section. This gives the wrong
impression that the function might be able to handle being called with
preemption enabled and/or migrated to another processor in the middle.
Make it clear that the function is always called with preemption
disabled, drop the confusing preemption disable block and call
smp_processor_id() once at the beginning of the function.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Cyrill Gorcunov <gorcunov@gmail.com>
Reviewed-by: Pekka Enberg <penberg@kernel.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: brgerst@gmail.com
LKML-Reference: <4D00B3B9.7060702@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
If x2apic is preenabled and used by the kernel, we don't need to map
the lapic address. That mapping will never be used.
So just skip that in register_lapic_address()
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
LKML-Reference: <4CFDF69C.9070501@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Remove the printk as well, we don't want to print when nothing
changed. We print in register_lapic_address() already.
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
LKML-Reference: <4CFDF68A.7020902@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
It is almost the same as smp_register_lapic_addr(). We just need to
let smp_read_mpc() call smp_register_lapic_addr() when early==1.
Add the apic_printk to smp_register_lapic_address()
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
LKML-Reference: <4CFDF681.3030509@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
They are the same, move the common function to apic.c to allow
further cleanups.
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Len Brown <lenb@kernel.org>
LKML-Reference: <4CFDF675.4060305@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reason: apic cleanup series depends on x86/apic, x86/amd-nb x86/platform
Conflicts:
arch/x86/include/asm/io_apic.h
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Now that the bulk of the old nmi_watchdog is gone, remove all
the stub variables and hooks associated with it.
This touches lots of files mainly because of how the io_apic
nmi_watchdog was implemented. Now that the io_apic nmi_watchdog
is forever gone, remove all its fingers.
Most of this code was not being exercised by virtue of
nmi_watchdog != NMI_IO_APIC, so there shouldn't be anything to
risky here.
Signed-off-by: Don Zickus <dzickus@redhat.com>
Cc: fweisbec@gmail.com
Cc: gorcunov@openvz.org
LKML-Reference: <1289578944-28564-3-git-send-email-dzickus@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This improves error messages in case the BIOS was setting up
wrong LVT offsets.
Signed-off-by: Robert Richter <robert.richter@amd.com>
Acked-by: Borislav Petkov <borislav.petkov@amd.com>
LKML-Reference: <1288015419-29543-6-git-send-email-robert.richter@amd.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Some embedded x86 platforms don't setup the APIC in the
BIOS/bootloader and would be forced to add "lapic" on the kernel
command line. That's a bit akward.
Split out the force enable code from detect_init_APIC() and allow
platform code to call it from the platform setup. That avoids the
command line parameter and possible replication of the MSR dance in
the force enable code.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
LKML-Reference: <1287510389-8388-1-git-send-email-dirk.brandewie@gmail.com>
Signed-off-by: Dirk Brandewie <dirk.j.brandewie@intel.com>
We want the BIOS to setup the EILVT APIC registers. The offsets
were hardcoded and BIOS settings were overwritten by the OS.
Now, the subsystems for MCE threshold and IBS determine the LVT
offset from the registers the BIOS has setup. If the BIOS setup
is buggy on a family 10h system, a workaround enables IBS. If
the OS determines an invalid register setup, a "[Firmware Bug]:
" error message is reported.
We need this change also for upcomming cpu families.
Signed-off-by: Robert Richter <robert.richter@amd.com>
LKML-Reference: <1286360874-1471-3-git-send-email-robert.richter@amd.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This patch implements checks for the availability of LVT entries
(APIC500-530) and reserves it if used. The check becomes
necessary since we want to let the BIOS provide the LVT offsets.
The offsets should be determined by the subsystems using it
like those for MCE threshold or IBS. On K8 only offset 0
(APIC500) and MCE interrupts are supported. Beginning with
family 10h at least 4 offsets are available.
Since offsets must be consistent for all cores, we keep track of
the LVT offsets in software and reserve the offset for the same
vector also to be used on other cores. An offset is freed by
setting the entry to APIC_EILVT_MASKED.
If the BIOS is right, there should be no conflicts. Otherwise a
"[Firmware Bug]: ..." error message is generated. However, if
software does not properly determines the offsets, it is not
necessarily a BIOS bug.
Signed-off-by: Robert Richter <robert.richter@amd.com>
LKML-Reference: <1286360874-1471-2-git-send-email-robert.richter@amd.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Move enable_IR_x2apic() inside the default_setup_apic_routing(),
and for SMP platforms, move the default_setup_apic_routing() after
smp_sanity_check(). This cleans up the code that tries to avoid multiple
calls to default_setup_apic_routing() when smp_sanity_check() fails (which
goes through the APIC_init_uniprocessor() path).
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
LKML-Reference: <20100827181049.173087246@sbsiddha-MOBL3.sc.intel.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
* 'x86/urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
x86, asm: Use a lower case name for the end macro in atomic64_386_32.S
x86, asm: Refactor atomic64_386_32.S to support old binutils and be cleaner
x86: Document __phys_reloc_hide() usage in __pa_symbol()
x86, apic: Map the local apic when parsing the MP table.
This fixes a regression in 2.6.35 from 2.6.34, that is
present for select models of Intel cpus when people are
using an MP table.
The commit cf7500c0ea
"x86, ioapic: In mpparse use mp_register_ioapic" started
calling mp_register_ioapic from MP_ioapic_info. An extremely
simple change that was obviously correct. Unfortunately
mp_register_ioapic did just a little more than the previous
hand crafted code and so we gained this call path.
The problem call path is:
MP_ioapic_info()
mp_register_ioapic()
io_apic_unique_id()
io_apic_get_unique_id()
get_physical_broadcast()
modern_apic()
lapic_get_version()
apic_read(APIC_LVR)
Which turned out to be a problem because the local apic
was not mapped, at that point, unlike the similar point
in the ACPI parsing code.
This problem is fixed by mapping the local apic when
parsing the mptable as soon as we reasonably can.
Looking at the number of places we setup the fixmap for
the local apic, I see some serious simplification opportunities.
For the moment except for not duplicating the setting up of the
fixmap in init_apic_mappings, I have not acted on them.
The regression from 2.6.34 is tracked in bug
https://bugzilla.kernel.org/show_bug.cgi?id=16173
Cc: <stable@kernel.org> 2.6.35
Reported-by: David Hill <hilld@binarystorm.net>
Reported-by: Tvrtko Ursulin <tvrtko.ursulin@sophos.com>
Tested-by: Tvrtko Ursulin <tvrtko.ursulin@sophos.com>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
LKML-Reference: <m1eiee86jg.fsf_-_@fess.ebiederm.org>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Found one x2apic system kexec loop test failed
when CONFIG_NMI_WATCHDOG=y (old) or CONFIG_LOCKUP_DETECTOR=y (current tip)
first kernel can kexec second kernel, but second kernel can not kexec third one.
it can be duplicated on another system with BIOS preenabled x2apic.
First kernel can not kexec second kernel.
It turns out, when kernel boot with pre-enabled x2apic, it will not execute
disable_local_APIC on shutdown path.
when init_apic_mappings() is called in setup_arch, it will skip setting of
apic_phys when x2apic_mode is set. ( x2apic_mode is much early check_x2apic())
Then later, disable_local_APIC() will bail out early because !apic_phys.
So check !x2apic_mode in x2apic_mode in disable_local_APIC with !apic_phys.
another solution could be updating init_apic_mappings() to set apic_phys even
for preenabled x2apic system. Actually even for x2apic system, that lapic
address is mapped already in early stage.
BTW: is there any x2apic preenabled system with apicid of boot cpu > 255?
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
LKML-Reference: <4C3EB22B.3000701@kernel.org>
Acked-by: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: stable@kernel.org
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
When the SMP kernel decides to crash_kexec() the local APICs may have
pending interrupts in their vector tables.
The setup routine for the local APIC has a deficient mechanism for
clearing these interrupts, it only handles interrupts that has already
been dispatched to the local core for servicing (the ISR register) safely,
it doesn't consider lower prioritized queued interrupts stored in the IRR
register.
If you have more than one pending interrupt within the same 32 bit word in
the LAPIC vector table registers you may find yourself entering the IO
APIC setup with pending interrupts left in the LAPIC. This is a situation
for wich the IO APIC setup is not prepared. Depending of what/which
interrupt vector/vectors are stuck in the APIC tables your system may show
various degrees of malfunctioning. That was the reason why the
check_timer() failed in our system, the timer interrupts was blocked by
pending interrupts from the old kernel when routed trough the IO APIC.
Additional comment from Jiri Bohac:
==============
If this should go into stable release,
I'd add some kind of limit on the number of iterations, just to be safe from
hard to debug lock-ups:
+if (loops++ > MAX_LOOPS) {
+ printk("LAPIC pending clean-up")
+ break;
+}
while (queued);
with MAX_LOOPS something like 1E9 this would leave plenty of time for the
pending IRQs to be cleared and would and still cause at most a second of delay
if the loop were to lock-up for whatever reason.
[trenn@suse.de:
V2: Use tsc if avail to bail out after 1 sec due to possible virtual
apic_read calls which may take rather long (suggested by: Avi Kivity
<avi@redhat.com>) If no tsc is available bail out quickly after
cpu_khz, if we broke out too early and still have irqs pending (which
should never happen?) we still get a WARN_ON...
V3: - Fixed indentation -> checkpatch clean
- max_loops must be signed
V4: - Fix typo, mixed up tsc and ntsc in first rdtscll() call
V5: Adjust WARN_ON() condition to also catch error in cpu_has_tsc case]
Cc: <jbohac@novell.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Kerstin Jonsson <kerstin.jonsson@ericsson.com>
Cc: Avi Kivity <avi@redhat.com>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
Tested-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Thomas Renninger <trenn@suse.de>
LKML-Reference: <201005241913.o4OJDGWM010865@imap1.linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Jan Grossmann reported kernel boot panic while booting SMP
kernel on his system with a single core cpu. SMP kernels call
enable_IR_x2apic() from native_smp_prepare_cpus() and on
platforms where the kernel doesn't find SMP configuration we
ended up again calling enable_IR_x2apic() from the
APIC_init_uniprocessor() call in the smp_sanity_check(). Thus
leading to kernel panic.
Don't call enable_IR_x2apic() and default_setup_apic_routing()
from APIC_init_uniprocessor() in CONFIG_SMP case.
NOTE: this kind of non-idempotent and assymetric initialization
sequence is rather fragile and unclean, we'll clean that up
in v2.6.35. This is the minimal fix for v2.6.34.
Reported-by: Jan.Grossmann@kielnet.net
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: <jbarnes@virtuousgeek.org>
Cc: <david.woodhouse@intel.com>
Cc: <weidong.han@intel.com>
Cc: <youquan.song@intel.com>
Cc: <Jan.Grossmann@kielnet.net>
Cc: <stable@kernel.org> # [v2.6.32.x, v2.6.33.x]
LKML-Reference: <1270083887.7835.78.camel@sbs-t61.sc.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This patch replaces legacy PIC-related global variable and functions
with the new legacy_pic abstraction.
Signed-off-by: Jacob Pan <jacob.jun.pan@intel.com>
LKML-Reference: <43F901BD926A4E43B106BF17856F07559FB80D04@orsmsx508.amr.corp.intel.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
We need to fall back from logical-flat APIC mode to physical-flat mode
when we have more than 8 CPUs. However, in the presence of CPU
hotplug(with bios listing not enabled but possible cpus as disabled cpus in
MADT), we have to consider the number of possible CPUs rather than
the number of current CPUs; otherwise we may cross the 8-CPU boundary
when CPUs are added later.
32bit apic code can use more cleanups (like the removal of vendor checks in
32bit default_setup_apic_routing()) and more unifications with 64bit code.
Yinghai has some patches in works already. This patch addresses the boot issue
that is reported in the virtualization guest context.
[ hpa: incorporated function annotation feedback from Yinghai Lu ]
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
LKML-Reference: <1265767304.2833.19.camel@sbs-t61.sc.intel.com>
Acked-by: Shaohui Zheng <shaohui.zheng@intel.com>
Reviewed-by: Yinghai Lu <yinghai@kernel.org>
Cc: <stable@kernel.org>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Frans Pop <elendil@planet.nl>
Cc: Avi Kivity <avi@redhat.com>
Cc: x86@kernel.org
LKML-Reference: <1265478443-31072-10-git-send-email-elendil@planet.nl>
[ Left out the KVM bits. ]
Signed-off-by: Ingo Molnar <mingo@elte.hu>
We can use logical flat mode if there are <= 8 logical cpu's
(irrespective of physical apic id values). This will enable simplified
and efficient IPI and device interrupt routing on such platforms.
This has been tested to work on both Intel and AMD platforms.
Exceptions like IBM summit platform which can't use logical flat mode
are addressed by using OEM platform checks.
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Chris McDermott <lcm@linux.vnet.ibm.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Revert commit 2fbd07a5f5, as this commit
breaks an IBM platform with quad-core Xeon cpu's.
According to Suresh, this might be an IBM platform issue, as on other
Intel platforms with <= 8 logical cpu's, logical flat mode works fine
irespective of physical apic id values (inline with the xapic
architecture).
Revert this for now because of the IBM platform breakage.
Another version will be re-submitted after the complete analysis.
Signed-off-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Acked-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Print only once that the system is supporting x2apic mode.
Signed-off-by: Mike Travis <travis@sgi.com>
Acked-by: Cyrill Gorcunov <gorcunov@openvz.org>
LKML-Reference: <4B226E92.5080904@sgi.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
