Impact: fix redundant and incorrect check
Oleg Nesterov noticed wrt commit:
14fc9fb: x86: signal: check signal stack overflow properly
>> No need to check SA_ONSTACK if we're already using alternate signal stack.
>
> Yes, but this also mean that we don't need sas_ss_flags() under
> "if (!onsigstack)",
Checking on_sig_stack() in sas_ss_flags() at get_sigframe() is redundant
and not correct on 64 bit. To check sas_ss_size is enough.
Reported-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com>
Cc: roland@redhat.com
LKML-Reference: <49CBB54C.5080201@ct.jp.nec.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
* 'proc-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/adobriyan/proc:
Revert "proc: revert /proc/uptime to ->read_proc hook"
proc 2/2: remove struct proc_dir_entry::owner
proc 1/2: do PDE usecounting even for ->read_proc, ->write_proc
proc: fix sparse warnings in pagemap_read()
proc: move fs/proc/inode-alloc.txt comment into a source file
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/suspend-2.6:
PCI PM: Make pci_prepare_to_sleep() disable wake-up if needed
radeonfb: Use __pci_complete_power_transition()
PCI PM: Introduce __pci_[start|complete]_power_transition() (rev. 2)
PCI PM: Restore config spaces of all devices during early resume
PCI PM: Make pci_set_power_state() handle devices with no PM support
PCI PM: Put devices into low power states during late suspend (rev. 2)
PCI PM: Move pci_restore_standard_config to pci-driver.c
PCI PM: Use pci_set_power_state during early resume
PCI PM: Consistently use variable name "error" for pm call return values
kexec: Change kexec jump code ordering
PM: Change hibernation code ordering
PM: Change suspend code ordering
PM: Rework handling of interrupts during suspend-resume
PM: Introduce functions for suspending and resuming device interrupts
Setting ->owner as done currently (pde->owner = THIS_MODULE) is racy
as correctly noted at bug #12454. Someone can lookup entry with NULL
->owner, thus not pinning enything, and release it later resulting
in module refcount underflow.
We can keep ->owner and supply it at registration time like ->proc_fops
and ->data.
But this leaves ->owner as easy-manipulative field (just one C assignment)
and somebody will forget to unpin previous/pin current module when
switching ->owner. ->proc_fops is declared as "const" which should give
some thoughts.
->read_proc/->write_proc were just fixed to not require ->owner for
protection.
rmmod'ed directories will be empty and return "." and ".." -- no harm.
And directories with tricky enough readdir and lookup shouldn't be modular.
We definitely don't want such modular code.
Removing ->owner will also make PDE smaller.
So, let's nuke it.
Kudos to Jeff Layton for reminding about this, let's say, oversight.
http://bugzilla.kernel.org/show_bug.cgi?id=12454
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
* 'iommu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (60 commits)
dma-debug: make memory range checks more consistent
dma-debug: warn of unmapping an invalid dma address
dma-debug: fix dma_debug_add_bus() definition for !CONFIG_DMA_API_DEBUG
dma-debug/x86: register pci bus for dma-debug leak detection
dma-debug: add a check dma memory leaks
dma-debug: add checks for kernel text and rodata
dma-debug: print stacktrace of mapping path on unmap error
dma-debug: Documentation update
dma-debug: x86 architecture bindings
dma-debug: add function to dump dma mappings
dma-debug: add checks for sync_single_sg_*
dma-debug: add checks for sync_single_range_*
dma-debug: add checks for sync_single_*
dma-debug: add checking for [alloc|free]_coherent
dma-debug: add add checking for map/unmap_sg
dma-debug: add checking for map/unmap_page/single
dma-debug: add core checking functions
dma-debug: add debugfs interface
dma-debug: add kernel command line parameters
dma-debug: add initialization code
...
Fix trivial conflicts due to whitespace changes in arch/x86/kernel/pci-nommu.c
Use the functions introduced in by the previous patch,
suspend_device_irqs(), resume_device_irqs() and check_wakeup_irqs(),
to rework the handling of interrupts during suspend (hibernation) and
resume. Namely, interrupts will only be disabled on the CPU right
before suspending sysdevs, while device drivers will be prevented
from receiving interrupts, with the help of the new helper function,
before their "late" suspend callbacks run (and analogously during
resume).
In addition, since the device interrups are now disabled before the
CPU has turned all interrupts off and the CPU will ACK the interrupts
setting the IRQ_PENDING bit for them, check in sysdev_suspend() if
any wake-up interrupts are pending and abort suspend if that's the
case.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Ingo Molnar <mingo@elte.hu>
* 'x86-stage-3-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (190 commits)
Revert "cpuacct: reduce one NULL check in fast-path"
Revert "x86: don't compile vsmp_64 for 32bit"
x86: Correct behaviour of irq affinity
x86: early_ioremap_init(), use __fix_to_virt(), because we are sure it's safe
x86: use default_cpu_mask_to_apicid for 64bit
x86: fix set_extra_move_desc calling
x86, PAT, PCI: Change vma prot in pci_mmap to reflect inherited prot
x86/dmi: fix dmi_alloc() section mismatches
x86: e820 fix various signedness issues in setup.c and e820.c
x86: apic/io_apic.c define msi_ir_chip and ir_ioapic_chip all the time
x86: irq.c keep CONFIG_X86_LOCAL_APIC interrupts together
x86: irq.c use same path for show_interrupts
x86: cpu/cpu.h cleanup
x86: Fix a couple of sparse warnings in arch/x86/kernel/apic/io_apic.c
Revert "x86: create a non-zero sized bm_pte only when needed"
x86: pci-nommu.c cleanup
x86: io_delay.c cleanup
x86: rtc.c cleanup
x86: i8253 cleanup
x86: kdebugfs.c cleanup
...
Impact: cleanup
It's unused, since about 1995. So remove all initialization of it in
preparation for actually removing the field.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Some BIOSes report very high frequency transition latency which are plainly
wrong on CPus that can change frequency using native MSR interface.
One such system is IBM T42 (2327-8ZU) as reported by Owen Taylor and
Rik van Riel.
cpufreq_ondemand driver uses this transition latency to come up with a
reasonable sampling interval to sample CPU usage and with such high
latency value, ondemand sampling interval ends up being very high
(0.5 sec, in this particular case), resulting in performance impact due to
slow response to increasing frequency.
Fix it by capping-off the transition latency to 20uS for native MSR based
frequency transitions.
mjg: We've confirmed that this also helps on the X31
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Acked-by: Matthew Garrett <mjg@redhat.com>
Signed-off-by: Len Brown <len.brown@intel.com>
> arch/x86/kernel/cpu/cpufreq/longhaul.c: In function 'longhaul_setstate':
> arch/x86/kernel/cpu/cpufreq/longhaul.c:308: error: implicit declaration of function 'acpi_set_register'
Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Compile-tested-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Len Brown <len.brown@intel.com>
* 'sched-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (46 commits)
sched: Add comments to find_busiest_group() function
sched: Refactor the power savings balance code
sched: Optimize the !power_savings_balance during fbg()
sched: Create a helper function to calculate imbalance
sched: Create helper to calculate small_imbalance in fbg()
sched: Create a helper function to calculate sched_domain stats for fbg()
sched: Define structure to store the sched_domain statistics for fbg()
sched: Create a helper function to calculate sched_group stats for fbg()
sched: Define structure to store the sched_group statistics for fbg()
sched: Fix indentations in find_busiest_group() using gotos
sched: Simple helper functions for find_busiest_group()
sched: remove unused fields from struct rq
sched: jiffies not printed per CPU
sched: small optimisation of can_migrate_task()
sched: fix typos in documentation
sched: add avg_overlap decay
x86, sched_clock(): mark variables read-mostly
sched: optimize ttwu vs group scheduling
sched: TIF_NEED_RESCHED -> need_reshed() cleanup
sched: don't rebalance if attached on NULL domain
...
* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/davej/cpufreq: (35 commits)
[CPUFREQ] Prevent p4-clockmod from auto-binding to the ondemand governor.
[CPUFREQ] Make cpufreq-nforce2 less obnoxious
[CPUFREQ] p4-clockmod reports wrong frequency.
[CPUFREQ] powernow-k8: Use a common exit path.
[CPUFREQ] Change link order of x86 cpufreq modules
[CPUFREQ] conservative: remove 10x from def_sampling_rate
[CPUFREQ] conservative: fixup governor to function more like ondemand logic
[CPUFREQ] conservative: fix dbs_cpufreq_notifier so freq is not locked
[CPUFREQ] conservative: amend author's email address
[CPUFREQ] Use swap() in longhaul.c
[CPUFREQ] checkpatch cleanups for acpi-cpufreq
[CPUFREQ] powernow-k8: Only print error message once, not per core.
[CPUFREQ] ondemand/conservative: sanitize sampling_rate restrictions
[CPUFREQ] ondemand/conservative: deprecate sampling_rate{min,max}
[CPUFREQ] powernow-k8: Always compile powernow-k8 driver with ACPI support
[CPUFREQ] Introduce /sys/devices/system/cpu/cpu*/cpufreq/cpuinfo_transition_latency
[CPUFREQ] checkpatch cleanups for powernow-k8
[CPUFREQ] checkpatch cleanups for ondemand governor.
[CPUFREQ] checkpatch cleanups for powernow-k7
[CPUFREQ] checkpatch cleanups for speedstep related drivers.
...
Partial revert of commit 129d8bc828
titled 'x86: don't compile vsmp_64 for 32bit'
Commit reverted to compile vsmp_64.c if CONFIG_X86_64 is defined,
since is_vsmp_box() needs to indicate that TSCs are not synchronized, and
hence, not a valid time source, even when CONFIG_X86_VSMP is not defined.
Signed-off-by: Ravikiran Thirumalai <kiran@scalex86.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: shai@scalex86.org
LKML-Reference: <20090324061429.GH7278@localdomain>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Fix interrupt emulation code in kretprobe-booster according to
pt_regs update (es/ds change and gs adding).
This issue has been reported on systemtap-bugzilla:
http://sources.redhat.com/bugzilla/show_bug.cgi?id=9965
| On a -tip kernel on x86_32, kretprobe_example (from samples) triggers the
| following backtrace when its retprobing a class of functions that cause a
| copy_from/to_user().
|
| BUG: sleeping function called from invalid context at mm/memory.c:3196
| in_atomic(): 0, irqs_disabled(): 1, pid: 2286, name: cat
Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Tested-by: Bharata B Rao <bharata@linux.vnet.ibm.com>
Cc: systemtap-ml <systemtap@sources.redhat.com>
LKML-Reference: <49C7995C.2010601@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: get correct smp_affinity as user requested
The effect of setting desc->affinity (ie. from userspace via sysfs) has
varied over time. In 2.6.27, the 32-bit code anded the value with
cpu_online_map, and both 32 and 64-bit did that anding whenever a cpu
was unplugged.
2.6.29 consolidated this into one routine (and fixed hotplug) but
introduced another variation: anding the affinity with cfg->domain.
We should just set it to what the user said - if possible.
(cpu_mask_to_apicid_and already takes cpu_online_mask into account)
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Acked-by: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
LKML-Reference: <49C94DDF.2010703@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: fix bug with irq-descriptor moving when logical flat
Rusty observed:
> The effect of setting desc->affinity (ie. from userspace via sysfs) has varied
> over time. In 2.6.27, the 32-bit code anded the value with cpu_online_map,
> and both 32 and 64-bit did that anding whenever a cpu was unplugged.
>
> 2.6.29 consolidated this into one routine (and fixed hotplug) but introduced
> another variation: anding the affinity with cfg->domain. Is this right, or
> should we just set it to what the user said? Or as now, indicate that we're
> restricting it.
Eric pointed out that desc->affinity should be what the user requested,
if it is at all possible to honor the user space request.
This bug got introduced by commit 22f65d31b "x86: Update io_apic.c to use
new cpumask API".
Fix it by moving the masking to before the descriptor moving ...
Reported-by: Rusty Russell <rusty@rustcorp.com.au>
Reported-by: Eric W. Biederman <ebiederm@xmission.com>
LKML-Reference: <49C94134.4000408@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This patch move the timestamp from happening in the arch specific
code into the general code. This allows for better control by the tracer
to time manipulation.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
This iommu_op can tell if domain have a specific capability, like snooping
control for Intel IOMMU, which can be used by other components of kernel to
adjust the behaviour.
Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Impact: cleanup
This fixed various signedness issues in setup.c and e820.c:
arch/x86/kernel/setup.c:455:53: warning: incorrect type in argument 3 (different signedness)
arch/x86/kernel/setup.c:455:53: expected int *pnr_map
arch/x86/kernel/setup.c:455:53: got unsigned int extern [toplevel] *<noident>
arch/x86/kernel/setup.c:639:53: warning: incorrect type in argument 3 (different signedness)
arch/x86/kernel/setup.c:639:53: expected int *pnr_map
arch/x86/kernel/setup.c:639:53: got unsigned int extern [toplevel] *<noident>
arch/x86/kernel/setup.c:820:54: warning: incorrect type in argument 3 (different signedness)
arch/x86/kernel/setup.c:820:54: expected int *pnr_map
arch/x86/kernel/setup.c:820:54: got unsigned int extern [toplevel] *<noident>
arch/x86/kernel/e820.c:670:53: warning: incorrect type in argument 3 (different signedness)
arch/x86/kernel/e820.c:670:53: expected int *pnr_map
arch/x86/kernel/e820.c:670:53: got unsigned int [toplevel] *<noident>
Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com>
move out msi_ir_chip and ir_ioapic_chip from CONFIG_INTR_REMAP shadow
Fix:
arch/x86/kernel/apic/io_apic.c:1431: warning: ‘msi_ir_chip’ defined but not used
Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com>
Impact: cleanup
This patch fixes the following sparse warnings:
arch/x86/kernel/apic/io_apic.c:3602:17: warning: symbol 'hpet_msi_type'
was not declared. Should it be static?
arch/x86/kernel/apic/io_apic.c:3467:30: warning: Using plain integer as
NULL pointer
Signed-off-by: Dmitri Vorobiev <dmitri.vorobiev@movial.com>
LKML-Reference: <1237741871-5827-2-git-send-email-dmitri.vorobiev@movial.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
To reduce the size of the oversized function __get_smp_config()
There should be no impact to functionality.
Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com>
Impact: fix incorrect error message
- IO APIC resource allocation error message contains one too many "be".
- Print the error message iff there are IO APICs in the system.
I've seen this error message for some time on my x86-32 laptop...
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Cc: Alan Bartlett <ajb.stxsl@googlemail.com>
LKML-Reference: <200903202100.30789.bzolnier@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: cleanup
Check alternate signal stack overflow with proper stack pointer.
The stack pointer of the next signal frame is different if that
task has i387 state.
On x86_64, redzone would be included.
No need to check SA_ONSTACK if we're already using alternate signal stack.
Signed-off-by: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com>
Cc: Roland McGrath <roland@redhat.com>
LKML-Reference: <49C2874D.3080002@ct.jp.nec.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Add the new API pci_enable_msi_block() to allow drivers to
request multiple MSI and reimplement pci_enable_msi in terms of
pci_enable_msi_block. Ensure that the architecture back ends don't
have to know about multiple MSI.
Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
This patch changes a VIA PCI quirk to use dev_info() rather than printk().
Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgek.org>
When I review the sensitive code ftrace_nmi_enter(), I found
the atomic variable nmi_running does protect NMI VS do_ftrace_mod_code(),
but it can not protects NMI(entered nmi) VS NMI(ftrace_nmi_enter()).
cpu#1 | cpu#2 | cpu#3
ftrace_nmi_enter() | do_ftrace_mod_code() |
not modify | |
------------------------|-----------------------|--
executing | set mod_code_write = 1|
executing --|-----------------------|--------------------
executing | | ftrace_nmi_enter()
executing | | do modify
------------------------|-----------------------|-----------------
ftrace_nmi_exit() | |
cpu#3 may be being modified the code which is still being executed on cpu#1,
it will have undefined results and possibly take a GPF, this patch
prevents it occurred.
Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
LKML-Reference: <49C0B411.30003@cn.fujitsu.com>
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Impact: cleanup
Refactor the MP-table parsing code via the introduction of the
following helper functions:
skip_entry()
smp_reserve_bootmem()
check_irq_src()
check_slot()
To simplify the code flow and to reduce the size of the
following oversized functions: smp_read_mpc(), smp_scan_config().
There should be no impact to functionality.
Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: cleanup, avoid cpumask games
The APM code wants to run on CPU 0: we create an "on_cpu0" wrapper
which uses work_on_cpu() if we're not already on cpu 0.
This introduces a new failure mode: -ENOMEM, so we add an explicit
err arg and handle Linux-style errnos in apm_err().
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
LKML-Reference: <200903111631.29787.rusty@rustcorp.com.au>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: don't play with current's cpumask
Straightforward indirection through work_on_cpu(). One change is
that the error code from microcode_update_cpu() is now actually
plumbed back to microcode_init_cpu(), so now we printk if it fails
on cpu hotplug.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Dmitry Adamushko <dmitry.adamushko@gmail.com>
Cc: Peter Oruba <peter.oruba@amd.com>
LKML-Reference: <200903111632.37279.rusty@rustcorp.com.au>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
arch/x86/kernel/cpu/mtrr/cleanup.c:197: warning: format ‘%d’ expects type ‘int’, but argument 2 has type ‘long unsigned int’
Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com>
Cc: Yinghai Lu <yinghai@kernel.org>
LKML-Reference: <1237378015.13488.1.camel@localhost.localdomain>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: fix boot crash on UV systems
Commit 76ba0ecda0 "cpumask: use
cpumask_var_t in uv_flush_tlb_others" used cur_cpu as an iterator;
it was supposed to be zero for the code below it.
Reported-by: Cliff Wickman <cpw@sgi.com>
Original-From: Cliff Wickman <cpw@sgi.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Acked-by: Mike Travis <travis@sgi.com>
Cc: steiner@sgi.com
Cc: <stable@kernel.org>
LKML-Reference: <200903180822.31196.rusty@rustcorp.com.au>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: Fix cpu offline when CONFIG_MAXSMP=y
Changeset bc9b83dd1f "cpumask: convert
c1e_mask in arch/x86/kernel/process.c to cpumask_var_t" contained a
bug: c1e_mask is manipulated even if C1E isn't detected (and hence
not allocated).
This is simply fixed by checking for NULL (which gcc optimizes out
anyway of CONFIG_CPUMASK_OFFSTACK=n, since it knows ce1_mask can never
be NULL).
In addition, fix a leak where select_idle_routine re-allocates
(and re-clears) c1e_mask on every cpu init.
Reported-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: Mike Travis <travis@sgi.com>
LKML-Reference: <200903171450.34549.rusty@rustcorp.com.au>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: optimize APIC IPI related barriers
Uncached MMIO accesses for xapic are inherently serializing and hence
we don't need explicit barriers for xapic IPI paths.
x2apic MSR writes/reads don't have serializing semantics and hence need
a serializing instruction or mfence, to make all the previous memory
stores globally visisble before the x2apic msr write for IPI.
Add x2apic_wrmsr_fence() in flush tlb path to x2apic specific paths.
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Jens Axboe <jens.axboe@oracle.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: "steiner@sgi.com" <steiner@sgi.com>
Cc: Nick Piggin <npiggin@suse.de>
LKML-Reference: <1237313814.27006.203.camel@localhost.localdomain>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Attempting to rid us of the problematic work_on_cpu(). Just use
smp_call_function_single() here.
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
LKML-Reference: <20090318042217.EF3F1DDF39@ozlabs.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: fix spurious IRQs
During irq migration, we send a low priority interrupt to the previous
irq destination. This happens in non interrupt-remapping case after interrupt
starts arriving at new destination and in interrupt-remapping case after
modifying and flushing the interrupt-remapping table entry caches.
This low priority irq cleanup handler can cleanup multiple vectors, as
multiple irq's can be migrated at almost the same time. While
there will be multiple invocations of irq cleanup handler (one cleanup
IPI for each irq migration), first invocation of the cleanup handler
can potentially cleanup more than one vector (as the first invocation can
see the requests for more than vector cleanup). When we cleanup multiple
vectors during the first invocation of the smp_irq_move_cleanup_interrupt(),
other vectors that are to be cleanedup can still be pending in the local
cpu's IRR (as smp_irq_move_cleanup_interrupt() runs with interrupts disabled).
When we are ready to unhook a vector corresponding to an irq, check if that
vector is registered in the local cpu's IRR. If so skip that cleanup and
do a self IPI with the cleanup vector, so that we give a chance to
service the pending vector interrupt and then cleanup that vector
allocation once we execute the lowest priority handler.
This fixes spurious interrupts seen when migrating multiple vectors
at the same time.
[ This is apparently possible even on conventional xapic, although to
the best of our knowledge it has never been seen. The stable
maintainers may wish to consider this one for -stable. ]
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Cc: stable@kernel.org
Impact: fix possible race
save_mask_IO_APIC_setup() was using non atomic memory allocation while getting
called with interrupts disabled. Fix this by splitting this into two different
function. Allocation part save_IO_APIC_setup() now happens before
disabling interrupts.
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Impact: cleanup
Clean up #ifdefs and replace them with helper functions.
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Impact: simplification
In the current code, for level triggered migration, we need to modify the
io-apic RTE with the update vector information, along with modifying interrupt
remapping table entry(IRTE) with vector and destination. This is to ensure that
remote IRR bit inthe IOAPIC RTE gets cleared when the cpu does EOI.
With this patch, for level triggered, we eliminate the io-apic RTE modification
(with the updated vector information), by using a virtual vector (io-apic pin
number). Real vector that is used for interrupting cpu will be coming from
the interrupt-remapping table entry. Trigger mode in the IRTE will always be
edge, and the actual level or edge trigger will be setup in the IO-APIC RTE.
So a level triggered interrupt will appear as an edge to the local apic
cpu but still as level to the IO-APIC.
With this change, level irq migration can be done by simply modifying
the interrupt-remapping table entry with out changing the io-apic RTE.
And as the interrupt appears as edge at the cpu, in addition to do the
local apic EOI, we need to do IO-APIC directed EOI to clear the remote
IRR bit in the IO-APIC RTE.
This simplies the irq migration in the presence of interrupt-remapping.
Idea-by: Rajesh Sankaran <rajesh.sankaran@intel.com>
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Impact: cleanup, paranoia
We were not clearing the local APIC in clear_local_APIC() in the
presence of x2apic. Fix it.
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Impact: make kexec work with x2apic
disable_IO_APIC() gets called during crashdump aswell, which configures the
IO-APIC/LAPIC so that legacy interrupts can be delivered for the kexec'd kernel.
In the presence of interrupt-remapping, we need to change the
interrupt-remapping configuration aswell as modifying IO-APIC for virtual wire
B mode.
To keep things simple during the crash, use virtual wire A mode
(for which we don't need to touch io-apic and interrupt-remapping tables).
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Impact: interface augmentation (not yet used)
Enable fault handling flow for intr-remapping aswell. Fault handling
code now shared by both dma-remapping and intr-remapping.
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Impact: build fix with CONFIG_RELOCATABLE
Move _end into a dummy section, so that relocs.c will know it is a
relocatable symbol.
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Cc: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Impact: disambiguate real .bss variables from .brk storage
Add a .brk section after the .bss section. This has no effect
on the final vmlinux, but it more clearly distinguishes the space
taken by actual .bss symbols, and the variable space reserved
by .brk users.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Impact: Tighten bound to avoid masking errors
The definition of MAPPING_BEYOND_END was excessive; this has a nasty
tendency to mask bugs. We have learned over time that this kind of
bug hiding can cause some very strange errors. Therefore, tighten the
bound to only need to map the actual kernel area.
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Cc: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Impact: cleanup
ALLOCATOR_SLOP is a vestigial remain from when we used the
bootmem allocator to allocate the kernel's linear memory mapping.
Now we directly reserve pages from the e820 mapping, and no
longer require secondary structures to keep track of allocated
pages.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Impact: crash fix
head_32.S needs to map the kernel itself, and enough space so
that mm/init.c can allocate space from the e820 allocator
for the linear map of low memory.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Don't boost at the addresses which are listed on exception tables,
because major page fault will occur on those addresses. In that case,
kprobes can not ensure that when instruction buffer can be freed since
some processes will sleep on the buffer.
kprobes-ia64 already has same check.
Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In order for ntpd to correctly synchronize the clocks, the frequency of
the system clock must not be off by more than 500 ppm (or, put another
way, 1:2000), or ntpd will end up giving up on trying to synchronize
properly, and ends up reseting the clock in jumps instead.
The fast TSC PIT calibration sometimes failed this test - it was
assuming that the PIT reads always took about one microsecond each (2us
for the two reads to get a 16-bit timer), and that calibrating TSC to
the PIT over 15ms should thus be sufficient to get much closer than
500ppm (max 2us error on both sides giving 4us over 15ms: a 270 ppm
error value).
However, that assumption does not always hold: apparently some hardware
is either very much slower at reading the PIT registers, or there was
other noise causing at least one machine to get 700+ ppm errors.
So instead of using a fixed 15ms timing loop, this changes the fast PIT
calibration to read the TSC delta over the individual PIT timer reads,
and use the result to calculate the error bars on the PIT read timing
properly. We then successfully calibrate the TSC only if the maximum
error bars fall below 500ppm.
In the process, we also relax the timing to allow up to 25ms for the
calibration, although it can happen much faster depending on hardware.
Reported-and-tested-by: Jesper Krogh <jesper@krogh.cc>
Cc: john stultz <johnstul@us.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
During bootup, when we reprogram the PIT (programmable interval timer)
to start counting down from 0xffff in order to use it for the fast TSC
calibration, we should also make sure to delay a bit afterwards to allow
the PIT hardware to actually start counting with the new value.
That will happens at the next CLK pulse (1.193182 MHz), so the easiest
way to do that is to just wait at least one microsecond after
programming the new PIT counter value. We do that by just reading the
counter value back once - which will take about 2us on PC hardware.
Reported-and-tested-by: john stultz <johnstul@us.ibm.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Impact: don't trim e820 according to wrong mtrr
Ozan reports that his server emits strange warning.
it turns out the BIOS sets the MTRRs incorrectly.
Ignore those strange ranges, and don't trim e820,
just emit one warning about BIOS
Reported-by: Ozan Çağlayan <ozan@pardus.org.tr>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
LKML-Reference: <49BEE1E7.7020706@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: Bug fix on UP
Referring commit cc3ca22063,
Peter removed __cpuinit annotations for mce_cpu_features()
and its successor functions, which caused troubles on UP
configurations.
However the intel_init_cmci() was introduced after that and
it also has __cpuinit annotation even though it is called from
mce_cpu_features(). Remove the annotation from that function
too.
Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: help debug e820 bugs
Try to print out more info, to catch wrong call parameters.
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
LKML-Reference: <49BCB557.3030000@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: fix boot crash
Need to exit early if the addr is far above 64k.
The crash got exposed by:
78a8b35: x86: make e820_update_range() handle small range update
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Cc: <stable@kernel.org>
LKML-Reference: <49BC2279.2030101@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: makes vmlinux section information more useful
Don't use ram after _end blindly for pagetables. aka init pages is before _end
put those pg table into .bss
[Adapted to use brk segment - Jeremy]
v2: keep initial page table up to 512M only.
v4: put initial page tables just before _end
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Impact: new interface; remove hard-coded limit
Add RESERVE_BRK(name, size) macro to reserve space in the brk
area. This should be a conservative (ie, larger) estimate of
how much space might possibly be required from the brk area.
Any unused space will be freed, so there's no real downside
on making the reservation too large (within limits).
The name should be unique within a given file, and somewhat
descriptive.
The C definition of RESERVE_BRK() ends up being more complex than
one would expect to work around a cluster of gcc infelicities:
The first attempt was to simply try putting __section(.brk_reservation)
on a variable. This doesn't work because it ends up making it a
@progbits section, which gets actual space allocated in the vmlinux
executable.
The second attempt was to emit the space into a section using asm,
but gcc doesn't allow arguments to be passed to file-level asm()
statements, making it hard to pass in the size.
The final attempt is to wrap the asm() in a function to allow
it to have arguments, and put the function itself into the
.discard section, which vmlinux*.lds drops entirely from the
emitted vmlinux.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Impact: simplification
We only need to map the kernel in head_32.S, not the whole of
lowmem. We use 512MB as a reasonable (but arbitrary) limit on
the maximum size of the kernel image.
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Impact: use new interface instead of previous ad hoc implementation
Use extend_brk() to allocate memory for DMI rather than having an
ad-hoc allocator.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Impact: use new interface instead of previous ad hoc implementation
Rather than having special purpose init_pg_table_start/end variables
to delimit the kernel pagetable built by head_32.S, just use the brk
mechanism to extend the bss for the new pagetable.
This patch removes init_pg_table_start/end and pg0, defines __brk_base
(which is page-aligned and immediately follows _end), initializes
the brk region to start there, and uses it for the 32-bit pagetable.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Impact: build fix
The brk initialization functions were incorrectly located inside
an #ifdef CONFIG_VLK_DEV_INITRD block, causing the obvious build failure in
minimal configurations.
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Cc: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Hiroshi Shimamoto