It was only needed for APM
Pointed out by Jan Beulich
Cc: jbeulich@novell.com
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
X86_FEATURE_K8_C was a synthetic Linux CPUID flag that was used for some
code optimizations in Opteron C stepping or later. But support for pre C
stepping optimizations has been removed, so this isn't needed anymore.
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
They used to be used by the reboot code, but not anymore.
Noticed by Jan Beulich
Cc: JBeulich@novell.com
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
o Currently, during kexec reboot, IOAPIC is re-programmed back to virtual
wire mode if there was an i8259 connected to it. This enables getting
timer interrupts in second kernel in legacy mode.
o After putting into virtual wire mode, IOAPIC delivers the i8259 interrupts
to CPU0. This works well for kexec but not for kdump as we might crash
on a different CPU and second kernel will not see timer interrupts.
o This patch modifies the redirection table entry to deliver the timer
interrupts to the cpu we are rebooting (instead of hardcoding to zero).
This ensures that second kernel receives timer interrupts even on a
non-boot cpu.
Signed-off-by: Vivek Goyal <vgoyal@in.ibm.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Introduce vSMP arch to the kernel.
This patch:
1. Adds CONFIG_X86_VSMP
2. Adds machine specific macros for local_irq_disabled, local_irq_enabled
and irqs_disabled
3. Writes to the vSMP CTL device to indicate kernel compiled with CONFIG_VSMP
Signed-off-by: Ravikiran Thirumalai <kiran@scalemp.com>
Signed-off-by: Shai Fultheim <shai@scalemp.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Currently we attempt to restore virtual wire mode on reboot, which only
works if we can figure out where the i8259 is connected. This is very
useful when we are kexec another kernel and likely helpful to an peculiar
BIOS that make assumptions about how the system is setup.
Since the acpi MADT table does not provide the location where the i8259 is
connected we have to look at the hardware to figure it out.
Most systems have the i8259 connected the local apic of the cpu so won't be
affected but people running Opteron and some serverworks chipsets should be
able to use kexec now.
In addition this patch removes the hard coded assumption that the io_apic
that delivers isa interrups is always known to the kernel as io_apic 0.
There does not appear to be anything to guarantee that assumption is true.
And From: Vivek Goyal <vgoyal@in.ibm.com>
A minor fix to the patch which remembers the location of where i8259 is
connected. Now counter i has been replaced by apic. counter i is having
some junk value which was leading to non-detection of i8259 connected to
IOAPIC.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Vivek Goyal <vgoyal@in.ibm.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Setting RF (resume flag) allows a debugger to resume execution after a code
breakpoint without tripping the breakpoint again. It is reset by the CPU
after executing one instruction.
Signed-off-by: Chuck Ebbert <76306.1226@compuserve.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
It was set as an NMI, but the NMI bit always forces an interrupt
to end up at vector 2. So it was never used. Remove.
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Fix
CC arch/x86_64/kernel/nmi.o
linux/arch/x86_64/kernel/nmi.c: In function ???check_nmi_watchdog???:
linux/arch/x86_64/kernel/nmi.c:155: warning: statement with no effect
on Uniprocessor builds.
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Patch uses a static PDA array early at boot and reallocates processor PDA
with node local memory when kmalloc is ready, just before pda_init.
The boot_cpu_pda is needed since the cpu_pda is used even before pda_init for
that cpu is called (to set the static per-cpu areas offset table etc)
Signed-off-by: Ravikiran Thirumalai <kiran@scalex86.org>
Signed-off-by: Shai Fultheim <shai@scalex86.org>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Patch enables early intialization of cpu_to_node.
apicid_to_node is built by reading the SRAT table, from acpi_numa_init with
ACPI_NUMA and k8_scan_nodes with K8_NUMA.
x86_cpu_to_apicid is built by parsing the ACPI MADT table, from acpi_boot_init.
We combine these two tables and setup cpu_to_node.
Early intialization helps the static per_cpu_areas in getting pages from
correct node.
Change since last release:
Do not initialize early init_cpu_to_node for faking node cases.
Patch tested on TYAN dual core 4P board with K8 only, ACPI_NUMA.
Tested on EM64T NUMA. Also tested with numa=off, numa=fake, and running
a kernel compiled with NUMA on a regular EM64 2 way SMP.
Signed-off-by: Alok N Kataria <alokk@calsoftinc.com>
Signed-off-by: Ravikiran Thirumalai <kiran@scalex86.org>
Signed-off-by: Shai Fultheim <shai@scalex86.org>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The real vsyscall .text addresses are not mapped when the alternative()
replacement runs early, so use some black magic to access them using
the direct mapping.
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
They already do this in hardware and the Linux algorithm
actually adds errors.
Cc: mingo@elte.hu
Cc: rohit.seth@intel.com
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
o Apic id is in most significant 8 bits of APIC_ID register. Current code
is trying to write apic id to least significant 8 bits. This patch fixes
it.
o This fix enables booting uni kdump capture kernel on a cpu with non-zero
apic id.
Signed-off-by: Vivek Goyal <vgoyal@in.ibm.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Remove exports that are already exported from the object's source file.
Signed-off-by: Brian Gerst <bgerst@didntduck.org>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
These functions are inlines and shouldn't be exported.
Signed-off-by: Brian Gerst <bgerst@didntduck.org>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
AK: I hacked Muli's original patch a lot and there were a lot
of changes - all bugs are probably to blame on me now.
There were also some changes in the fall back behaviour
for swiotlb - in particular it doesn't try to use GFP_DMA
now anymore. Also all DMA mapping operations use the
same core dma_alloc_coherent code with proper fallbacks now.
And various other changes and cleanups.
Known problems: iommu=force swiotlb=force together breaks
needs more testing.
This patch cleans up x86_64's DMA mapping dispatching code. Right now
we have three possible IOMMU types: AGP GART, swiotlb and nommu, and
in the future we will also have Xen's x86_64 swiotlb and other HW
IOMMUs for x86_64. In order to support all of them cleanly, this
patch:
- introduces a struct dma_mapping_ops with function pointers for each
of the DMA mapping operations of gart (AMD HW IOMMU), swiotlb
(software IOMMU) and nommu (no IOMMU).
- gets rid of:
if (swiotlb)
return swiotlb_xxx();
- PCI_DMA_BUS_IS_PHYS is now checked against the dma_ops being set
This makes swiotlb faster by avoiding double copying in some cases.
Signed-Off-By: Muli Ben-Yehuda <mulix@mulix.org>
Signed-Off-By: Jon D. Mason <jdmason@us.ibm.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This adds a new notifier chain that is called with IDLE_START
when a CPU goes idle and IDLE_END when it goes out of idle.
The context can be idle thread or interrupt context.
Since we cannot rely on MONITOR/MWAIT existing the idle
end check currently has to be done in all interrupt
handlers.
They were originally inspired by the similar s390 implementation.
They have a variety of applications:
- They will be needed for CONFIG_NO_IDLE_HZ
- They can be used for oprofile to fix up the missing time
in idle when performance counters don't tick.
- They can be used for better C state management in ACPI
- They could be used for microstate accounting.
This is just infrastructure so far, no users.
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Fix off by one when checking if the machine has enougn memory to need IOMMU
This caused the IOMMUs to be needlessly enabled for mem=4G
Based on a patch from Jon Mason
Signed-off-by: jdmason@us.ibm.com
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Whenever we see that a CPU is capable of C3 (during ACPI cstate init), we
disable local APIC timer and switch to using a broadcast from external timer
interrupt (IRQ 0).
Patch below adds the code for x86_64.
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Remove the finer control of local APIC timer. We cannot provide a sub-jiffy
control like this when we use broadcast from external timer in place of
local APIC. Instead of removing this only on systems that may end up using
broadcast from external timer (due to C3), I am going the
"I'm feeling lucky" way to remove this fully. Basically, I am not sure about
usefulness of this code today. Few other architectures also don't seem to
support this today.
If you are using profiling and fine grained control and don't like this going
away in normal case, yell at me right now.
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
I would like to throw out a suggestion for a possible change in the way that
the debug register traps are handled in do_debug() when the trap occurs
in kernel-mode.
In the x86_64 version of do_debug(), the code will skip around sending
a SIGTRAP to the current task if the trap occurred while in kernel mode.
On the i386-side of things, if the access happens to occur in kernel mode
(say during a read(2) of user's buffer that matches the address of a
debug register trap), then the do_debug() routine for i386 will go ahead
and call send_sigtrap() and send the SIGTRAP signal. The send_sigtrap()
code will also set the info.si_addr to NULL in this case (even though I
don't understand why, since the SIGTRAP siginfo processing doesn't use
the si_addr field...).
So I would like to suggest that the x86_64 do_debug() routine also
follow this type of behavior and have it go ahead and send the
SIGTRAP signal to the current task, even if the debug register trap
happens to have occurred in kernel mode. I have taken a stab at
a patch for this change below. (It includes the i386-ish change
for setting si_addr to NULL when the trap occurred in kernel mode.)
It seems like a useful feature to be able to 'watch' a user location that
might also be modified in the kernel via a system service call, and have the
debugger report that information back to the user, rather than to just
silently ignore the trap.
Additionally, I realize that users that pull in a kernel debugger such as
KGDB into their kernel might want to remove this change below when they add
in KGDB support. However, they could alternatively look at the current
task's thread.debugreg[] values to see if the trap occurred due to KGDB
or instead because of a user-space debugger trap, and still honor the
user SIGTRAP processing (instead of the KGDB breakpoint processing)
if the trap matches up with the thread.debugreg[] registers.
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch is on the same lines as Zachary Amsden's i386 GDT page alignemnt
patch in -mm, but for x86_64.
Patch to align and pad x86_64 GDT on page boundries.
[AK: some minor cleanups and fixed incorrect TLS initialization
in CPU init.]
Signed-off-by: Nippun Goel <nippung@calsoftinc.com>
Signed-off-by: Ravikiran Thirumalai <kiran@scalex86.org>
Signed-off-by: Shai Fultheim <shai@scalex86.org>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This might help on distributions that use a 32bit biarch compiler.
First pass -m64 by default.
Secondly add some more .code32s because at least the Ubuntu biarch
32bit as called by gcc doesn't seem to handle -m64 -m32 as generated
by the Makefile without such assistance.
And finally make sure the linker script can be preprocessed
with a 32bit cpp.
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Some people need it now on 64bit so reuse the i386 code for
x86-64. This will be also useful for future bug workarounds.
It is a bit simplified there because there is no need
to do it very early on x86-64. This means it doesn't need
early ioremap et.al. We run it as a core initcall right now.
I hope it's not needed for early setup.
I added a general CONFIG_DMI symbol in case IA64 or someone
else wants to reuse the code later too.
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The introduction of call_softirq switching to the interrupt stack several
releases earlier resulted in a problem with the code in show_trace, which
assumes that it can pick the previous stack pointer from the end of the
interrupt stack.
Cc: Andi Kleen <ak@muc.de>
Cc: Arjan van de Ven <arjanv@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
So why are we calling smp_send_stop from machine_halt?
We don't.
Looking more closely at the bug report the problem here
is that halt -p is called which triggers not a halt but
an attempt to power off.
machine_power_off calls machine_shutdown which calls smp_send_stop.
If pm_power_off is set we should never make it out machine_power_off
to the call of do_exit. So pm_power_off must not be set in this case.
When pm_power_off is not set we expect machine_power_off to devolve
into machine_halt.
So how do we fix this?
Playing too much with smp_send_stop is dangerous because it
must also be safe to be called from panic.
It looks like the obviously correct fix is to only call
machine_shutdown when pm_power_off is defined. Doing
that will make Andi's assumption about not scheduling
true and generally simplify what must be supported.
This turns machine_power_off into a noop like machine_halt
when pm_power_off is not defined.
If the expected behavior is that sys_reboot(LINUX_REBOOT_CMD_POWER_OFF)
becomes sys_reboot(LINUX_REBOOT_CMD_HALT) if pm_power_off is NULL
this is not quite a comprehensive fix as we pass a different parameter
to the reboot notifier and we set system_state to a different value
before calling device_shutdown().
Unfortunately any fix more comprehensive I can think of is not
obviously correct. The core problem is that there is no architecture
independent way to detect if machine_power will become a noop, without
calling it.
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
I noticed that some lowlevel send_IPI_mask helpers had a hotplug/preempt
race whereupon the cpu_online_map was read before disabling preemption;
...
cpumask_t mask = cpu_online_map;
int cpu = get_cpu();
cpu_clear(cpu, mask);
...
But then i realised that there is no need for these lowlevel functions to
be going through all this trouble when all the callers are already made
hotplug/preempt safe.
Signed-off-by: Zwane Mwaikambo <zwane@arm.linux.org.uk>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
There is one CPU here whose MCE bank count is 6. This patch increases
x86_64's MCE bank count.
Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The following is probably a good idea given that the atomic_set() isn't
a barrier here either.
Signed-off-by: Benjamin LaHaise <benjamin.c.lahaise@intel.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This
- switches the INT3 handler to run on an IST stack (to cope with
breakpoints set by a kernel debugger on places where the kernel's
%gs base hasn't been set up, yet); the IST stack used is shared with
the INT1 handler's
[AK: this also allows setting a kprobe on the interrupt/exception entry
points]
- allows nesting of INT1/INT3 handlers so that one can, with a kernel
debugger, debug (at least) the user-mode portions of the INT1/INT3
handling; the nesting isn't actively enabled here since a kernel-
debugger-free kernel doesn't need it
Signed-Off-By: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Print bits for RDTSCP, SVM, CR8-LEGACY.
Also now print power flags on i386 like x86-64 always did.
This will add a new line in the 386 cpuinfo, but that shouldn't
be an issue - did that in the past too and I haven't heard
of any breakage.
I shrunk some of the fields in the i386 cpuinfo_x86 to chars
to make up for the new int "x86_power" field. Overall it's
smaller than before.
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Define it for i386 too.
This is a synthetic flag that signifies that the CPU's TSC runs
at a constant P state invariant frequency.
Fix up the logic on x86-64/i386 to set it on all known CPUs.
Use the AMD defined bit to set it on future AMD CPUs.
Cc: venkatesh.pallipadi@intel.com
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Was only used by the floppy driver to work around some ancient
hardware bug that should never occur on any 64bit system.
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Most users don't need it so no need to waste memory.
This means an user has to specify the appropiate number of
hotplug CPUs on the command line with additional_cpus=...
or fix their BIOS to follow the convention in
Documentation/x86-64/cpu-hotplug-spec
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Make sure no iret can fault without attached recovery code.
Cannot happen in the normal case, but might be useful
with kernel debuggers
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Since a double fault always implies that kernel data structures are
corrupt, this fault should neither be handed to user mode handling,
nor should the handler allow resuming the faulting code stream (since
architecturally this isn't a fault, but an abort).
Note that this slightly depends on the previously submitted patch
adjusting the prototype of notify_die() (a compiler warning will result
without that other patch).
AK: Removed obsolete CONFIG_CHECKING code, added comments
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This adjusts things so that handlers of the die() notifier will have
sufficient information about the trap currently being handled. It also
adjusts the notify_die() prototype to (again) match that of i386.
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Other than apparently commonly assumed, the bound instruction does not
require the corresponding IDT entry to have DPL 3.
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
As a follow-up to the introduction of CONFIG_UNWIND_INFO, this
separates the generation of frame unwind information for x86-64 from
that of full debug information.
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Based on the documentation recently posted by Richard Brunner.
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
arch: Use <linux/capability.h> where capable() is used.
Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
There is a window where a probe gets removed right after the probe is hit
on some different cpu. In this case probe handlers can't find a matching
probe instance related to break address. In this case we need to read the
original instruction at break address to see if that is not a break/int3
instruction and recover safely.
Previous code had a bug where we were not checking for the above race in
case of reentrant probes and the below patch fixes this race.
Tested on IA64, Powerpc, x86_64.
Signed-off-by: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The following patch (against 2.6.15-rc5-mm3) fixes a kprobes build break
due to changes introduced in the kprobe locking in 2.6.15-rc5-mm3. In
addition, the patch reverts back the open-coding of kprobe_mutex.
Signed-off-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Acked-by: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Currently arch_remove_kprobes() is only implemented/required for x86_64 and
powerpc. All other architecture like IA64, i386 and sparc64 implementes a
dummy function which is being called from arch independent kprobes.c file.
This patch removes the dummy functions and replaces it with
#define arch_remove_kprobe(p, s) do { } while(0)
Signed-off-by: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Based on some feedback from Oleg Nesterov, I have made few changes to
previously posted patch.
Signed-off-by: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Since Kprobes runtime exception handlers is now lock free as this code path is
now using RCU to walk through the list, there is no need for the
register/unregister{_kprobe} to use spin_{lock/unlock}_isr{save/restore}. The
serialization during registration/unregistration is now possible using just a
mutex.
In the above process, this patch also fixes a minor memory leak for x86_64 and
powerpc.
Signed-off-by: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
These days ioctl32.h is only used for communication of fs/compat.c and
fs/compat_ioctl.c and doesn't contain anything of interest to drivers.
Remove inclusion in various drivers.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
- Moving the crash_dump.c file to arch dependent part as kmap_atomic_pfn is
specific to i386 and highmem may not exist in other archs.
- Use ioremap for x86_64 to map the previous kernel memory.
- In copy_oldmem_page(), we now directly copy to the user/kernel buffer and
avoid the unneccesary copy to a kmalloc'd page.
Signed-off-by: Rachita Kothiyal <rachita@in.ibm.com>
Signed-off-by: Vivek Goyal <vgoyal@in.ibm.com>
Cc: Andi Kleen <ak@muc.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
- Saving the cpu registers of all cpus before booting in to the crash
kernel.
- crash_setup_regs will save the registers of the cpu on which panic has
occured. One of the concerns ppc64 folks raised is that after capturing the
register states, one should not pop the current call frame and push new one.
Hence it has been inlined. More call frames later get pushed on to stack
(machine_crash_shutdown() and machine_kexec()), but one will not want to
backtrace those.
- Not very sure about the CFI annotations. With this patch I am getting
decent backtrace with gdb. Assuming, compiler has generated enough
debugging information for crash_kexec(). Coding crash_setup_regs() in pure
assembly makes it tricky because then it can not be inlined and we don't
want to return back after capturing register states we don't want to pop
this call frame.
- Saving the non-panicing cpus registers will be done in the NMI handler
while shooting down them in machine_crash_shutdown.
- Introducing CRASH_DUMP option in Kconfig for x86_64.
Signed-off-by: Murali M Chakravarthy <muralim@in.ibm.com>
Signed-off-by: Vivek Goyal <vgoyal@in.ibm.com>
Cc: Andi Kleen <ak@muc.de>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
)
From: Vivek Goyal <vgoyal@in.ibm.com>
- Implementing the machine_crash_shutdown for x86_64 which will be called by
crash_kexec (called in case of a panic, sysrq etc.). Here we do things
similar to i386. Disable the interrupts, shootdown the cpus and shutdown
LAPIC and IOAPIC.
Changes in this version:
- As the Eric's APIC initialization patches are reverted back, reintroducing
LAPIC and IOAPIC shutdown.
- Added some comments on CPU hotplug, modified code as suggested by Andi
kleen.
Signed-off-by: Murali M Chakravarthy <muralim@in.ibm.com>
Signed-off-by: Vivek Goyal <vgoyal@in.ibm.com>
Cc: Andi Kleen <ak@muc.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
- elfcorehdr= specifies the location of elf core header stored by the
crashed kernel. This command line option will be passed by the kexec-tools
to capture kernel.
Changes in this version :
- Added more comments in kernel-parameters.txt and in code.
Signed-off-by: Murali M Chakravarthy <muralim@in.ibm.com>
Signed-off-by: Vivek Goyal <vgoyal@in.ibm.com>
Cc: Andi Kleen <ak@muc.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
)
From: Vivek Goyal <vgoyal@in.ibm.com>
- This patch introduces the memmap option for x86_64 similar to i386.
- memmap=exactmap enables setting of an exact E820 memory map, as specified
by the user.
Changes in this version:
- Used e820_end_of_ram() to find the max_pfn as suggested by Andi kleen.
- removed PFN_UP & PFN_DOWN macros
- Printing the user defined map also.
Signed-off-by: Murali M Chakravarthy <muralim@in.ibm.com>
Signed-off-by: Hariprasad Nellitheertha <nharipra@gmail.com>
Signed-off-by: Vivek Goyal <vgoyal@in.ibm.com>
Cc: Andi Kleen <ak@muc.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
- In case of system crash, current state of cpu registers is saved in memory
in elf note format. So far memory for storing elf notes was being allocated
statically for NR_CPUS.
- This patch introduces dynamic allocation of memory for storing elf notes.
It uses alloc_percpu() interface. This should lead to better memory usage.
- Introduced based on Andi Kleen's and Eric W. Biederman's suggestions.
- This patch also moves memory allocation for elf notes from architecture
dependent portion to architecture independent portion. Now crash_notes is
architecture independent. The whole idea is that size of memory to be
allocated per cpu (MAX_NOTE_BYTES) can be architecture dependent and
allocation of this memory can be architecture independent.
Signed-off-by: Vivek Goyal <vgoyal@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch moves the rtc_interrupt() prototype to rtc.h and removes the
prototypes from C files.
It also renames static rtc_interrupt() functions in
arch/arm/mach-integrator/time.c and arch/sh64/kernel/time.c to avoid compile
problems.
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Paul Gortmaker <p_gortmaker@yahoo.com>
Acked-by: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
____cacheline_maxaligned_in_smp is currently used to align critical structures
and avoid false sharing. It uses per-arch L1_CACHE_SHIFT_MAX and people find
L1_CACHE_SHIFT_MAX useless.
However, we have been using ____cacheline_maxaligned_in_smp to align
structures on the internode cacheline size. As per Andi's suggestion,
following patch kills ____cacheline_maxaligned_in_smp and introduces
INTERNODE_CACHE_SHIFT, which defaults to L1_CACHE_SHIFT for all arches.
Arches needing L3/Internode cacheline alignment can define
INTERNODE_CACHE_SHIFT in the arch asm/cache.h. Patch replaces
____cacheline_maxaligned_in_smp with ____cacheline_internodealigned_in_smp
With this patch, L1_CACHE_SHIFT_MAX can be killed
Signed-off-by: Ravikiran Thirumalai <kiran@scalex86.org>
Signed-off-by: Shai Fultheim <shai@scalex86.org>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
With physical CPU hotplug, the CPU is hot removed and it should not receive
any interrupts. Disabling interrupt is much safer. This basically is what we
do in ia64 & x86.
Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Cc: Andi Kleen <ak@muc.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Mark some key kernel datastructures readonly. This patch was previously
posted on Jun 28th but was back then not merged because nothing was enforcing
rodata anyway.. well that changed now :)
Patch by Christoph Lameter <christoph@lameter.com> and Dave Jones
<davej@redhat.com>
Signed-off-by: Arjan van de Ven <arjan@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: Andi Kleen <ak@muc.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Use the #define for ACPI_LEVEL_SENSITIVE instead of assuming
non-zero, because ACPICA 20051021 changes its value to zero.
Also, use uniform variable names:
edge_level -> triggering
active_high_low -> polarity
Signed-off-by: Len Brown <len.brown@intel.com>
On systems that do not support the HPET legacy functions (basically the IBM
x460, but there could be others), in time_init() we accidentally fall into a
PM timer conditional and set the vxtime_hz value to the PM timer's frequency.
We then use this value with the HPET for timekeeping.
This patch (which mimics the behavior in time_init_gtod) corrects the
collision.
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Disabling LAPIC timer isn't sufficient. In some situations, such as we
enabled NMI watchdog, there is still unexpected interrupt (such as NMI)
invoked in offline CPU. This also avoids offline CPU receives spurious
interrupt and anything similar.
Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Acked-by: "Seth, Rohit" <rohit.seth@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Otherwise TSC->HPET fallback could see incorrect state and crash later.
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
When multiple probes are registered at the same address and if due to some
recursion (probe getting triggered within a probe handler), we skip calling
pre_handlers and just increment nmissed field.
The below patch make sure it walks the list for multiple probes case.
Without the below patch we get incorrect results of nmissed count for
multiple probe case.
Signed-off-by: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Completed a major overhaul of the Resource Manager code -
specifically, optimizations in the area of the AML/internal
resource conversion code. The code has been optimized to
simplify and eliminate duplicated code, CPU stack use has
been decreased by optimizing function parameters and local
variables, and naming conventions across the manager have
been standardized for clarity and ease of maintenance (this
includes function, parameter, variable, and struct/typedef
names.)
All Resource Manager dispatch and information tables have
been moved to a single location for clarity and ease of
maintenance. One new file was created, named "rsinfo.c".
The ACPI return macros (return_ACPI_STATUS, etc.) have
been modified to guarantee that the argument is
not evaluated twice, making them less prone to macro
side-effects. However, since there exists the possibility
of additional stack use if a particular compiler cannot
optimize them (such as in the debug generation case),
the original macros are optionally available. Note that
some invocations of the return_VALUE macro may now cause
size mismatch warnings; the return_UINT8 and return_UINT32
macros are provided to eliminate these. (From Randy Dunlap)
Implemented a new mechanism to enable debug tracing for
individual control methods. A new external interface,
acpi_debug_trace(), is provided to enable this mechanism. The
intent is to allow the host OS to easily enable and disable
tracing for problematic control methods. This interface
can be easily exposed to a user or debugger interface if
desired. See the file psxface.c for details.
acpi_ut_callocate() will now return a valid pointer if a
length of zero is specified - a length of one is used
and a warning is issued. This matches the behavior of
acpi_ut_allocate().
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
What is the value shown in "cpu MHz" of /proc/cpuinfo when CPUs are capable of
changing frequency?
Today the answer is: It depends.
On i386:
SMP kernel - It is always the boot frequency
UP kernel - Scales with the frequency change and shows that was last set.
On x86_64:
There is one single variable cpu_khz that gets written by all the CPUs. So,
the frequency set by last CPU will be seen on /proc/cpuinfo of all the
CPUs in the system. What you see also depends on whether you have constant_tsc
capable CPU or not.
On ia64:
It is always boot time frequency of a particular CPU that gets displayed.
The patch below changes this to:
Show the last known frequency of the particular CPU, when cpufreq is present. If
cpu doesnot support changing of frequency through cpufreq, then boot frequency
will be shown. The patch affects i386, x86_64 and ia64 architectures.
Signed-off-by: Venkatesh Pallipadi<venkatesh.pallipadi@intel.com>
Signed-off-by: Dave Jones <davej@redhat.com>
Linux invokes the AML _PDC method (Processor Driver Capabilities)
to tell the BIOS what features it can handle. While the ACPI
spec says nothing about the OS invoking _PDC multiple times,
doing so with changing bits seems to hopelessly confuse the BIOS
on multiple platforms up to and including crashing the system.
Factor out the _PDC invocation so Linux invokes it only once.
http://bugzilla.kernel.org/show_bug.cgi?id=5483
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
Fix a bug in kprobes that can cause an Oops or even a crash when a return
probe is installed on one of the following functions: sys_execve,
do_execve, load_*_binary, flush_old_exec, or flush_thread. The fix is to
remove the call to kprobe_flush_task() in flush_thread(). This fix has
been tested on all architectures for which the return-probes feature has
been implemented (i386, x86_64, ppc64, ia64). Please apply.
BACKGROUND
Up to now, we have called kprobe_flush_task() under two situations: when a
task exits, and when it execs. Flushing kretprobe_instances on exit is
correct because (a) do_exit() doesn't return, and (b) one or more
return-probed functions may be active when a task calls do_exit(). Neither
is the case for sys_execve() and its callees.
Initially, the mistaken call to kprobe_flush_task() on exec was harmless
because we put the "real" return address of each active probed function
back in the stack, just to be safe, when we recycled its
kretprobe_instance. When support for ppc64 and ia64 was added, this safety
measure couldn't be employed, and was eventually dropped even for i386 and
x86_64. sys_execve() and its callees were informally blacklisted for
return probes until this fix was developed.
Acked-by: Prasanna S Panchamukhi <prasanna@in.ibm.com>
Signed-off-by: Jim Keniston <jkenisto@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Fix up booting with sparse mem enabled. Otherwise it would just
cause an early PANIC at boot.
Signed-off-by: Bob Picco <bob.picco@hp.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This is needed for large multinode IBM systems which have a sparse
APIC space in clustered mode, fully covering the available 8 bits.
The previous kernels would limit the local APIC number to 127,
which caused it to reject some of the CPUs at boot.
I increased the maximum and shrunk the apic_version array a bit
to make up for that (the version is only 8 bit, so don't need
an full int to store)
Cc: Chris McDermott <lcm@us.ibm.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
CONFIG_CHECKING covered some debugging code used in the early times
of the port. But it wasn't even SMP safe for quite some time
and the bugs it checked for seem to be gone.
This patch removes all the code to verify GS at kernel entry. There
haven't been any new bugs in this area for a long time.
Previously it also covered the sysctl for the page fault tracing.
That didn't make much sense because that code was unconditionally
compiled in. I made that a boot option now because it is typically
only useful at boot.
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The logging for boot errors was turned off because it was broken
on some AMD systems. But give Intel EM64T systems a chance because they are
supposed to be correct there.
The advantage is that there is a chance to actually log uncorrected
machine checks after the reset.
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Keeping this function does not makes sense because it's a copied (and
buggy) copy of sys_time. The only difference is that now.tv_sec (which is
a time_t, i.e. a 64-bit long) is copied (and truncated) into a int
(32-bit).
The prototype is the same (they both take a long __user *), so let's drop
this and redirect it to sys_time (and make sure it exists by defining
__ARCH_WANT_SYS_TIME).
Only disadvantage is that the sys_stime definition is also compiled (may be
fixed if needed by adding a separate __ARCH_WANT_SYS_STIME macro, and
defining it for all arch's defining __ARCH_WANT_SYS_TIME except x86_64).
Acked-by: Andi Kleen <ak@suse.de>
Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Old code could retry for 10 seconds worst time. Only try it
for one second now.
Suggested by Yinghai Lu
Cc: Yinghai.Lu@amd.com
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Fields obtained through cpuid vector 0x1(ebx[16:23]) and
vector 0x4(eax[14:25], eax[26:31]) indicate the maximum values and might not
always be the same as what is available and what OS sees. So make sure
"siblings" and "cpu cores" values in /proc/cpuinfo reflect the values as seen
by OS instead of what cpuid instruction says. This will also fix the buggy BIOS
cases (for example where cpuid on a single core cpu says there are "2" siblings,
even when HT is disabled in the BIOS.
http://bugzilla.kernel.org/show_bug.cgi?id=4359)
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
When they were disabled before (e.g. after a panic) it's better
to keep them off, otherwise followon panics can happen from timer
interrupt handlers etc.
Drawback is that pageup in the console won't work anymore though.
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
They report 40bit, but only have 36bits of physical address space.
This caused problems with setting up the correct masks for MTRR.
CPUID workaround for steppings 0F33h(supporting x86) and 0F34h(supporting x86
and EM64T). Detail info can be found at:
http://download.intel.com/design/Xeon/specupdt/30240216.pdfhttp://download.intel.com/design/Pentium4/specupdt/30235221.pdf
Signed-off-by: Shaohua Li<shaohua.li@intel.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This allows to run 64bit signal handlers in 64bit processes that run small
code snippets in compat mode.
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
With a NR_CPUS==128 kernel with CPU hotplug enabled we would waste 4MB
on per CPU data of all possible CPUs. The reason was that HOTPLUG
always set up possible map to NR_CPUS cpus and then we need to allocate
that much (each per CPU data is roughly ~32k now)
The underlying problem is that ACPI didn't tell us how many hotplug CPUs
the platform supports. So the old code just assumed all, which would
lead to this memory wastage.
This implements some new heuristics:
- If the BIOS specified disabled CPUs in the ACPI/mptables assume they
can be enabled later (this is bending the ACPI specification a bit,
but seems like a obvious extension)
- The user can overwrite it with a new additionals_cpus=NUM option
- Otherwise use half of the available CPUs or 2, whatever is more.
Cc: ashok.raj@intel.com
Cc: len.brown@intel.com
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Adding __initdata_* to asm-generic/sections.h
Replaces a lot of open coded externs in arch/x86_64/*
I had to change __bss_end to __bss_stop to match the other architectures.
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
We should zap the low mappings, as soon as possible, so that we can catch
kernel bugs more effectively. Previously early boot had NULL mapped
and didn't trap on NULL references.
This patch introduces boot_level4_pgt, which will always have low identity
addresses mapped. Druing boot, all the processors will use this as their
level4 pgt. On BP, we will switch to init_level4_pgt as soon as we enter C
code and zap the low mappings as soon as we are done with the usage of
identity low mapped addresses. On AP's we will zap the low mappings as
soon as we jump to C code.
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Ashok Raj <ashok.raj@intel.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Not go from the CPU number to an mapping array.
Mode number is often used now in fast paths.
This also adds a generic numa_node_id to all the topology includes
Suggested by Eric Dumazet
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Fix
arch/x86_64/kernel/aperture.c: In function #iommu_hole_init#:
arch/x86_64/kernel/aperture.c:199: warning: #aper_order# may be used uninitialized in this function
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
According to cpuid instruction in IA32 SDM-Vol2, when computing cpu model,
we need to consider extended model ID for family 0x6 also.
AK: Also added fixes/simplifcation from Petr Vandrovec
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Remove duplicate __cpuinit in smp.c. Already defined in init.h which is
already included.
Signed-off-by: Ashok Raj <ashok.raj@intel.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Here's a patch that builds on Natalie Protasevich's IRQ compression
patch and tries to work for MPS boots as well as ACPI. It is meant for
a 4-node IBM x460 NUMA box, which was dying because it had interrupt
pins with GSI numbers > NR_IRQS and thus overflowed irq_desc.
The problem is that this system has 270 GSIs (which are 1:1 mapped with
I/O APIC RTEs) and an 8-node box would have 540. This is much bigger
than NR_IRQS (224 for both i386 and x86_64). Also, there aren't enough
vectors to go around. There are about 190 usable vectors, not counting
the reserved ones and the unused vectors at 0x20 to 0x2F. So, my patch
attempts to compress the GSI range and share vectors by sharing IRQs.
Cc: "Protasevich, Natalie" <Natalie.Protasevich@unisys.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
MC4_MISC - DRAM Errors Threshold Register realized under AMD K8 Rev F.
This register is used to count correctable and uncorrectable ECC errors that occur during DRAM read operations.
The user may interface through sysfs files in order to change the threshold configuration.
bank%d/error_count - reads current error count, write to clear.
bank%d/interrupt_enable - set/clear interrupt enable.
bank%d/threshold_limit - read/write the threshold limit.
APIC vector 0xF9 in hw_irq.h.
5 software defined bank ids in mce.h.
new apic.c function to setup threshold apic lvt.
defaults to interrupt off, count enabled, and threshold limit max.
sysfs interface created on /sys/devices/system/threshold.
AK: added some ifdefs to make it compile on UP
Signed-off-by: Jacob Shin <jacob.shin@amd.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
attached patch renames one instance of
/sys/devices/system/timer
to
/sys/devices/system/timer_pit
to avoid a name clash with another instance created in time.c.
Acked-by: Andi Kleen <ak@muc.de>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Make some changes to the NEED_RESCHED and POLLING_NRFLAG to reduce
confusion, and make their semantics rigid. Improves efficiency of
resched_task and some cpu_idle routines.
* In resched_task:
- TIF_NEED_RESCHED is only cleared with the task's runqueue lock held,
and as we hold it during resched_task, then there is no need for an
atomic test and set there. The only other time this should be set is
when the task's quantum expires, in the timer interrupt - this is
protected against because the rq lock is irq-safe.
- If TIF_NEED_RESCHED is set, then we don't need to do anything. It
won't get unset until the task get's schedule()d off.
- If we are running on the same CPU as the task we resched, then set
TIF_NEED_RESCHED and no further action is required.
- If we are running on another CPU, and TIF_POLLING_NRFLAG is *not* set
after TIF_NEED_RESCHED has been set, then we need to send an IPI.
Using these rules, we are able to remove the test and set operation in
resched_task, and make clear the previously vague semantics of
POLLING_NRFLAG.
* In idle routines:
- Enter cpu_idle with preempt disabled. When the need_resched() condition
becomes true, explicitly call schedule(). This makes things a bit clearer
(IMO), but haven't updated all architectures yet.
- Many do a test and clear of TIF_NEED_RESCHED for some reason. According
to the resched_task rules, this isn't needed (and actually breaks the
assumption that TIF_NEED_RESCHED is only cleared with the runqueue lock
held). So remove that. Generally one less locked memory op when switching
to the idle thread.
- Many idle routines clear TIF_POLLING_NRFLAG, and only set it in the inner
most polling idle loops. The above resched_task semantics allow it to be
set until before the last time need_resched() is checked before going into
a halt requiring interrupt wakeup.
Many idle routines simply never enter such a halt, and so POLLING_NRFLAG
can be always left set, completely eliminating resched IPIs when rescheduling
the idle task.
POLLING_NRFLAG width can be increased, to reduce the chance of resched IPIs.
Signed-off-by: Nick Piggin <npiggin@suse.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Con Kolivas <kernel@kolivas.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Run idle threads with preempt disabled.
Also corrected a bugs in arm26's cpu_idle (make it actually call schedule()).
How did it ever work before?
Might fix the CPU hotplugging hang which Nigel Cunningham noted.
We think the bug hits if the idle thread is preempted after checking
need_resched() and before going to sleep, then the CPU offlined.
After calling stop_machine_run, the CPU eventually returns from preemption and
into the idle thread and goes to sleep. The CPU will continue executing
previous idle and have no chance to call play_dead.
By disabling preemption until we are ready to explicitly schedule, this bug is
fixed and the idle threads generally become more robust.
From: alexs <ashepard@u.washington.edu>
PPC build fix
From: Yoichi Yuasa <yuasa@hh.iij4u.or.jp>
MIPS build fix
Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Yoichi Yuasa <yuasa@hh.iij4u.or.jp>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
EXPORT_SYMBOL's for phys_proc_id and cpu_core_id were added this year but
never used.
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Reorganize the preempt_disable/enable calls to eliminate the extra preempt
depth. Changes based on Paul McKenney's review suggestions for the kprobes
RCU changeset.
Signed-off-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Signed-off-by: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Changes to the arch kprobes infrastructure to take advantage of the locking
changes introduced by usage of RCU for synchronization. All handlers are now
run without any locks held, so they have to be re-entrant or provide their own
synchronization.
Signed-off-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Signed-off-by: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
x86_64 changes to track kprobe execution on a per-cpu basis. We now track the
kprobe state machine independently on each cpu using a arch specific kprobe
control block.
Signed-off-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Signed-off-by: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The following set of patches are aimed at improving kprobes scalability. We
currently serialize kprobe registration, unregistration and handler execution
using a single spinlock - kprobe_lock.
With these changes, kprobe handlers can run without any locks held. It also
allows for simultaneous kprobe handler executions on different processors as
we now track kprobe execution on a per processor basis. It is now necessary
that the handlers be re-entrant since handlers can run concurrently on
multiple processors.
All changes have been tested on i386, ia64, ppc64 and x86_64, while sparc64
has been compile tested only.
The patches can be viewed as 3 logical chunks:
patch 1: Reorder preempt_(dis/en)able calls
patches 2-7: Introduce per_cpu data areas to track kprobe execution
patches 8-9: Use RCU to synchronize kprobe (un)registration and handler
execution.
Thanks to Maneesh Soni, James Keniston and Anil Keshavamurthy for their
review and suggestions. Thanks again to Anil, Hien Nguyen and Kevin Stafford
for testing the patches.
This patch:
Reorder preempt_disable/enable() calls in arch kprobes files in preparation to
introduce locking changes. No functional changes introduced by this patch.
Signed-off-by: Ananth N Mavinakayahanalli <ananth@in.ibm.com>
Signed-off-by: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The sys_ptrace boilerplate code (everything outside the big switch
statement for the arch-specific requests) is shared by most architectures.
This patch moves it to kernel/ptrace.c and leaves the arch-specific code as
arch_ptrace.
Some architectures have a too different ptrace so we have to exclude them.
They continue to keep their implementations. For sh64 I had to add a
sh64_ptrace wrapper because it does some initialization on the first call.
For um I removed an ifdefed SUBARCH_PTRACE_SPECIAL block, but
SUBARCH_PTRACE_SPECIAL isn't defined anywhere in the tree.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Paul Mackerras <paulus@samba.org>
Acked-by: Ralf Baechle <ralf@linux-mips.org>
Acked-By: David Howells <dhowells@redhat.com>
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Reads from an HPET register require a round trip to the south bridge and are
almost as slow as PCI reads. By caching the last value we've written to the
comparator register, we can eliminate all HPET reads from the fast path in the
emulated RTC interrupt handler.
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Acked-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Make sure that the RTC timer is in non-periodic mode; some stupid BIOS might
have initialized it to periodic mode.
Furthermore, don't set the SETVAL bit in the config register. This wouldn't
have any effect unless the timer was in period mode (which it isn't), and then
the actual timer frequency would be half that of the desired one because
incrementing the comparator in the interrupt handler would be done after the
hardware has already incremented it itself.
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Acked-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
When the emulated RTC interrupt is no longer needed, we better disable it;
otherwise, we get a spurious interrupt whenever the timer has rolled over and
reaches the same comparator value.
Having a superfluous interrupt every five minutes doesn't hurt much, but it's
bad style anyway. ;-)
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Acked-by: "Pallipadi, Venkatesh" <venkatesh.pallipadi@intel.com>
Cc: Andi Kleen <ak@muc.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Define jiffies_64 in kernel/timer.c rather than having 24 duplicated
defines in each architecture.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Every user of init_timer() also needs to initialize ->function and ->data
fields. This patch adds a simple setup_timer() helper for that.
The schedule_timeout() is patched as an example of usage.
Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The following patch makes swsusp use the PG_nosave and PG_nosave_free flags to
mark pages that should be freed in case of an error during resume.
This allows us to simplify the code and to use swsusp_free() in all of the
swsusp's resume error paths, which makes them actually work.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
If VMX feature is available in the CPU, this patch will make it visible in
the /proc/cpuinfo with the cpuid detection.
Signed-Off-By: Nitin A Kamble <nitin.a.kamble@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
mxcsr_feature_mask_init isn't needed in suspend/resume time (we can use
boot time mask). And actually it's harmful, as it clear task's saved
fxsave in resume. This bug is widely seen by users using zsh.
(akpm: my eyes. Fixed some surrounding whitespace mess)
Signed-off-by: Shaohua Li<shaohua.li@intel.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Andi Kleen <ak@muc.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
I just found out that some precision is unnecessarily lost in the
arch/i386/kernel/timers/timer_tsc.c:set_cyc2ns_scale function. It uses a
cpu_mhz parameter when it could use a cpu_khz. In the specific case of an
Intel P4 running at 3001.171 Mhz, the truncation to 3001 Mhz leads to an
imprecision of 19 microseconds per second : this is very sad for a timer with
nearly nanosecond accuracy.
Fix the x86_64 architecture too.
Cc: george anzinger <george@mvista.com>
Cc: john stultz <johnstul@us.ibm.com>
Cc: Andi Kleen <ak@muc.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
changes to swiotlb.c made in commit 281dd25cdc
since this file has been moved from arch/ia64/lib/swiotlb.c to
lib/swiotlb.c
Signed-off-by: Tony Luck <tony.luck@intel.com>
CPU hotplug fills up the possible map to NR_CPUs, but it did that after
setting up per CPU data. This lead to CPU data not getting allocated
for all possible CPUs, which lead to various side effects.
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The following patch makes swsusp avoid the possible temporary corruption
of page translation tables during resume on x86-64. This is achieved by
creating a copy of the relevant page tables that will not be modified by
swsusp and can be safely used by it on resume.
The problem is that during resume on x86-64 swsusp may temporarily
corrupt the page tables used for the direct mapping of RAM. If that
happens, a page fault occurs and cannot be handled properly, which leads
to the solid hang of the affected system. This leads to the loss of the
system's state from before suspend and may result in the loss of data or
the corruption of filesystems, so it is a serious issue. Also, it
appears to happen quite often (for me, as often as 50% of the time).
The problem is related to the fact that (at least) one of the PMD
entries used in the direct memory mapping (starting at PAGE_OFFSET)
points to a page table the physical address of which is much greater
than the physical address of the PMD entry itself. Moreover,
unfortunately, the physical address of the page table before suspend
(i.e. the one stored in the suspend image) happens to be different to
the physical address of the corresponding page table used during resume
(i.e. the one that is valid right before swsusp_arch_resume() in
arch/x86_64/kernel/suspend_asm.S is executed). Thus while the image is
restored, the "offending" PMD entry gets overwritten, so it does not
point to the right physical address any more (i.e. there's no page
table at the address pointed to by it, because it points to the address
the page table has been at during suspend). Consequently, if the PMD
entry is used later on, and it _is_ used in the process of copying the
image pages, a page fault occurs, but it cannot be handled in the normal
way and the system hangs.
In principle we can call create_resume_mapping() from
swsusp_arch_resume() (ie. from suspend_asm.S), but then the memory
allocations in create_resume_mapping(), resume_pud_mapping(), and
resume_pmd_mapping() must be made carefully so that we use _only_
NosaveFree pages in them (the other pages are overwritten by the loop in
swsusp_arch_resume()). Additionally, we are in atomic context at that
time, so we cannot use GFP_KERNEL. Moreover, if one of the allocations
fails, we should free all of the allocated pages, so we need to trace
them somehow.
All of this is done in the appended patch, except that the functions
populating the page tables are located in arch/x86_64/kernel/suspend.c
rather than in init.c. It may be done in a more elegan way in the
future, with the help of some swsusp patches that are in the works now.
[AK: move some externs into headers, renamed a function]
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Drop global bit from early low mappings
Suggested by Linus, originally also proposed by Suresh.
This fixes a race condition with early start of udev, originally
tracked down by Suresh B. Siddha. The problem was that switching
to the user space VM would not clear the global low mappings
for the beginning of memory, which lead to memory corruption.
Drop the global bits.
The kernel mapping stays global because it should stay constant.
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2.6.14-rc2 does not assign cpus to proper nodeids on our em64t numa boxen.
Our boxes use acpi srat for parsing the numa information.
srat_detect_node() used phys_proc_id[] to get to the cpu's local apic id,
but phys_proc_id[] represents the cpu<->initial_apic_id mapping. The
following patch fixes this problem. Now apicid_to_node[] is properly
indexed with the local apic id.
Signed-off-by: Ravikiran Thirumalai <kiran@scalex86.org>
Acked-by: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Andi Kleen <ak@muc.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The up()/down() orders are incorrect in arch/x86_64/kprobes.c file.
kprobe_mutext is used to protect the free kprobe instruction slot list.
arch_prepare_kprobe applies for a slot from the free list, and
arch_remove_kprobe returns a slot to the free list. The incorrect up()/down()
orders to operate on kprobe_mutex fail to protect the free list. If 2 threads
try to get/return kprobe instruction slot at the same time, the free slot list
might be broken, or a free slot might be applied by 2 threads.
Signed-off-by: Zhang Yanmin <Yanmin.zhang@intel.com>
Cc: Andi Kleen <ak@muc.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The attempt to fixup the lockless mce log buffer introduced an infinite loop
when trying to find a free entry.
And:
Using rcu_dereference() to load mcelog.next doesn't seem to be sufficient
enough to ensure that mcelog.next is loaded each time around the loop in
mce_log(). Instead, use an explicit rmb() to ensure that the compiler gets it
right.
AK: turned the smp_wmbs into true wmbs to make sure they are not
reordered by the compiler on UP.
Signed-off-by: Mike Waychison <mikew@google.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
I checked with AMD and they requested to only disable it for family 15.
Also disable it for i386 too. And some style fixes.
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The swiotlb implementation is shared by both IA-64 and EM64T. However,
the source itself lives under arch/ia64. This patch moves swiotlb.c
from arch/ia64/lib to lib/ and fixes-up the appropriate Makefile and
Kconfig files. No actual changes are made to swiotlb.c.
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
This should resolve the issue seen in bugme bug #5105, where it is assumed
that dualcore x86_64 systems have synced TSCs. This is not the case, and
alternate timesources should be used instead.
For more details, see:
http://bugzilla.kernel.org/show_bug.cgi?id=5105
Andi's earlier concerns that the TSCs should be synced on dualcore systems
have been resolved by confirmation from AMD folks that they can be
unsynced.
Acked-by: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
They seem to have been due to AMD errata 63/122; the fix is to disable
TLB flush filtering in SMP configurations.
Confirmed to fix the problem by Andrew Walrond <andrew@walrond.org>
[ Let's see if we'll have a better fix eventually, this is the Q&D
"let's get this fixed and out there" version ]
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Several implementations were essentialy a common piece of C code using
the cmpxchg() macro. Put the implementation in one spot that everyone
can share, and convert sparc64 over to using this.
Alpha is the lone arch-specific implementation, which codes up a
special fast path for the common case in order to avoid GP reloading
which a pure C version would require.
Signed-off-by: David S. Miller <davem@davemloft.net>
Commit 66759a01ad introduced the fix for
time ticking too fast on some boards by disabling one of the doubly
connected timer pins on ATI boards.
However, it ends up being _much_ too broad a brush, and that just makes
some other ATI boards not work at all since they now have no timer
source.
So disable the automatic ATI southbridge detection, and just rely on
people who see this problem disabling it by hand with the option
"disable_timer_pin_1" on the kernel command line.
Maybe somebody can figure out the proper tests at a later date.
Acked-by: Peter Osterlund <petero2@telia.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Like previously done for i386, get the x86_64 watchdog tick calculation
into a state where it can also be used on CPUs with frequencies beyond
4GHz.
Signed-off-by: Jan Beulich <jbeulich@novell.com>
Acked-by: Andi Kleen <ak@muc.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Use the add_taint() interface for setting tainted bit flags instead of
doing it manually.
Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Original patch from Bertro Simul
This is probably still not quite correct, but seems to be
the best solution so far.
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
As mentioned before, the size of the bug frame can be further reduced while
continuing to use instructions to encode the information.
Signed-off-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
... and with that all instances in arch/x86_64 are gone.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This is the same patch that went into i386 just before 2.6.13
came out. I still can't build 64-bit user apps, so I tested
with program (see below) in 32-bit mode on 64-bit kernel:
Before:
$ fpsig
handler: nr = 8, si = 0x0804bc90, vuc = 0x0804bd10
handler: altstack is at 0x0804b000, ebp = 0x0804bc7c
handler: si_signo = 8, si_errno = 0, si_code = 0 [unknown]
handler: fpu cwd = 0xb40, fpu swd = 0xbaa0
handler: i387 unmasked precision exception, rounded up
After:
$ fpsig
handler: nr = 8, si = 0x0804bc90, vuc = 0x0804bd10
handler: altstack is at 0x0804b000, ebp = 0x0804bc7c
handler: si_signo = 8, si_errno = 0, si_code = 6 [inexact result]
handler: fpu cwd = 0xb40, fpu swd = 0xbaa0
handler: i387 unmasked precision exception, rounded up
Signed-off-by: Chuck Ebbert <76306.1226@compuserve.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The x86_64 nmi code is missing a newline in one of its messages.
I added a space before the CPU id for readability and killed the trailing
space on the previous line as well.
Signed-off-by: Chuck Ebbert <76306.1226@compuserve.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
