Impact: fix missing CPUs in /proc/cpuinfo after CPU hotunplug/hotreplug
In my test, I found that if a cpu has been offline,
the next cpus may not be shown in the /proc/cpuinfo.
if one read() cannot consume the whole /proc/cpuinfo,
c_start() will be called again in the next read() calls.
And *pos has been increased by 1 by the caller(seq_read()).
if this time the cpu#*pos is offline, c_start() will return
NULL, and the next cpus can not be shown.
this fix use next_cpu_nr(*pos - 1, cpu_online_map) to
search the next unshown cpu.
the most easy way to reproduce this bug:
1) offline cpu#1 (cpu#0 is online)
2) dd ibs=2 if=/proc/cpuinfo
the result is that only cpu#0 is shown.
cpu#2 and cpu#3 .... cannot be shown in /proc/cpuinfo
it's bug.
Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This merges branches irq/genirq, irq/sparseirq-v4, timers/hpet-percpu
and x86/uv.
The sparseirq branch is just preliminary groundwork: no sparse IRQs are
actually implemented by this tree anymore - just the new APIs are added
while keeping the old way intact as well (the new APIs map 1:1 to
irq_desc[]). The 'real' sparse IRQ support will then be a relatively
small patch ontop of this - with a v2.6.29 merge target.
* 'genirq-v28-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (178 commits)
genirq: improve include files
intr_remapping: fix typo
io_apic: make irq_mis_count available on 64-bit too
genirq: fix name space collisions of nr_irqs in arch/*
genirq: fix name space collision of nr_irqs in autoprobe.c
genirq: use iterators for irq_desc loops
proc: fixup irq iterator
genirq: add reverse iterator for irq_desc
x86: move ack_bad_irq() to irq.c
x86: unify show_interrupts() and proc helpers
x86: cleanup show_interrupts
genirq: cleanup the sparseirq modifications
genirq: remove artifacts from sparseirq removal
genirq: revert dynarray
genirq: remove irq_to_desc_alloc
genirq: remove sparse irq code
genirq: use inline function for irq_to_desc
genirq: consolidate nr_irqs and for_each_irq_desc()
x86: remove sparse irq from Kconfig
genirq: define nr_irqs for architectures with GENERIC_HARDIRQS=n
...
Update assorted email addresses and related info to point
to a single current, valid address.
additionally
- trivial CREDITS entry updates. (Not that this file means much any more)
- remove arjans dead redhat.com address from powernow driver
Signed-off-by: Dave Jones <davej@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The generated 'capflags.c' file wasn't properly ignored, and the list of
files in scripts/basic/ wasn't up-to-date.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The flag_is_changeable_p() is used by
has_cpuid_p() which can return different results
in the code sequence below:
if (!have_cpuid_p())
identify_cpu_without_cpuid(c);
/* cyrix could have cpuid enabled via c_identify()*/
if (!have_cpuid_p())
return;
Otherwise, the gcc 3.4.6 optimizes these two calls
into one which make the code not working correctly.
Cyrix cpus have the CPUID instruction enabled before
the second call to the have_cpuid_p() but
it is not detected due to the gcc optimization.
Thus the ARR registers (mtrr like) are not detected
on such a cpu.
Signed-off-by: Krzysztof Helt <krzysztof.h1@wp.pl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Take it out of time initialization and move it to
cpu detection time.
Signed-off-by: Glauber Costa <glommer@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Some CPUs have vendor string in the middle of model_id instead of beginning
Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
* 'x86-v28-for-linus-phase4-D' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (186 commits)
x86, debug: print more information about unknown CPUs
x86 setup: handle more than 8 CPU flag words
x86: cpuid, fix typo
x86: move transmeta cap read to early_init_transmeta()
x86: identify_cpu_without_cpuid v2
x86: extended "flags" to show virtualization HW feature in /proc/cpuinfo
x86: move VMX MSRs to msr-index.h
x86: centaur_64.c remove duplicated setting of CONSTANT_TSC
x86: intel.c put workaround for old cpus together
x86: let intel 64-bit use intel.c
x86: make intel_64.c the same as intel.c
x86: make intel.c have 64-bit support code
x86: little clean up of intel.c/intel_64.c
x86: make 64 bit to use amd.c
x86: make amd_64 have 32 bit code
x86: make amd.c have 64bit support code
x86: merge header in amd_64.c
x86: add srat_detect_node for amd64
x86: remove duplicated force_mwait
x86: cpu make amd.c more like amd_64.c v2
...
* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/davej/cpufreq:
[CPUFREQ] Fix BUG: using smp_processor_id() in preemptible code
[CPUFREQ] Don't export governors for default governor
[CPUFREQ][6/6] cpufreq: Add idle microaccounting in ondemand governor
[CPUFREQ][5/6] cpufreq: Changes to get_cpu_idle_time_us(), used by ondemand governor
[CPUFREQ][4/6] cpufreq_ondemand: Parameterize down differential
[CPUFREQ][3/6] cpufreq: get_cpu_idle_time() changes in ondemand for idle-microaccounting
[CPUFREQ][2/6] cpufreq: Change load calculation in ondemand for software coordination
[CPUFREQ][1/6] cpufreq: Add cpu number parameter to __cpufreq_driver_getavg()
[CPUFREQ] use deferrable delayed work init in conservative governor
[CPUFREQ] drivers/cpufreq/cpufreq.c: Adjust error handling code involving cpufreq_cpu_put
[CPUFREQ] add error handling for cpufreq_register_governor() error
[CPUFREQ] acpi-cpufreq: add error handling for cpufreq_register_driver() error
[CPUFREQ] Coding style fixes to arch/x86/kernel/cpu/cpufreq/powernow-k6.c
[CPUFREQ] Coding style fixes to arch/x86/kernel/cpu/cpufreq/elanfreq.c
This merges phase 1 of the x86 tree, which is a collection of branches:
x86/alternatives, x86/cleanups, x86/commandline, x86/crashdump,
x86/debug, x86/defconfig, x86/doc, x86/exports, x86/fpu, x86/gart,
x86/idle, x86/mm, x86/mtrr, x86/nmi-watchdog, x86/oprofile,
x86/paravirt, x86/reboot, x86/sparse-fixes, x86/tsc, x86/urgent and
x86/vmalloc
and as Ingo says: "these are the easiest, purely independent x86 topics
with no conflicts, in one nice Octopus merge".
* 'x86-v28-for-linus-phase1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (147 commits)
x86: mtrr_cleanup: treat WRPROT as UNCACHEABLE
x86: mtrr_cleanup: first 1M may be covered in var mtrrs
x86: mtrr_cleanup: print out correct type v2
x86: trivial printk fix in efi.c
x86, debug: mtrr_cleanup print out var mtrr before change it
x86: mtrr_cleanup try gran_size to less than 1M, v3
x86: mtrr_cleanup try gran_size to less than 1M, cleanup
x86: change MTRR_SANITIZER to def_bool y
x86, debug printouts: IOMMU setup failures should not be KERN_ERR
x86: export set_memory_ro and set_memory_rw
x86: mtrr_cleanup try gran_size to less than 1M
x86: mtrr_cleanup prepare to make gran_size to less 1M
x86: mtrr_cleanup safe to get more spare regs now
x86_64: be less annoying on boot, v2
x86: mtrr_cleanup hole size should be less than half of chunk_size, v2
x86: add mtrr_cleanup_debug command line
x86: mtrr_cleanup optimization, v2
x86: don't need to go to chunksize to 4G
x86_64: be less annoying on boot
x86, olpc: fix endian bug in openfirmware workaround
...
Write the name of the unknown vendor_id to output instead of just
"unknown".
Tag changed to 'vendor_id' as used in /proc/cpuinfo
Signed-off-by: Hans Schou <linux@schou.dk>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Add a cpu parameter to __cpufreq_driver_getavg(). This is needed for software
cpufreq coordination where policy->cpu may not be same as the CPU on which we
want to getavg frequency.
A follow-on patch will use this parameter to getavg freq from all cpus
in policy->cpus.
Change since last patch. Fix the offline/online and suspend/resume
oops reported by Youquan Song <youquan.song@intel.com>
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Dave Jones <davej@redhat.com>
add error handling for cpufreq_register_driver() error
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: cpufreq@lists.linux.org.uk
Signed-off-by: Dave Jones <davej@redhat.com>
Replace the no longer working links and email address in the
documentation and in source code.
Signed-off-by: Márton Németh <nm127@freemail.hu>
Signed-off-by: Dave Jones <davej@redhat.com>
For the purpose of MTRR canonicalization, treat WRPROT as UNCACHEABLE.
Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
The first 1M is don't care when it comes to the variables MTRRs.
Cover it as WB as a heuristic approximation; this is generally what we
want to minimize the number of registers.
Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Print out the correct type when the Write Protected (WP) type is seen.
Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Delay exit to make sure we can actually get the optimal result in as
many cases as possible.
Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
v2: should check with half of range0 size instead of chunk_size
So don't have silly big hole.
in hpa's case we could auto detect instead of adding mtrr_chunk_size in
command line.
Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
add mtrr_cleanup_debug to print out more info about layout
Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Cc: Yinghai Lu <yhlu.kernel@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
change back chunksize max to 2g
otherwise will get strange layout in 2G ram system like
0 - 4g WB, 2040M - 2048M UC, 2048M - 4G NC
instead of
0 - 2g WB, 2040M - 2048M UC
Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Make use of FW_BUG interface to give vendors and users the ability to
automatically check for powernow-k8 related BIOS bugs by:
dmesg |grep "Firmware Bug"
Signed-off-by: Thomas Renninger <trenn@suse.de>
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
There's a small window when NMI watchdog is being set up that if any NMIs
are triggered, the NMI code will make make use of not initalized wd_ops
elements:
void setup_apic_nmi_watchdog(void *unused)
{
if (__get_cpu_var(wd_enabled))
return;
/* cheap hack to support suspend/resume */
/* if cpu0 is not active neither should the other cpus */
if (smp_processor_id() != 0 && atomic_read(&nmi_active) <= 0)
return;
switch (nmi_watchdog) {
case NMI_LOCAL_APIC:
/* enable it before to avoid race with handler */
--> __get_cpu_var(wd_enabled) = 1;
--> if (lapic_watchdog_init(nmi_hz) < 0) {
(...)
asmlinkage notrace __kprobes void default_do_nmi(struct pt_regs *regs)
{
(...)
if (nmi_watchdog_tick(regs, reason))
return;
(...)
notrace __kprobes int
nmi_watchdog_tick(struct pt_regs *regs, unsigned reason)
{
(...)
if (!__get_cpu_var(wd_enabled))
return rc;
switch (nmi_watchdog) {
case NMI_LOCAL_APIC:
rc |= lapic_wd_event(nmi_hz);
(...)
int lapic_wd_event(unsigned nmi_hz)
{
struct nmi_watchdog_ctlblk *wd = &__get_cpu_var(nmi_watchdog_ctlblk);
u64 ctr;
--> rdmsrl(wd->perfctr_msr, ctr);
and wd->*_msr will be initialized on each processor type specific setup, after
enabling NMIs for PMIs. Since the counter was just set, the chances of an
performance counter generated NMI is minimal, but any other unknown NMI would
trigger the problem. This patch fixes the problem by setting everything up
before enabling performance counter generated NMIs and will set wd_enabled
using a callback function.
Signed-off-by: Aristeu Rozanski <aris@redhat.com>
Acked-by: Don Zickus <dzickus@redhat.com>
Acked-by: Prarit Bhargava <prarit@redhat.com>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
P4s have a quirk that makes necessary to clear P4_CCCR_OVF bit on the CCCR
everytime the PMI is triggered. When booting the kernel with reset_devices
(more specific kdump case), the counters reach zero and the PMI will be
generated. This is not a problem on other processors but on P4s, it'll
continue to generate NMIs until that bit is cleared. Since there may be
other users of the performance counters, clear and disable all of them
when booting with reset_devices option.
We have a P4 box here that crashes because of this problem. Since the kdump
kernel usually boots with only one processor active, the second logical
unit won't be set up, therefore, MSR_P4_IQ_CCCR1 (and other performance
counter registers) won't be cleared and P4_CCCR_OVF may be still set because
the previous kernel was using this register. An NMI is triggered because of
the MSR_P4_IQ_CCCR1 right after the NMI delivery is enabled, triggering the
race fixed on my previous email.
Signed-off-by: Aristeu Rozanski <aris@redhat.com>
Acked-by: Don Zickus <dzickus@redhat.com>
Acked-by: Prarit Bhargava <prarit@redhat.com>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
so could help catch attention about bug in bios about mtrr mask setting.
WARN_ONCE got into mainline already, lets use it.
Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
fix this warning reported by Andrew Morton:
> arch/x86/kernel/cpu/mtrr/main.c: In function 'mtrr_bp_init':
> arch/x86/kernel/cpu/mtrr/main.c:1170: warning: 'extra_remove_base' may be used uninitialized in this function
the warning is bogus but the logic that prevents uninitialized use
is a bit convoluted so simplify it all.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Completely disable NOPL on 32 bits. It turns out that Microsoft
Virtual PC is so broken it can't even reliably *fail* in the presence
of NOPL.
This leaves the infrastructure in place but disables it
unconditionally.
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Krzysztof found some old cyrix cpu where an mtrr-alike cpu feature was
not detected properly.
this one is based on Krzysztof' patch, and we call ->c_identify() in
early_identify_cpu.
need to call c_identify() for cpus without cpuid even earlier ...
v2: Krzysztof point out need to give cyrix another chance about cpuid
checking again, after ->c_identify() enables cpuid for it
Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Cc: Krzysztof Helt <krzysztof.h1@wp.pl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
The hardware virtualization technology evolves very fast. But currently
it's hard to tell if your CPU support a certain kind of HW technology
without digging into the source code.
The patch add a new catagory in "flags" under /proc/cpuinfo. Now "flags"
can indicate the (important) HW virtulization features the CPU supported
as well.
Current implementation just cover Intel VMX side.
Signed-off-by: Sheng Yang <sheng.yang@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
consolidate the code some more.
No change in functionality intended.
Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
now that arch/x86/kernel/cpu/intel_64.c and
arch/x86/kernel/cpu/intel.c are equal, drop
arch/x86/kernel/cpu/intel_64.c and fix up
the glue.
Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
No change in functionality intended - this only adds the 32-bit side.
Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
arch/x86/kernel/cpu/amd.c is now 100% identical to
arch/x86/kernel/cpu/amd_64.c, so use amd.c on 64-bit too
and fix up the namespace impact.
Simplify the Kconfig glue as well.
Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
1. make 32bit have early_init_amd_mc and amd_detect_cmp
2. seperate init_amd_k5/k6/k7 ...
v2: fix compiling for !CONFIG_SMP
Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Exception stacks are allocated each time a CPU is set online.
But the allocated space is never freed. Thus with one CPU hotplug
offline/online cycle there is a memory leak of 24K (6 pages) for
a CPU.
Fix is to allocate exception stacks only once -- when the CPU is
set online for the first time.
Signed-off-by: Andreas Herrmann <andreas.herrmann3@amd.com>
Cc: akpm@linux-foundation.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
pda->irqstackptr is allocated whenever a CPU is set online.
But it is never freed. This results in a memory leak of 16K
for each CPU offline/online cycle.
Fix is to allocate pda->irqstackptr only once.
Signed-off-by: Andreas Herrmann <andreas.herrmann3@amd.com>
Cc: akpm@linux-foundation.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Krzysztof Helt found MTRR is not detected on k6-2
root cause:
we moved mtrr_bp_init() early for mtrr trimming,
and in early_detect we only read the CPU capability from cpuid,
so some cpu doesn't have that bit in cpuid.
So we need to add early_init_xxxx to preset those bit before mtrr_bp_init
for those earlier cpus.
this patch is for v2.6.27
Reported-by: Krzysztof Helt <krzysztof.h1@wp.pl>
Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Move early cpu initialization after cpu early get cap so the
early cpu initialization can fix up cpu caps.
Signed-off-by: Krzysztof Helt <krzysztof.h1@wp.pl>
Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
The long noops ("NOPL") are supposed to be detected by family >= 6.
Unfortunately, several non-Intel x86 implementations, both hardware
and software, don't obey this dictum. Instead, probe for NOPL
directly by executing a NOPL instruction and see if we get #UD.
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Move reset_lazy_tlbstate into tlb_32.c, and define noop versions of
play_dead() in process_{32,64}.c when !CONFIG_SMP.
Signed-off-by: Alex Nixon <alex.nixon@citrix.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Use cpu/common.c on both 64-bit and 32-bit and remove cpu/common_64.c.
We started out with this linecount:
816 arch/x86/kernel/cpu/common_64.c
805 arch/x86/kernel/cpu/common.c
and the resulting common.c is 1197 lines long, so there's already
424 lines of code eliminated in this phase of the unification.
Signed-off-by: Yinghai <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Merge leftover whitespaces, to make arch/x86/kernel/cpu/common_64.c
exactly identical to arch/x86/kernel/cpu/common.c.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
hard to merge by lines... (as here we have material differences between
32-bit and 64-bit mode) - will try to do it later.
Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Move the 32-bit and 64-bit gdt_page definitions next to each
other, separated with an #ifdef.
Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Make the files more similar in preparation to unification, no
code changed.
Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
64-bit has X86_HT set too, so use that instead of SMP.
This also removes a include/asm-x86/processor.h ifdef.
Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
