In kexec jump support, jump back address passed to the kexeced
kernel via function calling ABI, that is, the function call
return address is the jump back entry.
Furthermore, jump back entry == 0 should be used to signal that
the jump back or preserve context is not enabled in the original
kernel.
But in the current implementation the stack position used for
function call return address is not cleared context
preservation is disabled. The patch fixes this bug.
Reported-and-tested-by: Yin Kangkai <kangkai.yin@intel.com>
Signed-off-by: Huang Ying <ying.huang@intel.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: <stable@kernel.org>
Link: http://lkml.kernel.org/r/1310607277-25029-1-git-send-email-ying.huang@intel.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
We need to carve up the configuration between:
- MID general
- Moorestown specific
- Medfield specific
- Future devices
As a base point create an INTEL_MID configuration property. We
make the existing MRST configuration a sub-option. This means
that the rest of the kernel config can still use X86_MRST checks
without anything going backwards.
After this is merged future patches will tidy up which devices
are MID and which are X86_MRST, as well as add options for
Medfield.
Signed-off-by: Alan Cox <alan@linux.intel.com>
Link: http://lkml.kernel.org/r/20110712164859.7642.84136.stgit@bob.linux.org.uk
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This code uses PCI_CLASS_REVISION instead of PCI_REVISION_ID, so
it wasn't converted by commit 44c10138fd4bbc ("PCI: Change all
drivers to use pci_device->revision") before being moved to arch/x86/...
Signed-off-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Cc: Dave Jones <davej@redhat.com>
Link: http://lkml.kernel.org/r/201107111901.39281.sshtylyov@ru.mvista.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
The EFI specification requires that callers of the time related
runtime functions serialize with other CMOS accesses in the
kernel, as the EFI time functions may choose to also use the
legacy CMOS RTC.
Besides fixing a latent bug, this is a prerequisite to safely
enable the rtc-efi driver for x86, which ought to be preferred
over rtc-cmos on all EFI platforms.
Signed-off-by: Jan Beulich <jbeulich@novell.com>
Acked-by: Matthew Garrett <mjg59@srcf.ucam.org>
Cc: <mjg@redhat.com>
Link: http://lkml.kernel.org/r/4E257E33020000780004E319@nat28.tlf.novell.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: Matthew Garrett <mjg@redhat.com>
With CPU hotplug, there is a theoretical race between other CMOS
(namely RTC) accesses and those done in the SMP secondary
processor bringup path.
I am unware of the problem having been noticed by anyone in practice,
but it would very likely be rather spurious and very hard to reproduce.
So to be on the safe side, acquire rtc_lock around those accesses.
Signed-off-by: Jan Beulich <jbeulich@novell.com>
Cc: John Stultz <john.stultz@linaro.org>
Link: http://lkml.kernel.org/r/4E257AE7020000780004E2FF@nat28.tlf.novell.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
With the write lock path simply subtracting RW_LOCK_BIAS there
is, on large systems, the theoretical possibility of overflowing
the 32-bit value that was used so far (namely if 128 or more
CPUs manage to do the subtraction, but don't get to do the
inverse addition in the failure path quickly enough).
A first measure is to modify RW_LOCK_BIAS itself - with the new
value chosen, it is good for up to 2048 CPUs each allowed to
nest over 2048 times on the read path without causing an issue.
Quite possibly it would even be sufficient to adjust the bias a
little further, assuming that allowing for significantly less
nesting would suffice.
However, as the original value chosen allowed for even more
nesting levels, to support more than 2048 CPUs (possible
currently only for 64-bit kernels) the lock itself gets widened
to 64 bits.
Signed-off-by: Jan Beulich <jbeulich@novell.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/4E258E0D020000780004E3F0@nat28.tlf.novell.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Rather than having two functionally identical implementations
for 32- and 64-bit configurations, use the previously extended
assembly abstractions to fold the rwsem two implementations into
a shared one.
Signed-off-by: Jan Beulich <jbeulich@novell.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/4E258DF3020000780004E3ED@nat28.tlf.novell.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Rather than having two functionally identical implementations
for 32- and 64-bit configurations, extend the existing assembly
abstractions enough to fold the two rwlock implementations into
a shared one.
Signed-off-by: Jan Beulich <jbeulich@novell.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/4E258DD7020000780004E3EA@nat28.tlf.novell.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
x86. reboot: Make Dell Latitude E6320 use reboot=pci
x86, doc only: Correct real-mode kernel header offset for init_size
x86: Disable AMD_NUMA for 32bit for now
Singleton calls seem to end up being pretty common, so just
directly call the hypercall rather than going via multicall.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
It's useful - and probably should be a config - but its very heavyweight,
especially with the tracing stuff to help sort out problems.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Make sure the fastpath code is inlined. Batch the page permission change
and the pin/unpin, and make sure that it can be batched with any
adjacent set_pte/pmd/etc operations.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Now that 1b3f2a72bbcfdf92e368a44448c45eb639b05b5e is in, it is very
important that the below lying comment be removed! :-)
Signed-off-by: Borislav Petkov <bp@alien8.de>
Link: http://lkml.kernel.org/r/20110718191054.GA18359@liondog.tnic
Acked-by: Andy Lutomirski <luto@mit.edu>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Fix the printk_once() so that it actually prints (didn't print before
due to a stray comma.)
[ hpa: changed to an incremental patch and adjusted the description
accordingly. ]
Signed-off-by: Len Brown <len.brown@intel.com>
Link: http://lkml.kernel.org/r/alpine.LFD.2.02.1107151732480.18606@x980
Cc: <table@kernel.org>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
handle_signal()->set_fs() has a nice comment which explains what
set_fs() is, but it doesn't explain why it is needed and why it
depends on CONFIG_X86_64.
Afaics, the history of this confusion is:
1. I guess today nobody can explain why it was needed
in arch/i386/kernel/signal.c, perhaps it was always
wrong. This predates 2.4.0 kernel.
2. then it was copy-and-past'ed to the new x86_64 arch.
3. then it was removed from i386 (but not from x86_64)
by b93b6ca3 "i386: remove unnecessary code".
4. then it was reintroduced under CONFIG_X86_64 when x86
unified i386 and x86_64, because the patch above didn't
touch x86_64.
Remove it. ->addr_limit should be correct. Even if it was possible
that it is wrong, it is too late to fix it after setup_rt_frame().
Linus commented in:
http://lkml.kernel.org/r/alpine.LFD.0.999.0707170902570.19166@woody.linux-foundation.org
... about the equivalent bit from i386:
Heh. I think it's entirely historical.
Please realize that the whole reason that function is called "set_fs()" is
that it literally used to set the %fs segment register, not
"->addr_limit".
So I think the "set_fs(USER_DS)" is there _only_ to match the other
regs->xds = __USER_DS;
regs->xes = __USER_DS;
regs->xss = __USER_DS;
regs->xcs = __USER_CS;
things, and never mattered. And now it matters even less, and has been
copied to all other architectures where it is just totally insane.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Link: http://lkml.kernel.org/r/20110710164424.GA20261@redhat.com
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
1. do_signal() looks at TS_RESTORE_SIGMASK and calculates the
mask which should be stored in the signal frame, then it
passes "oldset" to the callees, down to setup_rt_frame().
This is ugly, setup_rt_frame() can do this itself and nobody
else needs this sigset_t. Move this code into setup_rt_frame.
2. do_signal() also clears TS_RESTORE_SIGMASK if handle_signal()
succeeds.
We can move this to setup_rt_frame() as well, this avoids the
unnecessary checks and makes the logic more clear.
3. use set_current_blocked() instead of sigprocmask(SIG_SETMASK),
sigprocmask() should be avoided.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Link: http://lkml.kernel.org/r/20110710182203.GA27979@redhat.com
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
sys_sigsuspend() and sys_sigreturn() change ->blocked directly.
This is not correct, see the changelog in e6fa16ab
"signal: sigprocmask() should do retarget_shared_pending()"
Change them to use set_current_blocked().
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Link: http://lkml.kernel.org/r/20110710192727.GA31759@redhat.com
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
sys32_sigsuspend() and sys32_*sigreturn() change ->blocked directly.
This is not correct, see the changelog in e6fa16ab
"signal: sigprocmask() should do retarget_shared_pending()"
Change them to use set_current_blocked().
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Link: http://lkml.kernel.org/r/20110710192724.GA31755@redhat.com
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Fix a trivial typo in the name of the constant
ENERGY_PERF_BIAS_POWERSAVE. This didn't cause trouble because this
constant is not currently used for anything.
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Cc: Len Brown <len.brown@intel.com>
Link: http://lkml.kernel.org/r/tip-abe48b108247e9b90b4c6739662a2e5c765ed114@git.kernel.org
Instead of hw_nmi_watchdog_set_attr() weak function
and appropriate x86_pmu::hw_watchdog_set_attr() call
we introduce even alias mechanism which allow us
to drop this routines completely and isolate quirks
of Netburst architecture inside P4 PMU code only.
The main idea remains the same though -- to allow
nmi-watchdog and perf top run simultaneously.
Note the aliasing mechanism applies to generic
PERF_COUNT_HW_CPU_CYCLES event only because arbitrary
event (say passed as RAW initially) might have some
additional bits set inside ESCR register changing
the behaviour of event and we can't guarantee anymore
that alias event will give the same result.
P.S. Thanks a huge to Don and Steven for for testing
and early review.
Acked-by: Don Zickus <dzickus@redhat.com>
Tested-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
CC: Ingo Molnar <mingo@elte.hu>
CC: Peter Zijlstra <a.p.zijlstra@chello.nl>
CC: Stephane Eranian <eranian@google.com>
CC: Lin Ming <ming.m.lin@intel.com>
CC: Arnaldo Carvalho de Melo <acme@redhat.com>
CC: Frederic Weisbecker <fweisbec@gmail.com>
Link: http://lkml.kernel.org/r/20110708201712.GS23657@sun
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Since 2.6.36 (23016bf0d25), Linux prints the existence of "epb" in /proc/cpuinfo,
Since 2.6.38 (d5532ee7b40), the x86_energy_perf_policy(8) utility has
been available in-tree to update MSR_IA32_ENERGY_PERF_BIAS.
However, the typical BIOS fails to initialize the MSR, presumably
because this is handled by high-volume shrink-wrap operating systems...
Linux distros, on the other hand, do not yet invoke x86_energy_perf_policy(8).
As a result, WSM-EP, SNB, and later hardware from Intel will run in its
default hardware power-on state (performance), which assumes that users
care for performance at all costs and not for energy efficiency.
While that is fine for performance benchmarks, the hardware's intended default
operating point is "normal" mode...
Initialize the MSR to the "normal" by default during kernel boot.
x86_energy_perf_policy(8) is available to change the default after boot,
should the user have a different preference.
Signed-off-by: Len Brown <len.brown@intel.com>
Link: http://lkml.kernel.org/r/alpine.LFD.2.02.1107140051020.18606@x980
Acked-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Cc: <stable@kernel.org>
This patch makes update_rq_clock() aware of steal time.
The mechanism of operation is not different from irq_time,
and follows the same principles. This lives in a CONFIG
option itself, and can be compiled out independently of
the rest of steal time reporting. The effect of disabling it
is that the scheduler will still report steal time (that cannot be
disabled), but won't use this information for cpu power adjustments.
Everytime update_rq_clock_task() is invoked, we query information
about how much time was stolen since last call, and feed it into
sched_rt_avg_update().
Although steal time reporting in account_process_tick() keeps
track of the last time we read the steal clock, in prev_steal_time,
this patch do it independently using another field,
prev_steal_time_rq. This is because otherwise, information about time
accounted in update_process_tick() would never reach us in update_rq_clock().
Signed-off-by: Glauber Costa <glommer@redhat.com>
Acked-by: Rik van Riel <riel@redhat.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Tested-by: Eric B Munson <emunson@mgebm.net>
CC: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
CC: Anthony Liguori <aliguori@us.ibm.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
This patch adds a function pointer in one of the many paravirt_ops
structs, to allow guests to register a steal time function. Besides
a steal time function, we also declare two jump_labels. They will be
used to allow the steal time code to be easily bypassed when not
in use.
Signed-off-by: Glauber Costa <glommer@redhat.com>
Acked-by: Rik van Riel <riel@redhat.com>
Tested-by: Eric B Munson <emunson@mgebm.net>
CC: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
CC: Peter Zijlstra <peterz@infradead.org>
CC: Anthony Liguori <aliguori@us.ibm.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
To implement steal time, we need the hypervisor to pass the guest
information about how much time was spent running other processes
outside the VM, while the vcpu had meaningful work to do - halt
time does not count.
This information is acquired through the run_delay field of
delayacct/schedstats infrastructure, that counts time spent in a
runqueue but not running.
Steal time is a per-cpu information, so the traditional MSR-based
infrastructure is used. A new msr, KVM_MSR_STEAL_TIME, holds the
memory area address containing information about steal time
This patch contains the hypervisor part of the steal time infrasructure,
and can be backported independently of the guest portion.
[avi, yongjie: export delayacct_on, to avoid build failures in some configs]
Signed-off-by: Glauber Costa <glommer@redhat.com>
Tested-by: Eric B Munson <emunson@mgebm.net>
CC: Rik van Riel <riel@redhat.com>
CC: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
CC: Peter Zijlstra <peterz@infradead.org>
CC: Anthony Liguori <aliguori@us.ibm.com>
Signed-off-by: Yongjie Ren <yongjie.ren@intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
The vread field was bloating struct clocksource everywhere except
x86_64, and I want to change the way this works on x86_64, so let's
split it out into per-arch data.
Cc: x86@kernel.org
Cc: Clemens Ladisch <clemens@ladisch.de>
Cc: linux-ia64@vger.kernel.org
Cc: Tony Luck <tony.luck@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: John Stultz <johnstul@us.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andy Lutomirski <luto@mit.edu>
Link: http://lkml.kernel.org/r/3ae5ec76a168eaaae63f08a2a1060b91aa0b7759.1310563276.git.luto@mit.edu
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Three fixes here:
- Send SIGSEGV if called from compat code or with a funny CS.
- Don't BUG on impossible addresses.
- Add a missing local_irq_disable.
This patch also removes an unused variable.
Signed-off-by: Andy Lutomirski <luto@mit.edu>
Link: http://lkml.kernel.org/r/6fb2b13ab39b743d1e4f466eef13425854912f7f.1310563276.git.luto@mit.edu
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
SPARSEMEM w/o VMEMMAP and DISCONTIGMEM, both used only on 32bit, use
sections array to map pfn to nid which is limited in granularity. If
NUMA nodes are laid out such that the mapping cannot be accurate, boot
will fail triggering BUG_ON() in mminit_verify_page_links().
On 32bit, it's 512MiB w/ PAE and SPARSEMEM. This seems to have been
granular enough until commit 2706a0bf7b (x86, NUMA: Enable
CONFIG_AMD_NUMA on 32bit too). Apparently, there is a machine which
aligns NUMA nodes to 128MiB and has only AMD NUMA but not SRAT. This
led to the following BUG_ON().
On node 0 totalpages: 2096615
DMA zone: 32 pages used for memmap
DMA zone: 0 pages reserved
DMA zone: 3927 pages, LIFO batch:0
Normal zone: 1740 pages used for memmap
Normal zone: 220978 pages, LIFO batch:31
HighMem zone: 16405 pages used for memmap
HighMem zone: 1853533 pages, LIFO batch:31
BUG: Int 6: CR2 (null)
EDI (null) ESI 00000002 EBP 00000002 ESP c1543ecc
EBX f2400000 EDX 00000006 ECX (null) EAX 00000001
err (null) EIP c16209aa CS 00000060 flg 00010002
Stack: f2400000 00220000 f7200800 c1620613 00220000 01000000 04400000 00238000
(null) f7200000 00000002 f7200b58 f7200800 c1620929 000375fe (null)
f7200b80 c16395f0 00200a02 f7200a80 (null) 000375fe 00000002 (null)
Pid: 0, comm: swapper Not tainted 2.6.39-rc5-00181-g2706a0b #17
Call Trace:
[<c136b1e5>] ? early_fault+0x2e/0x2e
[<c16209aa>] ? mminit_verify_page_links+0x12/0x42
[<c1620613>] ? memmap_init_zone+0xaf/0x10c
[<c1620929>] ? free_area_init_node+0x2b9/0x2e3
[<c1607e99>] ? free_area_init_nodes+0x3f2/0x451
[<c1601d80>] ? paging_init+0x112/0x118
[<c15f578d>] ? setup_arch+0x791/0x82f
[<c15f43d9>] ? start_kernel+0x6a/0x257
This patch implements node_map_pfn_alignment() which determines
maximum internode alignment and update numa_register_memblks() to
reject NUMA configuration if alignment exceeds the pfn -> nid mapping
granularity of the memory model as determined by PAGES_PER_SECTION.
This makes the problematic machine boot w/ flatmem by rejecting the
NUMA config and provides protection against crazy NUMA configurations.
Signed-off-by: Tejun Heo <tj@kernel.org>
Link: http://lkml.kernel.org/r/20110712074534.GB2872@htj.dyndns.org
LKML-Reference: <20110628174613.GP478@escobedo.osrc.amd.com>
Reported-and-Tested-by: Hans Rosenfeld <hans.rosenfeld@amd.com>
Cc: Conny Seidel <conny.seidel@amd.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
DISCONTIGMEM on x86-32 implements pfn -> nid mapping similarly to
SPARSEMEM; however, it calls each mapping unit ELEMENT instead of
SECTION. This patch renames it to SECTION so that PAGES_PER_SECTION
is valid for both DISCONTIGMEM and SPARSEMEM. This will be used by
the next patch to implement mapping granularity check.
This patch is trivial constant rename.
Signed-off-by: Tejun Heo <tj@kernel.org>
Link: http://lkml.kernel.org/r/20110712074422.GA2872@htj.dyndns.org
Cc: Hans Rosenfeld <hans.rosenfeld@amd.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
When "apic=debug" is used as a boot parameter, Linux prints the IOAPIC routing
entries in "dmesg". Below is output from IOAPIC whose apic_id is 8:
# dmesg | grep "routing entry"
IOAPIC[8]: Set routing entry (8-1 -> 0x31 -> IRQ 1 Mode:0 Active:0 Dest:0)
IOAPIC[8]: Set routing entry (8-2 -> 0x30 -> IRQ 0 Mode:0 Active:0 Dest:0)
IOAPIC[8]: Set routing entry (8-3 -> 0x33 -> IRQ 3 Mode:0 Active:0 Dest:0)
...
Similarly, when IR (interrupt remapping) is enabled, and the IRTE
(interrupt remapping table entry) is set up we should display it.
After the fix:
# dmesg | grep IRTE
IOAPIC[8]: Set IRTE entry (P:1 FPD:0 Dst_Mode:0 Redir_hint:1 Trig_Mode:0 Dlvry_Mode:0 Avail:0 Vector:31 Dest:00000000 SID:00F1 SQ:0 SVT:1)
IOAPIC[8]: Set IRTE entry (P:1 FPD:0 Dst_Mode:0 Redir_hint:1 Trig_Mode:0 Dlvry_Mode:0 Avail:0 Vector:30 Dest:00000000 SID:00F1 SQ:0 SVT:1)
IOAPIC[8]: Set IRTE entry (P:1 FPD:0 Dst_Mode:0 Redir_hint:1 Trig_Mode:0 Dlvry_Mode:0 Avail:0 Vector:33 Dest:00000000 SID:00F1 SQ:0 SVT:1)
...
The IRTE is defined in Sec 9.5 of the Intel VT-d Specification.
Signed-off-by: Naga Chumbalkar <nagananda.chumbalkar@hp.com>
Link: http://lkml.kernel.org/r/20110712211704.2939.71291.sendpatchset@nchumbalkar.americas.cpqcorp.net
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Somehow we got into a situation where the __this_cpu_xchg() operations were
not defined in the same way as this_cpu_xchg() and friends. I had some build
failures under 32 bit that were addressed by these fixes.
Signed-off-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
