User space can request hardware and/or software time stamping.
Reporting of the result(s) via a new control message is enabled
separately for each field in the message because some of the
fields may require additional computation and thus cause overhead.
User space can tell the different kinds of time stamps apart
and choose what suits its needs.
When a TX timestamp operation is requested, the TX skb will be cloned
and the clone will be time stamped (in hardware or software) and added
to the socket error queue of the skb, if the skb has a socket
associated with it.
The actual TX timestamp will reach userspace as a RX timestamp on the
cloned packet. If timestamping is requested and no timestamping is
done in the device driver (potentially this may use hardware
timestamping), it will be done in software after the device's
start_hard_xmit routine.
Signed-off-by: Patrick Ohly <patrick.ohly@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
* 'timers-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
timers: fix TIMER_ABSTIME for process wide cpu timers
timers: split process wide cpu clocks/timers, fix
x86: clean up hpet timer reinit
timers: split process wide cpu clocks/timers, remove spurious warning
timers: split process wide cpu clocks/timers
signal: re-add dead task accumulation stats.
x86: fix hpet timer reinit for x86_64
sched: fix nohz load balancer on cpu offline
* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
ptrace, x86: fix the usage of ptrace_fork()
i8327: fix outb() parameter order
x86: fix math_emu register frame access
x86: math_emu info cleanup
x86: include correct %gs in a.out core dump
x86, vmi: put a missing paravirt_release_pmd in pgd_dtor
x86: find nr_irqs_gsi with mp_ioapic_routing
x86: add clflush before monitor for Intel 7400 series
x86: disable intel_iommu support by default
x86: don't apply __supported_pte_mask to non-present ptes
x86: fix grammar in user-visible BIOS warning
x86/Kconfig.cpu: make Kconfig help readable in the console
x86, 64-bit: print DMI info in the oops trace
The constraint used for retrieving and restoring the parent function
pointer is incorrect. The parent variable is a pointer, and the
address of the pointer is modified by the asm statement and not
the pointer itself. It is incorrect to pass it in as an output
constraint since the asm will never update the pointer.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: fix to prevent a kernel crash on fault
If for some reason the pointer to the parent function on the
stack takes a fault, the fix up code will not return back to
the original faulting code. This can lead to unpredictable
results and perhaps even a kernel panic.
A fault should not happen, but if it does, we should simply
disable the tracer, warn, and continue running the kernel.
It should not lead to a kernel crash.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
In i8237A_resume(), when resetting the DMA controller, the parameters to
dma_outb() were mixed up.
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
[ cleaned up the file a tiny bit. ]
Signed-off-by: Ingo Molnar <mingo@elte.hu>
do_device_not_available() is the handler for #NM and it declares that
it takes a unsigned long and calls math_emu(), which takes a long
argument and surprisingly expects the stack frame starting at the zero
argument would match struct math_emu_info, which isn't true regardless
of configuration in the current code.
This patch makes do_device_not_available() take struct pt_regs like
other exception handlers and initialize struct math_emu_info with
pointer to it and pass pointer to the math_emu_info to math_emulate()
like normal C functions do. This way, unless gcc makes a copy of
struct pt_regs in do_device_not_available(), the register frame is
correctly accessed regardless of kernel configuration or compiler
used.
This doesn't fix all math_emu problems but it at least gets it
somewhat working.
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
* 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/davej/cpufreq:
[CPUFREQ] powernow-k8: Get transition latency from ACPI _PSS table
[CPUFREQ] Make ignore_nice_load setting of ondemand work as expected.
Architectures other than mips and x86 are not using ticket spinlocks.
Therefore, the contention on the lock is meaningless, since there is
nobody known to be waiting on it (arguably /fairly/ unfair locks).
Dummy it out to return 0 on other architectures.
Signed-off-by: Kyle McMartin <kyle@redhat.com>
Acked-by: Ralf Baechle <ralf@linux-mips.org>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Impact: cleanup
* Come on, struct info? s/struct info/struct math_emu_info/
* Use struct pt_regs and kernel_vm86_regs instead of defining its own
register frame structure.
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: dump the correct %gs into a.out core dump
aout_dump_thread() read %gs but didn't include it in core dump. Fix
it.
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Commit 6194ba6ff6 ("x86: don't special-case
pmd allocations as much") made changes to the way we handle pmd allocations,
and while doing that it dropped a call to paravirt_release_pd on the
pgd page from the pgd_dtor code path.
As a result of this missing release, the hypervisor is now unaware of the
pgd page being freed, and as a result it ends up tracking this page as a
page table page.
After this the guest may start using the same page for other purposes, and
depending on what use the page is put to, it may result in various performance
and/or functional issues ( hangs, reboots).
Since this release is only required for VMI, I now release the pgd page from
the (vmi)_pgd_free hook.
Signed-off-by: Alok N Kataria <akataria@vmware.com>
Acked-by: Jeremy Fitzhardinge <jeremy@goop.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: <stable@kernel.org>
Impact: find right nr_irqs_gsi on some systems.
One test-system has gap between gsi's:
[ 0.000000] ACPI: IOAPIC (id[0x04] address[0xfec00000] gsi_base[0])
[ 0.000000] IOAPIC[0]: apic_id 4, version 0, address 0xfec00000, GSI 0-23
[ 0.000000] ACPI: IOAPIC (id[0x05] address[0xfeafd000] gsi_base[48])
[ 0.000000] IOAPIC[1]: apic_id 5, version 0, address 0xfeafd000, GSI 48-54
[ 0.000000] ACPI: IOAPIC (id[0x06] address[0xfeafc000] gsi_base[56])
[ 0.000000] IOAPIC[2]: apic_id 6, version 0, address 0xfeafc000, GSI 56-62
...
[ 0.000000] nr_irqs_gsi: 38
So nr_irqs_gsi is not right. some irq for MSI will overwrite with io_apic.
need to get that with acpi_probe_gsi when acpi io_apic is used
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
For Intel 7400 series CPUs, the recommendation is to use a clflush on the
monitored address just before monitor and mwait pair [1].
This clflush makes sure that there are no false wakeups from mwait when the
monitored address was recently written to.
[1] "MONITOR/MWAIT Recommendations for Intel Xeon Processor 7400 series"
section in specification update document of 7400 series
http://download.intel.com/design/xeon/specupdt/32033601.pdf
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
One of my past fixes to this code introduced a different new bug.
When using 32-bit "int $0x80" entry for a bogus syscall number,
the return value is not correctly set to -ENOSYS. This only happens
when neither syscall-audit nor syscall tracing is enabled (i.e., never
seen if auditd ever started). Test program:
/* gcc -o int80-badsys -m32 -g int80-badsys.c
Run on x86-64 kernel.
Note to reproduce the bug you need auditd never to have started. */
#include <errno.h>
#include <stdio.h>
int
main (void)
{
long res;
asm ("int $0x80" : "=a" (res) : "0" (99999));
printf ("bad syscall returns %ld\n", res);
return res != -ENOSYS;
}
The fix makes the int $0x80 path match the sysenter and syscall paths.
Reported-by: Dmitry V. Levin <ldv@altlinux.org>
Signed-off-by: Roland McGrath <roland@redhat.com>
Implement Linus's suggestion: introduce the hpet_cnt_ahead()
helper function to compare hpet time values - like other
wrapping counter comparisons are abstracted away elsewhere.
(jiffies, ktime_t, etc.)
Reported-by: Kirill Korotaev <dev@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Prevent kprobes from catching spurious faults which will cause infinite
recursive page-fault and memory corruption by stack overflow.
Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: <stable@kernel.org> [2.6.28.x]
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
At this time, the PowerNow! driver for K8 uses an experimentally
derived formula to calculate transition latency. The value it
provides is orders of magnitude too large on modern systems.
This patch replaces the formula with ACPI _PSS latency values
for more accuracy and better performance.
I've tested it on two 2nd generation Opteron systems, a 3rd
generation Operton system, and a Turion X2 without seeing any
stability problems.
Signed-off-by: Mark Langsdorf <mark.langsdorf@amd.com>
Signed-off-by: Thomas Renninger <trenn@suse.de>
Signed-off-by: Dave Jones <davej@redhat.com>
On an x86 system which doesn't support global mappings,
__supported_pte_mask has _PAGE_GLOBAL clear, to make sure it never
appears in the PTE. pfn_pte() and so on will enforce it with:
static inline pte_t pfn_pte(unsigned long page_nr, pgprot_t pgprot)
{
return __pte((((phys_addr_t)page_nr << PAGE_SHIFT) |
pgprot_val(pgprot)) & __supported_pte_mask);
}
However, we overload _PAGE_GLOBAL with _PAGE_PROTNONE on non-present
ptes to distinguish them from swap entries. However, applying
__supported_pte_mask indiscriminately will clear the bit and corrupt the
pte.
I guess the best fix is to only apply __supported_pte_mask to present
ptes. This seems like the right solution to me, as it means we can
completely ignore the issue of overlaps between the present pte bits and
the non-present pte-as-swap entry use of the bits.
__supported_pte_mask contains the set of flags we support on the
current hardware. We also use bits in the pte for things like
logically present ptes with no permissions, and swap entries for
swapped out pages. We should only apply __supported_pte_mask to
present ptes, because otherwise we may destroy other information being
stored in the ptes.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
There's a small problem with hpet_rtc_reinit function - it checks
for the:
hpet_readl(HPET_COUNTER) - hpet_t1_cmp > 0
to continue increasing both the HPET_T1_CMP (register) and the
hpet_t1_cmp (variable).
But since the HPET_COUNTER is always 32-bit, if the hpet_t1_cmp
is 64-bit this condition will always be FALSE once the latter hits
the 32-bit boundary, and we can have a situation, when we don't
increase the HPET_T1_CMP register high enough.
The result - timer stops ticking, since HPET_T1_CMP becomes less,
than the COUNTER and never increased again.
The solution is (based on Linus's suggestion) to not compare 64-bits
(on 64-bit x86), but to do the comparison on 32-bit signed
integers.
Reported-by: Kirill Korotaev <dev@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: cleanup
Some lines exceed the 80 char width making them unreadable.
Signed-off-by: Borislav Petkov <petkovbb@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This patch echoes what we already do on 32-bit since
90f7d25c6b, and prints the DMI
product name in show_regs, so that system specific problems can be
easily identified.
Signed-off-by: Kyle McMartin <kyle@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Patrick Ohly
Linus Torvalds
Steven Rostedt
Clemens Ladisch
Tejun Heo
Kyle McMartin
Alok Kataria
Yinghai Lu
Pallipadi, Venkatesh
Len Brown
Roland McGrath
Pavel Emelyanov
Masami Hiramatsu
Mark Langsdorf
Jeremy Fitzhardinge
Alex Chiang
Borislav Petkov
Kyle McMartin