Signed-off-by: Andres Salomon <dilinger@queued.net>
Cc: H. Peter Anvin <hpa@linux.intel.com>
LKML-Reference: <20100618174653.7755a39a@dev.queued.net>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Add support for saving OFW's cif, and later calling into it to run OFW
commands. OFW remains resident in memory, living within virtual range
0xff800000 - 0xffc00000. A single page directory entry points to the
pgdir that OFW actually uses, so rather than saving the entire page
table, we grab and install that one entry permanently in the kernel's
page table.
This is currently only used by the OLPC XO. Note that this particular
calling convention breaks PAE and PAT, and so cannot be used on newer
x86 hardware.
Signed-off-by: Andres Salomon <dilinger@queued.net>
LKML-Reference: <20100618174653.7755a39a@dev.queued.net>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
* 'linux_next' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/i7core: (83 commits)
i7core_edac: Better describe the supported devices
Add support for Westmere to i7core_edac driver
i7core_edac: don't free on success
i7core_edac: Add support for X5670
Always call i7core_[ur]dimm_check_mc_ecc_err
i7core_edac: fix memory leak of i7core_dev
EDAC: add __init to i7core_xeon_pci_fixup
i7core_edac: Fix wrong device id for channel 1 devices
i7core: add support for Lynnfield alternate address
i7core_edac: Add initial support for Lynnfield
i7core_edac: do not export static functions
edac: fix i7core build
edac: i7core_edac produces undefined behaviour on 32bit
i7core_edac: Use a more generic approach for probing PCI devices
i7core_edac: PCI device is called NONCORE, instead of NOCORE
i7core_edac: Fix ringbuffer maxsize
i7core_edac: First store, then increment
i7core_edac: Better parse "any" addrmask
i7core_edac: Use a lockless ringbuffer
edac: Create an unique instance for each kobj
...
* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
x86, smpboot: Fix cores per node printing on boot
x86/amd-iommu: Fall back to GART if initialization fails
x86/amd-iommu: Fix crash when request_mem_region fails
x86/mm: Remove unused DBG() macro
arch/x86/kernel: Add missing spin_unlock
* 'perf-fixes-for-linus-2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
perf: Fix crash in swevents
perf buildid-list: Fix --with-hits event processing
perf scripts python: Give field dict to unhandled callback
perf hist: fix objdump output parsing
perf-record: Check correct pid when forking
perf: Do the comm inheritance per thread in event__process_task
perf: Use event__process_task from perf sched
perf: Process comm events by tid
blktrace: Fix new kernel-doc warnings
perf_events: Fix unincremented buffer base on partial copy
perf_events: Fix event scheduling issues introduced by transactional API
perf_events, trace: Fix perf_trace_destroy(), mutex went missing
perf_events, trace: Fix probe unregister race
perf_events: Fix races in group composition
perf_events: Fix races and clean up perf_event and perf_mmap_data interaction
Percpu initialization happens now after booting the cores on the
machine and this causes them all to be displayed as belonging to
node 0:
Jun 8 05:57:21 kepek kernel: [ 0.106999] Booting Node 0,
Processors #1#2#3#4#5#6#7#8#9#10#11#12#13#14#15#16#17#18#19#20#21#22#23 Ok.
Use early_cpu_to_node() to get the correct node of each core
instead.
Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>
Cc: Mike Travis <travis@sgi.com>
LKML-Reference: <20100601190455.GA14237@aftab>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
* 'for-35' of git://repo.or.cz/linux-kbuild: (81 commits)
kbuild: Revert part of e8d400a to resolve a conflict
kbuild: Fix checking of scm-identifier variable
gconfig: add support to show hidden options that have prompts
menuconfig: add support to show hidden options which have prompts
gconfig: remove show_debug option
gconfig: remove dbg_print_ptype() and dbg_print_stype()
kconfig: fix zconfdump()
kconfig: some small fixes
add random binaries to .gitignore
kbuild: Include gen_initramfs_list.sh and the file list in the .d file
kconfig: recalc symbol value before showing search results
.gitignore: ignore *.lzo files
headerdep: perlcritic warning
scripts/Makefile.lib: Align the output of LZO
kbuild: Generate modules.builtin in make modules_install
Revert "kbuild: specify absolute paths for cscope"
kbuild: Do not unnecessarily regenerate modules.builtin
headers_install: use local file handles
headers_check: fix perl warnings
export_report: fix perl warnings
...
This patch implements a fallback to the GART IOMMU if this
is possible and the AMD IOMMU initialization failed.
Otherwise the fallback would be nommu which is very
problematic on machines with more than 4GB of memory or
swiotlb which hurts io-performance.
Cc: stable@kernel.org
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
When request_mem_region fails the error path tries to
disable the IOMMUs. This accesses the mmio-region which was
not allocated leading to a kernel crash. This patch fixes
the issue.
Cc: stable@kernel.org
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
The transactional API patch between the generic and model-specific
code introduced several important bugs with event scheduling, at
least on X86. If you had pinned events, e.g., watchdog, and were
over-committing the PMU, you would get bogus counts. The bug was
showing up on Intel CPU because events would move around more
often that on AMD. But the problem also existed on AMD, though
harder to expose.
The issues were:
- group_sched_in() was missing a cancel_txn() in the error path
- cpuc->n_added was not properly maintained, leading to missing
actions in hw_perf_enable(), i.e., n_running being 0. You cannot
update n_added until you know the transaction has succeeded. In
case of failed transaction n_added was not adjusted back.
- in case of failed transactions, event_sched_out() was called
and eventually invoked x86_disable_event() to touch the HW reg.
But with transactions, on X86, event_sched_in() does not touch
HW registers, it simply collects events into a list. Thus, you
could end up calling x86_disable_event() on a counter which
did not correspond to the current event when idx != -1.
The patch modifies the generic and X86 code to avoid all those problems.
First, we keep track of the number of events added last. In case the
transaction fails, we substract them from n_added. This approach is
necessary (as opposed to delaying updates to n_added) because not all
event updates use the transaction API, e.g., single events.
Second, we encapsulate the event_sched_in() and event_sched_out() in
group_sched_in() inside the transaction. That makes the operations
symmetrical and you can also detect that you are inside a transaction
and skip the HW reg access by checking cpuc->group_flag.
With this patch, you can now overcommit the PMU even with pinned
system-wide events present and still get valid counts.
Signed-off-by: Stephane Eranian <eranian@google.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1274796225.5882.1389.camel@twins>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
x86, cpufeature: Unbreak compile with gcc 3.x
x86, pat: Fix memory leak in free_memtype
x86, k8: Fix section mismatch for powernowk8_exit()
lib/atomic64_test: fix missing include of linux/kernel.h
x86: remove last traces of quicklist usage
x86, setup: Phoenix BIOS fixup is needed on Dell Inspiron Mini 1012
x86: "nosmp" command line option should force the system into UP mode
arch/x86/pci: use kasprintf
x86, apic: ack all pending irqs when crashed/on kexec
* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (61 commits)
tracing: Add __used annotation to event variable
perf, trace: Fix !x86 build bug
perf report: Support multiple events on the TUI
perf annotate: Fix up usage of the build id cache
x86/mmiotrace: Remove redundant instruction prefix checks
perf annotate: Add TUI interface
perf tui: Remove annotate from popup menu after failure
perf report: Don't start the TUI if -D is used
perf: Fix getline undeclared
perf: Optimize perf_tp_event_match()
perf: Remove more code from the fastpath
perf: Optimize the !vmalloc backed buffer
perf: Optimize perf_output_copy()
perf: Fix wakeup storm for RO mmap()s
perf-record: Share per-cpu buffers
perf-record: Remove -M
perf: Ensure that IOC_OUTPUT isn't used to create multi-writer buffers
perf, trace: Optimize tracepoints by using per-tracepoint-per-cpu hlist to track events
perf, trace: Optimize tracepoints by removing IRQ-disable from perf/tracepoint interaction
perf tui: Allow disabling the TUI on a per command basis in ~/.perfconfig
...
x86 arch specific changes to use generic numa_node_id() based on generic
percpu variable infrastructure. Back out x86's custom version of
numa_node_id()
Signed-off-by: Lee Schermerhorn <lee.schermerhorn@hp.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: Nick Piggin <npiggin@suse.de>
Cc: David Rientjes <rientjes@google.com>
Cc: Eric Whitney <eric.whitney@hp.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: <linux-arch@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
sync_single_range_for_cpu and sync_single_range_for_device hooks in
swiotlb_dma_ops are unnecessary because sync_single_for_cpu and
sync_single_for_device are used there.
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
By the previous modification, the cpu notifier can return encapsulate
errno value. This converts the cpu notifiers for msr, cpuid, and
therm_throt.
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add a spin_unlock missing on the error path. The locks and unlocks are
balanced in other functions, so it seems that the same should be the case
here.
The semantic match that finds this problem is as follows:
(http://coccinelle.lip6.fr/)
// <smpl>
@@
expression E1;
@@
* spin_lock(E1,...);
<+... when != E1
if (...) {
... when != E1
* return ...;
}
...+>
* spin_unlock(E1,...);
// </smpl>
Cc: stable@kernel.org
Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Fix the following warning:
"WARNING: arch/x86/kernel/built-in.o(.exit.text+0x72):
Section mismatch in reference from the function powernowk8_exit() to the variable .cpuinit.data:cpb_nb
The function __exit powernowk8_exit() references a variable
__cpuinitdata cpb_nb. This is often seen when error handling in the exit
function uses functionality in the init path. The fix is often to remove
the __cpuinitdata annotation of cpb_nb so it may be used outside an init
section."
Cc: <stable@kernel.org>
Reported-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>
LKML-Reference: <20100525152858.GA24836@aftab>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
This adds:
alias: devname:<name>
to some common kernel modules, which will allow the on-demand loading
of the kernel module when the device node is accessed.
Ideally all these modules would be compiled-in, but distros seems too
much in love with their modularization that we need to cover the common
cases with this new facility. It will allow us to remove a bunch of pretty
useless init scripts and modprobes from init scripts.
The static device node aliases will be carried in the module itself. The
program depmod will extract this information to a file in the module directory:
$ cat /lib/modules/2.6.34-00650-g537b60d-dirty/modules.devname
# Device nodes to trigger on-demand module loading.
microcode cpu/microcode c10:184
fuse fuse c10:229
ppp_generic ppp c108:0
tun net/tun c10:200
dm_mod mapper/control c10:235
Udev will pick up the depmod created file on startup and create all the
static device nodes which the kernel modules specify, so that these modules
get automatically loaded when the device node is accessed:
$ /sbin/udevd --debug
...
static_dev_create_from_modules: mknod '/dev/cpu/microcode' c10:184
static_dev_create_from_modules: mknod '/dev/fuse' c10:229
static_dev_create_from_modules: mknod '/dev/ppp' c108:0
static_dev_create_from_modules: mknod '/dev/net/tun' c10:200
static_dev_create_from_modules: mknod '/dev/mapper/control' c10:235
udev_rules_apply_static_dev_perms: chmod '/dev/net/tun' 0666
udev_rules_apply_static_dev_perms: chmod '/dev/fuse' 0666
A few device nodes are switched to statically allocated numbers, to allow
the static nodes to work. This might also useful for systems which still run
a plain static /dev, which is completely unsafe to use with any dynamic minor
numbers.
Note:
The devname aliases must be limited to the *common* and *single*instance*
device nodes, like the misc devices, and never be used for conceptually limited
systems like the loop devices, which should rather get fixed properly and get a
control node for losetup to talk to, instead of creating a random number of
device nodes in advance, regardless if they are ever used.
This facility is to hide the mess distros are creating with too modualized
kernels, and just to hide that these modules are not compiled-in, and not to
paper-over broken concepts. Thanks! :)
Cc: Greg Kroah-Hartman <gregkh@suse.de>
Cc: David S. Miller <davem@davemloft.net>
Cc: Miklos Szeredi <miklos@szeredi.hu>
Cc: Chris Mason <chris.mason@oracle.com>
Cc: Alasdair G Kergon <agk@redhat.com>
Cc: Tigran Aivazian <tigran@aivazian.fsnet.co.uk>
Cc: Ian Kent <raven@themaw.net>
Signed-Off-By: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Patch b7e2ecef92 (perf, trace: Optimize tracepoints by removing
IRQ-disable from perf/tracepoint interaction) made the
unfortunate mistake of assuming the world is x86 only, correct
this.
The problem was that perf_fetch_caller_regs() did
local_save_flags() into regs->flags, and I re-used that to
remove another local_save_flags(), forgetting !x86 doesn't have
regs->flags.
Do the reverse, remove the local_save_flags() from
perf_fetch_caller_regs() and let the ftrace site do the
local_save_flags() instead.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Paul Mackerras <paulus@samba.org>
Cc: acme@redhat.com
Cc: efault@gmx.de
Cc: fweisbec@gmail.com
Cc: rostedt@goodmis.org
LKML-Reference: <1274778175.5882.623.camel@twins>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
The low-memory corruption checker triggers during suspend/resume, so we
need to reserve the low 64k. Don't be fooled that the BIOS identifies
itself as "Dell Inc.", it's still Phoenix BIOS.
[ hpa: I think we blacklist almost every BIOS in existence. We should
either change this to a whitelist or just make it unconditional. ]
Signed-off-by: Gabor Gombas <gombasg@digikabel.hu>
LKML-Reference: <201005241913.o4OJDIMM010877@imap1.linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Cc: <stable@kernel.org>
Bits set in cpu_possible_mask prior to the execution of
prefill_possible_map() (i.e. when parsing ACPI or MPS tables) would
prevent the SMP alternatives logic from switching to UP mode, plus
unnecessary setup of per-CPU data for CPUs that can never come online.
Additionally, without CONFIG_HOTPLUG_CPU disabled CPUs can never come
online, and hence setting cpu_possible_mask bits for them is again a
simple waste of resources.
Signed-off-by: Jan Beulich <jbeulich@novell.com>
LKML-Reference: <201005241913.o4OJDH3Z010874@imap1.linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
When the SMP kernel decides to crash_kexec() the local APICs may have
pending interrupts in their vector tables.
The setup routine for the local APIC has a deficient mechanism for
clearing these interrupts, it only handles interrupts that has already
been dispatched to the local core for servicing (the ISR register) safely,
it doesn't consider lower prioritized queued interrupts stored in the IRR
register.
If you have more than one pending interrupt within the same 32 bit word in
the LAPIC vector table registers you may find yourself entering the IO
APIC setup with pending interrupts left in the LAPIC. This is a situation
for wich the IO APIC setup is not prepared. Depending of what/which
interrupt vector/vectors are stuck in the APIC tables your system may show
various degrees of malfunctioning. That was the reason why the
check_timer() failed in our system, the timer interrupts was blocked by
pending interrupts from the old kernel when routed trough the IO APIC.
Additional comment from Jiri Bohac:
==============
If this should go into stable release,
I'd add some kind of limit on the number of iterations, just to be safe from
hard to debug lock-ups:
+if (loops++ > MAX_LOOPS) {
+ printk("LAPIC pending clean-up")
+ break;
+}
while (queued);
with MAX_LOOPS something like 1E9 this would leave plenty of time for the
pending IRQs to be cleared and would and still cause at most a second of delay
if the loop were to lock-up for whatever reason.
[trenn@suse.de:
V2: Use tsc if avail to bail out after 1 sec due to possible virtual
apic_read calls which may take rather long (suggested by: Avi Kivity
<avi@redhat.com>) If no tsc is available bail out quickly after
cpu_khz, if we broke out too early and still have irqs pending (which
should never happen?) we still get a WARN_ON...
V3: - Fixed indentation -> checkpatch clean
- max_loops must be signed
V4: - Fix typo, mixed up tsc and ntsc in first rdtscll() call
V5: Adjust WARN_ON() condition to also catch error in cpu_has_tsc case]
Cc: <jbohac@novell.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Kerstin Jonsson <kerstin.jonsson@ericsson.com>
Cc: Avi Kivity <avi@redhat.com>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
Tested-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Thomas Renninger <trenn@suse.de>
LKML-Reference: <201005241913.o4OJDGWM010865@imap1.linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
* 'kvm-updates/2.6.35' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (269 commits)
KVM: x86: Add missing locking to arch specific vcpu ioctls
KVM: PPC: Add missing vcpu_load()/vcpu_put() in vcpu ioctls
KVM: MMU: Segregate shadow pages with different cr0.wp
KVM: x86: Check LMA bit before set_efer
KVM: Don't allow lmsw to clear cr0.pe
KVM: Add cpuid.txt file
KVM: x86: Tell the guest we'll warn it about tsc stability
x86, paravirt: don't compute pvclock adjustments if we trust the tsc
x86: KVM guest: Try using new kvm clock msrs
KVM: x86: export paravirtual cpuid flags in KVM_GET_SUPPORTED_CPUID
KVM: x86: add new KVMCLOCK cpuid feature
KVM: x86: change msr numbers for kvmclock
x86, paravirt: Add a global synchronization point for pvclock
x86, paravirt: Enable pvclock flags in vcpu_time_info structure
KVM: x86: Inject #GP with the right rip on efer writes
KVM: SVM: Don't allow nested guest to VMMCALL into host
KVM: x86: Fix exception reinjection forced to true
KVM: Fix wallclock version writing race
KVM: MMU: Don't read pdptrs with mmu spinlock held in mmu_alloc_roots
KVM: VMX: enable VMXON check with SMX enabled (Intel TXT)
...
Allow kdb to work properly with with earlyprintk=vga by interpreting
the backspace and carriage return output characters. These
interpretation of these characters is used for simple line editing
provided in the kdb shell.
CC: Thomas Gleixner <tglx@linutronix.de>
CC: Ingo Molnar <mingo@redhat.com>
CC: H. Peter Anvin <hpa@zytor.com>
CC: x86@kernel.org
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
If the kernel debugger was configured, attached and started with
kgdbwait, the hardware breakpoint registers should get restored by the
kgdb code which is managing the dr registers.
CC: x86@kernel.org
CC: Thomas Gleixner <tglx@linutronix.de>
CC: Ingo Molnar <mingo@redhat.com>
CC: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
It is not possible to use the hw_breakpoint.c API prior to mm_init(),
but it is possible to use hardware breakpoints with the kernel
debugger.
Prior to smp_init() it is possible to simply write to the dr registers
of the boot cpu directly. This can be used up until the
kgdb_arch_late() is invoked, at which point the standard hw_breakpoint.c
API will get used.
CC: Frederic Weisbecker <fweisbec@gmail.com>
CC: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
The kernel debugger can operate well before mm_init(), but the x86
hardware breakpoint code which uses the perf api requires that the
kernel allocators are initialized.
This means the kernel debug core needs to provide an optional arch
specific call back to allow the initialization functions to run after
the kernel has been further initialized.
The kdb shell already had a similar restriction with an early
initialization and late initialization. The kdb_init() was moved into
the debug core's version of the late init which is called
dbg_late_init();
CC: kgdb-bugreport@lists.sourceforge.net
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Allow the x86 arch to have early exception processing for the purpose
of debugging via the kgdb.
Signed-off-by: Jan Kiszka <jan.kiszka@web.de>
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
The only way the debugger can handle a trap in inside rcu_lock,
notify_die, or atomic_notifier_call_chain without a triple fault is
to have a low level "first opportunity handler" in the int3 exception
handler.
Generally this will be something the vast majority of folks will not
need, but for those who need it, it is added as a kernel .config
option called KGDB_LOW_LEVEL_TRAP.
CC: Ingo Molnar <mingo@elte.hu>
CC: Thomas Gleixner <tglx@linutronix.de>
CC: H. Peter Anvin <hpa@zytor.com>
CC: x86@kernel.org
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Remove all the references to the kgdb_post_primary_code. This
function serves no useful purpose because you can obtain the same
information from the "struct kgdb_state *ks" from with in the
debugger, if for some reason you want the data.
Also remove the unintentional duplicate assignment for ks->ex_vector.
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
These are the minimum changes to the kgdb core in order to enable an
API to connect a new front end (kdb) to the debug core.
This patch introduces the dbg_kdb_mode variable controls where the
user level I/O is routed. It will be routed to the gdbstub (kgdb) or
to the kdb front end which is a simple shell available over the kgdboc
connection.
You can switch back and forth between kdb or the gdb stub mode of
operation dynamically. From gdb stub mode you can blindly type
"$3#33", or from the kdb mode you can enter "kgdb" to switch to the
gdb stub.
The logic in the debug core depends on kdb to look for the typical gdb
connection sequences and return immediately with KGDB_PASS_EVENT if a
gdb serial command sequence is detected. That should allow a
reasonably seamless transition between kdb -> gdb without leaving the
kernel exception state. The two gdb serial queries that kdb is
responsible for detecting are the "?" and "qSupported" packets.
CC: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Acked-by: Martin Hicks <mort@sgi.com>
* 'acpica' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-acpi-2.6: (22 commits)
ACPI: fix early DSDT dmi check warnings on ia64
ACPICA: Update version to 20100428.
ACPICA: Update/clarify some parameter names associated with acpi_handle
ACPICA: Rename acpi_ex_system_do_suspend->acpi_ex_system_do_sleep
ACPICA: Prevent possible allocation overrun during object copy
ACPICA: Split large file, evgpeblk
ACPICA: Add GPE support for dynamically loaded ACPI tables
ACPICA: Clarify/rename some root table descriptor fields
ACPICA: Update version to 20100331.
ACPICA: Minimize the differences between linux GPE code and ACPICA code base
ACPI: add boot option acpi=copy_dsdt to fix corrupt DSDT
ACPICA: Update DSDT copy/detection.
ACPICA: Add subsystem option to force copy of DSDT to local memory
ACPICA: Add detection of corrupted/replaced DSDT
ACPICA: Add write support for DataTable operation regions
ACPICA: Fix for acpi_reallocate_root_table for incorrect root table copy
ACPICA: Update comments/headers, no functional change
ACPICA: Update version to 20100304
ACPICA: Fix for possible fault in acpi_ex_release_mutex
ACPICA: Standardize integer output for ACPICA warnings/errors
...
Traditionally, fatal MCE will cause Linux print error log to console
then reboot. Because MCE registers will preserve their content after
warm reboot, the hardware error can be logged to disk or network after
reboot. But system may fail to warm reboot, then you may lose the
hardware error log. ERST can help here. Through saving the hardware
error log into flash via ERST before go panic, the hardware error log
can be gotten from the flash after system boot successful again.
The fatal MCE processing procedure with ERST involved is as follow:
- Hardware detect error, MCE raised
- MCE read MCE registers, check error severity (fatal), prepare error record
- Write MCE error record into flash via ERST
- Go panic, then trigger system reboot
- System reboot, /sbin/mcelog run, it reads /dev/mcelog to check flash
for error record of previous boot via ERST, and output and clear
them if available
- /sbin/mcelog logs error records into disk or network
ERST only accepts CPER record format, but there is no pre-defined CPER
section can accommodate all information in struct mce, so a customized
section type is defined to hold struct mce inside a CPER record as an
error section.
Signed-off-by: Huang Ying <ying.huang@intel.com>
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
Generic Hardware Error Source provides a way to report platform
hardware errors (such as that from chipset). It works in so called
"Firmware First" mode, that is, hardware errors are reported to
firmware firstly, then reported to Linux by firmware. This way, some
non-standard hardware error registers or non-standard hardware link
can be checked by firmware to produce more valuable hardware error
information for Linux.
Now, only SCI notification type and memory errors are supported. More
notification type and hardware error type will be added later. These
memory errors are reported to user space through /dev/mcelog via
faking a corrected Machine Check, so that the error memory page can be
offlined by /sbin/mcelog if the error count for one page is beyond the
threshold.
On some machines, Machine Check can not report physical address for
some corrected memory errors, but GHES can do that. So this simplified
GHES is implemented firstly.
Signed-off-by: Huang Ying <ying.huang@intel.com>
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
* 'timers-for-linus-hpet' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
x86, hpet: Add reference to chipset erratum documentation for disable-hpet-msi-quirk
x86, hpet: Restrict read back to affected ATI chipsets
If the HV told us we can fully trust the TSC, skip any
correction
Signed-off-by: Glauber Costa <glommer@redhat.com>
Acked-by: Zachary Amsden <zamsden@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
We now added a new set of clock-related msrs in replacement of the old
ones. In theory, we could just try to use them and get a return value
indicating they do not exist, due to our use of kvm_write_msr_save.
However, kvm clock registration happens very early, and if we ever
try to write to a non-existant MSR, we raise a lethal #GP, since our
idt handlers are not in place yet.
So this patch tests for a cpuid feature exported by the host to
decide which set of msrs are supported.
Signed-off-by: Glauber Costa <glommer@redhat.com>
Acked-by: Zachary Amsden <zamsden@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
In recent stress tests, it was found that pvclock-based systems
could seriously warp in smp systems. Using ingo's time-warp-test.c,
I could trigger a scenario as bad as 1.5mi warps a minute in some systems.
(to be fair, it wasn't that bad in most of them). Investigating further, I
found out that such warps were caused by the very offset-based calculation
pvclock is based on.
This happens even on some machines that report constant_tsc in its tsc flags,
specially on multi-socket ones.
Two reads of the same kernel timestamp at approx the same time, will likely
have tsc timestamped in different occasions too. This means the delta we
calculate is unpredictable at best, and can probably be smaller in a cpu
that is legitimately reading clock in a forward ocasion.
Some adjustments on the host could make this window less likely to happen,
but still, it pretty much poses as an intrinsic problem of the mechanism.
A while ago, I though about using a shared variable anyway, to hold clock
last state, but gave up due to the high contention locking was likely
to introduce, possibly rendering the thing useless on big machines. I argue,
however, that locking is not necessary.
We do a read-and-return sequence in pvclock, and between read and return,
the global value can have changed. However, it can only have changed
by means of an addition of a positive value. So if we detected that our
clock timestamp is less than the current global, we know that we need to
return a higher one, even though it is not exactly the one we compared to.
OTOH, if we detect we're greater than the current time source, we atomically
replace the value with our new readings. This do causes contention on big
boxes (but big here means *BIG*), but it seems like a good trade off, since
it provide us with a time source guaranteed to be stable wrt time warps.
After this patch is applied, I don't see a single warp in time during 5 days
of execution, in any of the machines I saw them before.
Signed-off-by: Glauber Costa <glommer@redhat.com>
Acked-by: Zachary Amsden <zamsden@redhat.com>
CC: Jeremy Fitzhardinge <jeremy@goop.org>
CC: Avi Kivity <avi@redhat.com>
CC: Marcelo Tosatti <mtosatti@redhat.com>
CC: Zachary Amsden <zamsden@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
This patch removes one padding byte and transform it into a flags
field. New versions of guests using pvclock will query these flags
upon each read.
Flags, however, will only be interpreted when the guest decides to.
It uses the pvclock_valid_flags function to signal that a specific
set of flags should be taken into consideration. Which flags are valid
are usually devised via HV negotiation.
Signed-off-by: Glauber Costa <glommer@redhat.com>
CC: Jeremy Fitzhardinge <jeremy@goop.org>
Acked-by: Zachary Amsden <zamsden@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Per document, for feature control MSR:
Bit 1 enables VMXON in SMX operation. If the bit is clear, execution
of VMXON in SMX operation causes a general-protection exception.
Bit 2 enables VMXON outside SMX operation. If the bit is clear, execution
of VMXON outside SMX operation causes a general-protection exception.
This patch is to enable this kind of check with SMX for VMXON in KVM.
Signed-off-by: Shane Wang <shane.wang@intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
This snippet somehow escaped the commit:
| commit 137351e0fe
| Author: Cyrill Gorcunov <gorcunov@openvz.org>
| Date: Sat May 8 15:25:52 2010 +0400
|
| x86, perf: P4 PMU -- protect sensible procedures from preemption
so bring it eventually back. It helps to catch
preemption issue (if there will be, rule of thumb --
don't use raw_ if you can).
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Lin Ming <ming.m.lin@intel.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <20100518212439.167259349@openvz.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
To prevent from clashes in future code modifications
do a real check for ESCR address being in hash. At
moment the callers are known to pass sane values but
better to be on a safe side.
And comment fix.
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
CC: Lin Ming <ming.m.lin@intel.com>
CC: Peter Zijlstra <a.p.zijlstra@chello.nl>
CC: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <20100518212439.004503600@openvz.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
