commit: 8b7b80b9eb
[24/29] powerpc: Uprobes port to powerpc
Caused a clash with the fore200e driver:
In file included from drivers/atm/fore200e.c:70:0:
drivers/atm/fore200e.h:263:3: error: redefinition of typedef 'opcode_t' with different type
arch/powerpc/include/asm/probes.h:25:13: note: previous declaration of 'opcode_t' was here
Fix the namespace clash by making opcode_t in probes.h to ppc_opcode_t.
Signed-off-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Critical exception on 64-bit booke uses user-visible SPRG3 as scratch.
Restore VDSO information in SPRG3 on exception prolog.
Use a common sprg3 field in PACA for all powerpc64 architectures.
Signed-off-by: Mihai Caraman <mihai.caraman@freescale.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
patch_instruction() can be called very early on ppc32, when the kernel
isn't yet running at it's linked address. That can cause the !
is_kernel_addr() test in __put_user() to trip and call might_sleep()
which is very bad at that point during boot.
Use a lower level function instead for now, at least until we get to
rework ppc32 boot process to do the code patching later, like ppc64
does.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
We have been observing hangs, both of KVM guest vcpu tasks and more
generally, where a process that is woken doesn't properly wake up and
continue to run, but instead sticks in TASK_WAKING state. This
happens because the update of rq->wake_list in ttwu_queue_remote()
is not ordered with the update of ipi_message in
smp_muxed_ipi_message_pass(), and the reading of rq->wake_list in
scheduler_ipi() is not ordered with the reading of ipi_message in
smp_ipi_demux(). Thus it is possible for the IPI receiver not to see
the updated rq->wake_list and therefore conclude that there is nothing
for it to do.
In order to make sure that anything done before smp_send_reschedule()
is ordered before anything done in the resulting call to scheduler_ipi(),
this adds barriers in smp_muxed_message_pass() and smp_ipi_demux().
The barrier in smp_muxed_message_pass() is a full barrier to ensure that
there is a full ordering between the smp_send_reschedule() caller and
scheduler_ipi(). In smp_ipi_demux(), we use xchg() rather than
xchg_local() because xchg() includes release and acquire barriers.
Using xchg() rather than xchg_local() makes sense given that
ipi_message is not just accessed locally.
This moves the barrier between setting the message and calling the
cause_ipi() function into the individual cause_ipi implementations.
Most of them -- those that used outb, out_8 or similar -- already had
a full barrier because out_8 etc. include a sync before the MMIO
store. This adds an explicit barrier in the two remaining cases.
These changes made no measurable difference to the speed of IPIs as
measured using a simple ping-pong latency test across two CPUs on
different cores of a POWER7 machine.
The analysis of the reason why processes were not waking up properly
is due to Milton Miller.
Cc: stable@vger.kernel.org # v3.0+
Reported-by: Milton Miller <miltonm@bga.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
During a context switch we always restore the per thread DSCR value.
If we aren't doing explicit DSCR management
(ie thread.dscr_inherit == 0) and the default DSCR changed while
the process has been sleeping we end up with the wrong value.
Check thread.dscr_inherit and select the default DSCR or per thread
DSCR as required.
This was found with the following test case, when running with
more threads than CPUs (ie forcing context switching):
http://ozlabs.org/~anton/junkcode/dscr_default_test.c
With the four patches applied I can run a combination of all
test cases successfully at the same time:
http://ozlabs.org/~anton/junkcode/dscr_default_test.chttp://ozlabs.org/~anton/junkcode/dscr_explicit_test.chttp://ozlabs.org/~anton/junkcode/dscr_inherit_test.c
Signed-off-by: Anton Blanchard <anton@samba.org>
Cc: <stable@kernel.org> # 3.0+
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
If the default DSCR is non zero we set thread.dscr_inherit in
copy_thread() meaning the new thread and all its children will ignore
future updates to the default DSCR. This is not intended and is
a change in behaviour that a number of our users have hit.
We just need to inherit thread.dscr and thread.dscr_inherit from
the parent which ends up being much simpler.
This was found with the following test case:
http://ozlabs.org/~anton/junkcode/dscr_default_test.c
Signed-off-by: Anton Blanchard <anton@samba.org>
Cc: <stable@kernel.org> # 3.0+
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
When we update the DSCR either via emulation of mtspr(DSCR) or via
a change to dscr_default in sysfs we don't update thread.dscr.
We will eventually update it at context switch time but there is
a period where thread.dscr is incorrect.
If we fork at this point we will copy the old value of thread.dscr
into the child. To avoid this, always keep thread.dscr in sync with
reality.
This issue was found with the following testcase:
http://ozlabs.org/~anton/junkcode/dscr_inherit_test.c
Signed-off-by: Anton Blanchard <anton@samba.org>
Cc: <stable@kernel.org> # 3.0+
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Writing to dscr_default in sysfs doesn't actually change the DSCR -
we rely on a context switch on each CPU to do the work. There is no
guarantee we will get a context switch in a reasonable amount of time
so fire off an IPI to force an immediate change.
This issue was found with the following test case:
http://ozlabs.org/~anton/junkcode/dscr_explicit_test.c
Signed-off-by: Anton Blanchard <anton@samba.org>
Cc: <stable@kernel.org> # 3.0+
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
The CPU hotplug code for the powernv platform currently only puts
offline CPUs into nap mode if the powersave_nap variable is set.
However, HV-style KVM on this platform requires secondary CPU threads
to be offline and in nap mode. Since we know nap mode works just
fine on all POWER7 machines, and the only machines that support the
powernv platform are POWER7 machines, this changes the code to
always put offline CPUs into nap mode, regardless of powersave_nap.
Powersave_nap still controls whether or not CPUs go into nap mode
when idle, as before.
Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
At the moment the handler for hypervisor decrementer interrupts is
the same as for decrementer interrupts, i.e. timer_interrupt().
This is bogus; if we ever do get a hypervisor decrementer interrupt
it won't have anything to do with the next timer event. In fact
the only time we get hypervisor decrementer interrupts is when one
is left pending on exit from a KVM guest.
When we get a hypervisor decrementer interrupt we don't need to do
anything special to clear it, since they are edge-triggered on the
transition of HDEC from 0 to -1. Thus this adds an empty handler
function for them. We don't need to have them masked when interrupts
are soft-disabled, so we use STD_EXCEPTION_HV instead of
MASKABLE_EXCEPTION_HV.
Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
arch_update_cpu_topology() should only return 1 when the topology has
actually changed, and should return 0 otherwise.
This patch fixes a potential bug where rebuild_sched_domains() would
reinitialize the sched domains even when the topology hasn't changed.
Signed-off-by: Jesse Larrew <jlarrew@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Embedded.Hypervisor category defines GSPRG0..3 physical registers for guests.
Avoid SPRG4-7 usage as scratch in host exception handlers, otherwise guest
SPRG4-7 registers will be clobbered.
For bolted TLB miss exception handlers, which is the version currently
supported by KVM, use SPRN_SPRG_GEN_SCRATCH aka SPRG0 instead of
SPRN_SPRG_TLB_SCRATCH aka SPRG6. Keep using TLB PACA slots to fit in one
64-byte cache line.
For critical exception handlers use SPRG3 instead of SPRG7. Provide a routine
to store and restore user-visible SPRGs. This will be subsequently used
to restore VDSO information in SPRG3. Add EX_R13 to paca slots to free up
SPRG3 and change the critical exception epilog to use it.
Signed-off-by: Mihai Caraman <mihai.caraman@freescale.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Refactor exception prolog to get rid of mfspr srr1 duplicate. This was
introduced by KVM integration, with DO_KVM macro logic expecting srr1 value
earlier in r11.
Reserve r11 to hold srr1's value also required at the end of the prolog and
free up r10 to serve as spare in addition macros.
For syscalls case this change does not add any performance penalty. For irq
soft-disabled case the change adds a store/load of conditional register value
to/from a paca slot. Paca slots fit in one 64-byte cache line so these
additional operations have little impact on performance.
Signed-off-by: Mihai Caraman <mihai.caraman@freescale.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Hook DO_KVM macro into 64-bit booke for KVM integration. Extend interrupt
handlers' parameter list with interrupt vector numbers to accomodate the macro.
Only the bolted version of tlb miss handers is addressed now.
Signed-off-by: Mihai Caraman <mihai.caraman@freescale.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Guest Doorbell interrupts use guest save and restore registers. Add a new
Guest Doorbell exception type to accommodate GSRR0/1 SPRs usage in exception
prolog and fix the exception handler.
Signed-off-by: Mihai Caraman <mihai.caraman@freescale.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Machine check exception handler was using a wrong prolog. Hypervisors like
KVM which are called early from the exception handler rely on the interrupt
source.
Signed-off-by: Mihai Caraman <mihai.caraman@freescale.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This is the port of uprobes to powerpc. Usage is similar to x86.
[root@xxxx ~]# ./bin/perf probe -x /lib64/libc.so.6 malloc
Added new event:
probe_libc:malloc (on 0xb4860)
You can now use it in all perf tools, such as:
perf record -e probe_libc:malloc -aR sleep 1
[root@xxxx ~]# ./bin/perf record -e probe_libc:malloc -aR sleep 20
[ perf record: Woken up 22 times to write data ]
[ perf record: Captured and wrote 5.843 MB perf.data (~255302 samples) ]
[root@xxxx ~]# ./bin/perf report --stdio
...
69.05% tar libc-2.12.so [.] malloc
28.57% rm libc-2.12.so [.] malloc
1.32% avahi-daemon libc-2.12.so [.] malloc
0.58% bash libc-2.12.so [.] malloc
0.28% sshd libc-2.12.so [.] malloc
0.08% irqbalance libc-2.12.so [.] malloc
0.05% bzip2 libc-2.12.so [.] malloc
0.04% sleep libc-2.12.so [.] malloc
0.03% multipathd libc-2.12.so [.] malloc
0.01% sendmail libc-2.12.so [.] malloc
0.01% automount libc-2.12.so [.] malloc
The trap_nr addition patch is a prereq.
Signed-off-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Add thread_struct.trap_nr and use it to store the last exception
the thread experienced. In this patch, we populate the field at
various places where we force_sig_info() to the process.
This is also used in uprobes to determine if the probed instruction
caused an exception.
Signed-off-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Move is_trap() and relatives to a common file to be shared between kprobes
and uprobes.
Code movement only; no change in functionality.
Suggested by Michael Ellerman.
Signed-off-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
We have an old FIXME in reg.h which points out that we should standardise
on PVR_foo for our PVR #defines. Currently we use PVR_ on 32-bit and PV_
on 64-bit.
So do that rename and remove the FIXME.
Seeing as we're touching all but one usage of __is_processor(), rename it
to something less ugly and more indicative of what it does, which is
simply to check the PVR version.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
The pseries hvterm driver only registers a udbg backend (for xmon and
other low level debugging mechanisms) when hvc0 is recognized as the
firmware console at boot time, not if it's detected later on, for
example because the firmware is using a graphics card.
This can make debugging challenging especially under X11, and there's
really no good reason for that limitation, so let's hookup udbg
whenever hvc0 is detected instead.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
hvc_console has two methods to instanciate the consoles.
hvc_instanciate is meant to be called at early boot, while hvc_alloc is
called for more dynamically probed objects.
Currently, it only deals with adding kernel consoles in the former case,
which means for example that if a console only uses dynamic probing, it
will never be usable as a kernel console even when specifying
console=hvc0 explicitly, which could be considered annoying...
More specifically, on pseries, we only do the early instanciate for the
console currently used by the firmware, so if you have your firmware
configured to go to a video card, for example, you cannot get your
kernel console, oops messages, etc... on your serial port or hypervisor
console, which would be handy to deal with oopses.
This fixes it by checking if hvc_console.flags & CON_ENABLED is set when
registering a new dynamic console, and if not, redo the index check and
re-register the console if the index matches, allowing console=hvcN to
work.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
It contains no code and is not included by anyone.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
It's empty now, apart from other includes.
Fixup a few files that were getting things via this header.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
virt_to_abs() is just a wrapper around __pa(), call __pa() directly.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
These days they are just __va() and __pa() respectively.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
These days they are just __va() and __pa() respectively.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
These days they are just __va() and __pa() respectively.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
abs_to_virt() simply calls __va() and we'd like to get rid of it,
so replace all abs_to_virt() uses with __va().
Similarly virt_to_abs() just calls __pa().
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
abs_to_virt() is just a wrapper around __va(), call __va() directly.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
abs_to_virt() simply calls __va() and we'd like to get rid of it,
so replace all abs_to_virt() uses with __va().
__va() returns void *, so when assigning to a pointer there's no need
to cast.
Similarly virt_to_abs() just calls __pa().
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
These days they are just wrappers around __pa() and __va() respectively.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
These days they are just wrappers around __pa() and __va() respectively.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
abs_to_virt() is just a wrapper around __va(), call __va() directly.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Since commit f5339277 phys_to_abs() is 100% a nop, so just remove it.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
phys_to_abs() is a nop, don't use it.
virt_to_abs() is just a wrapper around __pa(), call __pa() directly.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
In commit f5339277 "powerpc: Remove FW_FEATURE ISERIES from arch code", we
removed the bulk of the iSeries code, but missed a few bits.
Remove the mschunks bits, these were only ever used on iSeries as far as I
know, and are definitely not used anymore.
Make it even clearer that phys_to_abs() is a nop, by making it a macro. We
still have a few users of this, but should clean those up.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Pull CIFS fixes from Steve French.
* 'for-next' of git://git.samba.org/sfrench/cifs-2.6:
CIFS: Fix cifs_do_create error hadnling
cifs: print error code if smb signature verification fails
CIFS: Fix log messages in packet checking for SMB2
CIFS: Protect i_nlink from being negative
Pull networking fixes from David Miller:
1) NLA_PUT* --> nla_put_* conversion got one case wrong in
nfnetlink_log, fix from Patrick McHardy.
2) Missed error return check in ipw2100 driver, from Julia Lawall.
3) PMTU updates in ipv4 were setting the expiry time incorrectly, fix
from Eric Dumazet.
4) SFC driver erroneously reversed src and dst when reporting filters
via ethtool.
5) Memory leak in CAN protocol and wrong setting of IRQF_SHARED in
sja1000 can platform driver, from Alexey Khoroshilov and Sven
Schmitt.
6) Fix multicast traffic scaling regression in ipv4_dst_destroy, only
take the lock when we really need to. From Eric Dumazet.
7) Fix non-root process spoofing in netlink, from Pablo Neira Ayuso.
8) CWND reduction in TCP is done incorrectly during non-SACK recovery,
fix from Yuchung Cheng.
9) Revert netpoll change, and fix what was actually a driver specific
problem. From Amerigo Wang. This should cure bootup hangs with
netconsole some people reported.
10) Fix xen-netfront invoking __skb_fill_page_desc() with a NULL page
pointer. From Ian Campbell.
11) SIP NAT fix for expectiontation creation, from Pablo Neira Ayuso.
12) __ip_rt_update_pmtu() needs RCU locking, from Eric Dumazet.
13) Fix usbnet deadlock on resume, can't use GFP_KERNEL in this
situation. From Oliver Neukum.
14) The davinci ethernet driver triggers an OOPS on removal because it
frees an MDIO object before unregistering it. Fix from Bin Liu.
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (41 commits)
net: qmi_wwan: add several new Gobi devices
fddi: 64 bit bug in smt_add_para()
net: ethernet: fix kernel OOPS when remove davinci_mdio module
net/xfrm/xfrm_state.c: fix error return code
net: ipv6: fix error return code
net: qmi_wwan: new device: Foxconn/Novatel E396
usbnet: fix deadlock in resume
cs89x0 : packet reception not working
netfilter: nf_conntrack: fix racy timer handling with reliable events
bnx2x: Correct the ndo_poll_controller call
bnx2x: Move netif_napi_add to the open call
ipv4: must use rcu protection while calling fib_lookup
bnx2x: fix 57840_MF pci id
net: ipv4: ipmr_expire_timer causes crash when removing net namespace
e1000e: DoS while TSO enabled caused by link partner with small MSS
l2tp: avoid to use synchronize_rcu in tunnel free function
gianfar: fix default tx vlan offload feature flag
netfilter: nf_nat_sip: fix incorrect handling of EBUSY for RTCP expectation
xen-netfront: use __pskb_pull_tail to ensure linear area is big enough on RX
netfilter: nfnetlink_log: fix error return code in init path
...
Gobi devices are composite, needing both the qcserial and
qmi_wwan drivers to support all functions. Re-syncing the
list of supported devices with qcserial.
Cc: Aleksander Morgado <aleksander@lanedo.com>
Cc: Thomas Tuttle <ttuttle@chromium.org>
Signed-off-by: Bjørn Mork <bjorn@mork.no>
Signed-off-by: David S. Miller <davem@tempietto.lan>
The intent was to set 4 bytes of data so that's why the sp_len is set
to 4 on the next line. The cast to u_long pointer clears 8 bytes
on 64 bit arches.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: David S. Miller <davem@tempietto.lan>
Andreas Bombe reported that the added ktime_t overflow checking added to
timespec_valid in commit 4e8b14526c ("time: Improve sanity checking of
timekeeping inputs") was causing problems with X.org because it caused
timeouts larger then KTIME_T to be invalid.
Previously, these large timeouts would be clamped to KTIME_MAX and would
never expire, which is valid.
This patch splits the ktime_t overflow checking into a new
timespec_valid_strict function, and converts the timekeeping codes
internal checking to use this more strict function.
Reported-and-tested-by: Andreas Bombe <aeb@debian.org>
Cc: Zhouping Liu <zliu@redhat.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Prarit Bhargava <prarit@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Signed-off-by: John Stultz <john.stultz@linaro.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This is a set of two bug fixes. One is the ATOMIC problem which is now
causing a compile failure in certain situations. The other is mishandling of
PER_LINUX32 which may also cause user visible effects.
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
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Merge tag 'parisc-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/parisc-2.6
Pull PARISC fixes from James Bottomley:
"This is a set of two bug fixes. One is the ATOMIC problem which is
now causing a compile failure in certain situations. The other is
mishandling of PER_LINUX32 which may also cause user visible effects.
Signed-off-by: James Bottomley <JBottomley@Parallels.com>"
* tag 'parisc-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/parisc-2.6:
[PARISC] fix personality flag check in copy_thread()
[PARISC] Redefine ATOMIC_INIT and ATOMIC64_INIT to drop the casts
Pull s390 fixes from Martin Schwidefsky:
"A couple of s390 bug fixes for 3.5-rc4"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
s390/32: Don't clobber personality flags on exec
s390/smp: add missing smp_store_status() for !SMP
s390/dasd: fix ioctl return value
s390: Always use "long" for ssize_t to match size_t
