There is a small race window in the __switch_to code in regard to
the transfer of the TIF_MCCK_PENDING bit from the previous to the
next task. The bit is transferred before the task struct pointer
and the thread-info pointer for the next task has been stored to
lowcore. If a machine check sets the TIF_MCCK_PENDING bit between
the transfer code and the store of current/thread_info the bit
is still set for the previous task. And if the previous task has
terminated it can get lost. The effect is that a pending CRW is
not retrieved until the next machine checks sets TIF_MCCK_PENDING.
To fix this reorder __switch_to to first store the task struct
and thread-info pointer and then do the transfer of the bit.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Use HAVE_MARCH_Z9_109_FEATURES to figure out if stckf is available
at compile time.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The store clock fast instruction saves a couple of instructions compared
to the store clock instruction. Always use stckf instead of stck if it
is available.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Reviewed-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Remove the builtin tape ipl code. If somebody really wants to create a
tape which can be ipl'ed from, then this can be achieved by using zipl.
zipl can write an ipl record to a tape device and aftwards the kernel
image must be written to tape.
The steps are described in the "Linux on System z - Device Drivers,
Features, and Commands" book (SC33-8411).
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The code in entry[64].S calls do_signal only on return to user space.
user_mode(regs) is true for every calls to do_signal, it is unnecessary
to recheck user_mode at the start of do_signal and the legacy signal
stack switching path in get_sigframe is never reached.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Replace the check for TIF_SIE in the fault handler by a check for PF_VCPU.
With the last user of TIF_SIE gone we can now remove the bit.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
HANDLE_SIE_INTERCEPT is called early, use supervisor state and
instruction address to decide if the reset of the PSW to sie_loop
is required.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
To allow correct stack backtraces the backchain for the external
interrupt handler is now initialized with zero like it is already
done for example by io_int_handler().
Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Add missing #ifdep CONFIG_HOTPLUG_CPU to get rid of this one:
arch/s390/kernel/smp.c:229:13: warning: 'pcpu_free_lowcore'
defined but not used [-Wunused-function]
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
- Store uids and gids with kuid_t and kgid_t in struct kstat
- Convert uid and gids to userspace usable values with
from_kuid and from_kgid
Acked-by: Serge Hallyn <serge.hallyn@canonical.com>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Same code. Use the generic version. The special Makefile treatment is
pointless anyway as init_task.o contains only data which is handled by
the linker script. So no point on being treated like head text.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Link: http://lkml.kernel.org/r/20120503085035.271439530@linutronix.de
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Merge tag 'v3.4-rc5' into next
Linux 3.4-rc5
Merge to pull in prerequisite change for Smack:
86812bb0de
Requested by Casey.
As a first step to converting struct cred to be all kuid_t and kgid_t
values convert the group values stored in group_info to always be
kgid_t values. Unless user namespaces are used this change should
have no effect.
Acked-by: Serge Hallyn <serge.hallyn@canonical.com>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Link: http://lkml.kernel.org/r/20120420124557.652574928@linutronix.de
Preparatory patch to make the idle thread allocation for secondary
cpus generic.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Mike Frysinger <vapier@gentoo.org>
Cc: Jesper Nilsson <jesper.nilsson@axis.com>
Cc: Richard Kuo <rkuo@codeaurora.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Hirokazu Takata <takata@linux-m32r.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: David Howells <dhowells@redhat.com>
Cc: James E.J. Bottomley <jejb@parisc-linux.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: David S. Miller <davem@davemloft.net>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: x86@kernel.org
Link: http://lkml.kernel.org/r/20120420124556.964170564@linutronix.de
This change is inspired by
https://lkml.org/lkml/2012/4/16/14
which fixes the build warnings for arches that don't support
CONFIG_HAVE_ARCH_SECCOMP_FILTER.
In particular, there is no requirement for the return value of
secure_computing() to be checked unless the architecture supports
seccomp filter. Instead of silencing the warnings with (void)
a new static inline is added to encode the expected behavior
in a compiler and human friendly way.
v2: - cleans things up with a static inline
- removes sfr's signed-off-by since it is a different approach
v1: - matches sfr's original change
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Will Drewry <wad@chromium.org>
Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: James Morris <james.l.morris@oracle.com>
The stfle() function writes into lowcore memory when stfl_fac_list
is initialized with "S390_lowcore.stfl_fac_list = 0". For older
compilers this triggers a lowcore exception. With newer compilers
and "-OXX" compile option the bug does not show up because
the "S390_lowcore.stfl_fac_list" initialization is removed by the
compiler. The reason for thatis the incorrect "=m"
(S390_lowcore.stfl_fac_list) constraint in the stfl inline assembly.
The following shows the disassembly of the stfle() optimized code
that is inlined in the lgr_info_get() function:
000000000011325c <lgr_info_get>:
11325c: eb 9f f0 60 00 24 stmg %r9,%r15,96(%r15)
113262: c0 d0 00 29 0e 47 larl %r13,634ef0 <servi..>
113268: a7 f1 3f c0 tml %r15,16320
11326c: b9 04 00 ef lgr %r14,%r15
113270: a7 84 00 01 je 113272 <lgr_info_g..>
113274: a7 fb ff c0 aghi %r15,-64
113278: b9 04 00 c2 lgr %r12,%r2
11327c: a7 29 00 01 lghi %r2,1
113280: e3 e0 f0 98 00 24 stg %r14,152(%r15)
113286: d7 97 c0 00 c0 00 xc 0(152,%r12),0(%r12)
11328c: c0 e5 00 28 db 4c brasl %r14,62e924 <add_e..>
113292: b2 b1 00 00 stfl 0
To fix the problem we now clear the S390_lowcore.stfl_fac_list at
startup in "head.S" for all machine types before lowcore protection
is enabled.
In addition to that the "=m" constraint is replaced by "+m".
Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Fix these:
arch/s390/kernel/perf_cpum_cf.c:180:3: warning: format '%lx'
expects argument of type 'long unsigned int',
but argument 2 has type 'int' [-Wformat]
arch/s390/kernel/perf_cpum_cf.c: In function 'cpumf_pmu_disable':
arch/s390/kernel/perf_cpum_cf.c:205:3: warning: format '%lx'
expects argument of type 'long unsigned int',
but argument 2 has type 'int' [-Wformat]
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Use braces for if/else/list_for_each_entry bodies if the body consists
of more than a single line. Otherwise I get confused and check if there
is something broken whenever I see these code snippets.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
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Merge tag 'split-asm_system_h-for-linus-20120328' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-asm_system
Pull "Disintegrate and delete asm/system.h" from David Howells:
"Here are a bunch of patches to disintegrate asm/system.h into a set of
separate bits to relieve the problem of circular inclusion
dependencies.
I've built all the working defconfigs from all the arches that I can
and made sure that they don't break.
The reason for these patches is that I recently encountered a circular
dependency problem that came about when I produced some patches to
optimise get_order() by rewriting it to use ilog2().
This uses bitops - and on the SH arch asm/bitops.h drags in
asm-generic/get_order.h by a circuituous route involving asm/system.h.
The main difficulty seems to be asm/system.h. It holds a number of
low level bits with no/few dependencies that are commonly used (eg.
memory barriers) and a number of bits with more dependencies that
aren't used in many places (eg. switch_to()).
These patches break asm/system.h up into the following core pieces:
(1) asm/barrier.h
Move memory barriers here. This already done for MIPS and Alpha.
(2) asm/switch_to.h
Move switch_to() and related stuff here.
(3) asm/exec.h
Move arch_align_stack() here. Other process execution related bits
could perhaps go here from asm/processor.h.
(4) asm/cmpxchg.h
Move xchg() and cmpxchg() here as they're full word atomic ops and
frequently used by atomic_xchg() and atomic_cmpxchg().
(5) asm/bug.h
Move die() and related bits.
(6) asm/auxvec.h
Move AT_VECTOR_SIZE_ARCH here.
Other arch headers are created as needed on a per-arch basis."
Fixed up some conflicts from other header file cleanups and moving code
around that has happened in the meantime, so David's testing is somewhat
weakened by that. We'll find out anything that got broken and fix it..
* tag 'split-asm_system_h-for-linus-20120328' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-asm_system: (38 commits)
Delete all instances of asm/system.h
Remove all #inclusions of asm/system.h
Add #includes needed to permit the removal of asm/system.h
Move all declarations of free_initmem() to linux/mm.h
Disintegrate asm/system.h for OpenRISC
Split arch_align_stack() out from asm-generic/system.h
Split the switch_to() wrapper out of asm-generic/system.h
Move the asm-generic/system.h xchg() implementation to asm-generic/cmpxchg.h
Create asm-generic/barrier.h
Make asm-generic/cmpxchg.h #include asm-generic/cmpxchg-local.h
Disintegrate asm/system.h for Xtensa
Disintegrate asm/system.h for Unicore32 [based on ver #3, changed by gxt]
Disintegrate asm/system.h for Tile
Disintegrate asm/system.h for Sparc
Disintegrate asm/system.h for SH
Disintegrate asm/system.h for Score
Disintegrate asm/system.h for S390
Disintegrate asm/system.h for PowerPC
Disintegrate asm/system.h for PA-RISC
Disintegrate asm/system.h for MN10300
...
Pull s390 patches part 2 from Martin Schwidefsky:
"Some minor improvements and one additional feature for the 3.4 merge
window: Hendrik added perf support for the s390 CPU counters."
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
[S390] register cpu devices for SMP=n
[S390] perf: add support for s390x CPU counters
[S390] oprofile: Allow multiple users of the measurement alert interrupt
[S390] qdio: log all adapter characteristics
[S390] Remove unncessary export of arch_pick_mmap_layout
The motivation for this patchset was that I was looking at a way for a
qemu-kvm process, to exclude the guest memory from its core dump, which
can be quite large. There are already a number of filter flags in
/proc/<pid>/coredump_filter, however, these allow one to specify 'types'
of kernel memory, not specific address ranges (which is needed in this
case).
Since there are no more vma flags available, the first patch eliminates
the need for the 'VM_ALWAYSDUMP' flag. The flag is used internally by
the kernel to mark vdso and vsyscall pages. However, it is simple
enough to check if a vma covers a vdso or vsyscall page without the need
for this flag.
The second patch then replaces the 'VM_ALWAYSDUMP' flag with a new
'VM_NODUMP' flag, which can be set by userspace using new madvise flags:
'MADV_DONTDUMP', and unset via 'MADV_DODUMP'. The core dump filters
continue to work the same as before unless 'MADV_DONTDUMP' is set on the
region.
The qemu code which implements this features is at:
http://people.redhat.com/~jbaron/qemu-dump/qemu-dump.patch
In my testing the qemu core dump shrunk from 383MB -> 13MB with this
patch.
I also believe that the 'MADV_DONTDUMP' flag might be useful for
security sensitive apps, which might want to select which areas are
dumped.
This patch:
The VM_ALWAYSDUMP flag is currently used by the coredump code to
indicate that a vma is part of a vsyscall or vdso section. However, we
can determine if a vma is in one these sections by checking it against
the gate_vma and checking for a non-NULL return value from
arch_vma_name(). Thus, freeing a valuable vma bit.
Signed-off-by: Jason Baron <jbaron@redhat.com>
Acked-by: Roland McGrath <roland@hack.frob.com>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Avi Kivity <avi@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add a perf PMU to access the CPU-measurement counter facility CPUM CF.
CPUM CF provides multiple counter sets for measuring generic,
problem-state, and crypto activaties. Also an extended counter set for
the IBM System z10 and IBM z196 mainframes is available.
Counters from the basic and problem-state counter set are mapped to
generic perf hardware events. Other counters are accessible through
raw events.
For a list of available counter sets and counters, see:
- The Load-Program-Parameter and the CPU-Measurement Facilities (SA23-2260)
- The CPU-Measurement Facility Extended Counters Definition for
z10 and z196 (SA23-2261)
Reviewed-by: Jan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Prepare the measurement facility which is currently only used by oprofile
for multiple users. To achieve that the measurement alert interrupt control
bit needs to be protected. The measurement alert definitions are moved
to a header file and an interrupt mask is added so that users can discard
interrupts if they are for a different measurement subsystem.
Reviewed-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Pull s390 patches from Martin Schwidefsky:
"The biggest patch is the rework of the smp code, something I wanted to
do for some time. There are some patches for our various dump methods
and one new thing: z/VM LGR detection. LGR stands for linux-guest-
relocation and is the guest migration feature of z/VM. For debugging
purposes we keep a log of the systems where a specific guest has lived."
Fix up trivial conflict in arch/s390/kernel/smp.c due to the scheduler
cleanup having removed some code next to removed s390 code.
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
[S390] kernel: Pass correct stack for smp_call_ipl_cpu()
[S390] Ensure that vmcore_info pointer is never accessed directly
[S390] dasd: prevent validate server for offline devices
[S390] Remove monolithic build option for zcrypt driver.
[S390] stack dump: fix indentation in output
[S390] kernel: Add OS info memory interface
[S390] Use block_sigmask()
[S390] kernel: Add z/VM LGR detection
[S390] irq: external interrupt code passing
[S390] irq: set __ARCH_IRQ_EXIT_IRQS_DISABLED
[S390] zfcpdump: Implement async sdias event processing
[S390] Use copy_to_absolute_zero() instead of "stura/sturg"
[S390] rework idle code
[S390] rework smp code
[S390] rename lowcore field
[S390] Fix gcc 4.6.0 compile warning
Pull scheduler changes for v3.4 from Ingo Molnar
* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (27 commits)
printk: Make it compile with !CONFIG_PRINTK
sched/x86: Fix overflow in cyc2ns_offset
sched: Fix nohz load accounting -- again!
sched: Update yield() docs
printk/sched: Introduce special printk_sched() for those awkward moments
sched/nohz: Correctly initialize 'next_balance' in 'nohz' idle balancer
sched: Cleanup cpu_active madness
sched: Fix load-balance wreckage
sched: Clean up parameter passing of proc_sched_autogroup_set_nice()
sched: Ditch per cgroup task lists for load-balancing
sched: Rename load-balancing fields
sched: Move load-balancing arguments into helper struct
sched/rt: Do not submit new work when PI-blocked
sched/rt: Prevent idle task boosting
sched/wait: Add __wake_up_all_locked() API
sched/rt: Document scheduler related skip-resched-check sites
sched/rt: Use schedule_preempt_disabled()
sched/rt: Add schedule_preempt_disabled()
sched/rt: Do not throttle when PI boosting
sched/rt: Keep period timer ticking when rt throttling is active
...
Pull RCU changes for v3.4 from Ingo Molnar. The major features of this
series are:
- making RCU more aggressive about entering dyntick-idle mode in order
to improve energy efficiency
- converting a few more call_rcu()s to kfree_rcu()s
- applying a number of rcutree fixes and cleanups to rcutiny
- removing CONFIG_SMP #ifdefs from treercu
- allowing RCU CPU stall times to be set via sysfs
- adding CPU-stall capability to rcutorture
- adding more RCU-abuse diagnostics
- updating documentation
- fixing yet more issues located by the still-ongoing top-to-bottom
inspection of RCU, this time with a special focus on the CPU-hotplug
code path.
* 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (48 commits)
rcu: Stop spurious warnings from synchronize_sched_expedited
rcu: Hold off RCU_FAST_NO_HZ after timer posted
rcu: Eliminate softirq-mediated RCU_FAST_NO_HZ idle-entry loop
rcu: Add RCU_NONIDLE() for idle-loop RCU read-side critical sections
rcu: Allow nesting of rcu_idle_enter() and rcu_idle_exit()
rcu: Remove redundant check for rcu_head misalignment
PTR_ERR should be called before its argument is cleared.
rcu: Convert WARN_ON_ONCE() in rcu_lock_acquire() to lockdep
rcu: Trace only after NULL-pointer check
rcu: Call out dangers of expedited RCU primitives
rcu: Rework detection of use of RCU by offline CPUs
lockdep: Add CPU-idle/offline warning to lockdep-RCU splat
rcu: No interrupt disabling for rcu_prepare_for_idle()
rcu: Move synchronize_sched_expedited() to rcutree.c
rcu: Check for illegal use of RCU from offlined CPUs
rcu: Update stall-warning documentation
rcu: Add CPU-stall capability to rcutorture
rcu: Make documentation give more realistic rcutorture duration
rcutorture: Permit holding off CPU-hotplug operations during boot
rcu: Print scheduling-clock information on RCU CPU stall-warning messages
...
Currently pcpu_devices->panic_stack is passed to pcpu_delegate() in
smp_call_ipl_cpu(). This is wrong because pcpu_delegate() expects
the bottom (high address) of the stack and pcpu_devices->panic_stack
points to the top (low address). We now pass the bottom of the stack
which is pcpu_devices->panic_stack + PAGE_SIZE.
Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Stepan found:
CPU0 CPUn
_cpu_up()
__cpu_up()
boostrap()
notify_cpu_starting()
set_cpu_online()
while (!cpu_active())
cpu_relax()
<PREEMPT-out>
smp_call_function(.wait=1)
/* we find cpu_online() is true */
arch_send_call_function_ipi_mask()
/* wait-forever-more */
<PREEMPT-in>
local_irq_enable()
cpu_notify(CPU_ONLINE)
sched_cpu_active()
set_cpu_active()
Now the purpose of cpu_active is mostly with bringing down a cpu, where
we mark it !active to avoid the load-balancer from moving tasks to it
while we tear down the cpu. This is required because we only update the
sched_domain tree after we brought the cpu-down. And this is needed so
that some tasks can still run while we bring it down, we just don't want
new tasks to appear.
On cpu-up however the sched_domain tree doesn't yet include the new cpu,
so its invisible to the load-balancer, regardless of the active state.
So instead of setting the active state after we boot the new cpu (and
consequently having to wait for it before enabling interrupts) set the
cpu active before we set it online and avoid the whole mess.
Reported-by: Stepan Moskovchenko <stepanm@codeaurora.org>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1323965362.18942.71.camel@twins
Signed-off-by: Ingo Molnar <mingo@elte.hu>
The first line of a stack dump has a wrong (no) indentation.
Just fix this after more than 10 years.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
In order to allow kdump based stand-alone dump, some information
has to be passed from the old kernel to the new dump kernel. This
is done via a the struct "os_info" that contains the following fields:
* crashkernel base and size
* reipl block
* vmcoreinfo
* init function
A pointer to os_info is stored at a well known storage location
and the whole structure as well as all fields are secured with
checksums.
Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Use the new helper function introduced in commit 5e6292c0f2
("signal: add block_sigmask() for adding sigmask to current->blocked")
which centralises the code for updating current->blocked after
successfully delivering a signal and reduces the amount of duplicate
code across architectures.
In the past some architectures got this code wrong, so using this
helper function should stop that from happening again.
Cc: Oleg Nesterov <oleg@redhat.com>
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: linux-s390@vger.kernel.org
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Currently the following mechanisms are available to move active
Linux on System z instances between machines:
* z/VM 6.2 SSI (Single System Image)
* Suspend/resume
For moving Linux instances in this patch the term LGR (Linux Guest
Relocation) is used. Because such an operation is critical, it
should be detectable from Linux. With this patch for both, a live
system and a kernel dump, the information about LGRs is accessible.
To identify a guest, stsi and stfle data is used. A new function
lgr_info_log() compares the current data (lgr_info_cur) with the
last recorded one (lgr_info_last). In case the two data sets differ,
lgr_info_cur is logged to the "lgr" s390dbf.
The following trigger points call lgr_info_log():
* panic
* die
* kdump
* LGR timer
* PSW restart
* QDIO recovery
* resume
This patch also changes the s390dbf hex_ascii view. Now only printable ASCII
characters are shown.
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The external interrupt handlers have a parameter called ext_int_code.
Besides the name this paramter does not only contain the ext_int_code
but in addition also the "cpu address" (POP) which caused the external
interrupt.
To make the code a bit more obvious pass a struct instead so the called
function can easily distinguish between external interrupt code and
cpu address. The cpu address field however is named "subcode" since
some external interrupt sources do not pass a cpu address but a
different parameter (or none at all).
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Use the new copy_to_absolute_zero() function instead of manual "stura"
and "sturg" to make the code shorter and more readable.
Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Whenever the cpu loads an enabled wait PSW it will appear as idle to the
underlying host system. The code in default_idle calls vtime_stop_cpu
which does the necessary voodoo to get the cpu time accounting right.
The udelay code just loads an enabled wait PSW. To correct this rework
the vtime_stop_cpu/vtime_start_cpu logic and move the difficult parts
to entry[64].S, vtime_stop_cpu can now be called from anywhere and
vtime_start_cpu is gone. The correction of the cpu time during wakeup
from an enabled wait PSW is done with a critical section in entry[64].S.
As vtime_start_cpu is gone, s390_idle_check can be removed as well.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Define struct pcpu and merge some of the NR_CPUS arrays into it, including
__cpu_logical_map, current_set and smp_cpu_state. Split smp related
functions to those operating on physical cpus and the functions operating
on a logical cpu number. Make the functions for physical cpus use a
pointer to a struct pcpu. This hides the knowledge about cpu addresses in
smp.c, entry[64].S and swsusp_asm64.S, thus remove the sigp.h header.
The PSW restart mechanism is used to start secondary cpus, calling a
function on an online cpu, calling a function on the ipl cpu, and for
the nmi signal. Replace the different assembler functions with a
single function restart_int_handler. The new entry point calls a function
whose pointer is stored in the lowcore of the target cpu and it can wait
for the source cpu to stop. This covers all existing use cases.
Overall the code is now simpler and there are ~380 lines less code.
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The 16 bit value at the lowcore location with offset 0x84 is the
cpu address that is associated with an external interrupt. Rename
the field from cpu_addr to ext_cpu_addr to make that clear.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
With gcc 4.6.0 we get a false compile warning:
arch/s390/kernel/setup.c: In function 'setup_arch':
arch/s390/kernel/setup.c:767:3: warning: 'msg' may be used
uninitialized in this function [-Wuninitialized]
arch/s390/kernel/setup.c:753:8: note: 'msg' was declared here
This patch makes gcc quiet.
Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Pull s390 fixes from Martin Schwidefsky
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
[S390] memory hotplug: prevent memory zone interleave
[S390] crash_dump: remove duplicate include
[S390] KEYS: Enable the compat keyctl wrapper on s390x
The major features of this series are:
- making RCU more aggressive about entering dyntick-idle mode in order to
improve energy efficiency
- converting a few more call_rcu()s to kfree_rcu()s
- applying a number of rcutree fixes and cleanups to rcutiny
- removing CONFIG_SMP #ifdefs from treercu
- allowing RCU CPU stall times to be set via sysfs
- adding CPU-stall capability to rcutorture
- adding more RCU-abuse diagnostics
- updating documentation
- fixing yet more issues located by the still-ongoing top-to-bottom
inspection of RCU, this time with a special focus on the
CPU-hotplug code path.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
The new is_compat_task() define for the !COMPAT case in
include/linux/compat.h conflicts with a similar define in
arch/s390/include/asm/compat.h.
This is the minimal patch which fixes the build issues.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
arch/s390/kernel/crash_dump.c included 'linux/crash_dump.h' twice,
remove the duplicate.
Signed-off-by: Danny Kukawka <danny.kukawka@bisect.de>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The 'poll()' system call timeout parameter is supposed to be 'int', not
'long'.
Now, the reason this matters is that right now 32-bit compat mode is
broken on at least x86-64, because the 32-bit code just calls
'sys_poll()' directly on x86-64, and the 32-bit argument will have been
zero-extended, turning a signed 'int' into a large unsigned 'long'
value.
We could just introduce a 'compat_sys_poll()' function for this, and
that may eventually be what we have to do, but since the actual standard
poll() semantics is *supposed* to be 'int', and since at least on x86-64
glibc sign-extends the argument before invocing the system call (so
nobody can actually use a 64-bit timeout value in user space _anyway_,
even in 64-bit binaries), the simpler solution would seem to be to just
fix the definition of the system call to match what it should have been
from the very start.
If it turns out that somebody somehow circumvents the user-level libc
64-bit sign extension and actually uses a large unsigned 64-bit timeout
despite that not being how poll() is supposed to work, we will need to
do the compat_sys_poll() approach.
Reported-by: Thomas Meyer <thomas@m3y3r.de>
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The call_rcu() in unregister_external_interrupt() invokes
ext_int_hash_update(), which just does a kfree(). Convert the
call_rcu() to kfree_rcu(), allowing ext_int_hash_update() to
be eliminated.
Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
The conversion of the ktime to a value suitable for the clock comparator
does not take changes to wall_to_monotonic into account. In fact the
conversion just needs the boot clock (sched_clock_base_cc) and the
total_sleep_time.
This is applicable to 3.2+ kernels.
CC: stable@vger.kernel.org
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Avoid calling wake_up() from our NMI "bottom halve" from RCU extended
quiescent state in idle. wake_up() has RCU read-side critical sections
but this will be completely ignored by RCU if the cpu is in extended
quiescent state.
Which means that whatever object is being accessed from within the
read-side critical section can be freed concurrently from a different
cpu.
So make sure we leave extended quiescent state before calling wake_up().
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The vmlinux file for s390 contains a currently unused entry point,
which is specified in two different locations: the linker script
and the makefile. As it happens both definitions are different and
the linker file is broken (_start does not exist) and the makefile
specifies an entry point which makes no sense (the SALIPL loader
entry point).
So lets get rid of one definition (the makefile) and use the entry
point of all other ipl methods (0x10000 -> startup) to be consistent.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/audit: (29 commits)
audit: no leading space in audit_log_d_path prefix
audit: treat s_id as an untrusted string
audit: fix signedness bug in audit_log_execve_info()
audit: comparison on interprocess fields
audit: implement all object interfield comparisons
audit: allow interfield comparison between gid and ogid
audit: complex interfield comparison helper
audit: allow interfield comparison in audit rules
Kernel: Audit Support For The ARM Platform
audit: do not call audit_getname on error
audit: only allow tasks to set their loginuid if it is -1
audit: remove task argument to audit_set_loginuid
audit: allow audit matching on inode gid
audit: allow matching on obj_uid
audit: remove audit_finish_fork as it can't be called
audit: reject entry,always rules
audit: inline audit_free to simplify the look of generic code
audit: drop audit_set_macxattr as it doesn't do anything
audit: inline checks for not needing to collect aux records
audit: drop some potentially inadvisable likely notations
...
Use evil merge to fix up grammar mistakes in Kconfig file.
Bad speling and horrible grammar (and copious swearing) is to be
expected, but let's keep it to commit messages and comments, rather than
expose it to users in config help texts or printouts.
Every arch calls:
if (unlikely(current->audit_context))
audit_syscall_entry()
which requires knowledge about audit (the existance of audit_context) in
the arch code. Just do it all in static inline in audit.h so that arch's
can remain blissfully ignorant.
Signed-off-by: Eric Paris <eparis@redhat.com>
The audit system previously expected arches calling to audit_syscall_exit to
supply as arguments if the syscall was a success and what the return code was.
Audit also provides a helper AUDITSC_RESULT which was supposed to simplify things
by converting from negative retcodes to an audit internal magic value stating
success or failure. This helper was wrong and could indicate that a valid
pointer returned to userspace was a failed syscall. The fix is to fix the
layering foolishness. We now pass audit_syscall_exit a struct pt_reg and it
in turns calls back into arch code to collect the return value and to
determine if the syscall was a success or failure. We also define a generic
is_syscall_success() macro which determines success/failure based on if the
value is < -MAX_ERRNO. This works for arches like x86 which do not use a
separate mechanism to indicate syscall failure.
We make both the is_syscall_success() and regs_return_value() static inlines
instead of macros. The reason is because the audit function must take a void*
for the regs. (uml calls theirs struct uml_pt_regs instead of just struct
pt_regs so audit_syscall_exit can't take a struct pt_regs). Since the audit
function takes a void* we need to use static inlines to cast it back to the
arch correct structure to dereference it.
The other major change is that on some arches, like ia64, MIPS and ppc, we
change regs_return_value() to give us the negative value on syscall failure.
THE only other user of this macro, kretprobe_example.c, won't notice and it
makes the value signed consistently for the audit functions across all archs.
In arch/sh/kernel/ptrace_64.c I see that we were using regs[9] in the old
audit code as the return value. But the ptrace_64.h code defined the macro
regs_return_value() as regs[3]. I have no idea which one is correct, but this
patch now uses the regs_return_value() function, so it now uses regs[3].
For powerpc we previously used regs->result but now use the
regs_return_value() function which uses regs->gprs[3]. regs->gprs[3] is
always positive so the regs_return_value(), much like ia64 makes it negative
before calling the audit code when appropriate.
Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: H. Peter Anvin <hpa@zytor.com> [for x86 portion]
Acked-by: Tony Luck <tony.luck@intel.com> [for ia64]
Acked-by: Richard Weinberger <richard@nod.at> [for uml]
Acked-by: David S. Miller <davem@davemloft.net> [for sparc]
Acked-by: Ralf Baechle <ralf@linux-mips.org> [for mips]
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> [for ppc]
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (31 commits)
[S390] disassembler: mark exception causing instructions
[S390] Enable exception traces by default
[S390] return address of compat signals
[S390] sysctl: get rid of dead declaration
[S390] dasd: fix fixpoint divide exception in define_extent
[S390] dasd: add sanity check to detect path connection error
[S390] qdio: fix kernel panic for zfcp 31-bit
[S390] Add s390x description to Documentation/kdump/kdump.txt
[S390] Add VMCOREINFO_SYMBOL(high_memory) to vmcoreinfo
[S390] dasd: fix expiration handling for recovery requests
[S390] outstanding interrupts vs. smp_send_stop
[S390] ipc: call generic sys_ipc demultiplexer
[S390] zcrypt: Fix error return codes.
[S390] zcrypt: Rework length parameter checking.
[S390] cleanup trap handling
[S390] Remove Kerntypes leftovers
[S390] topology: increase poll frequency if change is anticipated
[S390] entry[64].S improvements
[S390] make arch/s390 subdirectories depend on config option
[S390] kvm: move cmf host id constant out of lowcore
...
Fix up conflicts in arch/s390/kernel/{smp.c,topology.c} due to the
sysdev removal clashing with "topology: get rid of ifdefs" which moved
some of that code around.
* 'for-linus2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (165 commits)
reiserfs: Properly display mount options in /proc/mounts
vfs: prevent remount read-only if pending removes
vfs: count unlinked inodes
vfs: protect remounting superblock read-only
vfs: keep list of mounts for each superblock
vfs: switch ->show_options() to struct dentry *
vfs: switch ->show_path() to struct dentry *
vfs: switch ->show_devname() to struct dentry *
vfs: switch ->show_stats to struct dentry *
switch security_path_chmod() to struct path *
vfs: prefer ->dentry->d_sb to ->mnt->mnt_sb
vfs: trim includes a bit
switch mnt_namespace ->root to struct mount
vfs: take /proc/*/mounts and friends to fs/proc_namespace.c
vfs: opencode mntget() mnt_set_mountpoint()
vfs: spread struct mount - remaining argument of next_mnt()
vfs: move fsnotify junk to struct mount
vfs: move mnt_devname
vfs: move mnt_list to struct mount
vfs: switch pnode.h macros to struct mount *
...
* 'driver-core-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (73 commits)
arm: fix up some samsung merge sysdev conversion problems
firmware: Fix an oops on reading fw_priv->fw in sysfs loading file
Drivers:hv: Fix a bug in vmbus_driver_unregister()
driver core: remove __must_check from device_create_file
debugfs: add missing #ifdef HAS_IOMEM
arm: time.h: remove device.h #include
driver-core: remove sysdev.h usage.
clockevents: remove sysdev.h
arm: convert sysdev_class to a regular subsystem
arm: leds: convert sysdev_class to a regular subsystem
kobject: remove kset_find_obj_hinted()
m86k: gpio - convert sysdev_class to a regular subsystem
mips: txx9_sram - convert sysdev_class to a regular subsystem
mips: 7segled - convert sysdev_class to a regular subsystem
sh: dma - convert sysdev_class to a regular subsystem
sh: intc - convert sysdev_class to a regular subsystem
power: suspend - convert sysdev_class to a regular subsystem
power: qe_ic - convert sysdev_class to a regular subsystem
power: cmm - convert sysdev_class to a regular subsystem
s390: time - convert sysdev_class to a regular subsystem
...
Fix up conflicts with 'struct sysdev' removal from various platform
drivers that got changed:
- arch/arm/mach-exynos/cpu.c
- arch/arm/mach-exynos/irq-eint.c
- arch/arm/mach-s3c64xx/common.c
- arch/arm/mach-s3c64xx/cpu.c
- arch/arm/mach-s5p64x0/cpu.c
- arch/arm/mach-s5pv210/common.c
- arch/arm/plat-samsung/include/plat/cpu.h
- arch/powerpc/kernel/sysfs.c
and fix up cpu_is_hotpluggable() as per Greg in include/linux/cpu.h
This resolves the conflict in the arch/arm/mach-s3c64xx/s3c6400.c file,
and it fixes the build error in the arch/x86/kernel/microcode_core.c
file, that the merge did not catch.
The microcode_core.c patch was provided by Stephen Rothwell
<sfr@canb.auug.org.au> who was invaluable in the merge issues involved
with the large sysdev removal process in the driver-core tree.
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (64 commits)
cpu: Export cpu_up()
rcu: Apply ACCESS_ONCE() to rcu_boost() return value
Revert "rcu: Permit rt_mutex_unlock() with irqs disabled"
docs: Additional LWN links to RCU API
rcu: Augment rcu_batch_end tracing for idle and callback state
rcu: Add rcutorture tests for srcu_read_lock_raw()
rcu: Make rcutorture test for hotpluggability before offlining CPUs
driver-core/cpu: Expose hotpluggability to the rest of the kernel
rcu: Remove redundant rcu_cpu_stall_suppress declaration
rcu: Adaptive dyntick-idle preparation
rcu: Keep invoking callbacks if CPU otherwise idle
rcu: Irq nesting is always 0 on rcu_enter_idle_common
rcu: Don't check irq nesting from rcu idle entry/exit
rcu: Permit dyntick-idle with callbacks pending
rcu: Document same-context read-side constraints
rcu: Identify dyntick-idle CPUs on first force_quiescent_state() pass
rcu: Remove dynticks false positives and RCU failures
rcu: Reduce latency of rcu_prepare_for_idle()
rcu: Eliminate RCU_FAST_NO_HZ grace-period hang
rcu: Avoid needlessly IPIing CPUs at GP end
...
If an exception happens the PSW either points to the instruction that
caused the exception or to the instruction that follows the exception
causing instruction, depending on the exception type.
Since the inkernel disassembler adds a ">" in front of the disassembly
many people assume incorrectly that the instruction that is pointed to
must be the cause of the exception. To make people aware that this is
not necessarily the case add a different character in front of the
disassembled instruction that precedes the current instructions.
The output now looks like this:
Krnl PSW : 0704200180000000 0000000000120de8 (test_function+0x0/0x100)
R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:0 CC:2 PM:0 EA:3
Krnl GPRS: 000003ff00000000 0000000000120de4 000000000091bb40 0000000000000001
000003fffd2ea000 0000000030fb7df8 0000000030fb7f10 000003ffffa113c8
000000000091bb40 000003fffd2ea000 0000000000000002 0000000030fb7f10
000000003f290240 0000000000606220 00000000002cfb5c 0000000030fb7d58
Krnl Code: 0000000000120ddc: b90400a9 lgr %r10,%r9
0000000000120de0: a7f4ff88 brc 15,120cf0
#0000000000120de4: a7f40001 brc 15,120de6
>0000000000120de8: a7f13f80 tmll %r15,16256
0000000000120dec: eb8ff0580024 stmg %r8,%r15,88(%r15)
0000000000120df2: a7840001 brc 8,120df4
0000000000120df6: b90400ef lgr %r14,%r15
0000000000120dfa: a7fbffb8 aghi %r15,-72
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Enable exception traces by default so that early user space breakage
(e.g. broken code in initrd) can be easily indentified.
If not needed afterwards it can be disabled by writing '0' in one of
these two files:
/proc/sys/kernel/userprocess_debug
/proc/sys/debug/exception-trace
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
A 31-bit kernel always sets the high order bit in the return address
for a signal handler.
git commit d4e81b35b8 "[S390] allow all addressing modes" makes
sure that the high order bit is set in the signal return address for
standard signals of a 31-bit compat process but fails to do the same
for real-time signals. To make things consistent the bit needs to be
set by setup_rt_frame32 as well.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Currently the vmalloc_start address (or better end of real memory) for s390x
is obtained by makedumpfile using vmlist.addr symbol, which is not correct.
The correct vmalloc_start address can be obtained using 'high_memory' symbol.
This patch adds the high_memory symbol to vmcoreinfo.
Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The panic function will first print the panic message to the console,
then stop additional cpus with smp_send_stop and finally call the
function on the panic notifier list.
In case of an I/O based console the panic message will cause I/O to
be started and a function on the panic notifier list will wait for the
completion of the I/O. That does not work if an I/O completion interrupt
has already been delivered to a cpu that is then stopped by smp_send_stop.
To break this cyclic dependency add code to smp_send_stop that gives
the additional cpu the opportunity to complete outstanding interrupts.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Call generic IPC demultiplexer instead of having a nearly identical
s390 variant. Also make sure that native and compat handling now have
the same behaviour.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Move the program interruption code and the translation exception identifier
to the pt_regs structure as 'int_code' and 'int_parm_long' and make the
first level interrupt handler in entry[64].S store the two values. That
makes it possible to drop 'prot_addr' and 'trap_no' from the thread_struct
and to reduce the number of arguments to a lot of functions. Finally
un-inline do_trap. Overall this saves 5812 bytes in the .text section of
the 64 bit kernel.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Increase cpu topology change poll frequency if a change is anticipated.
Otherwise a user might be a bit confused to have to wait up to a minute
in order to see a change this should be visible immediatly.
However there is no guarantee that the change will happen during the
time frame the poll frequency is increased.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Another round of cleanup for entry[64].S, in particular the program check
handler looks more reasonable now. The code size for the 31 bit kernel
has been reduced by 616 byte and by 528 byte for the 64 bit version.
Even better the code is a bit faster as well.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
There is no reason for the cpu-measurement-facility host id constant to
reside in the lowcore where space is precious. Use an entry in the literal
pool in HANDLE_SIE_INTERCEPT and a stack slot in sie64a.
While we are at it replace the id -1 with 0 to indicate host execution.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cleanup z10 topology handling. This adds some more code but hopefully
the result is more readable and easier to maintain.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Remove all ifdefs from topology code and also only compile it for the
CONFIG_SCHED_BOOK case. The new code selects SCHED_MC if SCHED_BOOK is
selected. SCHED_MC without SCHED_BOOK is not possible anymore.
Furthermore various sysfs attributes are not available anymore for the
!SCHED_BOOK case. In particular all attributes that correspond to
CPU polarization.
But since all real world kernels have SCHED_BOOK selected anyway this
doesn't matter too much.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Currently, when smp_switch_to_ipl_cpu() is done, the backchain in the dump
analysis tool crash looks like the following:
#0 [1f746e70] __machine_kexec at 11dd92
#1 [1f746eb8] smp_restart_cpu at 11820e
#0 [00907eb0] cpu_idle at 10602e
#1 [00907ef8] start_kernel at 979a08
It would be good to see the registers of the interrupted function.
To achieve this, the backchain on the new stack has to be set to zero.
This looks then like the following:
#0 [1f746e70] __machine_kexec at 11dd8e
#1 [1f746eb8] smp_restart_cpu at 11820a
PSW: 0706000180000000 00000000005c6fe6 (vtime_stop_cpu+134)
GPRS: 0000000000000000 00000000005c6fe6 0000000001ad0228 0000000001ad0248
0000000000907f08 0000000001ad0b40 0000000000979344 0000000000000000
00000000009c0000 00000000009c0010 00000000009ab024 0000000001ad0200
0000000001ad0238 00000000005cc9d8 000000000010602e 0000000000907e68
#0 [00907eb0] cpu_idle at 10602e
#1 [00907ef8] start_kernel at 979a08
In addition to this, now also the correct PSW is stored in the pt_regs
structure that is located at the start of the panic stack.
Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The kernel address space of a 64 bit kernel currently uses a three level
page table and the vmemmap array has a fixed address and a fixed maximum
size. A three level page table is good enough for systems with less than
3.8TB of memory, for bigger systems four page table levels need to be
used. Each page table level costs a bit of performance, use 3 levels for
normal systems and 4 levels only for the really big systems.
To avoid bloating sparse.o too much set MAX_PHYSMEM_BITS to 46 for a
maximum of 64TB of memory.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
This patch makes the create_mem_hole() function more readable and
fixes some minor bugs (e.g. off-by-one problems).
Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The current code in setup_boot_command_line() uses a heuristic to
detect an EBCDIC command line. It checks if any of the bytes in
the command line has bit one (0x80) set. In that case it is assumed
that we have an EBCDIC string and the complete command line is
converted.
On s390 there are cases where the boot loader provides a kernel
command line that is NULL terminated, but has random data after
the NULL termination. In that case, setup_boot_command_line()
might misinterpret an ASCII string for an EBCDIC string. A
subsequent string conversion can then damage the ASCII string.
This patch solves the problem by checking for NULL termination.
If no EBCDIC character has been found until the the NULL
termination has been found, we now assume that we have an ASCII
string.
Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Mask the extint_code parameter of the smp external interrupt handler
to get the interruption code. Otherwise emergency call interrupts
erroneously might be accounted as emergency signal interrupts.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
After all sysdev classes are ported to regular driver core entities, the
sysdev implementation will be entirely removed from the kernel.
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This moves the 'cpu sysdev_class' over to a regular 'cpu' subsystem
and converts the devices to regular devices. The sysdev drivers are
implemented as subsystem interfaces now.
After all sysdev classes are ported to regular driver core entities, the
sysdev implementation will be entirely removed from the kernel.
Userspace relies on events and generic sysfs subsystem infrastructure
from sysdev devices, which are made available with this conversion.
Cc: Haavard Skinnemoen <hskinnemoen@gmail.com>
Cc: Hans-Christian Egtvedt <egtvedt@samfundet.no>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Borislav Petkov <bp@amd64.org>
Cc: Tigran Aivazian <tigran@aivazian.fsnet.co.uk>
Cc: Len Brown <lenb@kernel.org>
Cc: Zhang Rui <rui.zhang@intel.com>
Cc: Dave Jones <davej@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Russell King <rmk+kernel@arm.linux.org.uk>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: "Srivatsa S. Bhat" <srivatsa.bhat@linux.vnet.ibm.com>
Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Those two APIs were provided to optimize the calls of
tick_nohz_idle_enter() and rcu_idle_enter() into a single
irq disabled section. This way no interrupt happening in-between would
needlessly process any RCU job.
Now we are talking about an optimization for which benefits
have yet to be measured. Let's start simple and completely decouple
idle rcu and dyntick idle logics to simplify.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
It is assumed that rcu won't be used once we switch to tickless
mode and until we restart the tick. However this is not always
true, as in x86-64 where we dereference the idle notifiers after
the tick is stopped.
To prepare for fixing this, add two new APIs:
tick_nohz_idle_enter_norcu() and tick_nohz_idle_exit_norcu().
If no use of RCU is made in the idle loop between
tick_nohz_enter_idle() and tick_nohz_exit_idle() calls, the arch
must instead call the new *_norcu() version such that the arch doesn't
need to call rcu_idle_enter() and rcu_idle_exit().
Otherwise the arch must call tick_nohz_enter_idle() and
tick_nohz_exit_idle() and also call explicitly:
- rcu_idle_enter() after its last use of RCU before the CPU is put
to sleep.
- rcu_idle_exit() before the first use of RCU after the CPU is woken
up.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mike Frysinger <vapier@gentoo.org>
Cc: Guan Xuetao <gxt@mprc.pku.edu.cn>
Cc: David Miller <davem@davemloft.net>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Hans-Christian Egtvedt <hans-christian.egtvedt@atmel.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
The tick_nohz_stop_sched_tick() function, which tries to delay
the next timer tick as long as possible, can be called from two
places:
- From the idle loop to start the dytick idle mode
- From interrupt exit if we have interrupted the dyntick
idle mode, so that we reprogram the next tick event in
case the irq changed some internal state that requires this
action.
There are only few minor differences between both that
are handled by that function, driven by the ts->inidle
cpu variable and the inidle parameter. The whole guarantees
that we only update the dyntick mode on irq exit if we actually
interrupted the dyntick idle mode, and that we enter in RCU extended
quiescent state from idle loop entry only.
Split this function into:
- tick_nohz_idle_enter(), which sets ts->inidle to 1, enters
dynticks idle mode unconditionally if it can, and enters into RCU
extended quiescent state.
- tick_nohz_irq_exit() which only updates the dynticks idle mode
when ts->inidle is set (ie: if tick_nohz_idle_enter() has been called).
To maintain symmetry, tick_nohz_restart_sched_tick() has been renamed
into tick_nohz_idle_exit().
This simplifies the code and micro-optimize the irq exit path (no need
for local_irq_save there). This also prepares for the split between
dynticks and rcu extended quiescent state logics. We'll need this split to
further fix illegal uses of RCU in extended quiescent states in the idle
loop.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mike Frysinger <vapier@gentoo.org>
Cc: Guan Xuetao <gxt@mprc.pku.edu.cn>
Cc: David Miller <davem@davemloft.net>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Hans-Christian Egtvedt <hans-christian.egtvedt@atmel.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
s390 used early_node_map[] just to prime free_area_init_nodes(). Now
memblock can be used for the same purpose and early_node_map[] is
scheduled to be dropped. Use memblock instead.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: linux-s390@vger.kernel.org
git commit 20b40a794b "signal race with restarting system calls"
added code to the poke_user/poke_user_compat to reset the system call
restart information in the thread-info if the PSW address is changed.
The purpose of that change has been to workaround old gdbs that do
not know about the REGSET_SYSTEM_CALL. It turned out that this is not
a good idea, it makes the behaviour of the debuggee dependent on the
order of specific ptrace call, e.g. the REGSET_SYSTEM_CALL register
set needs to be written last. And the workaround does not really fix
old gdbs, inferior calls on interrupted restarting system calls do not
work either way.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The last breaking event address is a read-only value, the regset misses the
.set function. If a PTRACE_SETREGSET is done for NT_S390_LAST_BREAK we
get an oops due to a branch to zero:
Kernel BUG at 0000000000000002 verbose debug info unavailable
illegal operation: 0001 #1 SMP
...
Call Trace:
(<0000000000158294> ptrace_regset+0x184/0x188)
<00000000001595b6> ptrace_request+0x37a/0x4fc
<0000000000109a78> arch_ptrace+0x108/0x1fc
<00000000001590d6> SyS_ptrace+0xaa/0x12c
<00000000005c7a42> sysc_noemu+0x16/0x1c
<000003fffd5ec10c> 0x3fffd5ec10c
Last Breaking-Event-Address:
<0000000000158242> ptrace_regset+0x132/0x188
Add a nop .set function to prevent the branch to zero.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: stable@kernel.org
The TIF_SYSCALL bit needs to be cleared if the debugger changes the state
of the ptraced process in regard to the presence of a system call.
Otherwise the system call will be restarted although the debugger set up
an inferior call.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
In order to have the same behavior for kdump based stand-alone dump
as for the kexec method, the is_kdump_kernel() check (only true for
the kexec method) has to be replaced by the OLDMEM_BASE check (true
for both methods).
Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Make sure that all cpus in a book on a z10 appear as book siblings
and not as core siblings. This fixes some performance regressions that
appeared after the book scheduling domain got introduced.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
In ESA mode STCKF is not defined even if the facility bit is enabled.
To prevent an illegal operation we must also check if we run a 64 bit kernel.
To make the check perform well add the STCKF bit to the machine flags.
Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
When the kernel is started in kdump mode, zfcpdump should not be
initialized because both dump methods can't be used at the same time.
Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
'readelf -n' on the s390 vmlinux file generates lots of warnings about
corrupt notes. The reason is that the 'NOTE' program header has incorrect
file and memory sizes. The problem is that the section following the
NOTES section do not switch to a different phdr and they get added to
the NOTE program section. Add a dummy entry to the linker script that
switches to the data phdr before the start of the RODATA section.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* 'upstream/jump-label-noearly' of git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen:
jump-label: initialize jump-label subsystem much earlier
x86/jump_label: add arch_jump_label_transform_static()
s390/jump-label: add arch_jump_label_transform_static()
jump_label: add arch_jump_label_transform_static() to optimise non-live code updates
sparc/jump_label: drop arch_jump_label_text_poke_early()
x86/jump_label: drop arch_jump_label_text_poke_early()
jump_label: if a key has already been initialized, don't nop it out
stop_machine: make stop_machine safe and efficient to call early
jump_label: use proper atomic_t initializer
Conflicts:
- arch/x86/kernel/jump_label.c
Added __init_or_module to arch_jump_label_text_poke_early vs
removal of that function entirely
- kernel/stop_machine.c
same patch ("stop_machine: make stop_machine safe and efficient
to call early") merged twice, with whitespace fix in one version
Currently it can happen that the pre-allocated ELF header contains a wrong
memory map which would result in errors when copying /proc/vmcore.
In order to still get a valid vmcore, we (temporarily) disable the error
checking in copy_oldmem_page(). This will then produce zero pages for those
memory regions.
Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Martin Schwidefsky