The loop above the modified code only terminates when rc is a valid pointer.
A simplified version of the semantic patch that makes this change is as
follows: (http://www.emn.fr/x-info/coccinelle/)
// <smpl>
@r exists@
local idexpression x;
expression E;
position p1,p2;
@@
if (x@p1 == NULL || ...) { ... when forall
return ...; }
... when != \(x=E\|x--\|x++\|--x\|++x\|x-=E\|x+=E\|x|=E\|x&=E\|&x\)
(
x@p2 == NULL
|
x@p2 != NULL
)
// another path to the test that is not through p1?
@s exists@
local idexpression r.x;
position r.p1,r.p2;
@@
... when != x@p1
(
x@p2 == NULL
|
x@p2 != NULL
)
@fix depends on !s@
position r.p1,r.p2;
expression x,E;
statement S1,S2;
@@
(
- if ((x@p2 != NULL) || ...)
S1
|
- if ((x@p2 == NULL) && ...) S1
|
- BUG_ON(x@p2 == NULL);
)
// </smpl>
Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
This patch sets the default console device for s390.
The console= kernel parameter can be still used to switch the preferred
console to some other device. In that case, console messages are also
printed on the default console device (ttyS0).
Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Tell the compile that the clear_table inline assembly writes to the
memory referenced by *s.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
On s390 we always want to run with precise cputime accounting.
Remove the config options VIRT_TIMER and VIRT_CPU_ACCOUNTING.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Interrupts haven't been implemented. So remove the dead code.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Introduce a topology=[on|off] kernel parameter which allows to switch
cpu topology on/off. Default will be off, since it looks like that for
some workloards this doesn't behave very well (on s390).
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Add the machine types for z9-bc, z10-ec and z10-bc to the elf_platform
detection in setup_hwcaps.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Early init code clears the backchain of the initial kernel stack frame.
This is not necessary since it is pre initialized with zeros. Plus it
was broken on 64 bit since it cleared only four of eight bytes.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
This patch adds the code generation option for IBM System z10 and
adds a check in head[31,64].S to prevents the execution of a kernel
compiled for a new processor type on an old machine.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Functions which end in a BUG() statement and skip the return statement
cause compile warnings on s390, e.g.:
mm/bootmem.c: In function 'mark_bootmem':
mm/bootmem.c:321: warning: control reaches end of non-void function
To avoid the warning add an endless loop to the BUG() macro.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
disabled_wait() won't return, so add an __attribute__((noreturn)).
This will remove a false positive finding which our internal code
checker reports.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Values for the sac field have changed - update code accordingly.
Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
A kernel compile on 31 bit gives the following warnings in ptrace.c:
arch/s390/kernel/ptrace.c: In function 'peek_user':
arch/s390/kernel/ptrace.c:207: warning: unused variable 'dummy'
arch/s390/kernel/ptrace.c: In function 'poke_user':
arch/s390/kernel/ptrace.c:315: warning: unused variable 'dummy'
Getting rid of the dummy variables removes the warnings.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
This implements just the basic function tracer (_mcount) backend for s390.
The dynamic variant will come later.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Add a new proc interface /proc/service_levels that allows any code
to report a relevant service level, e.g. the microcode level of
devices, the service level of the hypervisor, etc.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
- make qdio_trace a per device view
- remove s390dbf exceptions
- remove CONFIG_QDIO_DEBUG, not needed anymore if we check for the level
before calling sprintf
- use snprintf for dbf entries
- add start markers to see if the dbf view wrapped
- add a global error view for all queues
Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
qeth needs to get the port count information before
qdio has allocated a page for the chsc operation.
Extend qdio_get_ssqd_desc() to store the data in the
specified structure.
Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
When the machine supports AP adapter interrupts polling will be
switched off at module initialization and the driver will work in
interrupt mode.
Signed-off-by: Felix Beck <felix.beck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
stfle will be needed by the ap_bus module to figure out wether the AP
queue adapter interruption facility is installed.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Since etr/stp don't need the old smp_call_function semantics anymore
we can convert s390 to the generic IPI infrastructure.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The work function dispatched with schedule_work() can be run twice
on different cpus because run_workqueue clears the WORK_STRUCT_PENDING
bit and then executes the function. Another cpu can call schedule_work()
again and run the work function a second time before the first call
is completed. This patch serialized the etr and stp work function with
a mutex.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
This converts the etr and stp code to the new stop_machine interface
which allows to synchronize all cpus without allocating any memory.
This way we get rid of the only reason why we haven't converted s390
to the generic IPI interface yet.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Add a vdso to speed up gettimeofday and clock_getres/clock_gettime for
CLOCK_REALTIME/CLOCK_MONOTONIC.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
arch_setup_additional_pages currently gets two arguments, the binary
format descripton and an indication if the process uses an executable
stack or not. The second argument is not used by anybody, it could
be removed without replacement.
What actually does make sense is to pass an indication if the process
uses the elf interpreter or not. The glibc code will not use anything
from the vdso if the process does not use the dynamic linker, so for
statically linked binaries the architecture backend can choose not
to map the vdso.
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Call rebuild_sched_domains instead of arch_reinit_sched_domains if
cpu topology changes. This leaves cpu sets alone which otherwise would
be destroyed.
If and how it makes sense to define cpu sets on a virtualized
architecture is another question.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
On s390 we have ret_from_fork jump not to the "do all work we
normally do on return from syscall" as on x86, ppc, etc., but to the
"do all such work except audit". Historical reasons - the codepath
triggered when we have AUDIT process flag set is separated from the
normall one and they converge at sysc_return, which is the common
part of post-syscall work. And does not include calling audit_syscall_exit() -
that's done in the end of sysc_tracesys path, just before that path jumps
to sysc_return.
IOW, the child returning from fork()/clone()/vfork() doesn't
call audit_syscall_exit() at all, so no matter what we do with its
audit context, we are not going to see the audit entry.
The fix is simple: have ret_from_fork go to the point just past
the call of sys_.... in the 'we have AUDIT flag set' path. There we
have (64bit variant; for 31bit the situation is the same):
sysc_tracenogo:
tm __TI_flags+7(%r9),(_TIF_SYSCALL_TRACE|_TIF_SYSCALL_AUDIT)
jz sysc_return
la %r2,SP_PTREGS(%r15) # load pt_regs
larl %r14,sysc_return # return point is sysc_return
jg do_syscall_trace_exit
which is precisely what we need - check the flag, bugger off to sysc_return
if not set, otherwise call do_syscall_trace_exit() and bugger off to
sysc_return. r9 has just been properly set by ret_from_fork itself,
so we are fine.
Tested on s390x, seems to work fine. WARNING: it's been about
16 years since my last contact with 3X0 assembler[1], so additional
review would be very welcome. I don't think I've managed to screw it
up, but...
[1] that *was* in another country and besides, the box is dead...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Common code doesn't call arch_update_cpu_topology() anymore on
cpu hotplug. But our architecture backend relied on that in order to
update the cpu_core_map. For machines without cpu topology support
this leads uninitialized cpu_core_maps for later on added cpus.
To solve this just initialize the maps with cpu_possible_map, since
that will be always valid for machines without topology support.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Impact: cleanup, avoid warning on X86_64
Fixes this warning on X86_64:
CC arch/x86/kernel/traps.o
arch/x86/kernel/traps.c:695:5: warning: "CONFIG_X86_32" is not defined
Signed-off-by: Jaswinder Singh <jaswinder@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: fix a crash/hard-reboot on certain configs while enabling cpu runtime
On some archs, the boot of a secondary cpu can have an early fragile state.
On x86-64, the pda is not initialized on the first stage of a cpu boot but
it is needed to get the cpu number and the current task pointer. This data
is needed during tracing. As they were dereferenced at this stage, we got a
crash while tracing a cpu being enabled at runtime.
Some other archs like ia64 can have such kind of issue too.
Changes on v2:
We dropped the previous solution of a per-arch called function to guess the
current state of a cpu. That could slow down the tracing.
This patch removes the -pg flag on arch/x86/kernel/cpu/common.c where
the low level cpu boot functions exist, on start_secondary() and a helper
function used at this stage.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Acked-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
The original copyright head for crc32c-intel.c is incorrect. Please merge
the patch to update it.
Signed-Off-By: Kent Liu <kent.liu@intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
there's a new ptrace arch level feature in .28:
config X86_PTRACE_BTS
bool "Branch Trace Store"
it has broken fork() handling: the old DS area gets copied over into
a new task without clearing it.
Fixes exist but they came too late:
c5dee61: x86, bts: memory accounting
bf53de9: x86, bts: add fork and exit handling
and are queued up for v2.6.29. This shows that the facility is still not
tested well enough to release into a stable kernel - disable it for now and
reactivate in .29. In .29 the hardware-branch-tracer will use the DS/BTS
facilities too - hopefully resulting in better code.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: cleanup, fix warning
This warning:
arch/x86/mm/pat.c: In function track_pfn_vma_copy:
arch/x86/mm/pat.c:701: warning: passing argument 5 of follow_phys from incompatible pointer type
Triggers because physical addresses are resource_size_t, not u64.
This really matters when calling an interface like follow_phys() which
takes a pointer to a physical address -- although on x86, being
littleendian, it would generally work anyway as long as the memory region
wasn't completely uninitialized.
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
flush_tlb_mm's "optimized" uniprocessor case of allocating a new
context for userspace is exposing a race where we can suddely return
to a syscall with the protection id and space id out of sync, trapping
on the next userspace access.
Debugged-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Tested-by: Helge Deller <deller@gmx.de>
Signed-off-by: Kyle McMartin <kyle@mcmartin.ca>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
