Semaphores are no longer performance-critical, so a generic C
implementation is better for maintainability, debuggability and
extensibility. Thanks to Peter Zijlstra for fixing the lockdep
warning. Thanks to Harvey Harrison for pointing out that the
unlikely() was unnecessary.
Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
1) ptrace should pass 'current' to task_user_regset_view()
2) When fetching general registers using a 64-bit view, and
the target is 32-bit, we have to convert.
3) Skip the whole register window get/set code block if
the user isn't asking to access anything in there.
Otherwise we have problems if the user doesn't have
an address space setup. Fetching ptrace register is
still valid at such a time, and ptrace does not try
to access the register window area of the regset.
Signed-off-by: David S. Miller <davem@davemloft.net>
The calculation of the FPU reg save area pointer
was wrong.
Based upon an OOPS report from Tom Callaway.
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Some IOMMUs allocate memory areas spanning LLD's segment boundary limit. It
forces low level drivers to have a workaround to adjust scatter lists that the
IOMMU builds. We are in the process of making all the IOMMUs respect the
segment boundary limits to remove such work around in LLDs.
SPARC64 IOMMUs were rewritten to use the IOMMU helper functions and the commit
89c94f2f70 made the IOMMUs not allocate memory
areas spanning the segment boundary limit.
However, SPARC64 IOMMUs allocate memory areas first then try to merge them
(while some IOMMUs walk through all the sg entries to see how they can be
merged first and allocate memory areas). So SPARC64 IOMMUs also need the
boundary limit checking when they try to merge sg entries.
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Sparse still doesn't like the funny cast we make from a scalar to a
"union semun" (which is correct by the C language and in particular
works with the sparc64 calling conventions, but sparse doesn't grok
that yet).
Signed-off-by: David S. Miller <davem@davemloft.net>
Add 'UL' markers to DCU_* macros.
Declare C functions called from assembler in entry.h
Declare C functions called from within the sparc64 arch
code in include/asm-sparc64/*.h headers as appropriate.
Remove unused routines in traps.c
Signed-off-by: David S. Miller <davem@davemloft.net>
We create a local header file entry.h, under arch/sparc64/kernel/,
that we can use to declare routines either defined in assembler
or only invoked from assembler. As well as other data objects
which are private to the inner sparc64 kernel arch code.
Signed-off-by: David S. Miller <davem@davemloft.net>
Doing a 'flushw' every stack trace capture creates so much overhead
that it makes lockdep next to unusable.
We only care about the frame pointer chain and the function caller
program counters, so flush those by hand to the stack frame.
This is significantly more efficient than a 'flushw' because:
1) We only save 16 bytes per active register window to the stack.
2) This doesn't push the entire register window context of the current
call chain out of the cpu, forcing register window fill traps as we
return back down.
Note that we can't use 'restore' and 'save' instructions to move
around the register windows because that wouldn't work on Niagara
processors. They optimize 'save' into a new register window by
simply clearing out the registers instead of pulling them in from
the on-chip register window backing store.
Based upon a report by Tom Callaway.
Signed-off-by: David S. Miller <davem@davemloft.net>
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-2.6:
[SPARC64]: exec PT_DTRACE
[SPARC64]: Use shorter list_splice_init() for brevity.
[SPARC64]: Remove most limitations to kernel image size.
The PT_DTRACE flag is meaningless and obsolete.
Don't touch it.
Signed-off-by: Roland McGrath <roland@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently kernel images are limited to 8MB in size, and this causes
problems especially when enabling features that take up a lot of
kernel image space such as lockdep.
The code now will align the kernel image size up to 4MB and map that
many locked TLB entries. So, the only practical limitation is the
number of available locked TLB entries which is 16 on Cheetah and 64
on pre-Cheetah sparc64 cpus. Niagara cpus don't actually have hw
locked TLB entry support. Rather, the hypervisor transparently
provides support for "locked" TLB entries since it runs with physical
addressing and does the initial TLB miss processing.
Fully utilizing this change requires some help from SILO, a patch for
which will be submitted to the maintainer. Essentially, SILO will
only currently map up to 8MB for the kernel image and that needs to be
increased.
Note that neither this patch nor the SILO bits will help with network
booting. The openfirmware code will only map up to a certain amount
of kernel image during a network boot and there isn't much we can to
about that other than to implemented a layered network booting
facility. Solaris has this, and calls it "wanboot" and we may
implement something similar at some point.
Signed-off-by: David S. Miller <davem@davemloft.net>
Add CONFIG_HAVE_KRETPROBES to the arch/<arch>/Kconfig file for relevant
architectures with kprobes support. This facilitates easy handling of
in-kernel modules (like samples/kprobes/kretprobe_example.c) that depend on
kretprobes being present in the kernel.
Thanks to Sam Ravnborg for helping make the patch more lean.
Per Mathieu's suggestion, added CONFIG_KRETPROBES and fixed up dependencies.
Signed-off-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Acked-by: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
__FUNCTION__ is gcc-specific, use __func__
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Because of the new futex validation init handler, we have
to accept faults in init section text as well as the normal
kernel text.
Thanks to Tom Callaway for the bug report.
Signed-off-by: David S. Miller <davem@davemloft.net>
Some parts of the kernel now do things like do *_user() accesses while
set_fs(KERNEL_DS) that fault on purpose.
See, for example, the code added by changeset
a0c1e9073e ("futex: runtime enable pi
and robust functionality").
That trips up the ASI sanity checking we make in do_kernel_fault().
Just remove it for now. Maybe we can add it back later with an added
conditional which looks at the current get_fs() value.
Signed-off-by: David S. Miller <davem@davemloft.net>
Fix following warnings:
WARNING: vmlinux.o(.text+0x4f980): Section mismatch in reference from the function kernel_map_range() to the function .init.text:__alloc_bootmem()
WARNING: vmlinux.o(.text+0x4f9cc): Section mismatch in reference from the function kernel_map_range() to the function .init.text:__alloc_bootmem()
alloc_bootmem() is only used during early init and for any subsequent
call to kernel_map_range() the program logic avoid the call.
So annotate kernel_map_range() with __ref to tell modpost to
ignore the reference to a __init function.
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Fix following warnings:
WARNING: vmlinux.o(.text+0x4b258): Section mismatch in reference from the function dr_cpu_data() to the function .devinit.text:mdesc_fill_in_cpu_data()
WARNING: vmlinux.o(.text+0x4b290): Section mismatch in reference from the function dr_cpu_data() to the function .cpuinit.text:cpu_up()
mdesc_fill_in_cpu_data() is only used during early init and for
cpu hotplug so the __cpuinit annotation is the correct choice.
We have the call chain:
dr_cpu_data() => dr_cpu_configure() => mdesc_fill_in_cpu_data()
dr_cpu_data() is used only during early init and for cpu
hotplug. So annotating them all __cpuinit solves the
section mismatch and should be correct.
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
arch/sparc64/kernel/process.c:504:17: warning: symbol 'sparc_do_fork' was not declared. Should it be static?
arch/sparc64/kernel/process.c:655:5: warning: symbol 'dump_fpu' was not declared. Should it be static?
arch/sparc64/kernel/process.c:708:16: warning: symbol 'sparc_execve' was not declared. Should it be static?
Signed-off-by: David S. Miller <davem@davemloft.net>
arch/sparc64/kernel/process.c:219:6: warning: symbol '__show_regs' was not declared. Should it be static?
Signed-off-by: David S. Miller <davem@davemloft.net>
Noticed via sparse:
arch/sparc64/kernel/process.c:215:6: warning: symbol 'show_stackframe' was not declared. Should it be static?
arch/sparc64/kernel/process.c:243:6: warning: symbol 'show_stackframe32' was not declared. Should it be static?
It is totally unused.
Signed-off-by: David S. Miller <davem@davemloft.net>
arch/sparc64/kernel/process.c:123:6: warning: symbol 'machine_alt_power_off' was not declared. Should it be static?
Signed-off-by: David S. Miller <davem@davemloft.net>
And also it's helper function pci_is_controller(). Both
are unused.
I can't remove the equivalent from sparc32 yet as some
ancient bus probing code still uses that platform's version.
Signed-off-by: David S. Miller <davem@davemloft.net>
The idea of this thing is we could save/restore the firmware's
palette when breaking in and out of the firmware prompt.
Only one driver implemented this (atyfb) and it's value is
questionable. If you're just debugging you don't really
care that the characters end up being purple or whatever.
And we can provide better debugging and firmware command
facilities with minimal in-kernel console I/O drivers.
Signed-off-by: David S. Miller <davem@davemloft.net>
Matthew Wilcox