Since uncompressed kernel image does not have to be bootable anymore,
move head.S, head_kdump.S and als.c to boot/ folder and compile them
in just in the decompressor.
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Dropping support for uncompressed kernel "image" build. Having
both image and bzImage makes it complicated to add new code to an
early boot phase (which is part of vmlinux for uncompressed kernel and
a separate arch/s390/boot/compressed/vmlinux for bzImage).
e.g. sclp_early_core.o is used for both, the decompressor phase and the
main kernel. The fact of having uncompressed kernel "image" forces us
to have a single object file and sacrifice instrumentation flags on such
files (so that we could use them early). The story gets much more
complicated with the need to utilize some of the string functions.
With bzImage only support, we have 2 separate boot stages each built
and linked separately, which allows to reuse some shared code, but
recompile with appropriate flags.
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The decompressor requires its own set of cc and asm flags, to avoid
building with features which do not make sense at such an early boot stage
(e.g. expoline, ftrace).
Currently cc flags are already set for the decompressor, but "cflags-y"
is not exported and hence empty. To fix that and to add asm flags, define
and export KBUILD_AFLAGS_DECOMPRESSOR and KBUILD_CFLAGS_DECOMPRESSOR
and rely on them in the decompressor's Makefile.
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
-mkernel-backchain cc flag is obsolete since quite a while, and not
present in minimal (supported by s390) gcc version 4.3. Removing it.
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
To avoid a mixture of asm code with expolines and c code without them,
propagate CC_USING_EXPOLINE to KBUILD_AFLAGS and use it to detect
whether asm code should have expolines or not.
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The kernel depends on macros like __BYTE_ORDER__,
__BIG_ENDIAN__ or __LITTLE_ENDIAN__.
OTOH, sparse doesn't know about the endianness of the kernel and
by default uses the same as the machine on which sparse was built.
Ensure that sparse can predefine the macros corresponding to
how the kernel was configured by adding -m{big,little}-endian
to CHECKFLAGS in the main Makefile (and so for all archs).
Also, remove the equivalent done in arch specific Makefiles.
Signed-off-by: Luc Van Oostenryck <luc.vanoostenryck@gmail.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Automatically decide between nobp vs. expolines if the spectre_v2=auto
kernel parameter is specified or CONFIG_EXPOLINE_AUTO=y is set.
The decision made at boot time due to CONFIG_EXPOLINE_AUTO=y being set
can be overruled with the nobp, nospec and spectre_v2 kernel parameters.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Even though s390 compressed kernel support has been introduced long ago,
by default uncompressed kernel image is used by packaging targets like:
"make rpm-pkg", "make deb-pkg" as well as "make image_name".
At the same time "make install" would use compressed bzImage by default.
To avoid ambiguity, set bzImage as default image for packaging.
Signed-off-by: Vasily Gorbik <gor@linux.vnet.ibm.com>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Add CONFIG_EXPOLINE to enable the use of the new -mindirect-branch= and
-mfunction_return= compiler options to create a kernel fortified against
the specte v2 attack.
With CONFIG_EXPOLINE=y all indirect branches will be issued with an
execute type instruction. For z10 or newer the EXRL instruction will
be used, for older machines the EX instruction. The typical indirect
call
basr %r14,%r1
is replaced with a PC relative call to a new thunk
brasl %r14,__s390x_indirect_jump_r1
The thunk contains the EXRL/EX instruction to the indirect branch
__s390x_indirect_jump_r1:
exrl 0,0f
j .
0: br %r1
The detour via the execute type instruction has a performance impact.
To get rid of the detour the new kernel parameter "nospectre_v2" and
"spectre_v2=[on,off,auto]" can be used. If the parameter is specified
the kernel and module code will be patched at runtime.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Previously, the generated dis.h and facilities.h header files have been
stored in include/generated. Because they are s390 specific, store them
in the arch/s390/include/generated/asm/ directory. Also update
references to the header files respectively.
To prevent name collisions with those header files in asm/ that
include the generated ones, rename the generated headers files
and add an -defs suffix. Also update the generators to create
the ifdef guards respectively.
Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Generate the system call specific files from the archheaders
and archprepare make targets.
Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Revise and add CFI CFA and register rule annotations to the vDSO
functions for proper stack unwinding and debugging.
Because glibc might call the vDSO in special ways, the vDSO code
does not rely on a stack frame created by the caller. The TOD clock
value can be therefore not stored in the pre-allocated stack area
and additional stack space is required.
To correctly annotate these situations with CFI, the .cfi_val_offset
directive is required to create relative offsets on the value of the
stack register %r15. Because the .cfi_val_offset directive is
available with recent GNU assembler versions only, additional checks
are necessary.
Note that if the vDSO is assembled with an older assembler version,
stack unwinding and debugging from within the vDSO code might not
be possible.
Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Using perf probe and libdw on kernel modules failed to find CFI
data for symbols. The CFI data is stored in the .eh_frame section.
The elfutils libdw is not able to extract the CFI data correctly,
because the .eh_frame section requires "non-simple" relocations
for kernel modules.
The suggestion is to avoid these "non-simple" relocations by emitting
the CFI data in the .debug_frame section. Let gcc emit respective
directives by specifying the -fno-asynchronous-unwind-tables option.
Using the .debug_frame section for CFI data, the .eh_frame section
becomes unused and, thus, discard it for kernel and modules builds
The vDSO requires the .eh_frame section and, hence, emit the CFI data
in both, the .eh_frame and .debug_frame sections.
See also discussion on elfutils/libdw bugzilla:
https://sourceware.org/bugzilla/show_bug.cgi?id=22452
Suggested-by: Mark Wielaard <mark@klomp.org>
Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Now that the SPDX tag is in all arch/s390/ files, that identifies the
license in a specific and legally-defined manner. So the extra GPL text
wording in the remaining files can be removed as it is no longer needed
at all.
This is done on a quest to remove the 700+ different ways that files in
the kernel describe the GPL license text. And there's unneeded stuff
like the address (sometimes incorrect) for the FSF which is never
needed.
No copyright headers or other non-license-description text was removed.
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
It's good to have SPDX identifiers in all files to make it easier to
audit the kernel tree for correct licenses.
Update the remaining arch/s390/ files with the correct SPDX license
identifier based on the license text in the file itself. The SPDX
identifier is a legally binding shorthand, which can be used instead of
the full boiler plate text.
This work is based on a script and data from Thomas Gleixner, Philippe
Ombredanne, and Kate Stewart.
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Cornelia Huck <cohuck@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Kate Stewart <kstewart@linuxfoundation.org>
Cc: Philippe Ombredanne <pombredanne@nexb.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The current way of adding new instructions to the opcode tables is
painful and error prone. Therefore add, similar to binutils, a text
file which contains all opcodes and the corresponding mnemonics and
instruction formats.
A small gen_opcode_table tool then generates a header file with the
required enums and opcode table initializers at the prepare step of
the kernel build.
This way only a simple text file has to be maintained, which can be
rather easily extended.
Unlike before where there were plenty of opcode tables and a large
switch statement to find the correct opcode table, there is now only
one opcode table left which contains all instructions. A second opcode
offset table now contains offsets within the opcode table to find
instructions which have the same opcode prefix. In order to save space
all 1-byte opcode instructions are grouped together at the end of the
opcode table. This is also quite similar to like it was before.
In addition also move and change code and definitions within the
disassembler. As a side effect this reduces the size required for the
code and opcode tables by ~1.5k.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
s390 is big-endian only but sparse assumes the same endianness
as the building machine.
This is problematic for code which expect __BYTE_ORDER__ being
correctly predefined by the compiler which sparse can then
pre-process differently from what gcc would, depending on the
building machine endianness.
Fix this by letting sparse know about the architecture endianness.
Signed-off-by: Luc Van Oostenryck <luc.vanoostenryck@gmail.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Add detection for machine type 0x3906 and set the ELF platform name
to z14. Add the miscellaneous-instruction-extension 2 facility to
the list of facilities for z14.
And allow to generate code that only runs on a z14 machine.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
With git commit 0eab11c7e0
"s390/vx: allow to include vx-insn.h with .include"
and an older gcc we get errors like this:
{standard input}:6: Error: can't open asm/vx-insn.h for reading:
No such file or directory
arch/s390/kernel/fpu.c:57: Error: Unrecognized opcode: `vstm'
To solve this issue simply add the path to arch/s390/include to
all assembler runs.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Modifying the architecture level set facility lists was always very
error prone. Given the numbering of the facility bits within the
Principles of Operation, where the most significant bit number is 0,
it happened a lot of times that wrong bits were set or cleared.
Therefore this patch adds a tool "gen_facilities" which generates
include/generated/facilites.h. The definition of the bits to be set
is contained within arch/s390/include/asm/facilities_src.h and can be
easily extended to e.g. also generate such lists for the KVM module.
The generated file looks like this:
#define FACILITIES_ALS _AC(0xc1006450f0040000,UL)
#define FACILITIES_ALS_DWORDS 1
The facility bits defined in this patch match 1:1 to the current masks
that can be found in head.S.
That is if the tool gets executed with -march=z990 then the generated
masks will equal the masks in head.S for CONFIG_MARCH_Z990.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The 31-bit assembler code for the early sclp console is error
prone as git commit fde24b54d976cc123506695c17db01438a11b673
"s390/sclp: clear upper register halves in _sclp_print_early"
has shown.
Convert the assembler code to C.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Remove the 31 bit support in order to reduce maintenance cost and
effectively remove dead code. Since a couple of years there is no
distribution left that comes with a 31 bit kernel.
The 31 bit kernel also has been broken since more than a year before
anybody noticed. In addition I added a removal warning to the kernel
shown at ipl for 5 minutes: a960062e58 ("s390: add 31 bit warning
message") which let everybody know about the plan to remove 31 bit
code. We didn't get any response.
Given that the last 31 bit only machine was introduced in 1999 let's
remove the code.
Anybody with 31 bit user space code can still use the compat mode.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Make use of gcc's hotpatch support to generate better code for ftrace
function tracing.
The generated code now contains only a six byte nop in each function
prologue instead of a 24 byte code block which will be runtime patched to
support function tracing.
With the new code generation the runtime overhead for supporting function
tracing is close to zero, while the original code did show a significant
performance impact.
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Currently the march flag gets only passed to C files, but not to
assembler files.
This means that we can't add new instructions like e.g. aghik to asm
files, since the assembler doesn't know of the new instructions if
the appropriate march flag isn't specified.
So also pass the march flag when compiling assembler files as well.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Add a new Kconfig choice group which allows to configure how gcc should
tune the generated code (via -mtune option).
By default the -mtune parameter will match the -march parameter.
This is a rather large patch, but I wouldn't know how to make this shorter
unfortunately.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Currently we only set the -march compiler option if the kbuild
system figured out that the compiler actually supports the selected
architecture (cc-option test).
In result this means that no -march compiler option is set when an
unsupported cpu architecture of the current compiler is selected.
The kernel compile will afterwards succeed but with the default
architecture instead of the (unsupported) selected one.
Change this behaviour, so compiles will fail if the compiler does
not support the selected cpu architecture.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
We've seen repeatedly that 8KB stack size on 64 bit kernels
is not sufficient.
So simply remove the config option.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The xfs module uses a lot of tracepoint, with TRACEPOINTS=y and a
few debugging options the GOT table of the xfs module will get
bigger than 4K. To get a working xfs module it needs to be compiled
with -fPIC instead of -fpic. To play safe use -fPIC for all modules.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Allow to generate code that only runs on zEC12 machines.
Also add a check which prevents the kernel to run on machines which
do not have any of the following new facilities installed:
- (48) decimal-floating-point zoned-conversion
- (49) execution-hint
- (49) load-and-trap
- (49) miscellaneous-instruction-extensions
- (49) processor-assist
- (50) constrained transactional-execution
- (73) transactional-execution
48, 49, 50 and 73 are the bit numbers of the facility indications for
each of the required facilities.
Note that we assume that user-space gets compiled with the same
compiler options, therefore we also test for a dfp facility even
if the kernel doesn't make use of it.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.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
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>
Only add subdirectories of arch/s390 to kbuild if their respective
config option is selected.
Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Newer gcc versions offer an architecture-independent option to check
the stack size and warn if it reaches a certain limit. This option
already existed for s390 by using -mwarn-dynamicstack. Since one
stack check option is enough remove the s390 specific stack check
but keep the option that warns about dynamic stack usage because
that is not covered by the generic option.
Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Add a kernel config option for the IBM zEnterprise 196. This will
produce faster code on newer compilers using the -march=z196 option.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Introducing this Kbuild file allow us to:
make arch/s390/
And thus building all the core part of s390.
Same as on other architectures.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
It is now possible to assign options to AS, CC and LD
on the command line - which is only used when building modules.
{A,C,LD}FLAGS_MODULE was all used both in the top-level Makefile
in the arch makefiles, thus users had no way to specify
additional options to AS, CC, LD when building modules
without overriding the original value.
Introduce a new set of variables KBUILD_{A,C,LD}FLAGS_MODULE
that is used by arch specific files and free up
{A,C,LD}FLAGS_MODULE so they can be assigned on
the command line.
All arch Makefiles that used the old variables has been updated.
Note: Previously we had a MODFLAGS variable for both
AS and CC. But in favour of consistency this was dropped.
So in some cases arch Makefile has one assignmnet replaced by
two assignmnets.
Note2: MODFLAGS was not documented and is dropped
without any notice. I do not expect much/any breakage
from this.
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Cc: Denys Vlasenko <vda.linux@googlemail.com>
Cc: Haavard Skinnemoen <hskinnemoen@atmel.com>
Cc: Mike Frysinger <vapier@gentoo.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Chen Liqin <liqin.chen@sunplusct.com>
Acked-by: Mike Frysinger <vapier@gentoo.org> [blackfin]
Acked-by: Haavard Skinnemoen <haavard.skinnemoen@atmel.com> [avr32]
Signed-off-by: Michal Marek <mmarek@suse.cz>
Add missing vdso_install target to install the unstripped vdso images
into $(MODLIB)/vdso/. These files are helpful when containing
additional debugging information.
Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Add the "bzImage" compile target and the necessary code to generate
compressed kernel images. The old style uncompressed "image" target
is preserved, a simple make will build them both.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Merge the nearly empty C files and move everything from power/ to
kernel/. That way the files are easier to handle.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
This patch introduces the hibernation backend support to the
s390 architecture. Now it is possible to suspend a mainframe Linux
guest using the following command:
echo disk > /sys/power/state
Signed-off-by: Hans-Joachim Picht <hans@linux.vnet.ibm.com>
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>
This patch contains the port of Qumranet's kvm kernel module to IBM zSeries
(aka s390x, mainframe) architecture. It uses the mainframe's virtualization
instruction SIE to run virtual machines with up to 64 virtual CPUs each.
This port is only usable on 64bit host kernels, and can only run 64bit guest
kernels. However, running 31bit applications in guest userspace is possible.
The following source files are introduced by this patch
arch/s390/kvm/kvm-s390.c similar to arch/x86/kvm/x86.c, this implements all
arch callbacks for kvm. __vcpu_run calls back into
sie64a to enter the guest machine context
arch/s390/kvm/sie64a.S assembler function sie64a, which enters guest
context via SIE, and switches world before and after that
include/asm-s390/kvm_host.h contains all vital data structures needed to run
virtual machines on the mainframe
include/asm-s390/kvm.h defines kvm_regs and friends for user access to
guest register content
arch/s390/kvm/gaccess.h functions similar to uaccess to access guest memory
arch/s390/kvm/kvm-s390.h header file for kvm-s390 internals, extended by
later patches
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Carsten Otte <cotte@de.ibm.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
The variable AFLAGS is a wellknown variable and the usage by
kbuild may result in unexpected behaviour.
On top of that several people over time has asked for a way to
pass in additional flags to gcc.
This patch replace use of AFLAGS with KBUILD_AFLAGS all over
the tree.
Patch was tested on following architectures:
alpha, arm, i386, x86_64, mips, sparc, sparc64, ia64, m68k, s390
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
The variable CFLAGS is a wellknown variable and the usage by
kbuild may result in unexpected behaviour.
On top of that several people over time has asked for a way to
pass in additional flags to gcc.
This patch replace use of CFLAGS with KBUILD_CFLAGS all over the
tree and enabling one to use:
make CFLAGS=...
to specify additional gcc commandline options.
One usecase is when trying to find gcc bugs but other
use cases has been requested too.
Patch was tested on following architectures:
alpha, arm, i386, x86_64, mips, sparc, sparc64, ia64, m68k
Test was simple to do a defconfig build, apply the patch and check
that nothing got rebuild.
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
s390 is the only 32bit with unsigned long for size_t (usual for those
is unsigned int). Tell sparse...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
s390 machines provide hardware support for creating Linux dumps on SCSI
disks. For creating a dump a special purpose dump Linux is used. The first
32 MB of memory are saved by the hardware before the dump Linux is
booted. Via an SCLP interface, the saved memory can be accessed from
Linux. This patch exports memory and registers of the crashed Linux to
userspace via a debugfs file. For more information refer to
Documentation/s390/zfcpdump.txt, which is included in this patch.
Signed-off-by: Michael Holzheu <holzheu@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Recent cvs versions of gcc have support for an improved stack overflow
checking that calculates the size of the guard size for each function.
If the compiler accepts -mstack-size without -mstack-guard then the
new stack check is available. We always want to use the new stack
checker.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
