This is the meat of the series which prevents any dcache alias creation
by always keeping the U and K mapping of a page congruent.
If a mapping already exists, and other tries to access the page, prev
one is flushed to physical page (wback+inv)
Essentially flush_dcache_page()/copy_user_highpage() create K-mapping
of a page, but try to defer flushing, unless U-mapping exist.
When page is actually mapped to userspace, update_mmu_cache() flushes
the K-mapping (in certain cases this can be optimised out)
Additonally flush_cache_mm(), flush_cache_range(), flush_cache_page()
handle the puring of stale userspace mappings on exit/munmap...
flush_anon_page() handles the existing U-mapping for anon page before
kernel reads it via the GUP path.
Note that while not complete, this is enough to boot a simple
dynamically linked Busybox based rootfs
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
This preps the low level dcache flush helpers to take vaddr argument in
addition to the existing paddr to properly flush the VIPT dcache
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
If a board isn't using twl4030, then dtc will complain about the missing
phandle (which is in twl4030.dtsi). Move the phy declaration to the dts
files.
Signed-off-by: Jason Cooper <jason@lakedaemon.net>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Commit 6770b211 (ARM: OMAP2+: Export SoC information to userspace)
had some broken return value handling as noted by Russell King:
+ soc_dev = soc_device_register(soc_dev_attr);
+ if (IS_ERR_OR_NULL(soc_dev)) {
+ kfree(soc_dev_attr);
+ return;
+ }
+
+ parent = soc_device_to_device(soc_dev);
+ if (!IS_ERR_OR_NULL(parent))
+ device_create_file(parent, &omap_soc_attr);
This is nonsense. For the first, IS_ERR() is sufficient. For the second,
tell me what error checking is required in the return value of this
function:
struct device *soc_device_to_device(struct soc_device *soc_dev)
{
return &soc_dev->dev;
}
when you've already determined that the passed soc_dev is a valid pointer.
If you read the comments against the prototype:
/**
* soc_device_to_device - helper function to fetch struct device
* @soc: Previously registered SoC device container
*/
struct device *soc_device_to_device(struct soc_device *soc);
if "soc" is valid, it means the "previously registered SoC device container"
must have succeeded and that can only happen if the struct device has been
registered. Ergo, there will always be a valid struct device pointer for
any registered SoC device container. Therefore, if soc_device_register()
succeeds, then the return value from soc_device_to_device() will always be
valid and no error checking of it is required.
Simples. The rule as ever applies here: get to know the APIs your using
and don't fumble around in the dark hoping that you'll get this stuff
right.
Fix it as noted by Russell.
Reported-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Add new clockevent driver that uses the counter present on the MIPS
Global Interrupt Controller.
Signed-off-by: Raghu Gandham <Raghu.Gandham@imgtec.com>
Signed-off-by: Steven J. Hill <Steven.Hill@imgtec.com>
Reorganize some of the GIC clocksource driver code. Below is a list of
the various changes.
* No longer select CSRC_GIC by default for Malta platform.
* Limit choice for either the GIC or R4K clocksource, not both.
* Change location in Makefile.
* Created new 'gic_read_count' function in common 'irq-gic.c' file.
* Change 'git_hpt_read' function in 'csrc-gic.c' to use new function.
* Surround GIC specific code in Malta platform code with #ifdef's.
* Only initialize the GIC clocksource if it was selected. Original
code called it unconditionally if a GIC was found.
Signed-off-by: Steven J. Hill <Steven.Hill@imgtec.com>
Move the global variable 'gic_frequency' to be defined in the file
'arch/mips/kernel/irq-gic.c' instead of defining it individually
for each platform making use of the GIC. Also change the type to
be an unsigned integer instead of signed.
Signed-off-by: Steven J. Hill <Steven.Hill@imgtec.com>
Move the global variable 'gic_present' to be defined in the file
'arch/mips/kernel/irq-gic.c' instead of defining it individually
for each platform making use of the GIC. Also change the type to
be an unsigned integer instead of signed.
Signed-off-by: Steven J. Hill <Steven.Hill@imgtec.com>
Add logic needed to handle unaligned accesses in MIPS16e mode.
Signed-off-by: Steven J. Hill <Steven.Hill@imgtec.com>
Signed-off-by: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
Add structures for all the MIPS16e instructions. Also add the
enumerations for all the bit fields for opcodes, functions, etc.
Signed-off-by: Steven J. Hill <Steven.Hill@imgtec.com>
Optimise 'strnlen' to use microMIPS instructions and/or optimisations
for binary size reduction. When the microMIPS ISA is not being used,
the library function compiles to the original binary code.
Signed-off-by: Steven J. Hill <Steven.Hill@imgtec.com>
Optimise 'strlen' to use microMIPS instructions and/or optimisations
for binary size reduction. When the microMIPS ISA is not being used,
the library function compiles to the original binary code.
Signed-off-by: Steven J. Hill <Steven.Hill@imgtec.com>
Optimise 'strncpy' to use microMIPS instructions and/or optimisations
for binary size reduction. When the microMIPS ISA is not being used,
the library function compiles to the original binary code.
Signed-off-by: Steven J. Hill <Steven.Hill@imgtec.com>
Optimise 'memset' to use microMIPS instructions and/or optimisations
for binary size reduction. When the microMIPS ISA is not being used,
the library function compiles to the original binary code.
Signed-off-by: Steven J. Hill <Steven.Hill@imgtec.com>
This adds the option to build the Linux kernel using only the
microMIPS ISA. The resulting kernel binary is, at a minimum,
20% smaller than using the MIPS32R2 ISA.
Signed-off-by: Steven J. Hill <Steven.Hill@imgtec.com>
Partially revert commit e0c14a260d66ba35935600d6435940a566fe806b
and turn off LL/SC when building a pure microMIPS kernel. This is
a temporary fix until the cmpxchg assembly macro functions are
re-written to not use the HI/LO registers in address calculations.
Also add .insn in selected user access functions which would
otherwise produce ISA mode jump incompatibilities. This is also a
temporary fix.
Signed-off-by: Steven J. Hill <Steven.Hill@imgtec.com>
Add logic needed to handle unaligned accesses in microMIPS mode.
Signed-off-by: Steven J. Hill <Steven.Hill@imgtec.com>
Signed-off-by: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
Add logic needed to properly calculate exceptions for delay slots
when in microMIPS mode.
Signed-off-by: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
Signed-off-by: Steven J. Hill <Steven.Hill@imgtec.com>
All exceptions must be taken in microMIPS mode, never in classic
MIPS mode or the kernel falls apart. A few NOP instructions are
used to maintain the correct alignment of microMIPS versions of
the exception vectors.
Signed-off-by: Steven J. Hill <Steven.Hill@imgtec.com>
Add logic needed to do floating point emulation in microMIPS mode.
Signed-off-by: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
Signed-off-by: Steven J. Hill <Steven. Hill@imgtec.com>
The macros did not properly take into account the ISA that
the kernel was being compiled with. A classic MIPS kernel
will have the standard 'uasm_i_##op' macro functions with
'MM_uasm_i_##op' macro functions for the microMIPS version.
A pure microMIPS kernel will have the standard macros with
'CL_uasm_i_##op' macro functions for the classic version.
Signed-off-by: Steven J. Hill <Steven.Hill@imgtec.com>
Jump or branch target addresses have the first bit set. The
original mask did not take this into account and will cause
a field overflow warning for the target address when a jump
immediate instruction is built.
Signed-off-by: Steven J. Hill <Steven.Hill@imgtec.com>
Currently, the following instructions are translated:
- CACHE (indexed)
- CACHE (va based): translated to a SYNCI, overkill on D-CACHE operations,
but still much faster than a trap.
- mfc0/mtc0: the virtual COP0 registers for the guest are implemented as
2-D array.
[COP#][SEL] and this is mapped into the guest kernel address space @ VA 0x0.
mfc0/mtc0 operations are transformed to load/stores.
Signed-off-by: Sanjay Lal <sanjayl@kymasys.com>
Cc: kvm@vger.kernel.org
Cc: linux-mips@linux-mips.org
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
As ftrace_regex_write() reads the result of ftrace_process_regex()
which can sometimes return a positive number, only consider a
failure if the return is negative. Otherwise, it will skip possible
other registered probes and by returning a positive number that
wasn't read, it will confuse the user processes doing the writing.
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
register_ftrace_function_probe() returns the number of functions
it registered, which can be zero, it can also return a negative number
if something went wrong. But event_enable_func() only checks for
the case that it didn't register anything, it needs to also check
for the case that something went wrong and return that error code
as well.
Added some comments about the code as well, to make it more
understandable.
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Return 0 instead of the number of activated ftrace function probes if
event_enable_func succeeded and return an error code if it failed or
did not register any functions. But it currently returns the number
of registered functions and if it didn't register anything, it returns 0,
but that is considered success.
This also fixes the return value. As if it succeeds, it returns the
number of functions that were enabled, which is returned back to
the user in ftrace_regex_write (the write() return code). If only
one function is enabled, then the return code of the write is one,
and this can confuse the user program in thinking it only wrote 1
byte.
Link: http://lkml.kernel.org/r/20130509054413.30398.55650.stgit@mhiramat-M0-7522
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Tom Zanussi <tom.zanussi@intel.com>
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
[ Rewrote change log to reflect that this fixes two bugs - SR ]
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
I get the following warning on boot:
------------[ cut here ]------------
WARNING: at drivers/base/core.c:575 device_create_file+0x9a/0xa0()
Hardware name: -[8737R2A]-
Write permission without 'store'
...
</snip>
Drilling down, this is related to dynamic channel ce_count attribute
files sporting a S_IWUSR mode without a ->store() function. Looking
around, it appears that they aren't supposed to have a ->store()
function. So remove the bogus write permission to get rid of the
warning.
Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Cc: Mauro Carvalho Chehab <mchehab@redhat.com>
Cc: <stable@vger.kernel.org> # 3.[89]
[ shorten commit message ]
Signed-off-by: Borislav Petkov <bp@suse.de>
This is an almost-undocumented instruction available in 32-bit mode.
I say "almost" undocumented because AMD documents it in their opcode
maps just to say that it is unavailable in 64-bit mode (sections
"A.2.1 One-Byte Opcodes" and "B.3 Invalid and Reassigned Instructions
in 64-Bit Mode").
It is roughly equivalent to "sbb %al, %al" except it does not
set the flags. Use fastop to emulate it, but do not use the opcode
directly because it would fail if the host is 64-bit!
Reported-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
Cc: stable@vger.kernel.org # 3.9
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
This is used by SGABIOS, KVM breaks with emulate_invalid_guest_state=1.
It is just a MOV in disguise, with a funny source address.
Reported-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
Cc: stable@vger.kernel.org # 3.9
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
This is used by SGABIOS, KVM breaks with emulate_invalid_guest_state=1.
AAM needs the source operand to be unsigned; do the same in AAD as well
for consistency, even though it does not affect the result.
Reported-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
Cc: stable@vger.kernel.org # 3.9
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Nothing semantical
* simplify the alignement code by using & operation only
* rename variables clearly as paddr
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Microblaze requires to enable IRQ in cpu_idle loop.
It should be the part of this patch:
"microblaze: Use generic idle loop"
(sha1: e962bb9e9c)
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
vaddr used to index the cache was clipped from the wrong end, and thus
would potentially fail to flush the correct lines.
The problem was dorment for so long because up until the recent
optimizations it was only used for ptrace break-point only flushes.
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
With the patch to support MMUv3, the base address for the loaded
binary image has changed, and a fix was applied to the U-Boot image.
This fixes the RedBoot image.
Signed-off-by: Chris Zankel <chris@zankel.net>
IRQ handlers are expected to run with IRQs disabled.
See e.g. http://lwn.net/Articles/380931/ for a longer story.
This was overlooked in the commit
2d1c645 xtensa: dispatch medium-priority interrupts
Revert to old behavior and simplify interrupt entry and exit code.
Interrupt handler still honours IRQ priority.
do_notify_resume/schedule must be called with interrupts enabled, enable
interrupts if we return from user exception.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Chris Zankel <chris@zankel.net>
IRQs are disabled when PS.EXCM is set or PS.INTLEVEL is equal to or
higher than LOCKLEVEL.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Chris Zankel <chris@zankel.net>
Definition of CALLER_ADDR* through __builtin_return_address makes
compiler insert calls to __xtensa_libgcc_window_spill, which in turn
makes fast_syscall_spill_registers syscall that clobbers registers when
called from the kernel mode, leading to invalid opcode exceptions on
return to userspace.
Provide definition for CALLER_ADDR0 as MAKE_PC_FROM_RA(a0, a1) and in
case CONFIG_FRAME_POINTER is enabled extract CALLER_ADDR{1-3} from
stack.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Chris Zankel <chris@zankel.net>
