Commit Graph

129 Commits

Author SHA1 Message Date
Linus Torvalds
1b05018045 Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus
Pull MIPS fixes from Ralf Baechle:
 "MIPS fixes for 3.11.  Half of then is for Netlogic the remainder
  touches things across arch/mips.

  Nothing really dramatic and by rc1 standards MIPS will be in fairly
  good shape with this applied.  Tested by building all MIPS defconfigs
  of which with this pull request four platforms won't build.  And yes,
  it boots also on my favorite test systems"

* 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus:
  MIPS: kvm: Kconfig: Drop HAVE_KVM dependency from VIRTUALIZATION
  MIPS: Octeon: Fix DT pruning bug with pip ports
  MIPS: KVM: Mark KVM_GUEST (T&E KVM) as BROKEN_ON_SMP
  MIPS: tlbex: fix broken build in v3.11-rc1
  MIPS: Netlogic: Add XLP PIC irqdomain
  MIPS: Netlogic: Fix USB block's coherent DMA mask
  MIPS: tlbex: Fix typo in r3000 tlb store handler
  MIPS: BMIPS: Fix thinko to release slave TP from reset
  MIPS: Delete dead invocation of exception_exit().
2013-07-19 15:10:01 -07:00
Aaro Koskinen
38a997a70e MIPS: tlbex: fix broken build in v3.11-rc1
Commit 6ba045f9fb (MIPS: Move generated code
to .text for microMIPS) deleted tlbmiss_handler_setup_pgd_array, but some
references were not converted. Fix that to enable building a MIPS kernel.

Signed-off-by: Aaro Koskinen <aaro.koskinen@iki.fi>
Acked-by: Jayachandran C. <jchandra@broadcom.com>
Acked-by: David Daney <david.daney@cavium.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/5589/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2013-07-19 10:36:10 +02:00
Tony Wu
afc813ae6d MIPS: tlbex: Fix typo in r3000 tlb store handler
commit 6ba045f (MIPS: Move generated code to .text for microMIPS)
causes a panic at boot. The handler builder should test against
handle_tlbs_end, not handle_tlbs.

Signed-off-by: Tony Wu <tung7970@gmail.com>
Acked-by: Jayachandran C. <jchandra@broadcom.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/5600/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2013-07-19 10:18:07 +02:00
Paul Gortmaker
078a55fc82 MIPS: Delete __cpuinit/__CPUINIT usage from MIPS code
commit 3747069b25e419f6b51395f48127e9812abc3596 upstream.

The __cpuinit type of throwaway sections might have made sense
some time ago when RAM was more constrained, but now the savings
do not offset the cost and complications.  For example, the fix in
commit 5e427ec2d0 ("x86: Fix bit corruption at CPU resume time")
is a good example of the nasty type of bugs that can be created
with improper use of the various __init prefixes.

After a discussion on LKML[1] it was decided that cpuinit should go
the way of devinit and be phased out.  Once all the users are gone,
we can then finally remove the macros themselves from linux/init.h.

Note that some harmless section mismatch warnings may result, since
notify_cpu_starting() and cpu_up() are arch independent (kernel/cpu.c)
and are flagged as __cpuinit  -- so if we remove the __cpuinit from
the arch specific callers, we will also get section mismatch warnings.
As an intermediate step, we intend to turn the linux/init.h cpuinit
related content into no-ops as early as possible, since that will get
rid of these warnings.  In any case, they are temporary and harmless.

Here, we remove all the MIPS __cpuinit from C code and __CPUINIT
from asm files.  MIPS is interesting in this respect, because there
are also uasm users hiding behind their own renamed versions of the
__cpuinit macros.

[1] https://lkml.org/lkml/2013/5/20/589

[ralf@linux-mips.org: Folded in Paul's followup fix.]

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/5494/
Patchwork: https://patchwork.linux-mips.org/patch/5495/
Patchwork: https://patchwork.linux-mips.org/patch/5509/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2013-07-14 19:36:51 -04:00
Ralf Baechle
6ac5310e64 Merge branch '3.10-fixes' into mips-for-linux-next
This that should have been fixed but weren't, way to much, intrusive
and late.
2013-07-12 18:11:43 +02:00
Tony Wu
42a111797e MIPS: Fix typos and cleanup comment
Signed-off-by: Tony Wu <tung7970@gmail.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/5535/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2013-07-01 15:10:57 +02:00
Jayachandran C
6ba045f9fb MIPS: Move generated code to .text for microMIPS
Prepare of a next patch which will call tlbmiss_handler_setup_pgd on
microMIPS. MicroMIPS complains if the called code s not in the .text
section. To fix this we generate code into space reserved in
arch/mips/mm/tlb-funcs.S

While there, move the rest of the generated functions (handle_tlbl,
handle_tlbs, handle_tlbm) to the same file.

Signed-off-by: Jayachandran C <jchandra@broadcom.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/5542/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2013-07-01 15:10:56 +02:00
Ralf Baechle
3f90b82df1 MIPS: tlbex: Fix size of area to be flushed.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2013-06-27 02:04:25 +02:00
Jonas Gorski
a3d9086bb1 MIPS: Flush TLB handlers directly after writing them
When having enabled MIPS_PGD_C0_CONTEXT, trap_init() might call the
generated tlbmiss_handler_setup_pgd before it was committed to memory,
causing boot failures:

  trap_init()
   |- per_cpu_trap_init()
   |   |- TLBMISS_HANDLER_SETUP()
   |       |- tlbmiss_handler_setup_pgd()
   |- flush_tlb_handlers()

To avoid this, move flush_tlb_handlers() into build_tlb_refill_handler()
right after they were generated. We can do this as the cache handling is
initialized just before creating the tlb handlers.

This issue was introduced in 3d8bfdd030
("MIPS: Use C0_KScratch (if present) to hold PGD pointer.").

Signed-off-by: Jonas Gorski <jogo@openwrt.org>
Cc: linux-mips@linux-mips.org
Cc: Steven J. Hill <Steven.Hill@imgtec.com>
Cc: Jayachandran C <jchandra@broadcom.com>
Cc: David Daney <david.daney@cavium.com>
Patchwork: https://patchwork.linux-mips.org/patch/5539/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2013-06-25 17:48:06 +02:00
Ralf Baechle
73acc7df53 MIPS: Fix TLBR-use hazards for R2 cores in the TLB reload handlers
MIPS R2 documents state that an execution hazard barrier is needed
after a TLBR before reading EntryLo.

Original patch by Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Patchwork: https://patchwork.linux-mips.org/patch/5526/
2013-06-21 18:07:03 +02:00
Jayachandran C
0e6ecc1a9a MIPS: Fixup check for invalid scratch register
The invalid value for scratch register is -1, so update the checks of
the form (scratch_reg > 0) to be (scratch_reg >= 0).  This will fix
the case in Netlogic XLP where the scratch_reg can be 0.

Signed-off-by: Jayachandran C <jchandra@broadcom.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/5444/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2013-06-13 17:46:43 +02:00
Jayachandran C
7777b9395b MIPS: Allow platform specific scratch registers
XLR/XLP COP0 scratch is register 22, sel 0-7. Add a function
c0_kscratch() which returns the scratch register for the platform,
and use the return value while generating TLB handlers.

Setup kscratch_mask to 0xf for XLR/XLP since the config4 register
does not exist. This allows the kernel to allocate scratch registers
0-3 if needed.

Signed-off-by: Jayachandran C <jchandra@broadcom.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/5445/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2013-06-13 17:46:43 +02:00
David Daney
be8a6d452b MIPS: Remove duplicate definition of check_for_high_segbits.
In C, one definition is sufficient.

Signed-off-by: David Daney <david.daney@cavium.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/5304/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2013-05-23 10:19:04 +02:00
David Daney
48c4ac976a Revert "MIPS: Allow ASID size to be determined at boot time."
This reverts commit d532f3d267.

The original commit has several problems:

1) Doesn't work with 64-bit kernels.

2) Calls TLBMISS_HANDLER_SETUP() before the code is generated.

3) Calls TLBMISS_HANDLER_SETUP() twice in per_cpu_trap_init() when
   only one call is needed.

[ralf@linux-mips.org: Also revert the bits of the ASID patch which were
hidden in the KVM merge.]

Signed-off-by: David Daney <david.daney@cavium.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Cc: "Steven J. Hill" <Steven.Hill@imgtec.com>
Cc: David Daney <david.daney@cavium.com>
Patchwork: https://patchwork.linux-mips.org/patch/5242/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2013-05-16 20:35:42 +02:00
David Daney
8ea6cd7af1 Revert "MIPS: microMIPS: Support dynamic ASID sizing."
This reverts commit f6b06d9361.

The next revert depends on this one, so this has to go too.

Signed-off-by: David Daney <david.daney@cavium.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Cc: "Steven J. Hill" <Steven.Hill@imgtec.com>
Cc: David Daney <david.daney@cavium.com>
Patchwork: https://patchwork.linux-mips.org/patch/5241/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2013-05-16 20:34:55 +02:00
Ralf Baechle
b22d1b6a91 Merge branch 'mti-next' of git://git.linux-mips.org/pub/scm/sjhill/linux-sjhill into mips-for-linux-next 2013-05-09 17:57:30 +02:00
Steven J. Hill
2a0b24f56c MIPS: microMIPS: Add support for exception handling.
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>
2013-05-09 17:55:18 +02:00
Steven J. Hill
f6b06d9361 MIPS: microMIPS: Support dynamic ASID sizing.
Changes for pure microMIPS cores to dynamically determine the ASID
size at boot time.

Includes bug fix https://patchwork.linux-mips.org/patch/5230/

Signed-off-by: Steven J. Hill <Steven.Hill@imgtec.com>
Signed-off-by: Jonas Gorski <jogo@openwrt.org>
2013-05-08 12:30:10 +02:00
Steven J. Hill
d532f3d267 MIPS: Allow ASID size to be determined at boot time.
Original patch by Ralf Baechle and removed by Harold Koerfgen
with commit f67e4ffc79905482c3b9b8c8dd65197bac7eb508. This
allows for more generic kernels since the size of the ASID
and corresponding masks can be determined at run-time. This
patch is also required for the new Aptiv cores and has been
tested on Malta and Malta Aptiv platforms.

[ralf@linux-mips.org: Added relevant part of fix
https://patchwork.linux-mips.org/patch/5213/]

Signed-off-by: Steven J. Hill <Steven.Hill@imgtec.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2013-05-08 12:30:10 +02:00
Ralf Baechle
9b3539e0e5 Merge branch 'mips-next-3.10' of git://git.linux-mips.org/pub/scm/john/linux-john into mips-for-linux-next 2013-05-08 01:27:46 +02:00
Huacai Chen
8759934e2b MIPS: Build uasm-generated code only once to avoid CPU Hotplug problem
This and the next patch resolve memory corruption problems while CPU
hotplug. Without these patches, memory corruption can triggered easily
as below:

On a quad-core MIPS platform, use "spawn" of UnixBench-5.1.3 (http://
code.google.com/p/byte-unixbench/) and a CPU hotplug script like this
(hotplug.sh):
while true; do
echo 0 >/sys/devices/system/cpu/cpu1/online
echo 0 >/sys/devices/system/cpu/cpu2/online
echo 0 >/sys/devices/system/cpu/cpu3/online
sleep 1
echo 1 >/sys/devices/system/cpu/cpu1/online
echo 1 >/sys/devices/system/cpu/cpu2/online
echo 1 >/sys/devices/system/cpu/cpu3/online
sleep 1
done

Run "hotplug.sh" and then run "spawn 10000", spawn will get segfault
after a few minutes.

This patch:
Currently, clear_page()/copy_page() are generated by Micro-assembler
dynamically. But they are unavailable until uasm_resolve_relocs() has
finished because jump labels are illegal before that. Since these
functions are shared by every CPU, we only call build_clear_page()/
build_copy_page() only once at boot time. Without this patch, programs
will get random memory corruption (segmentation fault, bus error, etc.)
while CPU Hotplug (e.g. one CPU is using clear_page() while another is
generating it in cpu_cache_init()).

For similar reasons we modify build_tlb_refill_handler()'s invocation.

V2:
1, Rework the code to make CPU#0 can be online/offline.
2, Introduce cpu_has_local_ebase feature since some types of MIPS CPU
   need a per-CPU tlb_refill_handler().

Signed-off-by: Huacai Chen <chenhc@lemote.com>
Signed-off-by: Hongbing Hu <huhb@lemote.com>
Acked-by: David Daney <david.daney@cavium.com>
Patchwork: http://patchwork.linux-mips.org/patch/4994/
Acked-by: John Crispin <blogic@openwrt.org>
2013-05-08 01:19:06 +02:00
Ralf Baechle
0bfbf6a256 MIPS: Make declarations and definitions of tlbmiss_handler_setup_pgd match.
tlbmiss_handler_setup_pgd is run-time generated code and it was convenient
to pretend the symbol was an array in the generator but a function for
the users.  LTO gcc won't tolerate this kind of lie anymore so solve the
problem through a cast and function pointer instead.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2013-04-11 13:04:11 +02:00
Ralf Baechle
8bfc245f9a Merge branch 'mips-next-3.9' of git://git.linux-mips.org/pub/scm/john/linux-john into mips-for-linux-next 2013-02-21 12:51:33 +01:00
Steven J. Hill
f8fa4811db MIPS: Add support for the M14KEc core.
Signed-off-by: Steven J. Hill <sjhill@mips.com>
Patchwork: http://patchwork.linux-mips.org/patch/4682/
Signed-off-by: John Crispin <blogic@openwrt.org>
2013-02-17 00:15:23 +01:00
Ralf Baechle
7034228792 MIPS: Whitespace cleanup.
Having received another series of whitespace patches I decided to do this
once and for all rather than dealing with this kind of patches trickling
in forever.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2013-02-01 10:00:22 +01:00
Ralf Baechle
9120963578 Revert "MIPS: Optimise TLB handlers for MIPS32/64 R2 cores."
This reverts commit ff401e5210.

This breaks on MIPS64 R2 cores such as Broadcom's.
2012-12-27 16:27:35 +01:00
Ralf Baechle
241738bd51 Merge branch 'mips-next' of http://dev.phrozen.org/githttp/mips-next into mips-for-linux-next 2012-12-13 19:40:13 +01:00
Ralf Baechle
bdf20507da MIPS: PMC-Sierra Yosemite: Remove support.
Nobody seems to be interested anymore and upstream also never had an
ethernet driver.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2012-12-13 18:15:30 +01:00
Ralf Baechle
970d032fec MIPS: Transparent Huge Pages support
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2012-12-12 16:48:52 +01:00
David Daney
aa1762f49c MIPS: Control huge tlb support via Kconfig symbol MIPS_HUGE_TLB_SUPPORT
We need Huge TLBs for HUGETLB_PAGE, or the soon to follow
TRANSPARENT_HUGEPAGE.  collect this information under a single Kconfig
symbol.

Signed-off-by: David Daney <david.daney@cavium.com>
2012-12-12 16:48:47 +01:00
Ralf Baechle
a2c763e074 MIPS: tlbex: Better debug output.
Pgtable bits are assigned dynamically depending on processor feature and
statically based on kernel configuration.  To make sense out of the
disassembled TLB exception handlers a list of the actual assignments
used for a particular configuration and hardware setup can be very useful.

Output the actual TLB exception handlers in a format that simplifies their
post processsing from dmesg output.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2012-11-26 13:41:06 +01:00
Ralf Baechle
fb2b1dbadf MIPS: Remove R5000A.
From a software perspective R5000 and R5000A are the same thing which is
why the symbol CPU_R5000A never got used, so finally delete it.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2012-11-26 13:41:05 +01:00
Kevin Cernekee
f151f3b92b MIPS: tlbex: Fix section mismatches
The new functions introduced in commit 02a5417751 (MIPS: tlbex: Deal with
re-definition of label) should be marked __cpuinit, to eliminate a
warning that can pop up when CONFIG_EXPORT_UASM is disabled:

      LD      arch/mips/mm/built-in.o
    WARNING: arch/mips/mm/built-in.o(.text+0x2a4c): Section mismatch in reference from the function uasm_bgezl_hazard() to the function .cpuinit.text:uasm_il_bgezl()
    The function uasm_bgezl_hazard() references
    the function __cpuinit uasm_il_bgezl().
    This is often because uasm_bgezl_hazard lacks a __cpuinit
    annotation or the annotation of uasm_il_bgezl is wrong.

    WARNING: arch/mips/mm/built-in.o(.text+0x2a68): Section mismatch in reference from the function uasm_bgezl_label() to the function .cpuinit.text:uasm_build_label()
    The function uasm_bgezl_label() references
    the function __cpuinit uasm_build_label().
    This is often because uasm_bgezl_label lacks a __cpuinit
    annotation or the annotation of uasm_build_label is wrong.

(This warning might not occur if the function was inlined.)

Signed-off-by: Kevin Cernekee <cernekee@gmail.com>
Patchwork: http://patchwork.linux-mips.org/patch/4517
Signed-off-by: John Crispin <blogic@openwrt.org>
2012-11-09 11:37:16 +01:00
Ralf Baechle
359187d647 MIPS: R5000: Fix TLB hazard handling.
R5000 and the Nevada CPUs (RM5230, RM5231, RM5260, RM5261, RM5270 and
RM5271) are basically the same CPU core and all are documented to require
two instructions separating a write to c0_pagemask, c0_entryhi, c0_entrylo0,
c0_entrylo1 or c0_index.

So far we were only providing on cycle before / after a TLBR/TLBWI
for R5000 but 3 cycles before and 1 cycles after for the Nevadas.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2012-10-16 22:22:23 +02:00
Ralf Baechle
02a5417751 MIPS: tlbex: Deal with re-definition of label
The microassembler used in tlbex.c does not notice if a label is redefined
resulting in relocations against such labels silently missrelocated.
The issues exists since commit add6eb04776db4189ea89f596cbcde31b899be9d
[Synthesize TLB exception handlers at runtime.] in 2.6.10 and went unnoticed
for so long because the relocations for the affected branches got computed
to do something *almost* sensible.

The issue affects R4000, R4400, QED/IDT RM5230, RM5231, RM5260, RM5261,
RM5270 and RM5271 processors.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2012-10-16 22:21:27 +02:00
David Daney
748e787eb6 MIPS: Optimize TLB refill for RI/XI configurations.
We don't have to do a separate shift to eliminate the software bits,
just rotate them into the fill and they will be ignored.

Signed-off-by: David Daney <ddaney@caviumnetworks.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/4294/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2012-10-11 11:11:20 +02:00
Ralf Baechle
cb418b34ca Merge branch 'ralf-3.7' of git://git.linux-mips.org/pub/scm/sjhill/linux-sjhill into mips-for-linux-next 2012-09-28 16:29:55 +02:00
Steven J. Hill
05857c64ec MIPS: Replace 'kernel_uses_smartmips_rixi' with 'cpu_has_rixi'.
Remove usage of the 'kernel_uses_smartmips_rixi' macro from all files
and use new 'cpu_has_rixi' instead.

Signed-off-by: Steven J. Hill <sjhill@mips.com>
Acked-by: David Daney <david.daney@cavium.com>
2012-09-13 17:00:34 -05:00
Steven J. Hill
ff401e5210 MIPS: Optimise TLB handlers for MIPS32/64 R2 cores.
The EXT and INS instructions can be used to decrease code size and
thus speed up TLB handlers on MIPS32R2 and MIPS64R2 cores.

Signed-off-by: Steven J. Hill <sjhill@mips.com>
2012-09-13 15:43:54 -05:00
Steven J. Hill
625c0a2170 MIPS: Avoid pipeline stalls on some MIPS32R2 cores.
The architecture specification says that an EHB instruction is
needed to avoid a hazard when writing TLB entries. However, some
cores do not have this hazard, and thus the EHB instruction causes
a costly pipeline stall. Detect these cores and do not use the EHB
instruction.

Signed-off-by: Steven J. Hill <sjhill@mips.com>
2012-09-13 15:43:52 -05:00
Steven J. Hill
113c62d984 MIPS: Add support for the M14Kc core.
[ralf@linux-mips.org: Fixed whitespace damage.]

Signed-off-by: Steven J. Hill <sjhill@mips.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/3773/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2012-07-06 23:56:00 +02:00
David Howells
b81947c646 Disintegrate asm/system.h for MIPS
Disintegrate asm/system.h for MIPS.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Ralf Baechle <ralf@linux-mips.org>
cc: linux-mips@linux-mips.org
2012-03-28 18:30:02 +01:00
David Daney
0f4ccbc835 MIPS: No branches in delay slots for huge pages in handle_tlbl
For the case PM_DEFAULT_MASK == 0, we were placing a branch in the
delay slot of another branch.  This leads to undefined behavior.

Signed-off-by: David Daney <david.daney@cavium.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/2775/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2011-09-21 17:54:07 +02:00
Ralf Baechle
d954ffe34a MIPS: tlbex: Fix build error in R3000 code.
Only some GCC versions such as gcc 4.2 notice that the variable wr in
build_r3000_tlb_modify_handler is used uninitialized.  When using one
of those GCCs the build will fail due to -Werror.  GCC 4.6 does not
warn about the uninitialized use of wr.

This issue was introduced by 7211f4d7a3dcbe57c5d396c334dca525315dceb2
[MIPS: Close races in TLB modify handlers.]

Reported-by: Ganesan Ramalingam <ganesan18@gmail.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2011-09-21 17:53:07 +02:00
David Daney
bf28607fbe MIPS: Close races in TLB modify handlers.
Page table entries are made invalid by writing a zero into the the PTE
slot in a page table.  This creates a race condition with the TLB
modify handlers when they are updating the PTE.

CPU0                              CPU1

Test for _PAGE_PRESENT
.                                 set to not _PAGE_PRESENT (zero)
Set to _PAGE_VALID

So now the page not present value (zero) is suddenly valid and user
space programs have access to physical page zero.

We close the race by putting the test for _PAGE_PRESENT and setting of
_PAGE_VALID into an atomic LL/SC section.  This requires more registers
than just K0 and K1 in the handlers, so we need to save some registers
to a save area and then restore them when we are done.

The save area is an array of cacheline aligned structures that should
not suffer cache line bouncing as they are CPU private.

[ralf@linux-mips.org: Fix !defined(CONFIG_MIPS_PGD_C0_CONTEXT) build error.]

Signed-off-by: David Daney <david.daney@cavium.com>
To: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/2577/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2011-07-26 06:47:47 +01:00
Jayachandran C
efa0f81c11 MIPS: Netlogic: Cache, TLB support and feature overrides for XLR
CPU_XLR case added to mm/tlbex.c
CPU_XLR case added to mm/c-r4k.c for PINDEX attribute
Feature overrides for XLR cpu.

Signed-off-by: Jayachandran C <jayachandranc@netlogicmicro.com>
To: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/2333/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2011-05-19 09:55:40 +01:00
Ralf Baechle
4a9040f451 MIPS: tlbex: Fix GCC 4.6.0 build error
CC      arch/mips/mm/tlbex.o
arch/mips/mm/tlbex.c: In function 'build_r4000_tlb_refill_handler':
arch/mips/mm/tlbex.c:1155:22: error: variable 'vmalloc_mode' set but not used [-Werror=unused-but-set-variable]
arch/mips/mm/tlbex.c:1154:28: error: variable 'htlb_info' set but not used [-Werror=unused-but-set-variable]
cc1: all warnings being treated as errors

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2011-05-10 18:15:22 +01:00
Lucas De Marchi
25985edced Fix common misspellings
Fixes generated by 'codespell' and manually reviewed.

Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>
2011-03-31 11:26:23 -03:00
David Daney
e1c87d2a55 MIPS: Add an unreachable return statement to satisfy buggy GCCs.
It was reported that GCC-4.3.3 (with CodeSourcery extensions) fails
without this.

Reported-by: Jonas Gorski <jonas.gorski@gmail.com>
Signed-off-by: David Daney <ddaney@caviumnetworks.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/2010/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2011-03-14 21:07:24 +01:00
David Daney
2c8c53e28f MIPS: Optimize TLB handlers for Octeon CPUs
Octeon can use scratch registers in the TLB handlers.  Octeon II can
use LDX instructions.

Signed-off-by: David Daney <ddaney@caviumnetworks.com>
To: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/1904/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2011-01-18 19:30:23 +01:00