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Dave Martin 6323875db2 ARM: 6501/1: Thumb-2: Correct data alignment for CONFIG_THUMB2_KERNEL in mm/proc-v7.S 
Directives such as .long and .word do not magically cause the
assembler location counter to become aligned in gas.  As a result,
using these directives in code sections can result in misaligned
data words when building a Thumb-2 kernel (CONFIG_THUMB2_KERNEL).

This is a Bad Thing, since the ABI permits the compiler to assume
that fundamental types of word size or above are word- aligned when
accessing them from C.  If the data is not really word-aligned,
this can cause impaired performance and stray alignment faults in
some circumstances.

In general, the following rules should be applied when using data
word declaration directives inside code sections:

    * .quad and .double:
         .align 3

    * .long, .word, .single, .float:
         .align (or .align 2)

    * .short:
        No explicit alignment required, since Thumb-2
        instructions are always 2 or 4 bytes in size.
        immediately after an instruction.

In this specific case, we can achieve the desired alignment by
forcing a 32-bit branch instruction using the W() macro, since the
assembler location counter is already 32-bit aligned in this case.

Reviewed-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Dave Martin <dave.martin@linaro.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
 		2010-11-30 13:44:25 +00:00
..
Kconfig ARM: Improve the L2 cache performance when PL310 is used 2010-10-26 11:39:54 +05:30
Makefile ARM: Remove DISCONTIGMEM support 2010-07-16 10:57:35 +01:00
abort-ev4.S
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abort-ev4t.S
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abort-ev5t.S
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abort-ev5tj.S
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abort-ev6.S
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abort-ev7.S
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abort-lv4t.S
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abort-macro.S
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abort-nommu.S
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alignment.c ARM: 6401/1: plug a race in the alignment trap handler 2010-09-23 15:17:04 +01:00
cache-fa.S ARM: 6466/1: implement flush_icache_all for the rest of the CPUs 2010-10-28 13:54:28 +01:00
cache-feroceon-l2.c
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cache-l2x0.c ARM: l2x0: Optimise the range based operations 2010-10-26 11:40:05 +05:30
cache-tauros2.c
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cache-v3.S ARM: 6466/1: implement flush_icache_all for the rest of the CPUs 2010-10-28 13:54:28 +01:00
cache-v4.S ARM: 6466/1: implement flush_icache_all for the rest of the CPUs 2010-10-28 13:54:28 +01:00
cache-v4wb.S ARM: 6466/1: implement flush_icache_all for the rest of the CPUs 2010-10-28 13:54:28 +01:00
cache-v4wt.S ARM: 6466/1: implement flush_icache_all for the rest of the CPUs 2010-10-28 13:54:28 +01:00
cache-v6.S ARM: 6405/1: Handle __flush_icache_all for CONFIG_SMP_ON_UP 2010-10-04 20:23:36 +01:00
cache-v7.S ARM: 6405/1: Handle __flush_icache_all for CONFIG_SMP_ON_UP 2010-10-04 20:23:36 +01:00
cache-xsc3l2.c
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context.c
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copypage-fa.c
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copypage-feroceon.c ARM: 6164/1: Add kto and kfrom to input operands list. 2010-06-08 19:42:18 +01:00
copypage-v3.c
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copypage-v4mc.c ARM: 6379/1: Assume new page cache pages have dirty D-cache 2010-09-19 12:17:43 +01:00
copypage-v4wb.c ARM: 6164/1: Add kto and kfrom to input operands list. 2010-06-08 19:42:18 +01:00
copypage-v4wt.c ARM: 6164/1: Add kto and kfrom to input operands list. 2010-06-08 19:42:18 +01:00
copypage-v6.c ARM: 6379/1: Assume new page cache pages have dirty D-cache 2010-09-19 12:17:43 +01:00
copypage-xsc3.c ARM: 6164/1: Add kto and kfrom to input operands list. 2010-06-08 19:42:18 +01:00
copypage-xscale.c ARM: 6379/1: Assume new page cache pages have dirty D-cache 2010-09-19 12:17:43 +01:00
dma-mapping.c ARM: Fix DMA coherent allocator alignment 2010-11-07 16:10:15 +00:00
extable.c
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fault-armv.c ARM: 6464/2: fix spinlock recursion in adjust_pte() 2010-10-28 13:53:47 +01:00
fault.c ARM: 6355/1: hw-breakpoint: add mechanism for hooking into prefetch aborts 2010-09-08 10:04:59 +01:00
fault.h
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flush.c ARM: 6386/1: flush_ptrace_access: invalidate correct I-cache alias 2010-10-04 20:57:10 +01:00
highmem.c mm: fix race in kunmap_atomic() 2010-10-27 18:03:05 -07:00
init.c ARM: memblock: move meminfo into find_limits directly 2010-10-28 13:54:44 +01:00
iomap.c
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ioremap.c ARM: avoid annoying <4>'s in printk output 2010-11-23 22:27:55 +00:00
mm.h ARM: Convert platform reservations to use LMB rather than bootmem 2010-07-27 08:48:23 +01:00
mmap.c ARM: implement CONFIG_STRICT_DEVMEM by disabling access to RAM via /dev/mem 2010-10-01 22:31:34 -04:00
mmu.c ARM: memblock: setup lowmem mappings using memblock 2010-10-28 13:54:45 +01:00
nommu.c ARM: Convert platform reservations to use LMB rather than bootmem 2010-07-27 08:48:23 +01:00
pabort-legacy.S
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pabort-v6.S
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pabort-v7.S
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pgd.c mm: remove pte_*map_nested() 2010-10-26 16:52:08 -07:00
proc-arm6_7.S ARM: hotplug cpu: Keep processor information, startup code & __lookup_processor_type 2010-10-08 10:07:32 +01:00
proc-arm7tdmi.S ARM: hotplug cpu: Keep processor information, startup code & __lookup_processor_type 2010-10-08 10:07:32 +01:00
proc-arm9tdmi.S ARM: hotplug cpu: Keep processor information, startup code & __lookup_processor_type 2010-10-08 10:07:32 +01:00
proc-arm720.S ARM: hotplug cpu: Keep processor information, startup code & __lookup_processor_type 2010-10-08 10:07:32 +01:00
proc-arm740.S ARM: hotplug cpu: Keep processor information, startup code & __lookup_processor_type 2010-10-08 10:07:32 +01:00
proc-arm920.S ARM: 6466/1: implement flush_icache_all for the rest of the CPUs 2010-10-28 13:54:28 +01:00
proc-arm922.S ARM: 6466/1: implement flush_icache_all for the rest of the CPUs 2010-10-28 13:54:28 +01:00
proc-arm925.S ARM: 6466/1: implement flush_icache_all for the rest of the CPUs 2010-10-28 13:54:28 +01:00
proc-arm926.S ARM: 6466/1: implement flush_icache_all for the rest of the CPUs 2010-10-28 13:54:28 +01:00
proc-arm940.S ARM: 6466/1: implement flush_icache_all for the rest of the CPUs 2010-10-28 13:54:28 +01:00
proc-arm946.S ARM: 6466/1: implement flush_icache_all for the rest of the CPUs 2010-10-28 13:54:28 +01:00
proc-arm1020.S ARM: 6466/1: implement flush_icache_all for the rest of the CPUs 2010-10-28 13:54:28 +01:00
proc-arm1020e.S ARM: 6466/1: implement flush_icache_all for the rest of the CPUs 2010-10-28 13:54:28 +01:00
proc-arm1022.S ARM: 6466/1: implement flush_icache_all for the rest of the CPUs 2010-10-28 13:54:28 +01:00
proc-arm1026.S ARM: 6466/1: implement flush_icache_all for the rest of the CPUs 2010-10-28 13:54:28 +01:00
proc-fa526.S ARM: hotplug cpu: Keep processor information, startup code & __lookup_processor_type 2010-10-08 10:07:32 +01:00
proc-feroceon.S ARM: 6466/1: implement flush_icache_all for the rest of the CPUs 2010-10-28 13:54:28 +01:00
proc-macros.S
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proc-mohawk.S ARM: hotplug cpu: Keep processor information, startup code & __lookup_processor_type 2010-10-08 10:07:32 +01:00
proc-sa110.S ARM: hotplug cpu: Keep processor information, startup code & __lookup_processor_type 2010-10-08 10:07:32 +01:00
proc-sa1100.S ARM: hotplug cpu: Keep processor information, startup code & __lookup_processor_type 2010-10-08 10:07:32 +01:00
proc-syms.c
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proc-v6.S Merge branch 'hotplug' into devel 2010-10-18 22:34:47 +01:00
proc-v7.S ARM: 6501/1: Thumb-2: Correct data alignment for CONFIG_THUMB2_KERNEL in mm/proc-v7.S 2010-11-30 13:44:25 +00:00
proc-xsc3.S ARM: 6466/1: implement flush_icache_all for the rest of the CPUs 2010-10-28 13:54:28 +01:00
proc-xscale.S ARM: 6466/1: implement flush_icache_all for the rest of the CPUs 2010-10-28 13:54:28 +01:00
tlb-fa.S
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tlb-v3.S
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tlb-v4.S
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tlb-v4wb.S
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tlb-v4wbi.S
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tlb-v6.S
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tlb-v7.S ARM: Allow SMP kernels to boot on UP systems 2010-10-04 20:23:36 +01:00
vmregion.c ARM: DMA coherent allocator: align remapped addresses 2010-07-27 10:43:48 +01:00
vmregion.h ARM: DMA coherent allocator: align remapped addresses 2010-07-27 10:43:48 +01:00