[PATCH v5 05/16] ARM: use a function table for determining instruction interpreter action
From: Jon Medhurst Tixy <hidden>
Date: 2014-02-03 14:25:40
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On Thu, 2014-01-23 at 15:05 -0500, David Long wrote:
From: "David A. Long" <redacted> Make the instruction interpreter call back to semantic action functions through a function pointer array provided by the invoker. The interpreter decodes the instructions into groups and uses the group number to index into the supplied array. kprobes and uprobes code will each supply their own array of functions. Signed-off-by: David A. Long <redacted> ---
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--- a/arch/arm/kernel/probes.c +++ b/arch/arm/kernel/probes.c@@ -378,10 +378,11 @@ static const int decode_struct_sizes[NUM_DECODE_TYPES] = { */ int __kprobes kprobe_decode_insn(kprobe_opcode_t insn, struct arch_specific_insn *asi, - const union decode_item *table, bool thumb) + const union decode_item *table, bool thumb, + const union decode_action *actions) { - const struct decode_header *h = (struct decode_header *)table; - const struct decode_header *next; + struct decode_header *h = (struct decode_header *)table; + struct decode_header *next;
The decode tables are fixed structures which nothing should want to modify, so I think the const's above should be kept. I believe that you've had to resort to changing them because the following typedef lacks a 'const' on the final argument.... [...]
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diff --git a/arch/arm/kernel/probes.h b/arch/arm/kernel/probes.h index c610fa9..81b6e61 100644
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+typedef enum kprobe_insn (probes_custom_decode_t)(kprobe_opcode_t, + struct arch_specific_insn *, + struct decode_header *); +
Adding 'const' above will also have the knock on effect of requiring const on all the 'custom decode' functions as well. -- Tixy