From f8faaffaa7d99028e457ef2d1dcb43a98f736938 Mon Sep 17 00:00:00 2001 From: Jordan Niethe Date: Wed, 6 May 2020 13:40:32 +1000 Subject: powerpc: Use a function for reading instructions Prefixed instructions will mean there are instructions of different length. As a result dereferencing a pointer to an instruction will not necessarily give the desired result. Introduce a function for reading instructions from memory into the instruction data type. Signed-off-by: Jordan Niethe Signed-off-by: Michael Ellerman Reviewed-by: Alistair Popple Link: https://lore.kernel.org/r/20200506034050.24806-13-jniethe5@gmail.com --- arch/powerpc/lib/code-patching.c | 26 ++++++++++++++------------ 1 file changed, 14 insertions(+), 12 deletions(-) (limited to 'arch/powerpc/lib/code-patching.c') diff --git a/arch/powerpc/lib/code-patching.c b/arch/powerpc/lib/code-patching.c index 1dff9d9d6645..435fc8e9f45d 100644 --- a/arch/powerpc/lib/code-patching.c +++ b/arch/powerpc/lib/code-patching.c @@ -348,9 +348,9 @@ static unsigned long branch_bform_target(const struct ppc_inst *instr) unsigned long branch_target(const struct ppc_inst *instr) { - if (instr_is_branch_iform(*instr)) + if (instr_is_branch_iform(ppc_inst_read(instr))) return branch_iform_target(instr); - else if (instr_is_branch_bform(*instr)) + else if (instr_is_branch_bform(ppc_inst_read(instr))) return branch_bform_target(instr); return 0; @@ -358,7 +358,8 @@ unsigned long branch_target(const struct ppc_inst *instr) int instr_is_branch_to_addr(const struct ppc_inst *instr, unsigned long addr) { - if (instr_is_branch_iform(*instr) || instr_is_branch_bform(*instr)) + if (instr_is_branch_iform(ppc_inst_read(instr)) || + instr_is_branch_bform(ppc_inst_read(instr))) return branch_target(instr) == addr; return 0; @@ -368,13 +369,14 @@ int translate_branch(struct ppc_inst *instr, const struct ppc_inst *dest, const struct ppc_inst *src) { unsigned long target; - target = branch_target(src); - if (instr_is_branch_iform(*src)) - return create_branch(instr, dest, target, ppc_inst_val(*src)); - else if (instr_is_branch_bform(*src)) - return create_cond_branch(instr, dest, target, ppc_inst_val(*src)); + if (instr_is_branch_iform(ppc_inst_read(src))) + return create_branch(instr, dest, target, + ppc_inst_val(ppc_inst_read(src))); + else if (instr_is_branch_bform(ppc_inst_read(src))) + return create_cond_branch(instr, dest, target, + ppc_inst_val(ppc_inst_read(src))); return 1; } @@ -598,7 +600,7 @@ static void __init test_translate_branch(void) patch_instruction(q, instr); check(instr_is_branch_to_addr(p, addr)); check(instr_is_branch_to_addr(q, addr)); - check(ppc_inst_equal(*q, ppc_inst(0x4a000000))); + check(ppc_inst_equal(ppc_inst_read(q), ppc_inst(0x4a000000))); /* Maximum positive case, move x to x - 32 MB + 4 */ p = buf + 0x2000000; @@ -609,7 +611,7 @@ static void __init test_translate_branch(void) patch_instruction(q, instr); check(instr_is_branch_to_addr(p, addr)); check(instr_is_branch_to_addr(q, addr)); - check(ppc_inst_equal(*q, ppc_inst(0x49fffffc))); + check(ppc_inst_equal(ppc_inst_read(q), ppc_inst(0x49fffffc))); /* Jump to x + 16 MB moved to x + 20 MB */ p = buf; @@ -655,7 +657,7 @@ static void __init test_translate_branch(void) patch_instruction(q, instr); check(instr_is_branch_to_addr(p, addr)); check(instr_is_branch_to_addr(q, addr)); - check(ppc_inst_equal(*q, ppc_inst(0x43ff8000))); + check(ppc_inst_equal(ppc_inst_read(q), ppc_inst(0x43ff8000))); /* Maximum positive case, move x to x - 32 KB + 4 */ p = buf + 0x8000; @@ -667,7 +669,7 @@ static void __init test_translate_branch(void) patch_instruction(q, instr); check(instr_is_branch_to_addr(p, addr)); check(instr_is_branch_to_addr(q, addr)); - check(ppc_inst_equal(*q, ppc_inst(0x43ff7ffc))); + check(ppc_inst_equal(ppc_inst_read(q), ppc_inst(0x43ff7ffc))); /* Jump to x + 12 KB moved to x + 20 KB */ p = buf; -- cgit v1.2.3