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authorJordan Niethe <jniethe5@gmail.com>2020-05-06 13:40:32 +1000
committerMichael Ellerman <mpe@ellerman.id.au>2020-05-19 00:10:37 +1000
commitf8faaffaa7d99028e457ef2d1dcb43a98f736938 (patch)
tree0e987e7b6862e3412816dec98b222f036931cdc8 /arch/powerpc/lib
parent94afd069d937d84fb4f696eb9a78db4084e43d21 (diff)
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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 <jniethe5@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Reviewed-by: Alistair Popple <alistair@popple.id.au> Link: https://lore.kernel.org/r/20200506034050.24806-13-jniethe5@gmail.com
Diffstat (limited to 'arch/powerpc/lib')
-rw-r--r--arch/powerpc/lib/code-patching.c26
-rw-r--r--arch/powerpc/lib/feature-fixups.c4
2 files changed, 16 insertions, 14 deletions
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;
diff --git a/arch/powerpc/lib/feature-fixups.c b/arch/powerpc/lib/feature-fixups.c
index fd978b8ee6d6..3c55097d406d 100644
--- a/arch/powerpc/lib/feature-fixups.c
+++ b/arch/powerpc/lib/feature-fixups.c
@@ -48,7 +48,7 @@ static int patch_alt_instruction(struct ppc_inst *src, struct ppc_inst *dest,
int err;
struct ppc_inst instr;
- instr = *src;
+ instr = ppc_inst_read(src);
if (instr_is_relative_branch(*src)) {
struct ppc_inst *target = (struct ppc_inst *)branch_target(src);
@@ -403,7 +403,7 @@ static void do_final_fixups(void)
length = (__end_interrupts - _stext) / sizeof(struct ppc_inst);
while (length--) {
- raw_patch_instruction(dest, *src);
+ raw_patch_instruction(dest, ppc_inst_read(src));
src++;
dest++;
}