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powerpc: Don't use 'struct ppc_inst' to reference instruction location

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'struct ppc_inst' is an internal representation of an instruction, but
in-memory instructions are and will remain a table of 'u32' forever.

Replace all 'struct ppc_inst *' used for locating an instruction in
memory by 'u32 *'. This removes a lot of undue casts to 'struct
ppc_inst *'.

It also helps locating ab-use of 'struct ppc_inst' dereference.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
[mpe: Fix ppc_inst_next(), use u32 instead of unsigned int]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/7062722b087228e42cbd896e39bfdf526d6a340a.1621516826.git.christophe.leroy@csgroup.eu
This commit is contained in:
Christophe Leroy
2021-05-20 13:50:45 +00:00
committed by Michael Ellerman
parent e90a21ea80
commit 69d4d6e5fd
20 changed files with 159 additions and 176 deletions
Download Patch File Download Diff File Expand all files Collapse all files

49
arch/powerpc/lib/code-patching.c
View File

@@ -18,8 +18,7 @@
#include <asm/setup.h>
#include <asm/inst.h>
static int __patch_instruction(struct ppc_inst *exec_addr, struct ppc_inst instr,
struct ppc_inst *patch_addr)
static int __patch_instruction(u32 *exec_addr, struct ppc_inst instr, u32 *patch_addr)
{
if (!ppc_inst_prefixed(instr)) {
u32 val = ppc_inst_val(instr);
@@ -40,7 +39,7 @@ failed:
return -EFAULT;
}
int raw_patch_instruction(struct ppc_inst *addr, struct ppc_inst instr)
int raw_patch_instruction(u32 *addr, struct ppc_inst instr)
{
return __patch_instruction(addr, instr, addr);
}
@@ -148,10 +147,10 @@ static inline int unmap_patch_area(unsigned long addr)
return 0;
}
static int do_patch_instruction(struct ppc_inst *addr, struct ppc_inst instr)
static int do_patch_instruction(u32 *addr, struct ppc_inst instr)
{
int err;
struct ppc_inst *patch_addr = NULL;
u32 *patch_addr = NULL;
unsigned long flags;
unsigned long text_poke_addr;
unsigned long kaddr = (unsigned long)addr;
@@ -172,7 +171,7 @@ static int do_patch_instruction(struct ppc_inst *addr, struct ppc_inst instr)
goto out;
}
patch_addr = (struct ppc_inst *)(text_poke_addr + (kaddr & ~PAGE_MASK));
patch_addr = (u32 *)(text_poke_addr + (kaddr & ~PAGE_MASK));
__patch_instruction(addr, instr, patch_addr);
@@ -187,14 +186,14 @@ out:
}
#else /* !CONFIG_STRICT_KERNEL_RWX */
static int do_patch_instruction(struct ppc_inst *addr, struct ppc_inst instr)
static int do_patch_instruction(u32 *addr, struct ppc_inst instr)
{
return raw_patch_instruction(addr, instr);
}
#endif /* CONFIG_STRICT_KERNEL_RWX */
int patch_instruction(struct ppc_inst *addr, struct ppc_inst instr)
int patch_instruction(u32 *addr, struct ppc_inst instr)
{
/* Make sure we aren't patching a freed init section */
if (init_mem_is_free && init_section_contains(addr, 4)) {
@@ -205,7 +204,7 @@ int patch_instruction(struct ppc_inst *addr, struct ppc_inst instr)
}
NOKPROBE_SYMBOL(patch_instruction);
int patch_branch(struct ppc_inst *addr, unsigned long target, int flags)
int patch_branch(u32 *addr, unsigned long target, int flags)
{
struct ppc_inst instr;
@@ -257,8 +256,7 @@ bool is_conditional_branch(struct ppc_inst instr)
}
NOKPROBE_SYMBOL(is_conditional_branch);
int create_branch(struct ppc_inst *instr,
const struct ppc_inst *addr,
int create_branch(struct ppc_inst *instr, const u32 *addr,
unsigned long target, int flags)
{
long offset;
@@ -278,7 +276,7 @@ int create_branch(struct ppc_inst *instr,
return 0;
}
int create_cond_branch(struct ppc_inst *instr, const struct ppc_inst *addr,
int create_cond_branch(struct ppc_inst *instr, const u32 *addr,
unsigned long target, int flags)
{
long offset;
@@ -325,7 +323,7 @@ int instr_is_relative_link_branch(struct ppc_inst instr)
return instr_is_relative_branch(instr) && (ppc_inst_val(instr) & BRANCH_SET_LINK);
}
static unsigned long branch_iform_target(const struct ppc_inst *instr)
static unsigned long branch_iform_target(const u32 *instr)
{
signed long imm;
@@ -341,7 +339,7 @@ static unsigned long branch_iform_target(const struct ppc_inst *instr)
return (unsigned long)imm;
}
static unsigned long branch_bform_target(const struct ppc_inst *instr)
static unsigned long branch_bform_target(const u32 *instr)
{
signed long imm;
@@ -357,7 +355,7 @@ static unsigned long branch_bform_target(const struct ppc_inst *instr)
return (unsigned long)imm;
}
unsigned long branch_target(const struct ppc_inst *instr)
unsigned long branch_target(const u32 *instr)
{
if (instr_is_branch_iform(ppc_inst_read(instr)))
return branch_iform_target(instr);
@@ -367,8 +365,7 @@ unsigned long branch_target(const struct ppc_inst *instr)
return 0;
}
int translate_branch(struct ppc_inst *instr, const struct ppc_inst *dest,
const struct ppc_inst *src)
int translate_branch(struct ppc_inst *instr, const u32 *dest, const u32 *src)
{
unsigned long target;
target = branch_target(src);
@@ -395,13 +392,13 @@ void __patch_exception(int exc, unsigned long addr)
* instruction of the exception, not the first one
*/
patch_branch((struct ppc_inst *)(ibase + (exc / 4) + 1), addr, 0);
patch_branch(ibase + (exc / 4) + 1, addr, 0);
}
#endif
#ifdef CONFIG_CODE_PATCHING_SELFTEST
static int instr_is_branch_to_addr(const struct ppc_inst *instr, unsigned long addr)
static int instr_is_branch_to_addr(const u32 *instr, unsigned long addr)
{
if (instr_is_branch_iform(ppc_inst_read(instr)) ||
instr_is_branch_bform(ppc_inst_read(instr)))
@@ -423,7 +420,7 @@ static void __init test_branch_iform(void)
int err;
struct ppc_inst instr;
u32 tmp[2];
struct ppc_inst *iptr = (struct ppc_inst *)tmp;
u32 *iptr = tmp;
unsigned long addr = (unsigned long)tmp;
/* The simplest case, branch to self, no flags */
@@ -501,12 +498,12 @@ static void __init test_branch_iform(void)
static void __init test_create_function_call(void)
{
struct ppc_inst *iptr;
u32 *iptr;
unsigned long dest;
struct ppc_inst instr;
/* Check we can create a function call */
iptr = (struct ppc_inst *)ppc_function_entry(test_trampoline);
iptr = (u32 *)ppc_function_entry(test_trampoline);
dest = ppc_function_entry(test_create_function_call);
create_branch(&instr, iptr, dest, BRANCH_SET_LINK);
patch_instruction(iptr, instr);
@@ -517,11 +514,11 @@ static void __init test_branch_bform(void)
{
int err;
unsigned long addr;
struct ppc_inst *iptr, instr;
struct ppc_inst instr;
u32 tmp[2];
u32 *iptr = tmp;
unsigned int flags;
iptr = (struct ppc_inst *)tmp;
addr = (unsigned long)iptr;
/* The simplest case, branch to self, no flags */
@@ -726,9 +723,9 @@ static void __init test_prefixed_patching(void)
extern unsigned int code_patching_test1_expected[];
extern unsigned int end_code_patching_test1[];
__patch_instruction((struct ppc_inst *)code_patching_test1,
__patch_instruction(code_patching_test1,
ppc_inst_prefix(OP_PREFIX << 26, 0x00000000),
(struct ppc_inst *)code_patching_test1);
code_patching_test1);
check(!memcmp(code_patching_test1,
code_patching_test1_expected,