Re: [PATCH 3/3] powerpc/kprobes: Check return value of patch_instruction()
Steven Rostedt wrote: On Sat, 25 Apr 2020 10:11:56 + Christophe Leroy wrote: Sure it's be more explicit, but then more lines also. 3 lines for only one really usefull. With goto, I would look like: diff --git a/arch/powerpc/kernel/optprobes.c b/arch/powerpc/kernel/optprobes.c index 046485bb0a52..938208f824da 100644 --- a/arch/powerpc/kernel/optprobes.c +++ b/arch/powerpc/kernel/optprobes.c @@ -139,14 +139,14 @@ void arch_remove_optimized_kprobe(struct optimized_kprobe *op) } } -#define PATCH_INSN(addr, instr) \ +#define PATCH_INSN(addr, instr, label) \ With the explicit label as a parameter, makes it more evident that it will do something (like jump) with that label. I think I will also rename the macro to PATCH_INSN_OR_GOTO() to make it super evident :) I like this solution the best! Thanks for the feedback. - Naveen
Re: [PATCH 3/3] powerpc/kprobes: Check return value of patch_instruction()
Christophe Leroy wrote:
On 04/24/2020 06:26 PM, Naveen N. Rao wrote:
Steven Rostedt wrote:
On Thu, 23 Apr 2020 17:41:52 +0200
Christophe Leroy wrote:
> diff --git a/arch/powerpc/kernel/optprobes.c
b/arch/powerpc/kernel/optprobes.c
> index 024f7aad1952..046485bb0a52 100644
> --- a/arch/powerpc/kernel/optprobes.c
> +++ b/arch/powerpc/kernel/optprobes.c
> @@ -139,52 +139,67 @@ void arch_remove_optimized_kprobe(struct
optimized_kprobe *op)
> }
> }
> > +#define PATCH_INSN(addr, instr) \
> +do { \
> + int rc = patch_instruction((unsigned int *)(addr),
instr); \
> + if (rc) { \
> + pr_err("%s:%d Error patching instruction at 0x%pK (%pS):
%d\n", \
> + __func__, __LINE__, \
> + (void *)(addr), (void *)(addr), rc); \
> + return rc; \
> + } \
> +} while (0)
> +
I hate this kind of macro which hides the "return".
What about keeping the return action in the caller ?
Otherwise, what about implementing something based on the use of
goto, on the same model as unsafe_put_user() for instance ?
Thanks for the review.
I noticed this as a warning from checkpatch.pl, but this looked compact
and correct for use in the two following functions. You'll notice that I
added it just before the two functions this is used in.
I suppose 'goto err' is usable too, but the ftrace code (patch 2) will
end up with more changes. I'm also struggling to see how a 'goto' is
less offensive. I think Steve's suggestion below would be the better way
to go, to make things explicit.
Sure it's be more explicit, but then more lines also. 3 lines for only
one really usefull.
With goto, I would look like:
diff --git a/arch/powerpc/kernel/optprobes.c
b/arch/powerpc/kernel/optprobes.c
index 046485bb0a52..938208f824da 100644
--- a/arch/powerpc/kernel/optprobes.c
+++ b/arch/powerpc/kernel/optprobes.c
@@ -139,14 +139,14 @@ void arch_remove_optimized_kprobe(struct
optimized_kprobe *op)
}
}
-#define PATCH_INSN(addr, instr)
\
+#define PATCH_INSN(addr, instr, label)
\
do { \
int rc = patch_instruction((unsigned int *)(addr), instr); \
if (rc) {\
pr_err("%s:%d Error patching instruction at 0x%pK (%pS): %d\n",
\
__func__, __LINE__, \
(void *)(addr), (void *)(addr), rc); \
- return rc; \
+ goto label; \
}\
} while (0)
My earlier complaint was that this would still add a flow control
statement, so didn't look to immediately address your original concern.
However, I suppose introduction of an explicit label makes things a bit
better.
In addition:
@@ -291,23 +297,8 @@ int arch_prepare_optimized_kprobe(struct
optimized_kprobe *op, struct kprobe *p)
goto error;
}
- rc = patch_instruction(buff + TMPL_CALL_HDLR_IDX, branch_op_callback);
- if (rc) {
- pr_err("%s:%d: Error patching instruction at 0x%pK: %d\n",
- __func__, __LINE__,
- (void *)(buff + TMPL_CALL_HDLR_IDX), rc);
- rc = -EFAULT;
- goto error;
- }
-
- rc = patch_instruction(buff + TMPL_EMULATE_IDX, branch_emulate_step);
- if (rc) {
- pr_err("%s:%d: Error patching instruction at 0x%pK: %d\n",
- __func__, __LINE__,
- (void *)(buff + TMPL_EMULATE_IDX), rc);
- rc = -EFAULT;
- goto error;
- }
+ PATCH_INSN(buff + TMPL_CALL_HDLR_IDX, branch_op_callback, efault);
+ PATCH_INSN(buff + TMPL_EMULATE_IDX, branch_emulate_step, efault);
I like how this variant can cover additional uses of patch_instruction()
here.
I will use this variant. Thanks for the suggestion!
- Naveen
Re: [PATCH 3/3] powerpc/kprobes: Check return value of patch_instruction()
On Sat, 25 Apr 2020 10:11:56 +
Christophe Leroy wrote:
>
> Sure it's be more explicit, but then more lines also. 3 lines for only
> one really usefull.
>
> With goto, I would look like:
>
> diff --git a/arch/powerpc/kernel/optprobes.c
> b/arch/powerpc/kernel/optprobes.c
> index 046485bb0a52..938208f824da 100644
> --- a/arch/powerpc/kernel/optprobes.c
> +++ b/arch/powerpc/kernel/optprobes.c
> @@ -139,14 +139,14 @@ void arch_remove_optimized_kprobe(struct
> optimized_kprobe *op)
> }
> }
>
> -#define PATCH_INSN(addr, instr)
> \
> +#define PATCH_INSN(addr, instr, label)
> \
With the explicit label as a parameter, makes it more evident that it
will do something (like jump) with that label.
I like this solution the best!
-- Steve
> do {
> \
> int rc = patch_instruction((unsigned int *)(addr), instr); \
> if (rc) {\
> pr_err("%s:%d Error patching instruction at 0x%pK (%pS): %d\n",
> \
> __func__, __LINE__, \
> (void *)(addr), (void *)(addr), rc); \
> - return rc; \
> + goto label; \
> }\
> } while (0)
>
Re: [PATCH 3/3] powerpc/kprobes: Check return value of patch_instruction()
On 04/24/2020 06:26 PM, Naveen N. Rao wrote:
Steven Rostedt wrote:
On Thu, 23 Apr 2020 17:41:52 +0200
Christophe Leroy wrote:
> diff --git a/arch/powerpc/kernel/optprobes.c
b/arch/powerpc/kernel/optprobes.c
> index 024f7aad1952..046485bb0a52 100644
> --- a/arch/powerpc/kernel/optprobes.c
> +++ b/arch/powerpc/kernel/optprobes.c
> @@ -139,52 +139,67 @@ void arch_remove_optimized_kprobe(struct
optimized_kprobe *op)
> }
> }
> > +#define PATCH_INSN(addr, instr) \
> +do { \
> + int rc = patch_instruction((unsigned int *)(addr),
instr); \
> + if (rc) { \
> + pr_err("%s:%d Error patching instruction at 0x%pK (%pS):
%d\n", \
> + __func__, __LINE__, \
> + (void *)(addr), (void *)(addr), rc); \
> + return rc; \
> + } \
> +} while (0)
> +
I hate this kind of macro which hides the "return".
What about keeping the return action in the caller ?
Otherwise, what about implementing something based on the use of
goto, on the same model as unsafe_put_user() for instance ?
Thanks for the review.
I noticed this as a warning from checkpatch.pl, but this looked compact
and correct for use in the two following functions. You'll notice that I
added it just before the two functions this is used in.
I suppose 'goto err' is usable too, but the ftrace code (patch 2) will
end up with more changes. I'm also struggling to see how a 'goto' is
less offensive. I think Steve's suggestion below would be the better way
to go, to make things explicit.
Sure it's be more explicit, but then more lines also. 3 lines for only
one really usefull.
With goto, I would look like:
diff --git a/arch/powerpc/kernel/optprobes.c
b/arch/powerpc/kernel/optprobes.c
index 046485bb0a52..938208f824da 100644
--- a/arch/powerpc/kernel/optprobes.c
+++ b/arch/powerpc/kernel/optprobes.c
@@ -139,14 +139,14 @@ void arch_remove_optimized_kprobe(struct
optimized_kprobe *op)
}
}
-#define PATCH_INSN(addr, instr)
\
+#define PATCH_INSN(addr, instr, label)
\
do {\
int rc = patch_instruction((unsigned int *)(addr), instr); \
if (rc) {\
pr_err("%s:%d Error patching instruction at 0x%pK (%pS): %d\n",
\
__func__, __LINE__, \
(void *)(addr), (void *)(addr), rc); \
- return rc; \
+ goto label; \
}\
} while (0)
@@ -159,14 +159,17 @@ static int patch_imm32_load_insns(unsigned int
val, kprobe_opcode_t *addr)
{
/* addis r4,0,(insn)@h */
PATCH_INSN(addr, PPC_INST_ADDIS | ___PPC_RT(4) |
- ((val >> 16) & 0x));
+ ((val >> 16) & 0x), failed);
addr++;
/* ori r4,r4,(insn)@l */
PATCH_INSN(addr, PPC_INST_ORI | ___PPC_RA(4) |
- ___PPC_RS(4) | (val & 0x));
+ ___PPC_RS(4) | (val & 0x), failed);
return 0;
+
+failed:
+ return -EFAULT;
}
/*
@@ -177,29 +180,32 @@ static int patch_imm64_load_insns(unsigned long
val, kprobe_opcode_t *addr)
{
/* lis r3,(op)@highest */
PATCH_INSN(addr, PPC_INST_ADDIS | ___PPC_RT(3) |
- ((val >> 48) & 0x));
+ ((val >> 48) & 0x), failed);
addr++;
/* ori r3,r3,(op)@higher */
PATCH_INSN(addr, PPC_INST_ORI | ___PPC_RA(3) |
- ___PPC_RS(3) | ((val >> 32) & 0x));
+ ___PPC_RS(3) | ((val >> 32) & 0x), failed);
addr++;
/* rldicr r3,r3,32,31 */
PATCH_INSN(addr, PPC_INST_RLDICR | ___PPC_RA(3) |
- ___PPC_RS(3) | __PPC_SH64(32) | __PPC_ME64(31));
+ ___PPC_RS(3) | __PPC_SH64(32) | __PPC_ME64(31),
failed);
addr++;
/* oris r3,r3,(op)@h */
PATCH_INSN(addr, PPC_INST_ORIS | ___PPC_RA(3) |
- ___PPC_RS(3) | ((val >> 16) & 0x));
+ ___PPC_RS(3) | ((val >> 16) & 0x), failed);
addr++;
/* ori r3,r3,(op)@l */
PATCH_INSN(addr, PPC_INST_ORI | ___PPC_RA(3) |
- ___PPC_RS(3) | (val & 0x));
+ ___PPC_RS(3) | (val & 0x), failed);
return 0;
+
+failed:
+ return -EFAULT;
}
Re: [PATCH 3/3] powerpc/kprobes: Check return value of patch_instruction()
Steven Rostedt wrote:
On Fri, 24 Apr 2020 23:56:25 +0530
"Naveen N. Rao" wrote:
> #define PATCH_INSN(addr, instr) \
> ({
>int rc = patch_instruction((unsigned int *)(addr), instr); \
>if (rc) \
>pr_err("%s:%d Error patching instruction at 0x%pK (%pS): %d\n", \
>__func__, __LINE__, \
>(void *)(addr), (void *)(addr), rc); \
>rc; \
> })
>
>
> Then you can just do:
>
> ret = PATCH_INSN(...);
>if (ret)
>return ret;
>
> in the code.
That's really nice. However, in this case, I guess I can simply use an
inline function? The primary reason I used the macro was for including a
'return' statement in it.
I thought the primary reason was the __func__, __LINE__ which wont work as
expected as an inline.
Ugh, you're right indeed. I clearly didn't think it through. :facepalm:
I'll use this variant.
Regards,
Naveen
Re: [PATCH 3/3] powerpc/kprobes: Check return value of patch_instruction()
On Fri, 24 Apr 2020 23:56:25 +0530
"Naveen N. Rao" wrote:
> > #define PATCH_INSN(addr, instr) \
> > ({
> > int rc = patch_instruction((unsigned int *)(addr), instr); \
> > if (rc) \
> > pr_err("%s:%d Error patching instruction at 0x%pK (%pS): %d\n",
> > \
> > __func__, __LINE__, \
> > (void *)(addr), (void *)(addr), rc); \
> > rc; \
> > })
> >
> >
> > Then you can just do:
> >
> > ret = PATCH_INSN(...);
> > if (ret)
> > return ret;
> >
> > in the code.
>
> That's really nice. However, in this case, I guess I can simply use an
> inline function? The primary reason I used the macro was for including a
> 'return' statement in it.
I thought the primary reason was the __func__, __LINE__ which wont work as
expected as an inline.
-- Steve
Re: [PATCH 3/3] powerpc/kprobes: Check return value of patch_instruction()
Steven Rostedt wrote:
On Thu, 23 Apr 2020 17:41:52 +0200
Christophe Leroy wrote:
> diff --git a/arch/powerpc/kernel/optprobes.c b/arch/powerpc/kernel/optprobes.c
> index 024f7aad1952..046485bb0a52 100644
> --- a/arch/powerpc/kernel/optprobes.c
> +++ b/arch/powerpc/kernel/optprobes.c
> @@ -139,52 +139,67 @@ void arch_remove_optimized_kprobe(struct
optimized_kprobe *op)
>}
> }
>
> +#define PATCH_INSN(addr, instr) \
> +do {
\
> + int rc = patch_instruction((unsigned int *)(addr), instr); \
> + if (rc) {\
> + pr_err("%s:%d Error patching instruction at 0x%pK (%pS): %d\n", \
> + __func__, __LINE__, \
> + (void *)(addr), (void *)(addr), rc); \
> + return rc; \
> + }\
> +} while (0)
> +
I hate this kind of macro which hides the "return".
What about keeping the return action in the caller ?
Otherwise, what about implementing something based on the use of goto,
on the same model as unsafe_put_user() for instance ?
Thanks for the review.
I noticed this as a warning from checkpatch.pl, but this looked compact
and correct for use in the two following functions. You'll notice that I
added it just before the two functions this is used in.
I suppose 'goto err' is usable too, but the ftrace code (patch 2) will
end up with more changes. I'm also struggling to see how a 'goto' is
less offensive. I think Steve's suggestion below would be the better way
to go, to make things explicit.
#define PATCH_INSN(addr, instr) \
({
int rc = patch_instruction((unsigned int *)(addr), instr); \
if (rc) \
pr_err("%s:%d Error patching instruction at 0x%pK (%pS): %d\n",
\
__func__, __LINE__, \
(void *)(addr), (void *)(addr), rc); \
rc; \
})
Then you can just do:
ret = PATCH_INSN(...);
if (ret)
return ret;
in the code.
That's really nice. However, in this case, I guess I can simply use an
inline function? The primary reason I used the macro was for including a
'return' statement in it.
Thanks for the review!
- Naveen
Re: [PATCH 3/3] powerpc/kprobes: Check return value of patch_instruction()
On Thu, 23 Apr 2020 17:41:52 +0200
Christophe Leroy wrote:
> > diff --git a/arch/powerpc/kernel/optprobes.c
> > b/arch/powerpc/kernel/optprobes.c
> > index 024f7aad1952..046485bb0a52 100644
> > --- a/arch/powerpc/kernel/optprobes.c
> > +++ b/arch/powerpc/kernel/optprobes.c
> > @@ -139,52 +139,67 @@ void arch_remove_optimized_kprobe(struct
> > optimized_kprobe *op)
> > }
> > }
> >
> > +#define PATCH_INSN(addr, instr)
> > \
> > +do {
> > \
> > + int rc = patch_instruction((unsigned int *)(addr), instr); \
> > + if (rc) {\
> > + pr_err("%s:%d Error patching instruction at 0x%pK (%pS): %d\n",
> > \
> > + __func__, __LINE__, \
> > + (void *)(addr), (void *)(addr), rc); \
> > + return rc; \
> > + }\
> > +} while (0)
> > +
>
> I hate this kind of macro which hides the "return".
>
> What about keeping the return action in the caller ?
>
> Otherwise, what about implementing something based on the use of goto,
> on the same model as unsafe_put_user() for instance ?
#define PATCH_INSN(addr, instr) \
({
int rc = patch_instruction((unsigned int *)(addr), instr); \
if (rc) \
pr_err("%s:%d Error patching instruction at 0x%pK (%pS): %d\n",
\
__func__, __LINE__, \
(void *)(addr), (void *)(addr), rc); \
rc; \
})
Then you can just do:
ret = PATCH_INSN(...);
if (ret)
return ret;
in the code.
-- Steve
Re: [PATCH 3/3] powerpc/kprobes: Check return value of patch_instruction()
Le 23/04/2020 à 17:09, Naveen N. Rao a écrit :
patch_instruction() can fail in some scenarios. Add appropriate error
checking so that such failures are caught and logged, and suitable error
code is returned.
Fixes: d07df82c43be8 ("powerpc/kprobes: Move kprobes over to
patch_instruction()")
Fixes: f3eca95638931 ("powerpc/kprobes/optprobes: Use patch_instruction()")
Signed-off-by: Naveen N. Rao
---
arch/powerpc/kernel/kprobes.c | 10 +++-
arch/powerpc/kernel/optprobes.c | 99 ++---
2 files changed, 87 insertions(+), 22 deletions(-)
diff --git a/arch/powerpc/kernel/kprobes.c b/arch/powerpc/kernel/kprobes.c
index 81efb605113e..4a297ae2bd87 100644
--- a/arch/powerpc/kernel/kprobes.c
+++ b/arch/powerpc/kernel/kprobes.c
@@ -138,13 +138,19 @@ NOKPROBE_SYMBOL(arch_prepare_kprobe);
void arch_arm_kprobe(struct kprobe *p)
{
- patch_instruction(p->addr, BREAKPOINT_INSTRUCTION);
+ int rc = patch_instruction(p->addr, BREAKPOINT_INSTRUCTION);
+
+ if (rc)
+ WARN("Failed to patch trap at 0x%pK: %d\n", (void *)p->addr,
rc);
}
NOKPROBE_SYMBOL(arch_arm_kprobe);
void arch_disarm_kprobe(struct kprobe *p)
{
- patch_instruction(p->addr, p->opcode);
+ int rc = patch_instruction(p->addr, p->opcode);
+
+ if (rc)
+ WARN("Failed to remove trap at 0x%pK: %d\n", (void *)p->addr,
rc);
}
NOKPROBE_SYMBOL(arch_disarm_kprobe);
diff --git a/arch/powerpc/kernel/optprobes.c b/arch/powerpc/kernel/optprobes.c
index 024f7aad1952..046485bb0a52 100644
--- a/arch/powerpc/kernel/optprobes.c
+++ b/arch/powerpc/kernel/optprobes.c
@@ -139,52 +139,67 @@ void arch_remove_optimized_kprobe(struct optimized_kprobe
*op)
}
}
+#define PATCH_INSN(addr, instr) \
+do {\
+ int rc = patch_instruction((unsigned int *)(addr), instr); \
+ if (rc) {\
+ pr_err("%s:%d Error patching instruction at 0x%pK (%pS): %d\n",
\
+ __func__, __LINE__, \
+ (void *)(addr), (void *)(addr), rc); \
+ return rc; \
+ }\
+} while (0)
+
I hate this kind of macro which hides the "return".
What about keeping the return action in the caller ?
Otherwise, what about implementing something based on the use of goto,
on the same model as unsafe_put_user() for instance ?
Christophe
[PATCH 3/3] powerpc/kprobes: Check return value of patch_instruction()
patch_instruction() can fail in some scenarios. Add appropriate error
checking so that such failures are caught and logged, and suitable error
code is returned.
Fixes: d07df82c43be8 ("powerpc/kprobes: Move kprobes over to
patch_instruction()")
Fixes: f3eca95638931 ("powerpc/kprobes/optprobes: Use patch_instruction()")
Signed-off-by: Naveen N. Rao
---
arch/powerpc/kernel/kprobes.c | 10 +++-
arch/powerpc/kernel/optprobes.c | 99 ++---
2 files changed, 87 insertions(+), 22 deletions(-)
diff --git a/arch/powerpc/kernel/kprobes.c b/arch/powerpc/kernel/kprobes.c
index 81efb605113e..4a297ae2bd87 100644
--- a/arch/powerpc/kernel/kprobes.c
+++ b/arch/powerpc/kernel/kprobes.c
@@ -138,13 +138,19 @@ NOKPROBE_SYMBOL(arch_prepare_kprobe);
void arch_arm_kprobe(struct kprobe *p)
{
- patch_instruction(p->addr, BREAKPOINT_INSTRUCTION);
+ int rc = patch_instruction(p->addr, BREAKPOINT_INSTRUCTION);
+
+ if (rc)
+ WARN("Failed to patch trap at 0x%pK: %d\n", (void *)p->addr,
rc);
}
NOKPROBE_SYMBOL(arch_arm_kprobe);
void arch_disarm_kprobe(struct kprobe *p)
{
- patch_instruction(p->addr, p->opcode);
+ int rc = patch_instruction(p->addr, p->opcode);
+
+ if (rc)
+ WARN("Failed to remove trap at 0x%pK: %d\n", (void *)p->addr,
rc);
}
NOKPROBE_SYMBOL(arch_disarm_kprobe);
diff --git a/arch/powerpc/kernel/optprobes.c b/arch/powerpc/kernel/optprobes.c
index 024f7aad1952..046485bb0a52 100644
--- a/arch/powerpc/kernel/optprobes.c
+++ b/arch/powerpc/kernel/optprobes.c
@@ -139,52 +139,67 @@ void arch_remove_optimized_kprobe(struct optimized_kprobe
*op)
}
}
+#define PATCH_INSN(addr, instr)
\
+do {\
+ int rc = patch_instruction((unsigned int *)(addr), instr); \
+ if (rc) {\
+ pr_err("%s:%d Error patching instruction at 0x%pK (%pS): %d\n",
\
+ __func__, __LINE__, \
+ (void *)(addr), (void *)(addr), rc); \
+ return rc; \
+ }\
+} while (0)
+
/*
* emulate_step() requires insn to be emulated as
* second parameter. Load register 'r4' with the
* instruction.
*/
-void patch_imm32_load_insns(unsigned int val, kprobe_opcode_t *addr)
+static int patch_imm32_load_insns(unsigned int val, kprobe_opcode_t *addr)
{
/* addis r4,0,(insn)@h */
- patch_instruction(addr, PPC_INST_ADDIS | ___PPC_RT(4) |
+ PATCH_INSN(addr, PPC_INST_ADDIS | ___PPC_RT(4) |
((val >> 16) & 0x));
addr++;
/* ori r4,r4,(insn)@l */
- patch_instruction(addr, PPC_INST_ORI | ___PPC_RA(4) |
+ PATCH_INSN(addr, PPC_INST_ORI | ___PPC_RA(4) |
___PPC_RS(4) | (val & 0x));
+
+ return 0;
}
/*
* Generate instructions to load provided immediate 64-bit value
* to register 'r3' and patch these instructions at 'addr'.
*/
-void patch_imm64_load_insns(unsigned long val, kprobe_opcode_t *addr)
+static int patch_imm64_load_insns(unsigned long val, kprobe_opcode_t *addr)
{
/* lis r3,(op)@highest */
- patch_instruction(addr, PPC_INST_ADDIS | ___PPC_RT(3) |
+ PATCH_INSN(addr, PPC_INST_ADDIS | ___PPC_RT(3) |
((val >> 48) & 0x));
addr++;
/* ori r3,r3,(op)@higher */
- patch_instruction(addr, PPC_INST_ORI | ___PPC_RA(3) |
+ PATCH_INSN(addr, PPC_INST_ORI | ___PPC_RA(3) |
___PPC_RS(3) | ((val >> 32) & 0x));
addr++;
/* rldicr r3,r3,32,31 */
- patch_instruction(addr, PPC_INST_RLDICR | ___PPC_RA(3) |
+ PATCH_INSN(addr, PPC_INST_RLDICR | ___PPC_RA(3) |
___PPC_RS(3) | __PPC_SH64(32) | __PPC_ME64(31));
addr++;
/* oris r3,r3,(op)@h */
- patch_instruction(addr, PPC_INST_ORIS | ___PPC_RA(3) |
+ PATCH_INSN(addr, PPC_INST_ORIS | ___PPC_RA(3) |
___PPC_RS(3) | ((val >> 16) & 0x));
addr++;
/* ori r3,r3,(op)@l */
- patch_instruction(addr, PPC_INST_ORI | ___PPC_RA(3) |
+ PATCH_INSN(addr, PPC_INST_ORI | ___PPC_RA(3) |
___PPC_RS(3) | (val & 0x));
+
+ return 0;
}
int arch_prepare_optimized_kprobe(struct optimized_kprobe *op, struct kprobe
*p)
@@ -216,14 +231,18 @@ int arch_prepare_optimized_kprobe(struct optimized_kprobe
*op, struct kprobe *p)
* be within 32MB on either side of the current instruction.
*/
b_offset = (unsigned long)buff - (unsigned long)p->addr;
- if (!is_offset_in_branch_range(b_offset))
+
