* [PATCH v1 1/2] powerpc/inst: ppc_inst_as_u64() becomes ppc_inst_as_ulong()
@ 2021-04-06 9:38 Christophe Leroy
2021-04-06 9:38 ` [PATCH v1 2/2] powerpc: Enable OPTPROBES on PPC32 Christophe Leroy
0 siblings, 1 reply; 4+ messages in thread
From: Christophe Leroy @ 2021-04-06 9:38 UTC (permalink / raw)
To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman, naveen.n.rao
Cc: linuxppc-dev, linux-kernel
In order to simplify use on PPC32, change ppc_inst_as_u64()
into ppc_inst_as_ulong() that returns the 32 bits instruction
on PPC32.
Will be used when porting OPTPROBES to PPC32.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
arch/powerpc/include/asm/inst.h | 13 +++++++------
arch/powerpc/kernel/optprobes.c | 2 +-
arch/powerpc/lib/code-patching.c | 2 +-
arch/powerpc/xmon/xmon.c | 2 +-
4 files changed, 10 insertions(+), 9 deletions(-)
diff --git a/arch/powerpc/include/asm/inst.h b/arch/powerpc/include/asm/inst.h
index cc73c1267572..8ea0b503f32f 100644
--- a/arch/powerpc/include/asm/inst.h
+++ b/arch/powerpc/include/asm/inst.h
@@ -113,13 +113,14 @@ static inline struct ppc_inst *ppc_inst_next(void *location, struct ppc_inst *va
return location + ppc_inst_len(tmp);
}
-static inline u64 ppc_inst_as_u64(struct ppc_inst x)
+static inline unsigned long ppc_inst_as_ulong(struct ppc_inst x)
{
-#ifdef CONFIG_CPU_LITTLE_ENDIAN
- return (u64)ppc_inst_suffix(x) << 32 | ppc_inst_val(x);
-#else
- return (u64)ppc_inst_val(x) << 32 | ppc_inst_suffix(x);
-#endif
+ if (IS_ENABLED(CONFIG_PPC32))
+ return ppc_inst_val(x);
+ else if (IS_ENABLED(CONFIG_CPU_LITTLE_ENDIAN))
+ return (u64)ppc_inst_suffix(x) << 32 | ppc_inst_val(x);
+ else
+ return (u64)ppc_inst_val(x) << 32 | ppc_inst_suffix(x);
}
#define PPC_INST_STR_LEN sizeof("00000000 00000000")
diff --git a/arch/powerpc/kernel/optprobes.c b/arch/powerpc/kernel/optprobes.c
index 7f7cdbeacd1a..58fdb9f66e0f 100644
--- a/arch/powerpc/kernel/optprobes.c
+++ b/arch/powerpc/kernel/optprobes.c
@@ -264,7 +264,7 @@ int arch_prepare_optimized_kprobe(struct optimized_kprobe *op, struct kprobe *p)
* 3. load instruction to be emulated into relevant register, and
*/
temp = ppc_inst_read((struct ppc_inst *)p->ainsn.insn);
- patch_imm64_load_insns(ppc_inst_as_u64(temp), 4, buff + TMPL_INSN_IDX);
+ patch_imm64_load_insns(ppc_inst_as_ulong(temp), 4, buff + TMPL_INSN_IDX);
/*
* 4. branch back from trampoline
diff --git a/arch/powerpc/lib/code-patching.c b/arch/powerpc/lib/code-patching.c
index 65aec4d6d9ba..870b30d9be2f 100644
--- a/arch/powerpc/lib/code-patching.c
+++ b/arch/powerpc/lib/code-patching.c
@@ -26,7 +26,7 @@ static int __patch_instruction(struct ppc_inst *exec_addr, struct ppc_inst instr
__put_kernel_nofault(patch_addr, &val, u32, failed);
} else {
- u64 val = ppc_inst_as_u64(instr);
+ u64 val = ppc_inst_as_ulong(instr);
__put_kernel_nofault(patch_addr, &val, u64, failed);
}
diff --git a/arch/powerpc/xmon/xmon.c b/arch/powerpc/xmon/xmon.c
index 3fe37495f63d..ff10a357d41d 100644
--- a/arch/powerpc/xmon/xmon.c
+++ b/arch/powerpc/xmon/xmon.c
@@ -2980,7 +2980,7 @@ generic_inst_dump(unsigned long adr, long count, int praddr,
if (!ppc_inst_prefixed(inst))
dump_func(ppc_inst_val(inst), adr);
else
- dump_func(ppc_inst_as_u64(inst), adr);
+ dump_func(ppc_inst_as_ulong(inst), adr);
printf("\n");
}
return adr - first_adr;
--
2.25.0
^ permalink raw reply related [flat|nested] 4+ messages in thread
* [PATCH v1 2/2] powerpc: Enable OPTPROBES on PPC32
2021-04-06 9:38 [PATCH v1 1/2] powerpc/inst: ppc_inst_as_u64() becomes ppc_inst_as_ulong() Christophe Leroy
@ 2021-04-06 9:38 ` Christophe Leroy
2021-04-20 6:51 ` Naveen N. Rao
0 siblings, 1 reply; 4+ messages in thread
From: Christophe Leroy @ 2021-04-06 9:38 UTC (permalink / raw)
To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman, naveen.n.rao
Cc: linuxppc-dev, linux-kernel
For that, create a 32 bits version of patch_imm64_load_insns()
and create a patch_imm_load_insns() which calls
patch_imm32_load_insns() on PPC32 and patch_imm64_load_insns()
on PPC64.
Adapt optprobes_head.S for PPC32. Use PPC_LL/PPC_STL macros instead
of raw ld/std, opt out things linked to paca and use stmw/lmw to
save/restore registers.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
arch/powerpc/Kconfig | 2 +-
arch/powerpc/kernel/optprobes.c | 24 +++++++++++++--
arch/powerpc/kernel/optprobes_head.S | 46 +++++++++++++++++++---------
3 files changed, 53 insertions(+), 19 deletions(-)
diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index c1344c05226c..49b538e54efb 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -227,7 +227,7 @@ config PPC
select HAVE_MOD_ARCH_SPECIFIC
select HAVE_NMI if PERF_EVENTS || (PPC64 && PPC_BOOK3S)
select HAVE_HARDLOCKUP_DETECTOR_ARCH if PPC64 && PPC_BOOK3S && SMP
- select HAVE_OPTPROBES if PPC64
+ select HAVE_OPTPROBES
select HAVE_PERF_EVENTS
select HAVE_PERF_EVENTS_NMI if PPC64
select HAVE_HARDLOCKUP_DETECTOR_PERF if PERF_EVENTS && HAVE_PERF_EVENTS_NMI && !HAVE_HARDLOCKUP_DETECTOR_ARCH
diff --git a/arch/powerpc/kernel/optprobes.c b/arch/powerpc/kernel/optprobes.c
index 58fdb9f66e0f..cdf87086fa33 100644
--- a/arch/powerpc/kernel/optprobes.c
+++ b/arch/powerpc/kernel/optprobes.c
@@ -141,11 +141,21 @@ void arch_remove_optimized_kprobe(struct optimized_kprobe *op)
}
}
+static void patch_imm32_load_insns(unsigned long val, int reg, kprobe_opcode_t *addr)
+{
+ patch_instruction((struct ppc_inst *)addr,
+ ppc_inst(PPC_RAW_LIS(reg, IMM_H(val))));
+ addr++;
+
+ patch_instruction((struct ppc_inst *)addr,
+ ppc_inst(PPC_RAW_ORI(reg, reg, IMM_L(val))));
+}
+
/*
* Generate instructions to load provided immediate 64-bit value
* to register 'reg' and patch these instructions at 'addr'.
*/
-static void patch_imm64_load_insns(unsigned long val, int reg, kprobe_opcode_t *addr)
+static void patch_imm64_load_insns(unsigned long long val, int reg, kprobe_opcode_t *addr)
{
/* lis reg,(op)@highest */
patch_instruction((struct ppc_inst *)addr,
@@ -177,6 +187,14 @@ static void patch_imm64_load_insns(unsigned long val, int reg, kprobe_opcode_t *
___PPC_RS(reg) | (val & 0xffff)));
}
+static void patch_imm_load_insns(unsigned long val, int reg, kprobe_opcode_t *addr)
+{
+ if (IS_ENABLED(CONFIG_PPC64))
+ patch_imm64_load_insns(val, reg, addr);
+ else
+ patch_imm32_load_insns(val, reg, addr);
+}
+
int arch_prepare_optimized_kprobe(struct optimized_kprobe *op, struct kprobe *p)
{
struct ppc_inst branch_op_callback, branch_emulate_step, temp;
@@ -230,7 +248,7 @@ int arch_prepare_optimized_kprobe(struct optimized_kprobe *op, struct kprobe *p)
* Fixup the template with instructions to:
* 1. load the address of the actual probepoint
*/
- patch_imm64_load_insns((unsigned long)op, 3, buff + TMPL_OP_IDX);
+ patch_imm_load_insns((unsigned long)op, 3, buff + TMPL_OP_IDX);
/*
* 2. branch to optimized_callback() and emulate_step()
@@ -264,7 +282,7 @@ int arch_prepare_optimized_kprobe(struct optimized_kprobe *op, struct kprobe *p)
* 3. load instruction to be emulated into relevant register, and
*/
temp = ppc_inst_read((struct ppc_inst *)p->ainsn.insn);
- patch_imm64_load_insns(ppc_inst_as_ulong(temp), 4, buff + TMPL_INSN_IDX);
+ patch_imm_load_insns(ppc_inst_as_ulong(temp), 4, buff + TMPL_INSN_IDX);
/*
* 4. branch back from trampoline
diff --git a/arch/powerpc/kernel/optprobes_head.S b/arch/powerpc/kernel/optprobes_head.S
index ff8ba4d3824d..49f31e554573 100644
--- a/arch/powerpc/kernel/optprobes_head.S
+++ b/arch/powerpc/kernel/optprobes_head.S
@@ -30,39 +30,47 @@ optinsn_slot:
.global optprobe_template_entry
optprobe_template_entry:
/* Create an in-memory pt_regs */
- stdu r1,-INT_FRAME_SIZE(r1)
+ PPC_STLU r1,-INT_FRAME_SIZE(r1)
SAVE_GPR(0,r1)
/* Save the previous SP into stack */
addi r0,r1,INT_FRAME_SIZE
- std r0,GPR1(r1)
+ PPC_STL r0,GPR1(r1)
+#ifdef CONFIG_PPC64
SAVE_10GPRS(2,r1)
SAVE_10GPRS(12,r1)
SAVE_10GPRS(22,r1)
+#else
+ stmw r2, GPR2(r1)
+#endif
/* Save SPRS */
mfmsr r5
- std r5,_MSR(r1)
+ PPC_STL r5,_MSR(r1)
li r5,0x700
- std r5,_TRAP(r1)
+ PPC_STL r5,_TRAP(r1)
li r5,0
- std r5,ORIG_GPR3(r1)
- std r5,RESULT(r1)
+ PPC_STL r5,ORIG_GPR3(r1)
+ PPC_STL r5,RESULT(r1)
mfctr r5
- std r5,_CTR(r1)
+ PPC_STL r5,_CTR(r1)
mflr r5
- std r5,_LINK(r1)
+ PPC_STL r5,_LINK(r1)
mfspr r5,SPRN_XER
- std r5,_XER(r1)
+ PPC_STL r5,_XER(r1)
mfcr r5
- std r5,_CCR(r1)
+ PPC_STL r5,_CCR(r1)
+#ifdef CONFIG_PPC64
lbz r5,PACAIRQSOFTMASK(r13)
std r5,SOFTE(r1)
+#endif
/*
* We may get here from a module, so load the kernel TOC in r2.
* The original TOC gets restored when pt_regs is restored
* further below.
*/
+#ifdef CONFIG_PPC64
ld r2,PACATOC(r13)
+#endif
.global optprobe_template_op_address
optprobe_template_op_address:
@@ -72,9 +80,11 @@ optprobe_template_op_address:
*/
nop
nop
+#ifdef CONFIG_PPC64
nop
nop
nop
+#endif
/* 2. pt_regs pointer in r4 */
addi r4,r1,STACK_FRAME_OVERHEAD
@@ -94,9 +104,11 @@ optprobe_template_insn:
/* 2, Pass instruction to be emulated in r4 */
nop
nop
+#ifdef CONFIG_PPC64
nop
nop
nop
+#endif
.global optprobe_template_call_emulate
optprobe_template_call_emulate:
@@ -107,20 +119,24 @@ optprobe_template_call_emulate:
* All done.
* Now, restore the registers...
*/
- ld r5,_MSR(r1)
+ PPC_LL r5,_MSR(r1)
mtmsr r5
- ld r5,_CTR(r1)
+ PPC_LL r5,_CTR(r1)
mtctr r5
- ld r5,_LINK(r1)
+ PPC_LL r5,_LINK(r1)
mtlr r5
- ld r5,_XER(r1)
+ PPC_LL r5,_XER(r1)
mtxer r5
- ld r5,_CCR(r1)
+ PPC_LL r5,_CCR(r1)
mtcr r5
REST_GPR(0,r1)
+#ifdef CONFIG_PPC64
REST_10GPRS(2,r1)
REST_10GPRS(12,r1)
REST_10GPRS(22,r1)
+#else
+ lmw r2, GPR2(r1)
+#endif
/* Restore the previous SP */
addi r1,r1,INT_FRAME_SIZE
--
2.25.0
^ permalink raw reply related [flat|nested] 4+ messages in thread
* Re: [PATCH v1 2/2] powerpc: Enable OPTPROBES on PPC32
2021-04-06 9:38 ` [PATCH v1 2/2] powerpc: Enable OPTPROBES on PPC32 Christophe Leroy
@ 2021-04-20 6:51 ` Naveen N. Rao
2021-04-20 13:37 ` Christophe Leroy
0 siblings, 1 reply; 4+ messages in thread
From: Naveen N. Rao @ 2021-04-20 6:51 UTC (permalink / raw)
To: Benjamin Herrenschmidt, Christophe Leroy, Michael Ellerman,
Paul Mackerras
Cc: linuxppc-dev, linux-kernel
Christophe Leroy wrote:
> For that, create a 32 bits version of patch_imm64_load_insns()
> and create a patch_imm_load_insns() which calls
> patch_imm32_load_insns() on PPC32 and patch_imm64_load_insns()
> on PPC64.
>
> Adapt optprobes_head.S for PPC32. Use PPC_LL/PPC_STL macros instead
> of raw ld/std, opt out things linked to paca and use stmw/lmw to
> save/restore registers.
>
> Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
> ---
> arch/powerpc/Kconfig | 2 +-
> arch/powerpc/kernel/optprobes.c | 24 +++++++++++++--
> arch/powerpc/kernel/optprobes_head.S | 46 +++++++++++++++++++---------
> 3 files changed, 53 insertions(+), 19 deletions(-)
Thanks for adding support for ppc32. It is good to see that it works
without too many changes.
>
> diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
> index c1344c05226c..49b538e54efb 100644
> --- a/arch/powerpc/Kconfig
> +++ b/arch/powerpc/Kconfig
> @@ -227,7 +227,7 @@ config PPC
> select HAVE_MOD_ARCH_SPECIFIC
> select HAVE_NMI if PERF_EVENTS || (PPC64 && PPC_BOOK3S)
> select HAVE_HARDLOCKUP_DETECTOR_ARCH if PPC64 && PPC_BOOK3S && SMP
> - select HAVE_OPTPROBES if PPC64
> + select HAVE_OPTPROBES
> select HAVE_PERF_EVENTS
> select HAVE_PERF_EVENTS_NMI if PPC64
> select HAVE_HARDLOCKUP_DETECTOR_PERF if PERF_EVENTS && HAVE_PERF_EVENTS_NMI && !HAVE_HARDLOCKUP_DETECTOR_ARCH
> diff --git a/arch/powerpc/kernel/optprobes.c b/arch/powerpc/kernel/optprobes.c
> index 58fdb9f66e0f..cdf87086fa33 100644
> --- a/arch/powerpc/kernel/optprobes.c
> +++ b/arch/powerpc/kernel/optprobes.c
> @@ -141,11 +141,21 @@ void arch_remove_optimized_kprobe(struct optimized_kprobe *op)
> }
> }
>
> +static void patch_imm32_load_insns(unsigned long val, int reg, kprobe_opcode_t *addr)
> +{
> + patch_instruction((struct ppc_inst *)addr,
> + ppc_inst(PPC_RAW_LIS(reg, IMM_H(val))));
> + addr++;
> +
> + patch_instruction((struct ppc_inst *)addr,
> + ppc_inst(PPC_RAW_ORI(reg, reg, IMM_L(val))));
> +}
> +
> /*
> * Generate instructions to load provided immediate 64-bit value
> * to register 'reg' and patch these instructions at 'addr'.
> */
> -static void patch_imm64_load_insns(unsigned long val, int reg, kprobe_opcode_t *addr)
> +static void patch_imm64_load_insns(unsigned long long val, int reg, kprobe_opcode_t *addr)
Do you really need this?
> {
> /* lis reg,(op)@highest */
> patch_instruction((struct ppc_inst *)addr,
> @@ -177,6 +187,14 @@ static void patch_imm64_load_insns(unsigned long val, int reg, kprobe_opcode_t *
> ___PPC_RS(reg) | (val & 0xffff)));
> }
>
> +static void patch_imm_load_insns(unsigned long val, int reg, kprobe_opcode_t *addr)
> +{
> + if (IS_ENABLED(CONFIG_PPC64))
> + patch_imm64_load_insns(val, reg, addr);
> + else
> + patch_imm32_load_insns(val, reg, addr);
> +}
> +
> int arch_prepare_optimized_kprobe(struct optimized_kprobe *op, struct kprobe *p)
> {
> struct ppc_inst branch_op_callback, branch_emulate_step, temp;
> @@ -230,7 +248,7 @@ int arch_prepare_optimized_kprobe(struct optimized_kprobe *op, struct kprobe *p)
> * Fixup the template with instructions to:
> * 1. load the address of the actual probepoint
> */
> - patch_imm64_load_insns((unsigned long)op, 3, buff + TMPL_OP_IDX);
> + patch_imm_load_insns((unsigned long)op, 3, buff + TMPL_OP_IDX);
>
> /*
> * 2. branch to optimized_callback() and emulate_step()
> @@ -264,7 +282,7 @@ int arch_prepare_optimized_kprobe(struct optimized_kprobe *op, struct kprobe *p)
> * 3. load instruction to be emulated into relevant register, and
> */
> temp = ppc_inst_read((struct ppc_inst *)p->ainsn.insn);
> - patch_imm64_load_insns(ppc_inst_as_ulong(temp), 4, buff + TMPL_INSN_IDX);
> + patch_imm_load_insns(ppc_inst_as_ulong(temp), 4, buff + TMPL_INSN_IDX);
>
> /*
> * 4. branch back from trampoline
> diff --git a/arch/powerpc/kernel/optprobes_head.S b/arch/powerpc/kernel/optprobes_head.S
> index ff8ba4d3824d..49f31e554573 100644
> --- a/arch/powerpc/kernel/optprobes_head.S
> +++ b/arch/powerpc/kernel/optprobes_head.S
> @@ -30,39 +30,47 @@ optinsn_slot:
> .global optprobe_template_entry
> optprobe_template_entry:
> /* Create an in-memory pt_regs */
> - stdu r1,-INT_FRAME_SIZE(r1)
> + PPC_STLU r1,-INT_FRAME_SIZE(r1)
> SAVE_GPR(0,r1)
> /* Save the previous SP into stack */
> addi r0,r1,INT_FRAME_SIZE
> - std r0,GPR1(r1)
> + PPC_STL r0,GPR1(r1)
> +#ifdef CONFIG_PPC64
> SAVE_10GPRS(2,r1)
> SAVE_10GPRS(12,r1)
> SAVE_10GPRS(22,r1)
> +#else
> + stmw r2, GPR2(r1)
> +#endif
> /* Save SPRS */
> mfmsr r5
> - std r5,_MSR(r1)
> + PPC_STL r5,_MSR(r1)
> li r5,0x700
> - std r5,_TRAP(r1)
> + PPC_STL r5,_TRAP(r1)
> li r5,0
> - std r5,ORIG_GPR3(r1)
> - std r5,RESULT(r1)
> + PPC_STL r5,ORIG_GPR3(r1)
> + PPC_STL r5,RESULT(r1)
> mfctr r5
> - std r5,_CTR(r1)
> + PPC_STL r5,_CTR(r1)
> mflr r5
> - std r5,_LINK(r1)
> + PPC_STL r5,_LINK(r1)
> mfspr r5,SPRN_XER
> - std r5,_XER(r1)
> + PPC_STL r5,_XER(r1)
> mfcr r5
> - std r5,_CCR(r1)
> + PPC_STL r5,_CCR(r1)
> +#ifdef CONFIG_PPC64
> lbz r5,PACAIRQSOFTMASK(r13)
> std r5,SOFTE(r1)
> +#endif
>
> /*
> * We may get here from a module, so load the kernel TOC in r2.
> * The original TOC gets restored when pt_regs is restored
> * further below.
> */
> +#ifdef CONFIG_PPC64
> ld r2,PACATOC(r13)
> +#endif
Are the ISA and ABI documents for ppc32 available publicly? I would have
thought that the TOC issues apply to ppc32 as well, but want to
understand why this isn't a problem there.
>
> .global optprobe_template_op_address
> optprobe_template_op_address:
> @@ -72,9 +80,11 @@ optprobe_template_op_address:
> */
> nop
> nop
> +#ifdef CONFIG_PPC64
> nop
> nop
> nop
> +#endif
> /* 2. pt_regs pointer in r4 */
> addi r4,r1,STACK_FRAME_OVERHEAD
>
> @@ -94,9 +104,11 @@ optprobe_template_insn:
> /* 2, Pass instruction to be emulated in r4 */
> nop
> nop
> +#ifdef CONFIG_PPC64
> nop
> nop
> nop
> +#endif
It would be nice to put these behind a macro so as to avoid these #ifdef
blocks here, as well as with the register save/restore sequence.
- Naveen
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [PATCH v1 2/2] powerpc: Enable OPTPROBES on PPC32
2021-04-20 6:51 ` Naveen N. Rao
@ 2021-04-20 13:37 ` Christophe Leroy
0 siblings, 0 replies; 4+ messages in thread
From: Christophe Leroy @ 2021-04-20 13:37 UTC (permalink / raw)
To: Naveen N. Rao, Benjamin Herrenschmidt, Michael Ellerman, Paul Mackerras
Cc: linuxppc-dev, linux-kernel
Le 20/04/2021 à 08:51, Naveen N. Rao a écrit :
> Christophe Leroy wrote:
>> For that, create a 32 bits version of patch_imm64_load_insns()
>> and create a patch_imm_load_insns() which calls
>> patch_imm32_load_insns() on PPC32 and patch_imm64_load_insns()
>> on PPC64.
>>
>> Adapt optprobes_head.S for PPC32. Use PPC_LL/PPC_STL macros instead
>> of raw ld/std, opt out things linked to paca and use stmw/lmw to
>> save/restore registers.
>>
>> Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
>> ---
>> arch/powerpc/Kconfig | 2 +-
>> arch/powerpc/kernel/optprobes.c | 24 +++++++++++++--
>> arch/powerpc/kernel/optprobes_head.S | 46 +++++++++++++++++++---------
>> 3 files changed, 53 insertions(+), 19 deletions(-)
>
> Thanks for adding support for ppc32. It is good to see that it works without too many changes.
>
>>
>> diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
>> index c1344c05226c..49b538e54efb 100644
>> --- a/arch/powerpc/Kconfig
>> +++ b/arch/powerpc/Kconfig
>> @@ -227,7 +227,7 @@ config PPC
>> select HAVE_MOD_ARCH_SPECIFIC
>> select HAVE_NMI if PERF_EVENTS || (PPC64 && PPC_BOOK3S)
>> select HAVE_HARDLOCKUP_DETECTOR_ARCH if PPC64 && PPC_BOOK3S && SMP
>> - select HAVE_OPTPROBES if PPC64
>> + select HAVE_OPTPROBES
>> select HAVE_PERF_EVENTS
>> select HAVE_PERF_EVENTS_NMI if PPC64
>> select HAVE_HARDLOCKUP_DETECTOR_PERF if PERF_EVENTS && HAVE_PERF_EVENTS_NMI &&
>> !HAVE_HARDLOCKUP_DETECTOR_ARCH
>> diff --git a/arch/powerpc/kernel/optprobes.c b/arch/powerpc/kernel/optprobes.c
>> index 58fdb9f66e0f..cdf87086fa33 100644
>> --- a/arch/powerpc/kernel/optprobes.c
>> +++ b/arch/powerpc/kernel/optprobes.c
>> @@ -141,11 +141,21 @@ void arch_remove_optimized_kprobe(struct optimized_kprobe *op)
>> }
>> }
>>
>> +static void patch_imm32_load_insns(unsigned long val, int reg, kprobe_opcode_t *addr)
>> +{
>> + patch_instruction((struct ppc_inst *)addr,
>> + ppc_inst(PPC_RAW_LIS(reg, IMM_H(val))));
>> + addr++;
>> +
>> + patch_instruction((struct ppc_inst *)addr,
>> + ppc_inst(PPC_RAW_ORI(reg, reg, IMM_L(val))));
>> +}
>> +
>> /*
>> * Generate instructions to load provided immediate 64-bit value
>> * to register 'reg' and patch these instructions at 'addr'.
>> */
>> -static void patch_imm64_load_insns(unsigned long val, int reg, kprobe_opcode_t *addr)
>> +static void patch_imm64_load_insns(unsigned long long val, int reg, kprobe_opcode_t *addr)
>
> Do you really need this?
Without it I get:
from arch/powerpc/kernel/optprobes.c:8:
arch/powerpc/kernel/optprobes.c: In function 'patch_imm64_load_insns':
arch/powerpc/kernel/optprobes.c:163:14: error: right shift count >= width of type
[-Werror=shift-count-overflow]
163 | ((val >> 48) & 0xffff)));
| ^~
./arch/powerpc/include/asm/inst.h:69:48: note: in definition of macro 'ppc_inst'
69 | #define ppc_inst(x) ((struct ppc_inst){ .val = x })
| ^
arch/powerpc/kernel/optprobes.c:169:31: error: right shift count >= width of type
[-Werror=shift-count-overflow]
169 | ___PPC_RS(reg) | ((val >> 32) & 0xffff)));
| ^~
./arch/powerpc/include/asm/inst.h:69:48: note: in definition of macro 'ppc_inst'
69 | #define ppc_inst(x) ((struct ppc_inst){ .val = x })
| ^
>
>> {
>> /* lis reg,(op)@highest */
>> patch_instruction((struct ppc_inst *)addr,
>> @@ -177,6 +187,14 @@ static void patch_imm64_load_insns(unsigned long val, int reg, kprobe_opcode_t *
>> ___PPC_RS(reg) | (val & 0xffff)));
>> }
>>
>> +static void patch_imm_load_insns(unsigned long val, int reg, kprobe_opcode_t *addr)
>> +{
>> + if (IS_ENABLED(CONFIG_PPC64))
>> + patch_imm64_load_insns(val, reg, addr);
>> + else
>> + patch_imm32_load_insns(val, reg, addr);
>> +}
>> +
>> int arch_prepare_optimized_kprobe(struct optimized_kprobe *op, struct kprobe *p)
>> {
>> struct ppc_inst branch_op_callback, branch_emulate_step, temp;
>> @@ -230,7 +248,7 @@ int arch_prepare_optimized_kprobe(struct optimized_kprobe *op, struct kprobe *p)
>> * Fixup the template with instructions to:
>> * 1. load the address of the actual probepoint
>> */
>> - patch_imm64_load_insns((unsigned long)op, 3, buff + TMPL_OP_IDX);
>> + patch_imm_load_insns((unsigned long)op, 3, buff + TMPL_OP_IDX);
>>
>> /*
>> * 2. branch to optimized_callback() and emulate_step()
>> @@ -264,7 +282,7 @@ int arch_prepare_optimized_kprobe(struct optimized_kprobe *op, struct kprobe *p)
>> * 3. load instruction to be emulated into relevant register, and
>> */
>> temp = ppc_inst_read((struct ppc_inst *)p->ainsn.insn);
>> - patch_imm64_load_insns(ppc_inst_as_ulong(temp), 4, buff + TMPL_INSN_IDX);
>> + patch_imm_load_insns(ppc_inst_as_ulong(temp), 4, buff + TMPL_INSN_IDX);
>>
>> /*
>> * 4. branch back from trampoline
>> diff --git a/arch/powerpc/kernel/optprobes_head.S b/arch/powerpc/kernel/optprobes_head.S
>> index ff8ba4d3824d..49f31e554573 100644
>> --- a/arch/powerpc/kernel/optprobes_head.S
>> +++ b/arch/powerpc/kernel/optprobes_head.S
>> @@ -30,39 +30,47 @@ optinsn_slot:
>> .global optprobe_template_entry
>> optprobe_template_entry:
>> /* Create an in-memory pt_regs */
>> - stdu r1,-INT_FRAME_SIZE(r1)
>> + PPC_STLU r1,-INT_FRAME_SIZE(r1)
>> SAVE_GPR(0,r1)
>> /* Save the previous SP into stack */
>> addi r0,r1,INT_FRAME_SIZE
>> - std r0,GPR1(r1)
>> + PPC_STL r0,GPR1(r1)
>> +#ifdef CONFIG_PPC64
>> SAVE_10GPRS(2,r1)
>> SAVE_10GPRS(12,r1)
>> SAVE_10GPRS(22,r1)
>> +#else
>> + stmw r2, GPR2(r1)
>> +#endif
>> /* Save SPRS */
>> mfmsr r5
>> - std r5,_MSR(r1)
>> + PPC_STL r5,_MSR(r1)
>> li r5,0x700
>> - std r5,_TRAP(r1)
>> + PPC_STL r5,_TRAP(r1)
>> li r5,0
>> - std r5,ORIG_GPR3(r1)
>> - std r5,RESULT(r1)
>> + PPC_STL r5,ORIG_GPR3(r1)
>> + PPC_STL r5,RESULT(r1)
>> mfctr r5
>> - std r5,_CTR(r1)
>> + PPC_STL r5,_CTR(r1)
>> mflr r5
>> - std r5,_LINK(r1)
>> + PPC_STL r5,_LINK(r1)
>> mfspr r5,SPRN_XER
>> - std r5,_XER(r1)
>> + PPC_STL r5,_XER(r1)
>> mfcr r5
>> - std r5,_CCR(r1)
>> + PPC_STL r5,_CCR(r1)
>> +#ifdef CONFIG_PPC64
>> lbz r5,PACAIRQSOFTMASK(r13)
>> std r5,SOFTE(r1)
>> +#endif
>>
>> /*
>> * We may get here from a module, so load the kernel TOC in r2.
>> * The original TOC gets restored when pt_regs is restored
>> * further below.
>> */
>> +#ifdef CONFIG_PPC64
>> ld r2,PACATOC(r13)
>> +#endif
>
> Are the ISA and ABI documents for ppc32 available publicly?
ABI: https://wiki.raptorcs.com/w/images/0/03/Power-Arch-32-bit-ABI-supp-1.0-Unified.pdf
ISA: https://www.nxp.com/files-static/product/doc/MPCFPE32B.pdf
> I would have thought that the TOC issues
> apply to ppc32 as well, but want to understand why this isn't a problem there.
r2 is the pointer to 'current' on PPC32.
No TOC.
>
>>
>> .global optprobe_template_op_address
>> optprobe_template_op_address:
>> @@ -72,9 +80,11 @@ optprobe_template_op_address:
>> */
>> nop
>> nop
>> +#ifdef CONFIG_PPC64
>> nop
>> nop
>> nop
>> +#endif
>> /* 2. pt_regs pointer in r4 */
>> addi r4,r1,STACK_FRAME_OVERHEAD
>>
>> @@ -94,9 +104,11 @@ optprobe_template_insn:
>> /* 2, Pass instruction to be emulated in r4 */
>> nop
>> nop
>> +#ifdef CONFIG_PPC64
>> nop
>> nop
>> nop
>> +#endif
>
> It would be nice to put these behind a macro so as to avoid these #ifdef blocks here, as well as
> with the register save/restore sequence.
>
Will see what I can do
Christophe
^ permalink raw reply [flat|nested] 4+ messages in thread
end of thread, other threads:[~2021-04-20 13:37 UTC | newest]
Thread overview: 4+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2021-04-06 9:38 [PATCH v1 1/2] powerpc/inst: ppc_inst_as_u64() becomes ppc_inst_as_ulong() Christophe Leroy
2021-04-06 9:38 ` [PATCH v1 2/2] powerpc: Enable OPTPROBES on PPC32 Christophe Leroy
2021-04-20 6:51 ` Naveen N. Rao
2021-04-20 13:37 ` Christophe Leroy
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