| Message ID | 1439254364-15362-2-git-send-email-dave.long@linaro.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Hi David, On Tue, Aug 11, 2015 at 01:52:38AM +0100, David Long wrote: > From: "David A. Long" <dave.long@linaro.org> > > Add HAVE_REGS_AND_STACK_ACCESS_API feature for arm64. > > Signed-off-by: David A. Long <dave.long@linaro.org> > --- > arch/arm64/Kconfig | 1 + > arch/arm64/include/asm/ptrace.h | 25 +++++++++++++ > arch/arm64/kernel/ptrace.c | 77 +++++++++++++++++++++++++++++++++++++++++ > 3 files changed, 103 insertions(+) > > diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig > index 318175f..ef5d726 100644 > --- a/arch/arm64/Kconfig > +++ b/arch/arm64/Kconfig > @@ -70,6 +70,7 @@ config ARM64 > select HAVE_PERF_EVENTS > select HAVE_PERF_REGS > select HAVE_PERF_USER_STACK_DUMP > + select HAVE_REGS_AND_STACK_ACCESS_API > select HAVE_RCU_TABLE_FREE > select HAVE_SYSCALL_TRACEPOINTS > select IRQ_DOMAIN > diff --git a/arch/arm64/include/asm/ptrace.h b/arch/arm64/include/asm/ptrace.h > index d6dd9fd..8f440e9 100644 > --- a/arch/arm64/include/asm/ptrace.h > +++ b/arch/arm64/include/asm/ptrace.h > @@ -118,6 +118,8 @@ struct pt_regs { > u64 syscallno; > }; > > +#define MAX_REG_OFFSET (sizeof(struct user_pt_regs) - sizeof(u64)) Can you not use offset_of(struct user_pt_regs, pstate) here? > + > #define arch_has_single_step() (1) > > #ifdef CONFIG_COMPAT > @@ -146,6 +148,29 @@ struct pt_regs { > #define user_stack_pointer(regs) \ > (!compat_user_mode(regs) ? (regs)->sp : (regs)->compat_sp) > > +/** > + * regs_get_register() - get register value from its offset > + * @regs: pt_regs from which register value is gotten > + * @offset: offset number of the register. > + * > + * regs_get_register returns the value of a register whose offset from @regs. > + * The @offset is the offset of the register in struct pt_regs. > + * If @offset is bigger than MAX_REG_OFFSET, this returns 0. > + */ > +static inline u64 regs_get_register(struct pt_regs *regs, > + unsigned int offset) > +{ > + if (unlikely(offset > MAX_REG_OFFSET)) > + return 0; > + return *(u64 *)((u64)regs + offset); > +} Is this guaranteed only to be called on kernel-mode regs, or do we need to deal with compat tasks too? > + > +/* Valid only for Kernel mode traps. */ > +static inline unsigned long kernel_stack_pointer(struct pt_regs *regs) > +{ > + return regs->sp; > +} > + > static inline unsigned long regs_return_value(struct pt_regs *regs) > { > return regs->regs[0]; > diff --git a/arch/arm64/kernel/ptrace.c b/arch/arm64/kernel/ptrace.c > index d882b83..f6199a5 100644 > --- a/arch/arm64/kernel/ptrace.c > +++ b/arch/arm64/kernel/ptrace.c > @@ -48,6 +48,83 @@ > #define CREATE_TRACE_POINTS > #include <trace/events/syscalls.h> > > +#define ARM_pstate pstate > +#define ARM_pc pc > +#define ARM_sp sp > +#define ARM_x30 regs[30] > +#define ARM_x29 regs[29] > +#define ARM_x28 regs[28] > +#define ARM_x27 regs[27] > +#define ARM_x26 regs[26] > +#define ARM_x25 regs[25] > +#define ARM_x24 regs[24] > +#define ARM_x23 regs[23] > +#define ARM_x22 regs[22] > +#define ARM_x21 regs[21] > +#define ARM_x20 regs[20] > +#define ARM_x19 regs[19] > +#define ARM_x18 regs[18] > +#define ARM_x17 regs[17] > +#define ARM_x16 regs[16] > +#define ARM_x15 regs[15] > +#define ARM_x14 regs[14] > +#define ARM_x13 regs[13] > +#define ARM_x12 regs[12] > +#define ARM_x11 regs[11] > +#define ARM_x10 regs[10] > +#define ARM_x9 regs[9] > +#define ARM_x8 regs[8] > +#define ARM_x7 regs[7] > +#define ARM_x6 regs[6] > +#define ARM_x5 regs[5] > +#define ARM_x4 regs[4] > +#define ARM_x3 regs[3] > +#define ARM_x2 regs[2] > +#define ARM_x1 regs[1] > +#define ARM_x0 regs[0] I've said it before, but I really don't like these macros. I'd rather rework the following REG_OFFSET_NAME to be GPR_OFFSET_NAME which could prefix the "x" in the name field. > + > +#define REG_OFFSET_NAME(r) \ > + {.name = #r, .offset = offsetof(struct pt_regs, ARM_##r)} > +#define REG_OFFSET_END {.name = NULL, .offset = 0} > + > +const struct pt_regs_offset regs_offset_table[] = { > + REG_OFFSET_NAME(x0), > + REG_OFFSET_NAME(x1), > + REG_OFFSET_NAME(x2), > + REG_OFFSET_NAME(x3), > + REG_OFFSET_NAME(x4), > + REG_OFFSET_NAME(x5), > + REG_OFFSET_NAME(x6), > + REG_OFFSET_NAME(x7), > + REG_OFFSET_NAME(x8), > + REG_OFFSET_NAME(x9), > + REG_OFFSET_NAME(x10), > + REG_OFFSET_NAME(x11), > + REG_OFFSET_NAME(x12), > + REG_OFFSET_NAME(x13), > + REG_OFFSET_NAME(x14), > + REG_OFFSET_NAME(x15), > + REG_OFFSET_NAME(x16), > + REG_OFFSET_NAME(x17), > + REG_OFFSET_NAME(x18), > + REG_OFFSET_NAME(x19), > + REG_OFFSET_NAME(x20), > + REG_OFFSET_NAME(x21), > + REG_OFFSET_NAME(x22), > + REG_OFFSET_NAME(x23), > + REG_OFFSET_NAME(x24), > + REG_OFFSET_NAME(x25), > + REG_OFFSET_NAME(x26), > + REG_OFFSET_NAME(x27), > + REG_OFFSET_NAME(x28), > + REG_OFFSET_NAME(x29), > + REG_OFFSET_NAME(x30), Does this interact badly with perf tools, which expect to pass "lr" for x30? (see tools/perf/arch/arm64/include/perf_regs.h). Will
On 08/11/15 13:31, Will Deacon wrote: > Hi David, > > On Tue, Aug 11, 2015 at 01:52:38AM +0100, David Long wrote: >> From: "David A. Long" <dave.long@linaro.org> >> >> Add HAVE_REGS_AND_STACK_ACCESS_API feature for arm64. >> >> Signed-off-by: David A. Long <dave.long@linaro.org> >> --- >> arch/arm64/Kconfig | 1 + >> arch/arm64/include/asm/ptrace.h | 25 +++++++++++++ >> arch/arm64/kernel/ptrace.c | 77 +++++++++++++++++++++++++++++++++++++++++ >> 3 files changed, 103 insertions(+) >> >> diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig >> index 318175f..ef5d726 100644 >> --- a/arch/arm64/Kconfig >> +++ b/arch/arm64/Kconfig >> @@ -70,6 +70,7 @@ config ARM64 >> select HAVE_PERF_EVENTS >> select HAVE_PERF_REGS >> select HAVE_PERF_USER_STACK_DUMP >> + select HAVE_REGS_AND_STACK_ACCESS_API >> select HAVE_RCU_TABLE_FREE >> select HAVE_SYSCALL_TRACEPOINTS >> select IRQ_DOMAIN >> diff --git a/arch/arm64/include/asm/ptrace.h b/arch/arm64/include/asm/ptrace.h >> index d6dd9fd..8f440e9 100644 >> --- a/arch/arm64/include/asm/ptrace.h >> +++ b/arch/arm64/include/asm/ptrace.h >> @@ -118,6 +118,8 @@ struct pt_regs { >> u64 syscallno; >> }; >> >> +#define MAX_REG_OFFSET (sizeof(struct user_pt_regs) - sizeof(u64)) > > Can you not use offset_of(struct user_pt_regs, pstate) here? Yes, "offsetof" actually though. I've just made that change. >> + >> #define arch_has_single_step() (1) >> >> #ifdef CONFIG_COMPAT >> @@ -146,6 +148,29 @@ struct pt_regs { >> #define user_stack_pointer(regs) \ >> (!compat_user_mode(regs) ? (regs)->sp : (regs)->compat_sp) >> >> +/** >> + * regs_get_register() - get register value from its offset >> + * @regs: pt_regs from which register value is gotten >> + * @offset: offset number of the register. >> + * >> + * regs_get_register returns the value of a register whose offset from @regs. >> + * The @offset is the offset of the register in struct pt_regs. >> + * If @offset is bigger than MAX_REG_OFFSET, this returns 0. >> + */ >> +static inline u64 regs_get_register(struct pt_regs *regs, >> + unsigned int offset) >> +{ >> + if (unlikely(offset > MAX_REG_OFFSET)) >> + return 0; >> + return *(u64 *)((u64)regs + offset); >> +} > > Is this guaranteed only to be called on kernel-mode regs, or do we need > to deal with compat tasks too? If I understand the question I think it's fine that it only deals with kernel-mode registers. The implemenation is functionally similar to the other five architectures that implement it. >> + >> +/* Valid only for Kernel mode traps. */ >> +static inline unsigned long kernel_stack_pointer(struct pt_regs *regs) >> +{ >> + return regs->sp; >> +} >> + >> static inline unsigned long regs_return_value(struct pt_regs *regs) >> { >> return regs->regs[0]; >> diff --git a/arch/arm64/kernel/ptrace.c b/arch/arm64/kernel/ptrace.c >> index d882b83..f6199a5 100644 >> --- a/arch/arm64/kernel/ptrace.c >> +++ b/arch/arm64/kernel/ptrace.c >> @@ -48,6 +48,83 @@ >> #define CREATE_TRACE_POINTS >> #include <trace/events/syscalls.h> >> >> +#define ARM_pstate pstate >> +#define ARM_pc pc >> +#define ARM_sp sp >> +#define ARM_x30 regs[30] >> +#define ARM_x29 regs[29] >> +#define ARM_x28 regs[28] >> +#define ARM_x27 regs[27] >> +#define ARM_x26 regs[26] >> +#define ARM_x25 regs[25] >> +#define ARM_x24 regs[24] >> +#define ARM_x23 regs[23] >> +#define ARM_x22 regs[22] >> +#define ARM_x21 regs[21] >> +#define ARM_x20 regs[20] >> +#define ARM_x19 regs[19] >> +#define ARM_x18 regs[18] >> +#define ARM_x17 regs[17] >> +#define ARM_x16 regs[16] >> +#define ARM_x15 regs[15] >> +#define ARM_x14 regs[14] >> +#define ARM_x13 regs[13] >> +#define ARM_x12 regs[12] >> +#define ARM_x11 regs[11] >> +#define ARM_x10 regs[10] >> +#define ARM_x9 regs[9] >> +#define ARM_x8 regs[8] >> +#define ARM_x7 regs[7] >> +#define ARM_x6 regs[6] >> +#define ARM_x5 regs[5] >> +#define ARM_x4 regs[4] >> +#define ARM_x3 regs[3] >> +#define ARM_x2 regs[2] >> +#define ARM_x1 regs[1] >> +#define ARM_x0 regs[0] > > I've said it before, but I really don't like these macros. I'd rather > rework the following REG_OFFSET_NAME to be GPR_OFFSET_NAME which could > prefix the "x" in the name field. OK, I've ripped that out and replaced REG_OFFSET_NAME with GPR_OFFSET_NAME, for the numbered registers. I'm using REGS_OFFSET_NAME (defined for all architectures in my earlier cleanup patch) for the non-numbered registers. > >> + >> +#define REG_OFFSET_NAME(r) \ >> + {.name = #r, .offset = offsetof(struct pt_regs, ARM_##r)} >> +#define REG_OFFSET_END {.name = NULL, .offset = 0} >> + >> +const struct pt_regs_offset regs_offset_table[] = { >> + REG_OFFSET_NAME(x0), >> + REG_OFFSET_NAME(x1), >> + REG_OFFSET_NAME(x2), >> + REG_OFFSET_NAME(x3), >> + REG_OFFSET_NAME(x4), >> + REG_OFFSET_NAME(x5), >> + REG_OFFSET_NAME(x6), >> + REG_OFFSET_NAME(x7), >> + REG_OFFSET_NAME(x8), >> + REG_OFFSET_NAME(x9), >> + REG_OFFSET_NAME(x10), >> + REG_OFFSET_NAME(x11), >> + REG_OFFSET_NAME(x12), >> + REG_OFFSET_NAME(x13), >> + REG_OFFSET_NAME(x14), >> + REG_OFFSET_NAME(x15), >> + REG_OFFSET_NAME(x16), >> + REG_OFFSET_NAME(x17), >> + REG_OFFSET_NAME(x18), >> + REG_OFFSET_NAME(x19), >> + REG_OFFSET_NAME(x20), >> + REG_OFFSET_NAME(x21), >> + REG_OFFSET_NAME(x22), >> + REG_OFFSET_NAME(x23), >> + REG_OFFSET_NAME(x24), >> + REG_OFFSET_NAME(x25), >> + REG_OFFSET_NAME(x26), >> + REG_OFFSET_NAME(x27), >> + REG_OFFSET_NAME(x28), >> + REG_OFFSET_NAME(x29), >> + REG_OFFSET_NAME(x30), > > Does this interact badly with perf tools, which expect to pass "lr" for > x30? (see tools/perf/arch/arm64/include/perf_regs.h). > Possibly, I can test that when I'm back from my short vacation this week. The lr/x30 thing seems to be a recurring issue. Perhaps it is best simply to add a reundant entry for x30 as "lr". It's simple enough to do, although just slightly ugly looking as it would have to be done without a macro. Would one ever use "x31" in place of "sp"? Conversions in the other direction would have to use one or the other of course. > Will > -dl
Hi David, On Thu, Aug 13, 2015 at 04:50:40AM +0100, David Long wrote: > On 08/11/15 13:31, Will Deacon wrote: > > On Tue, Aug 11, 2015 at 01:52:38AM +0100, David Long wrote: > >> + REG_OFFSET_NAME(x30), > > > > Does this interact badly with perf tools, which expect to pass "lr" for > > x30? (see tools/perf/arch/arm64/include/perf_regs.h). > > > > Possibly, I can test that when I'm back from my short vacation this > week. The lr/x30 thing seems to be a recurring issue. Perhaps it is > best simply to add a reundant entry for x30 as "lr". It's simple enough > to do, although just slightly ugly looking as it would have to be done > without a macro. Would one ever use "x31" in place of "sp"? No; "sp" should always be "sp". Let me know how you get on with perf. I couldn't quite tie the two ends together, but it does look like it expects "lr" to work. Will
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index 318175f..ef5d726 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -70,6 +70,7 @@ config ARM64 select HAVE_PERF_EVENTS select HAVE_PERF_REGS select HAVE_PERF_USER_STACK_DUMP + select HAVE_REGS_AND_STACK_ACCESS_API select HAVE_RCU_TABLE_FREE select HAVE_SYSCALL_TRACEPOINTS select IRQ_DOMAIN diff --git a/arch/arm64/include/asm/ptrace.h b/arch/arm64/include/asm/ptrace.h index d6dd9fd..8f440e9 100644 --- a/arch/arm64/include/asm/ptrace.h +++ b/arch/arm64/include/asm/ptrace.h @@ -118,6 +118,8 @@ struct pt_regs { u64 syscallno; }; +#define MAX_REG_OFFSET (sizeof(struct user_pt_regs) - sizeof(u64)) + #define arch_has_single_step() (1) #ifdef CONFIG_COMPAT @@ -146,6 +148,29 @@ struct pt_regs { #define user_stack_pointer(regs) \ (!compat_user_mode(regs) ? (regs)->sp : (regs)->compat_sp) +/** + * regs_get_register() - get register value from its offset + * @regs: pt_regs from which register value is gotten + * @offset: offset number of the register. + * + * regs_get_register returns the value of a register whose offset from @regs. + * The @offset is the offset of the register in struct pt_regs. + * If @offset is bigger than MAX_REG_OFFSET, this returns 0. + */ +static inline u64 regs_get_register(struct pt_regs *regs, + unsigned int offset) +{ + if (unlikely(offset > MAX_REG_OFFSET)) + return 0; + return *(u64 *)((u64)regs + offset); +} + +/* Valid only for Kernel mode traps. */ +static inline unsigned long kernel_stack_pointer(struct pt_regs *regs) +{ + return regs->sp; +} + static inline unsigned long regs_return_value(struct pt_regs *regs) { return regs->regs[0]; diff --git a/arch/arm64/kernel/ptrace.c b/arch/arm64/kernel/ptrace.c index d882b83..f6199a5 100644 --- a/arch/arm64/kernel/ptrace.c +++ b/arch/arm64/kernel/ptrace.c @@ -48,6 +48,83 @@ #define CREATE_TRACE_POINTS #include <trace/events/syscalls.h> +#define ARM_pstate pstate +#define ARM_pc pc +#define ARM_sp sp +#define ARM_x30 regs[30] +#define ARM_x29 regs[29] +#define ARM_x28 regs[28] +#define ARM_x27 regs[27] +#define ARM_x26 regs[26] +#define ARM_x25 regs[25] +#define ARM_x24 regs[24] +#define ARM_x23 regs[23] +#define ARM_x22 regs[22] +#define ARM_x21 regs[21] +#define ARM_x20 regs[20] +#define ARM_x19 regs[19] +#define ARM_x18 regs[18] +#define ARM_x17 regs[17] +#define ARM_x16 regs[16] +#define ARM_x15 regs[15] +#define ARM_x14 regs[14] +#define ARM_x13 regs[13] +#define ARM_x12 regs[12] +#define ARM_x11 regs[11] +#define ARM_x10 regs[10] +#define ARM_x9 regs[9] +#define ARM_x8 regs[8] +#define ARM_x7 regs[7] +#define ARM_x6 regs[6] +#define ARM_x5 regs[5] +#define ARM_x4 regs[4] +#define ARM_x3 regs[3] +#define ARM_x2 regs[2] +#define ARM_x1 regs[1] +#define ARM_x0 regs[0] + +#define REG_OFFSET_NAME(r) \ + {.name = #r, .offset = offsetof(struct pt_regs, ARM_##r)} +#define REG_OFFSET_END {.name = NULL, .offset = 0} + +const struct pt_regs_offset regs_offset_table[] = { + REG_OFFSET_NAME(x0), + REG_OFFSET_NAME(x1), + REG_OFFSET_NAME(x2), + REG_OFFSET_NAME(x3), + REG_OFFSET_NAME(x4), + REG_OFFSET_NAME(x5), + REG_OFFSET_NAME(x6), + REG_OFFSET_NAME(x7), + REG_OFFSET_NAME(x8), + REG_OFFSET_NAME(x9), + REG_OFFSET_NAME(x10), + REG_OFFSET_NAME(x11), + REG_OFFSET_NAME(x12), + REG_OFFSET_NAME(x13), + REG_OFFSET_NAME(x14), + REG_OFFSET_NAME(x15), + REG_OFFSET_NAME(x16), + REG_OFFSET_NAME(x17), + REG_OFFSET_NAME(x18), + REG_OFFSET_NAME(x19), + REG_OFFSET_NAME(x20), + REG_OFFSET_NAME(x21), + REG_OFFSET_NAME(x22), + REG_OFFSET_NAME(x23), + REG_OFFSET_NAME(x24), + REG_OFFSET_NAME(x25), + REG_OFFSET_NAME(x26), + REG_OFFSET_NAME(x27), + REG_OFFSET_NAME(x28), + REG_OFFSET_NAME(x29), + REG_OFFSET_NAME(x30), + REG_OFFSET_NAME(sp), + REG_OFFSET_NAME(pc), + REG_OFFSET_NAME(pstate), + REG_OFFSET_END, +}; + /* * TODO: does not yet catch signals sent when the child dies. * in exit.c or in signal.c.