| Message ID | 20170817072347.19990-2-nicolas.pitre@linaro.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Hi Nicolas, I have successfully tested your set of patches on cortex-M7 STM32 MCU. On 08/17/2017 09:23 AM, Nicolas Pitre wrote: > When there is no dedicated register to hold the tp value and no MMU > to provide a fixed address kuser helper entry point, all that is > left as fallback is a syscall. > > Signed-off-by: Nicolas Pitre <nico@linaro.org> Tested-by: Vincent Abriou <vincent.abriou@st.com> BR Vincent > --- > arch/arm/include/uapi/asm/unistd.h | 1 + > arch/arm/kernel/traps.c | 3 +++ > 2 files changed, 4 insertions(+) > > diff --git a/arch/arm/include/uapi/asm/unistd.h b/arch/arm/include/uapi/asm/unistd.h > index 28bd456494..575b25fc29 100644 > --- a/arch/arm/include/uapi/asm/unistd.h > +++ b/arch/arm/include/uapi/asm/unistd.h > @@ -35,5 +35,6 @@ > #define __ARM_NR_usr26 (__ARM_NR_BASE+3) > #define __ARM_NR_usr32 (__ARM_NR_BASE+4) > #define __ARM_NR_set_tls (__ARM_NR_BASE+5) > +#define __ARM_NR_get_tls (__ARM_NR_BASE+6) > > #endif /* _UAPI__ASM_ARM_UNISTD_H */ > diff --git a/arch/arm/kernel/traps.c b/arch/arm/kernel/traps.c > index 948c648fea..43c0560f7b 100644 > --- a/arch/arm/kernel/traps.c > +++ b/arch/arm/kernel/traps.c > @@ -647,6 +647,9 @@ asmlinkage int arm_syscall(int no, struct pt_regs *regs) > set_tls(regs->ARM_r0); > return 0; > > + case NR(get_tls): > + return current_thread_info()->tp_value[0]; > + > default: > /* Calls 9f00xx..9f07ff are defined to return -ENOSYS > if not implemented, rather than raising SIGILL. This >
diff --git a/arch/arm/include/uapi/asm/unistd.h b/arch/arm/include/uapi/asm/unistd.h index 28bd456494..575b25fc29 100644 --- a/arch/arm/include/uapi/asm/unistd.h +++ b/arch/arm/include/uapi/asm/unistd.h @@ -35,5 +35,6 @@ #define __ARM_NR_usr26 (__ARM_NR_BASE+3) #define __ARM_NR_usr32 (__ARM_NR_BASE+4) #define __ARM_NR_set_tls (__ARM_NR_BASE+5) +#define __ARM_NR_get_tls (__ARM_NR_BASE+6) #endif /* _UAPI__ASM_ARM_UNISTD_H */ diff --git a/arch/arm/kernel/traps.c b/arch/arm/kernel/traps.c index 948c648fea..43c0560f7b 100644 --- a/arch/arm/kernel/traps.c +++ b/arch/arm/kernel/traps.c @@ -647,6 +647,9 @@ asmlinkage int arm_syscall(int no, struct pt_regs *regs) set_tls(regs->ARM_r0); return 0; + case NR(get_tls): + return current_thread_info()->tp_value[0]; + default: /* Calls 9f00xx..9f07ff are defined to return -ENOSYS if not implemented, rather than raising SIGILL. This
When there is no dedicated register to hold the tp value and no MMU to provide a fixed address kuser helper entry point, all that is left as fallback is a syscall. Signed-off-by: Nicolas Pitre <nico@linaro.org> --- arch/arm/include/uapi/asm/unistd.h | 1 + arch/arm/kernel/traps.c | 3 +++ 2 files changed, 4 insertions(+)