diff options
| -rw-r--r-- | Documentation/kernel-parameters.txt | 6 | ||||
| -rw-r--r-- | arch/powerpc/include/asm/reg.h | 9 | ||||
| -rw-r--r-- | arch/powerpc/include/asm/switch_to.h | 24 | ||||
| -rw-r--r-- | arch/powerpc/kernel/process.c | 17 |
4 files changed, 49 insertions, 7 deletions
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index 742f69d18fc8..8978c26cacdd 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -2978,6 +2978,12 @@ bytes respectively. Such letter suffixes can also be entirely omitted. may be specified. Format: <port>,<port>.... + ppc_strict_facility_enable + [PPC] This option catches any kernel floating point, + Altivec, VSX and SPE outside of regions specifically + allowed (eg kernel_enable_fpu()/kernel_disable_fpu()). + There is some performance impact when enabling this. + print-fatal-signals= [KNL] debug: print fatal signals diff --git a/arch/powerpc/include/asm/reg.h b/arch/powerpc/include/asm/reg.h index 987dac090244..eb2986e60c50 100644 --- a/arch/powerpc/include/asm/reg.h +++ b/arch/powerpc/include/asm/reg.h @@ -1214,6 +1214,15 @@ static inline void mtmsr_isync(unsigned long val) : "r" ((unsigned long)(v)) \ : "memory") +extern void msr_check_and_set(unsigned long bits); +extern bool strict_msr_control; +extern void __msr_check_and_clear(unsigned long bits); +static inline void msr_check_and_clear(unsigned long bits) +{ + if (strict_msr_control) + __msr_check_and_clear(bits); +} + static inline unsigned long mfvtb (void) { #ifdef CONFIG_PPC_BOOK3S_64 diff --git a/arch/powerpc/include/asm/switch_to.h b/arch/powerpc/include/asm/switch_to.h index 438502f59550..9414dcb180d6 100644 --- a/arch/powerpc/include/asm/switch_to.h +++ b/arch/powerpc/include/asm/switch_to.h @@ -4,6 +4,8 @@ #ifndef _ASM_POWERPC_SWITCH_TO_H #define _ASM_POWERPC_SWITCH_TO_H +#include <asm/reg.h> + struct thread_struct; struct task_struct; struct pt_regs; @@ -26,15 +28,15 @@ extern void enable_kernel_spe(void); extern void load_up_spe(struct task_struct *); extern void switch_booke_debug_regs(struct debug_reg *new_debug); -static inline void disable_kernel_fp(void) { } -static inline void disable_kernel_altivec(void) { } -static inline void disable_kernel_spe(void) { } -static inline void disable_kernel_vsx(void) { } - #ifdef CONFIG_PPC_FPU extern void flush_fp_to_thread(struct task_struct *); extern void giveup_fpu(struct task_struct *); extern void __giveup_fpu(struct task_struct *); +static inline void disable_kernel_fp(void) +{ + msr_check_and_clear(MSR_FP); +} + #else static inline void flush_fp_to_thread(struct task_struct *t) { } static inline void giveup_fpu(struct task_struct *t) { } @@ -45,6 +47,10 @@ static inline void __giveup_fpu(struct task_struct *t) { } extern void flush_altivec_to_thread(struct task_struct *); extern void giveup_altivec(struct task_struct *); extern void __giveup_altivec(struct task_struct *); +static inline void disable_kernel_altivec(void) +{ + msr_check_and_clear(MSR_VEC); +} #else static inline void flush_altivec_to_thread(struct task_struct *t) { } static inline void giveup_altivec(struct task_struct *t) { } @@ -53,6 +59,10 @@ static inline void __giveup_altivec(struct task_struct *t) { } #ifdef CONFIG_VSX extern void flush_vsx_to_thread(struct task_struct *); +static inline void disable_kernel_vsx(void) +{ + msr_check_and_clear(MSR_FP|MSR_VEC|MSR_VSX); +} #else static inline void flush_vsx_to_thread(struct task_struct *t) { @@ -63,6 +73,10 @@ static inline void flush_vsx_to_thread(struct task_struct *t) extern void flush_spe_to_thread(struct task_struct *); extern void giveup_spe(struct task_struct *); extern void __giveup_spe(struct task_struct *); +static inline void disable_kernel_spe(void) +{ + msr_check_and_clear(MSR_SPE); +} #else static inline void flush_spe_to_thread(struct task_struct *t) { } static inline void giveup_spe(struct task_struct *t) { } diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c index 5cdd35c0b026..1eafceefeac9 100644 --- a/arch/powerpc/kernel/process.c +++ b/arch/powerpc/kernel/process.c @@ -87,7 +87,19 @@ static void check_if_tm_restore_required(struct task_struct *tsk) static inline void check_if_tm_restore_required(struct task_struct *tsk) { } #endif /* CONFIG_PPC_TRANSACTIONAL_MEM */ -static void msr_check_and_set(unsigned long bits) +bool strict_msr_control; +EXPORT_SYMBOL(strict_msr_control); + +static int __init enable_strict_msr_control(char *str) +{ + strict_msr_control = true; + pr_info("Enabling strict facility control\n"); + + return 0; +} +early_param("ppc_strict_facility_enable", enable_strict_msr_control); + +void msr_check_and_set(unsigned long bits) { unsigned long oldmsr = mfmsr(); unsigned long newmsr; @@ -103,7 +115,7 @@ static void msr_check_and_set(unsigned long bits) mtmsr_isync(newmsr); } -static void msr_check_and_clear(unsigned long bits) +void __msr_check_and_clear(unsigned long bits) { unsigned long oldmsr = mfmsr(); unsigned long newmsr; @@ -118,6 +130,7 @@ static void msr_check_and_clear(unsigned long bits) if (oldmsr != newmsr) mtmsr_isync(newmsr); } +EXPORT_SYMBOL(__msr_check_and_clear); #ifdef CONFIG_PPC_FPU void giveup_fpu(struct task_struct *tsk) |
