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charset="utf-8" Introducing following functions for syscall exit - arch_exit_to_user_mode_work - arch_exit_to_user_mode_work_prepare Signed-off-by: Mukesh Kumar Chaurasiya --- arch/powerpc/include/asm/entry-common.h | 51 +++++++++++++++ arch/powerpc/include/asm/interrupt.h | 82 +++++++++++++++++++++++++ arch/powerpc/kernel/interrupt.c | 81 ------------------------ arch/powerpc/kernel/signal.c | 14 +++++ 4 files changed, 147 insertions(+), 81 deletions(-) diff --git a/arch/powerpc/include/asm/entry-common.h b/arch/powerpc/include= /asm/entry-common.h index 804f6d019ec95..04db70afdd820 100644 --- a/arch/powerpc/include/asm/entry-common.h +++ b/arch/powerpc/include/asm/entry-common.h @@ -8,8 +8,14 @@ #include #include #include +#include #include =20 +/* + * flags for paca->generic_fw_flags + */ +#define GFW_RESTORE_ALL 0x01 + static __always_inline void arch_enter_from_user_mode(struct pt_regs *regs) { if (IS_ENABLED(CONFIG_PPC_IRQ_SOFT_MASK_DEBUG)) @@ -101,7 +107,52 @@ static __always_inline void arch_enter_from_user_mode(= struct pt_regs *regs) } #endif // CONFIG_PPC_TRANSACTIONAL_MEM } + #define arch_enter_from_user_mode arch_enter_from_user_mode =20 +static inline void arch_exit_to_user_mode_prepare(struct pt_regs *regs, + unsigned long ti_work) +{ + unsigned long mathflags; + + if (IS_ENABLED(CONFIG_PPC_BOOK3S_64) && IS_ENABLED(CONFIG_PPC_FPU)) { + if (IS_ENABLED(CONFIG_PPC_TRANSACTIONAL_MEM) && + unlikely((ti_work & _TIF_RESTORE_TM))) { + restore_tm_state(regs); + } else { + mathflags =3D MSR_FP; + + if (cpu_has_feature(CPU_FTR_VSX)) + mathflags |=3D MSR_VEC | MSR_VSX; + else if (cpu_has_feature(CPU_FTR_ALTIVEC)) + mathflags |=3D MSR_VEC; + + /* + * If userspace MSR has all available FP bits set, + * then they are live and no need to restore. If not, + * it means the regs were given up and restore_math + * may decide to restore them (to avoid taking an FP + * fault). + */ + if ((regs->msr & mathflags) !=3D mathflags) + restore_math(regs); + } + } + + check_return_regs_valid(regs); +#ifdef CONFIG_PPC_TRANSACTIONAL_MEM + local_paca->tm_scratch =3D regs->msr; +#endif +} +#define arch_exit_to_user_mode_prepare arch_exit_to_user_mode_prepare + +static __always_inline void arch_exit_to_user_mode(void) +{ + booke_load_dbcr0(); + + account_cpu_user_exit(); +} +#define arch_exit_to_user_mode arch_exit_to_user_mode + #endif /* CONFIG_GENERIC_ENTRY */ #endif /* _ASM_PPC_ENTRY_COMMON_H */ diff --git a/arch/powerpc/include/asm/interrupt.h b/arch/powerpc/include/as= m/interrupt.h index 6edf064a0fea2..c6ab286a723f2 100644 --- a/arch/powerpc/include/asm/interrupt.h +++ b/arch/powerpc/include/asm/interrupt.h @@ -68,6 +68,8 @@ =20 #include #include +#include /* for show_regs */ + #include #include #include @@ -173,6 +175,86 @@ static inline void booke_restore_dbcr0(void) #endif } =20 +static inline void check_return_regs_valid(struct pt_regs *regs) +{ +#ifdef CONFIG_PPC_BOOK3S_64 + unsigned long trap, srr0, srr1; + static bool warned; + u8 *validp; + char *h; + + if (trap_is_scv(regs)) + return; + + trap =3D TRAP(regs); + // EE in HV mode sets HSRRs like 0xea0 + if (cpu_has_feature(CPU_FTR_HVMODE) && trap =3D=3D INTERRUPT_EXTERNAL) + trap =3D 0xea0; + + switch (trap) { + case 0x980: + case INTERRUPT_H_DATA_STORAGE: + case 0xe20: + case 0xe40: + case INTERRUPT_HMI: + case 0xe80: + case 0xea0: + case INTERRUPT_H_FAC_UNAVAIL: + case 0x1200: + case 0x1500: + case 0x1600: + case 0x1800: + validp =3D &local_paca->hsrr_valid; + if (!READ_ONCE(*validp)) + return; + + srr0 =3D mfspr(SPRN_HSRR0); + srr1 =3D mfspr(SPRN_HSRR1); + h =3D "H"; + + break; + default: + validp =3D &local_paca->srr_valid; + if (!READ_ONCE(*validp)) + return; + + srr0 =3D mfspr(SPRN_SRR0); + srr1 =3D mfspr(SPRN_SRR1); + h =3D ""; + break; + } + + if (srr0 =3D=3D regs->nip && srr1 =3D=3D regs->msr) + return; + + /* + * A NMI / soft-NMI interrupt may have come in after we found + * srr_valid and before the SRRs are loaded. The interrupt then + * comes in and clobbers SRRs and clears srr_valid. Then we load + * the SRRs here and test them above and find they don't match. + * + * Test validity again after that, to catch such false positives. + * + * This test in general will have some window for false negatives + * and may not catch and fix all such cases if an NMI comes in + * later and clobbers SRRs without clearing srr_valid, but hopefully + * such things will get caught most of the time, statistically + * enough to be able to get a warning out. + */ + if (!READ_ONCE(*validp)) + return; + + if (!data_race(warned)) { + data_race(warned =3D true); + printk("%sSRR0 was: %lx should be: %lx\n", h, srr0, regs->nip); + printk("%sSRR1 was: %lx should be: %lx\n", h, srr1, regs->msr); + show_regs(regs); + } + + WRITE_ONCE(*validp, 0); /* fixup */ +#endif +} + static inline void interrupt_enter_prepare(struct pt_regs *regs) { #ifdef CONFIG_PPC64 diff --git a/arch/powerpc/kernel/interrupt.c b/arch/powerpc/kernel/interrup= t.c index 44afc65e0e0e0..7f31f3fb9c1d8 100644 --- a/arch/powerpc/kernel/interrupt.c +++ b/arch/powerpc/kernel/interrupt.c @@ -4,7 +4,6 @@ #include #include #include -#include /* for show_regs */ =20 #include #include @@ -74,86 +73,6 @@ static notrace __always_inline bool prep_irq_for_enabled= _exit(bool restartable) return true; } =20 -static notrace void check_return_regs_valid(struct pt_regs *regs) -{ -#ifdef CONFIG_PPC_BOOK3S_64 - unsigned long trap, srr0, srr1; - static bool warned; - u8 *validp; - char *h; - - if (trap_is_scv(regs)) - return; - - trap =3D TRAP(regs); - // EE in HV mode sets HSRRs like 0xea0 - if (cpu_has_feature(CPU_FTR_HVMODE) && trap =3D=3D INTERRUPT_EXTERNAL) - trap =3D 0xea0; - - switch (trap) { - case 0x980: - case INTERRUPT_H_DATA_STORAGE: - case 0xe20: - case 0xe40: - case INTERRUPT_HMI: - case 0xe80: - case 0xea0: - case INTERRUPT_H_FAC_UNAVAIL: - case 0x1200: - case 0x1500: - case 0x1600: - case 0x1800: - validp =3D &local_paca->hsrr_valid; - if (!READ_ONCE(*validp)) - return; - - srr0 =3D mfspr(SPRN_HSRR0); - srr1 =3D mfspr(SPRN_HSRR1); - h =3D "H"; - - break; - default: - validp =3D &local_paca->srr_valid; - if (!READ_ONCE(*validp)) - return; - - srr0 =3D mfspr(SPRN_SRR0); - srr1 =3D mfspr(SPRN_SRR1); - h =3D ""; - break; - } - - if (srr0 =3D=3D regs->nip && srr1 =3D=3D regs->msr) - return; - - /* - * A NMI / soft-NMI interrupt may have come in after we found - * srr_valid and before the SRRs are loaded. The interrupt then - * comes in and clobbers SRRs and clears srr_valid. Then we load - * the SRRs here and test them above and find they don't match. - * - * Test validity again after that, to catch such false positives. - * - * This test in general will have some window for false negatives - * and may not catch and fix all such cases if an NMI comes in - * later and clobbers SRRs without clearing srr_valid, but hopefully - * such things will get caught most of the time, statistically - * enough to be able to get a warning out. - */ - if (!READ_ONCE(*validp)) - return; - - if (!data_race(warned)) { - data_race(warned =3D true); - printk("%sSRR0 was: %lx should be: %lx\n", h, srr0, regs->nip); - printk("%sSRR1 was: %lx should be: %lx\n", h, srr1, regs->msr); - show_regs(regs); - } - - WRITE_ONCE(*validp, 0); /* fixup */ -#endif -} - static notrace unsigned long interrupt_exit_user_prepare_main(unsigned long ret, struct pt_regs *regs) { diff --git a/arch/powerpc/kernel/signal.c b/arch/powerpc/kernel/signal.c index aa17e62f37547..719930cf4ae1f 100644 --- a/arch/powerpc/kernel/signal.c +++ b/arch/powerpc/kernel/signal.c @@ -22,6 +22,11 @@ =20 #include "signal.h" =20 +/* This will be removed */ +#ifdef CONFIG_GENERIC_ENTRY +#include +#endif /* CONFIG_GENERIC_ENTRY */ + #ifdef CONFIG_VSX unsigned long copy_fpr_to_user(void __user *to, struct task_struct *task) @@ -368,3 +373,12 @@ void signal_fault(struct task_struct *tsk, struct pt_r= egs *regs, printk_ratelimited(regs->msr & MSR_64BIT ? fm64 : fm32, tsk->comm, task_pid_nr(tsk), where, ptr, regs->nip, regs->link); } + +#ifdef CONFIG_GENERIC_ENTRY +void arch_do_signal_or_restart(struct pt_regs *regs) +{ + BUG_ON(regs !=3D current->thread.regs); + local_paca->generic_fw_flags |=3D GFW_RESTORE_ALL; + do_signal(current); +} +#endif /* CONFIG_GENERIC_ENTRY */ --=20 2.49.0