From 806c0e6e7e97adc17389c8dc1f52d4736f49299b Mon Sep 17 00:00:00 2001 From: Christophe Leroy Date: Mon, 23 Aug 2021 08:24:21 +0000 Subject: [PATCH] powerpc: Refactor verification of MSR_RI 40x and BOOKE don't have MSR_RI therefore all tests involving MSR_RI may be problematic on those plateforms. Create helpers to check or set MSR_RI in regs, and use them in common code. Signed-off-by: Christophe Leroy Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/c2fb93708196734f4176dda334aaa3055f213b89.1629707037.git.christophe.leroy@csgroup.eu --- arch/powerpc/include/asm/ptrace.h | 23 +++++++++++++++++++++++ arch/powerpc/kernel/interrupt.c | 9 +++------ arch/powerpc/kernel/traps.c | 8 ++++---- arch/powerpc/mm/book3s64/slb.c | 2 +- arch/powerpc/platforms/embedded6xx/holly.c | 2 +- arch/powerpc/platforms/embedded6xx/mpc7448_hpc2.c | 2 +- arch/powerpc/platforms/pasemi/idle.c | 2 +- arch/powerpc/platforms/powernv/opal.c | 2 +- arch/powerpc/platforms/pseries/ras.c | 2 +- arch/powerpc/sysdev/fsl_rio.c | 2 +- arch/powerpc/xmon/xmon.c | 16 +++------------- 11 files changed, 40 insertions(+), 30 deletions(-) diff --git a/arch/powerpc/include/asm/ptrace.h b/arch/powerpc/include/asm/ptrace.h index 5114ddb..f9c235c 100644 --- a/arch/powerpc/include/asm/ptrace.h +++ b/arch/powerpc/include/asm/ptrace.h @@ -22,6 +22,7 @@ #include #include #include +#include #ifndef __ASSEMBLY__ struct pt_regs @@ -272,6 +273,28 @@ static inline void regs_set_return_value(struct pt_regs *regs, unsigned long rc) regs->gpr[3] = rc; } +static inline bool cpu_has_msr_ri(void) +{ + return !IS_ENABLED(CONFIG_BOOKE) && !IS_ENABLED(CONFIG_40x); +} + +static inline bool regs_is_unrecoverable(struct pt_regs *regs) +{ + return unlikely(cpu_has_msr_ri() && !(regs->msr & MSR_RI)); +} + +static inline void regs_set_recoverable(struct pt_regs *regs) +{ + if (cpu_has_msr_ri()) + regs_set_return_msr(regs, regs->msr | MSR_RI); +} + +static inline void regs_set_unrecoverable(struct pt_regs *regs) +{ + if (cpu_has_msr_ri()) + regs_set_return_msr(regs, regs->msr & ~MSR_RI); +} + #define arch_has_single_step() (1) #define arch_has_block_step() (true) #define ARCH_HAS_USER_SINGLE_STEP_REPORT diff --git a/arch/powerpc/kernel/interrupt.c b/arch/powerpc/kernel/interrupt.c index 531f0a1..a73f3f7 100644 --- a/arch/powerpc/kernel/interrupt.c +++ b/arch/powerpc/kernel/interrupt.c @@ -92,8 +92,7 @@ notrace long system_call_exception(long r3, long r4, long r5, CT_WARN_ON(ct_state() == CONTEXT_KERNEL); user_exit_irqoff(); - if (!IS_ENABLED(CONFIG_BOOKE) && !IS_ENABLED(CONFIG_40x)) - BUG_ON(!(regs->msr & MSR_RI)); + BUG_ON(regs_is_unrecoverable(regs)); BUG_ON(!(regs->msr & MSR_PR)); BUG_ON(arch_irq_disabled_regs(regs)); @@ -462,8 +461,7 @@ notrace unsigned long interrupt_exit_user_prepare(struct pt_regs *regs) { unsigned long ret; - if (!IS_ENABLED(CONFIG_BOOKE) && !IS_ENABLED(CONFIG_40x)) - BUG_ON(!(regs->msr & MSR_RI)); + BUG_ON(regs_is_unrecoverable(regs)); BUG_ON(arch_irq_disabled_regs(regs)); CT_WARN_ON(ct_state() == CONTEXT_USER); @@ -494,8 +492,7 @@ notrace unsigned long interrupt_exit_kernel_prepare(struct pt_regs *regs) bool stack_store = current_thread_info()->flags & _TIF_EMULATE_STACK_STORE; - if (!IS_ENABLED(CONFIG_BOOKE) && !IS_ENABLED(CONFIG_40x) && - unlikely(!(regs->msr & MSR_RI))) + if (regs_is_unrecoverable(regs)) unrecoverable_exception(regs); /* * CT_WARN_ON comes here via program_check_exception, diff --git a/arch/powerpc/kernel/traps.c b/arch/powerpc/kernel/traps.c index 5463d20..3a344f5 100644 --- a/arch/powerpc/kernel/traps.c +++ b/arch/powerpc/kernel/traps.c @@ -428,7 +428,7 @@ void hv_nmi_check_nonrecoverable(struct pt_regs *regs) return; nonrecoverable: - regs_set_return_msr(regs, regs->msr & ~MSR_RI); + regs_set_unrecoverable(regs); #endif } DEFINE_INTERRUPT_HANDLER_NMI(system_reset_exception) @@ -498,7 +498,7 @@ out: die("Unrecoverable nested System Reset", regs, SIGABRT); #endif /* Must die if the interrupt is not recoverable */ - if (!(regs->msr & MSR_RI)) { + if (regs_is_unrecoverable(regs)) { /* For the reason explained in die_mce, nmi_exit before die */ nmi_exit(); die("Unrecoverable System Reset", regs, SIGABRT); @@ -550,7 +550,7 @@ static inline int check_io_access(struct pt_regs *regs) printk(KERN_DEBUG "%s bad port %lx at %p\n", (*nip & 0x100)? "OUT to": "IN from", regs->gpr[rb] - _IO_BASE, nip); - regs_set_return_msr(regs, regs->msr | MSR_RI); + regs_set_recoverable(regs); regs_set_return_ip(regs, extable_fixup(entry)); return 1; } @@ -840,7 +840,7 @@ DEFINE_INTERRUPT_HANDLER_NMI(machine_check_exception) bail: /* Must die if the interrupt is not recoverable */ - if (!(regs->msr & MSR_RI)) + if (regs_is_unrecoverable(regs)) die_mce("Unrecoverable Machine check", regs, SIGBUS); #ifdef CONFIG_PPC_BOOK3S_64 diff --git a/arch/powerpc/mm/book3s64/slb.c b/arch/powerpc/mm/book3s64/slb.c index c91bd85..f0037bc 100644 --- a/arch/powerpc/mm/book3s64/slb.c +++ b/arch/powerpc/mm/book3s64/slb.c @@ -822,7 +822,7 @@ DEFINE_INTERRUPT_HANDLER_RAW(do_slb_fault) /* IRQs are not reconciled here, so can't check irqs_disabled */ VM_WARN_ON(mfmsr() & MSR_EE); - if (unlikely(!(regs->msr & MSR_RI))) + if (regs_is_unrecoverable(regs)) return -EINVAL; /* diff --git a/arch/powerpc/platforms/embedded6xx/holly.c b/arch/powerpc/platforms/embedded6xx/holly.c index 85521b3..7a85b11 100644 --- a/arch/powerpc/platforms/embedded6xx/holly.c +++ b/arch/powerpc/platforms/embedded6xx/holly.c @@ -251,7 +251,7 @@ static int ppc750_machine_check_exception(struct pt_regs *regs) /* Are we prepared to handle this fault */ if ((entry = search_exception_tables(regs->nip)) != NULL) { tsi108_clear_pci_cfg_error(); - regs_set_return_msr(regs, regs->msr | MSR_RI); + regs_set_recoverable(regs); regs_set_return_ip(regs, extable_fixup(entry)); return 1; } diff --git a/arch/powerpc/platforms/embedded6xx/mpc7448_hpc2.c b/arch/powerpc/platforms/embedded6xx/mpc7448_hpc2.c index d8da6a4..9eb9abb 100644 --- a/arch/powerpc/platforms/embedded6xx/mpc7448_hpc2.c +++ b/arch/powerpc/platforms/embedded6xx/mpc7448_hpc2.c @@ -173,7 +173,7 @@ static int mpc7448_machine_check_exception(struct pt_regs *regs) /* Are we prepared to handle this fault */ if ((entry = search_exception_tables(regs->nip)) != NULL) { tsi108_clear_pci_cfg_error(); - regs_set_return_msr(regs, regs->msr | MSR_RI); + regs_set_recoverable(regs); regs_set_return_ip(regs, extable_fixup(entry)); return 1; } diff --git a/arch/powerpc/platforms/pasemi/idle.c b/arch/powerpc/platforms/pasemi/idle.c index 9b88e3c..2a5b842 100644 --- a/arch/powerpc/platforms/pasemi/idle.c +++ b/arch/powerpc/platforms/pasemi/idle.c @@ -58,7 +58,7 @@ static int pasemi_system_reset_exception(struct pt_regs *regs) restore_astate(hard_smp_processor_id()); /* everything handled */ - regs_set_return_msr(regs, regs->msr | MSR_RI); + regs_set_recoverable(regs); return 1; } diff --git a/arch/powerpc/platforms/powernv/opal.c b/arch/powerpc/platforms/powernv/opal.c index 2835376..e9d1851 100644 --- a/arch/powerpc/platforms/powernv/opal.c +++ b/arch/powerpc/platforms/powernv/opal.c @@ -588,7 +588,7 @@ static int opal_recover_mce(struct pt_regs *regs, { int recovered = 0; - if (!(regs->msr & MSR_RI)) { + if (regs_is_unrecoverable(regs)) { /* If MSR_RI isn't set, we cannot recover */ pr_err("Machine check interrupt unrecoverable: MSR(RI=0)\n"); recovered = 0; diff --git a/arch/powerpc/platforms/pseries/ras.c b/arch/powerpc/platforms/pseries/ras.c index 167f2e1..56092dc 100644 --- a/arch/powerpc/platforms/pseries/ras.c +++ b/arch/powerpc/platforms/pseries/ras.c @@ -783,7 +783,7 @@ static int recover_mce(struct pt_regs *regs, struct machine_check_event *evt) { int recovered = 0; - if (!(regs->msr & MSR_RI)) { + if (regs_is_unrecoverable(regs)) { /* If MSR_RI isn't set, we cannot recover */ pr_err("Machine check interrupt unrecoverable: MSR(RI=0)\n"); recovered = 0; diff --git a/arch/powerpc/sysdev/fsl_rio.c b/arch/powerpc/sysdev/fsl_rio.c index 5a95b8e..ff7906b 100644 --- a/arch/powerpc/sysdev/fsl_rio.c +++ b/arch/powerpc/sysdev/fsl_rio.c @@ -108,7 +108,7 @@ int fsl_rio_mcheck_exception(struct pt_regs *regs) __func__); out_be32((u32 *)(rio_regs_win + RIO_LTLEDCSR), 0); - regs_set_return_msr(regs, regs->msr | MSR_RI); + regs_set_recoverable(regs); regs_set_return_ip(regs, extable_fixup(entry)); return 1; } diff --git a/arch/powerpc/xmon/xmon.c b/arch/powerpc/xmon/xmon.c index ead460b..dd8241c 100644 --- a/arch/powerpc/xmon/xmon.c +++ b/arch/powerpc/xmon/xmon.c @@ -482,16 +482,6 @@ static inline void get_output_lock(void) {} static inline void release_output_lock(void) {} #endif -static inline int unrecoverable_excp(struct pt_regs *regs) -{ -#if defined(CONFIG_4xx) || defined(CONFIG_PPC_BOOK3E) - /* We have no MSR_RI bit on 4xx or Book3e, so we simply return false */ - return 0; -#else - return ((regs->msr & MSR_RI) == 0); -#endif -} - static void xmon_touch_watchdogs(void) { touch_softlockup_watchdog_sync(); @@ -565,7 +555,7 @@ static int xmon_core(struct pt_regs *regs, volatile int fromipi) bp = NULL; if ((regs->msr & (MSR_IR|MSR_PR|MSR_64BIT)) == (MSR_IR|MSR_64BIT)) bp = at_breakpoint(regs->nip); - if (bp || unrecoverable_excp(regs)) + if (bp || regs_is_unrecoverable(regs)) fromipi = 0; if (!fromipi) { @@ -577,7 +567,7 @@ static int xmon_core(struct pt_regs *regs, volatile int fromipi) cpu, BP_NUM(bp)); xmon_print_symbol(regs->nip, " ", ")\n"); } - if (unrecoverable_excp(regs)) + if (regs_is_unrecoverable(regs)) printf("WARNING: exception is not recoverable, " "can't continue\n"); release_output_lock(); @@ -693,7 +683,7 @@ static int xmon_core(struct pt_regs *regs, volatile int fromipi) printf("Stopped at breakpoint %tx (", BP_NUM(bp)); xmon_print_symbol(regs->nip, " ", ")\n"); } - if (unrecoverable_excp(regs)) + if (regs_is_unrecoverable(regs)) printf("WARNING: exception is not recoverable, " "can't continue\n"); remove_bpts(); -- 2.7.4