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Sun, 2 Nov 2025 11:54:41 +0000 (GMT) From: Mukesh Kumar Chaurasiya To: maddy@linux.ibm.com, mpe@ellerman.id.au, npiggin@gmail.com, christophe.leroy@csgroup.eu, oleg@redhat.com, kees@kernel.org, luto@amacapital.net, wad@chromium.org, mchauras@linux.ibm.com, thuth@redhat.com, sshegde@linux.ibm.com, akpm@linux-foundation.org, macro@orcam.me.uk, ldv@strace.io, deller@gmx.de, charlie@rivosinc.com, bigeasy@linutronix.de, segher@kernel.crashing.org, thomas.weissschuh@linutronix.de, menglong8.dong@gmail.com, ankur.a.arora@oracle.com, peterz@infradead.org, namcao@linutronix.de, tglx@linutronix.de, kan.liang@linux.intel.com, mingo@kernel.org, atrajeev@linux.vnet.ibm.com, mark.barnett@arm.com, coltonlewis@google.com, rppt@kernel.org, linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org Subject: [PATCH 7/8] powerpc: Enable IRQ generic entry/exit path. Date: Sun, 2 Nov 2025 17:23:57 +0530 Message-ID: <20251102115358.1744304-8-mkchauras@linux.ibm.com> X-Mailer: git-send-email 2.51.0 In-Reply-To: <20251102115358.1744304-1-mkchauras@linux.ibm.com> References: <20251102115358.1744304-1-mkchauras@linux.ibm.com> X-Mailing-List: linuxppc-dev@lists.ozlabs.org List-Id: List-Help: List-Owner: List-Post: List-Archive: , List-Subscribe: , , List-Unsubscribe: Precedence: list MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-TM-AS-GCONF: 00 X-Authority-Analysis: v=2.4 cv=StmdKfO0 c=1 sm=1 tr=0 ts=6907468c cx=c_pps a=AfN7/Ok6k8XGzOShvHwTGQ==:117 a=AfN7/Ok6k8XGzOShvHwTGQ==:17 a=IkcTkHD0fZMA:10 a=6UeiqGixMTsA:10 a=VkNPw1HP01LnGYTKEx00:22 a=VnNF1IyMAAAA:8 a=NIz8WlYnyIp8l4wp2tMA:9 a=3ZKOabzyN94A:10 a=QEXdDO2ut3YA:10 a=nl4s5V0KI7Kw-pW0DWrs:22 a=pHzHmUro8NiASowvMSCR:22 a=xoEH_sTeL_Rfw54TyV31:22 X-Proofpoint-ORIG-GUID: f7WDx-Fzn7rfAprxjn8zNWOFUTSoPK3W X-Proofpoint-Spam-Details-Enc: AW1haW4tMjUxMTAxMDAxOCBTYWx0ZWRfX0/MxHdy8E+cJ 5J8wVt3Tu0sTMXCNB9+mkTGjXTNBBTP02i8D1MldoZvwVmOtGp3O8Jiyr45tlJmLINtntZONbN4 8Gx4gNItq+W+d2LeA7misYd1mveyBjdjYLKYWb1Agbj7QtoZYjZnzy699jNx/4ywDy96SNcx0Vp C7k4dCxMASCXyQtUGFm1wQwU/FtXRFpQQbjMg+cGalgMec5N5WT+52O3QIRksSoaTWZyoBadaTY l2B5K00OhiLv/T/QKr8783uddHT3ZWcmX9XtPCHTtsmhHK/g4q4Snin2nfke+ItaYVnMEMDQTJM Iwq+V+pcX0Vrh7wCWJlQz3xBf/0NpM+0J19Gpz0bImcKV+cspg/HzSesHlwbrvuXdtWjSk3t5TT MCMZmjW7/kLzjYyZGuPO0Z63BUmfYA== X-Proofpoint-GUID: XdTZaIYnkAOL6YAqlwfIEL-UPOpARN99 X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1121,Hydra:6.1.9,FMLib:17.12.100.49 definitions=2025-11-02_02,2025-10-29_03,2025-10-01_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 spamscore=0 suspectscore=0 phishscore=0 impostorscore=0 priorityscore=1501 malwarescore=0 clxscore=1015 adultscore=0 bulkscore=0 lowpriorityscore=0 classifier=typeunknown authscore=0 authtc= authcc= route=outbound adjust=0 reason=mlx scancount=1 engine=8.19.0-2510240000 definitions=main-2511010018 From: Mukesh Kumar Chaurasiya Enable the generic IRQ entry/exit infrastructure on PowerPC by selecting GENERIC_IRQ_ENTRY and integrating the architecture-specific interrupt handlers with the generic entry/exit APIs. This change replaces PowerPC’s local interrupt entry/exit handling with calls to the generic irqentry_* helpers, aligning the architecture with the common kernel entry model. The macros that define interrupt, async, and NMI handlers are updated to use irqentry_enter()/irqentry_exit() and irqentry_nmi_enter()/irqentry_nmi_exit() where applicable. Key updates include: - Select GENERIC_IRQ_ENTRY in Kconfig. - Replace interrupt_enter/exit_prepare() with arch_interrupt_* helpers. - Integrate irqentry_enter()/exit() in standard and async interrupt paths. - Integrate irqentry_nmi_enter()/exit() in NMI handlers. - Remove redundant irq_enter()/irq_exit() calls now handled generically. - Use irqentry_exit_cond_resched() for preemption checks. This change establishes the necessary wiring for PowerPC to use the generic IRQ entry/exit framework while maintaining existing semantics. Signed-off-by: Mukesh Kumar Chaurasiya --- arch/powerpc/Kconfig | 1 + arch/powerpc/include/asm/entry-common.h | 66 +--- arch/powerpc/include/asm/interrupt.h | 499 +++--------------------- arch/powerpc/kernel/interrupt.c | 13 +- 4 files changed, 74 insertions(+), 505 deletions(-) diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig index e24f4d88885a..b0c602c3bbe1 100644 --- a/arch/powerpc/Kconfig +++ b/arch/powerpc/Kconfig @@ -206,6 +206,7 @@ config PPC select GENERIC_GETTIMEOFDAY select GENERIC_IDLE_POLL_SETUP select GENERIC_IOREMAP + select GENERIC_IRQ_ENTRY select GENERIC_IRQ_SHOW select GENERIC_IRQ_SHOW_LEVEL select GENERIC_PCI_IOMAP if PCI diff --git a/arch/powerpc/include/asm/entry-common.h b/arch/powerpc/include/asm/entry-common.h index e8bde4c67eaf..e2ae7416dee1 100644 --- a/arch/powerpc/include/asm/entry-common.h +++ b/arch/powerpc/include/asm/entry-common.h @@ -257,6 +257,17 @@ static inline void arch_interrupt_enter_prepare(struct pt_regs *regs) */ static inline void arch_interrupt_exit_prepare(struct pt_regs *regs) { + if (user_mode(regs)) { + BUG_ON(regs_is_unrecoverable(regs)); + BUG_ON(regs_irqs_disabled(regs)); + /* + * We don't need to restore AMR on the way back to userspace for KUAP. + * AMR can only have been unlocked if we interrupted the kernel. + */ + kuap_assert_locked(); + + local_irq_disable(); + } } static inline void arch_interrupt_async_enter_prepare(struct pt_regs *regs) @@ -275,7 +286,6 @@ static inline void arch_interrupt_async_enter_prepare(struct pt_regs *regs) !test_thread_local_flags(_TLF_RUNLATCH)) __ppc64_runlatch_on(); #endif - irq_enter(); } static inline void arch_interrupt_async_exit_prepare(struct pt_regs *regs) @@ -288,7 +298,6 @@ static inline void arch_interrupt_async_exit_prepare(struct pt_regs *regs) */ nap_adjust_return(regs); - irq_exit(); arch_interrupt_exit_prepare(regs); } @@ -354,59 +363,11 @@ static inline void arch_interrupt_nmi_enter_prepare(struct pt_regs *regs, this_cpu_set_ftrace_enabled(0); } #endif - - /* If data relocations are enabled, it's safe to use nmi_enter() */ - if (mfmsr() & MSR_DR) { - nmi_enter(); - return; - } - - /* - * But do not use nmi_enter() for pseries hash guest taking a real-mode - * NMI because not everything it touches is within the RMA limit. - */ - if (IS_ENABLED(CONFIG_PPC_BOOK3S_64) && - firmware_has_feature(FW_FEATURE_LPAR) && - !radix_enabled()) - return; - - /* - * Likewise, don't use it if we have some form of instrumentation (like - * KASAN shadow) that is not safe to access in real mode (even on radix) - */ - if (IS_ENABLED(CONFIG_KASAN)) - return; - - /* - * Likewise, do not use it in real mode if percpu first chunk is not - * embedded. With CONFIG_NEED_PER_CPU_PAGE_FIRST_CHUNK enabled there - * are chances where percpu allocation can come from vmalloc area. - */ - if (percpu_first_chunk_is_paged) - return; - - /* Otherwise, it should be safe to call it */ - nmi_enter(); } static inline void arch_interrupt_nmi_exit_prepare(struct pt_regs *regs, struct interrupt_nmi_state *state) { - if (mfmsr() & MSR_DR) { - // nmi_exit if relocations are on - nmi_exit(); - } else if (IS_ENABLED(CONFIG_PPC_BOOK3S_64) && - firmware_has_feature(FW_FEATURE_LPAR) && - !radix_enabled()) { - // no nmi_exit for a pseries hash guest taking a real mode exception - } else if (IS_ENABLED(CONFIG_KASAN)) { - // no nmi_exit for KASAN in real mode - } else if (percpu_first_chunk_is_paged) { - // no nmi_exit if percpu first chunk is not embedded - } else { - nmi_exit(); - } - /* * nmi does not call nap_adjust_return because nmi should not create * new work to do (must use irq_work for that). @@ -435,6 +396,8 @@ static inline void arch_interrupt_nmi_exit_prepare(struct pt_regs *regs, static __always_inline void arch_enter_from_user_mode(struct pt_regs *regs) { + kuap_lock(); + if (IS_ENABLED(CONFIG_PPC_IRQ_SOFT_MASK_DEBUG)) BUG_ON(irq_soft_mask_return() != IRQS_ALL_DISABLED); @@ -467,11 +430,8 @@ static __always_inline void arch_enter_from_user_mode(struct pt_regs *regs) } else #endif kuap_assert_locked(); - booke_restore_dbcr0(); - account_cpu_user_entry(); - account_stolen_time(); /* diff --git a/arch/powerpc/include/asm/interrupt.h b/arch/powerpc/include/asm/interrupt.h index 77ff8e33f8cd..e2376de85370 100644 --- a/arch/powerpc/include/asm/interrupt.h +++ b/arch/powerpc/include/asm/interrupt.h @@ -66,433 +66,10 @@ #ifndef __ASSEMBLER__ -#include -#include #include /* for show_regs */ +#include -#include -#include -#include #include -#include - -#ifdef CONFIG_PPC_IRQ_SOFT_MASK_DEBUG -/* - * WARN/BUG is handled with a program interrupt so minimise checks here to - * avoid recursion and maximise the chance of getting the first oops handled. - */ -#define INT_SOFT_MASK_BUG_ON(regs, cond) \ -do { \ - if ((user_mode(regs) || (TRAP(regs) != INTERRUPT_PROGRAM))) \ - BUG_ON(cond); \ -} while (0) -#else -#define INT_SOFT_MASK_BUG_ON(regs, cond) -#endif - -#ifdef CONFIG_PPC_BOOK3S_64 -extern char __end_soft_masked[]; -bool search_kernel_soft_mask_table(unsigned long addr); -unsigned long search_kernel_restart_table(unsigned long addr); - -DECLARE_STATIC_KEY_FALSE(interrupt_exit_not_reentrant); - -static inline bool is_implicit_soft_masked(struct pt_regs *regs) -{ - if (user_mode(regs)) - return false; - - if (regs->nip >= (unsigned long)__end_soft_masked) - return false; - - return search_kernel_soft_mask_table(regs->nip); -} - -static inline void srr_regs_clobbered(void) -{ - local_paca->srr_valid = 0; - local_paca->hsrr_valid = 0; -} -#else -static inline unsigned long search_kernel_restart_table(unsigned long addr) -{ - return 0; -} - -static inline bool is_implicit_soft_masked(struct pt_regs *regs) -{ - return false; -} - -static inline void srr_regs_clobbered(void) -{ -} -#endif - -static inline void nap_adjust_return(struct pt_regs *regs) -{ -#ifdef CONFIG_PPC_970_NAP - if (unlikely(test_thread_local_flags(_TLF_NAPPING))) { - /* Can avoid a test-and-clear because NMIs do not call this */ - clear_thread_local_flags(_TLF_NAPPING); - regs_set_return_ip(regs, (unsigned long)power4_idle_nap_return); - } -#endif -} - -static inline void booke_load_dbcr0(void) -{ -#ifdef CONFIG_PPC_ADV_DEBUG_REGS - unsigned long dbcr0 = current->thread.debug.dbcr0; - - if (likely(!(dbcr0 & DBCR0_IDM))) - return; - - /* - * Check to see if the dbcr0 register is set up to debug. - * Use the internal debug mode bit to do this. - */ - mtmsr(mfmsr() & ~MSR_DE); - if (IS_ENABLED(CONFIG_PPC32)) { - isync(); - global_dbcr0[smp_processor_id()] = mfspr(SPRN_DBCR0); - } - mtspr(SPRN_DBCR0, dbcr0); - mtspr(SPRN_DBSR, -1); -#endif -} - -static inline void booke_restore_dbcr0(void) -{ -#ifdef CONFIG_PPC_ADV_DEBUG_REGS - unsigned long dbcr0 = current->thread.debug.dbcr0; - - if (IS_ENABLED(CONFIG_PPC32) && unlikely(dbcr0 & DBCR0_IDM)) { - mtspr(SPRN_DBSR, -1); - mtspr(SPRN_DBCR0, global_dbcr0[smp_processor_id()]); - } -#endif -} - -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 = TRAP(regs); - // EE in HV mode sets HSRRs like 0xea0 - if (cpu_has_feature(CPU_FTR_HVMODE) && trap == INTERRUPT_EXTERNAL) - trap = 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 = &local_paca->hsrr_valid; - if (!READ_ONCE(*validp)) - return; - - srr0 = mfspr(SPRN_HSRR0); - srr1 = mfspr(SPRN_HSRR1); - h = "H"; - - break; - default: - validp = &local_paca->srr_valid; - if (!READ_ONCE(*validp)) - return; - - srr0 = mfspr(SPRN_SRR0); - srr1 = mfspr(SPRN_SRR1); - h = ""; - break; - } - - if (srr0 == regs->nip && srr1 == 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 = true); - pr_warn("%sSRR0 was: %lx should be: %lx\n", h, srr0, regs->nip); - pr_warn("%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 - irq_soft_mask_set(IRQS_ALL_DISABLED); - - /* - * If the interrupt was taken with HARD_DIS clear, then enable MSR[EE]. - * Asynchronous interrupts get here with HARD_DIS set (see below), so - * this enables MSR[EE] for synchronous interrupts. IRQs remain - * soft-masked. The interrupt handler may later call - * interrupt_cond_local_irq_enable() to achieve a regular process - * context. - */ - if (!(local_paca->irq_happened & PACA_IRQ_HARD_DIS)) { - INT_SOFT_MASK_BUG_ON(regs, !(regs->msr & MSR_EE)); - __hard_irq_enable(); - } else { - __hard_RI_enable(); - } - /* Enable MSR[RI] early, to support kernel SLB and hash faults */ -#endif - - if (!regs_irqs_disabled(regs)) - trace_hardirqs_off(); - - if (user_mode(regs)) { - kuap_lock(); - CT_WARN_ON(ct_state() != CT_STATE_USER); - user_exit_irqoff(); - - account_cpu_user_entry(); - account_stolen_time(); - } else { - kuap_save_and_lock(regs); - /* - * CT_WARN_ON comes here via program_check_exception, - * so avoid recursion. - */ - if (TRAP(regs) != INTERRUPT_PROGRAM) - CT_WARN_ON(ct_state() != CT_STATE_KERNEL && - ct_state() != CT_STATE_IDLE); - INT_SOFT_MASK_BUG_ON(regs, is_implicit_soft_masked(regs)); - INT_SOFT_MASK_BUG_ON(regs, regs_irqs_disabled(regs) && - search_kernel_restart_table(regs->nip)); - } - INT_SOFT_MASK_BUG_ON(regs, !regs_irqs_disabled(regs) && - !(regs->msr & MSR_EE)); - - booke_restore_dbcr0(); -} - -/* - * Care should be taken to note that interrupt_exit_prepare and - * interrupt_async_exit_prepare do not necessarily return immediately to - * regs context (e.g., if regs is usermode, we don't necessarily return to - * user mode). Other interrupts might be taken between here and return, - * context switch / preemption may occur in the exit path after this, or a - * signal may be delivered, etc. - * - * The real interrupt exit code is platform specific, e.g., - * interrupt_exit_user_prepare / interrupt_exit_kernel_prepare for 64s. - * - * However interrupt_nmi_exit_prepare does return directly to regs, because - * NMIs do not do "exit work" or replay soft-masked interrupts. - */ -static inline void interrupt_exit_prepare(struct pt_regs *regs) -{ -} - -static inline void interrupt_async_enter_prepare(struct pt_regs *regs) -{ -#ifdef CONFIG_PPC64 - /* Ensure interrupt_enter_prepare does not enable MSR[EE] */ - local_paca->irq_happened |= PACA_IRQ_HARD_DIS; -#endif - interrupt_enter_prepare(regs); -#ifdef CONFIG_PPC_BOOK3S_64 - /* - * RI=1 is set by interrupt_enter_prepare, so this thread flags access - * has to come afterward (it can cause SLB faults). - */ - if (cpu_has_feature(CPU_FTR_CTRL) && - !test_thread_local_flags(_TLF_RUNLATCH)) - __ppc64_runlatch_on(); -#endif - irq_enter(); -} - -static inline void interrupt_async_exit_prepare(struct pt_regs *regs) -{ - /* - * Adjust at exit so the main handler sees the true NIA. This must - * come before irq_exit() because irq_exit can enable interrupts, and - * if another interrupt is taken before nap_adjust_return has run - * here, then that interrupt would return directly to idle nap return. - */ - nap_adjust_return(regs); - - irq_exit(); - interrupt_exit_prepare(regs); -} - -struct interrupt_nmi_state { -#ifdef CONFIG_PPC64 - u8 irq_soft_mask; - u8 irq_happened; - u8 ftrace_enabled; - u64 softe; -#endif -}; - -static inline bool nmi_disables_ftrace(struct pt_regs *regs) -{ - /* Allow DEC and PMI to be traced when they are soft-NMI */ - if (IS_ENABLED(CONFIG_PPC_BOOK3S_64)) { - if (TRAP(regs) == INTERRUPT_DECREMENTER) - return false; - if (TRAP(regs) == INTERRUPT_PERFMON) - return false; - } - if (IS_ENABLED(CONFIG_PPC_BOOK3E_64)) { - if (TRAP(regs) == INTERRUPT_PERFMON) - return false; - } - - return true; -} - -static inline void interrupt_nmi_enter_prepare(struct pt_regs *regs, struct interrupt_nmi_state *state) -{ -#ifdef CONFIG_PPC64 - state->irq_soft_mask = local_paca->irq_soft_mask; - state->irq_happened = local_paca->irq_happened; - state->softe = regs->softe; - - /* - * Set IRQS_ALL_DISABLED unconditionally so irqs_disabled() does - * the right thing, and set IRQ_HARD_DIS. We do not want to reconcile - * because that goes through irq tracing which we don't want in NMI. - */ - local_paca->irq_soft_mask = IRQS_ALL_DISABLED; - local_paca->irq_happened |= PACA_IRQ_HARD_DIS; - - if (!(regs->msr & MSR_EE) || is_implicit_soft_masked(regs)) { - /* - * Adjust regs->softe to be soft-masked if it had not been - * reconcied (e.g., interrupt entry with MSR[EE]=0 but softe - * not yet set disabled), or if it was in an implicit soft - * masked state. This makes regs_irqs_disabled(regs) - * behave as expected. - */ - regs->softe = IRQS_ALL_DISABLED; - } - - __hard_RI_enable(); - - /* Don't do any per-CPU operations until interrupt state is fixed */ - - if (nmi_disables_ftrace(regs)) { - state->ftrace_enabled = this_cpu_get_ftrace_enabled(); - this_cpu_set_ftrace_enabled(0); - } -#endif - - /* If data relocations are enabled, it's safe to use nmi_enter() */ - if (mfmsr() & MSR_DR) { - nmi_enter(); - return; - } - - /* - * But do not use nmi_enter() for pseries hash guest taking a real-mode - * NMI because not everything it touches is within the RMA limit. - */ - if (IS_ENABLED(CONFIG_PPC_BOOK3S_64) && - firmware_has_feature(FW_FEATURE_LPAR) && - !radix_enabled()) - return; - - /* - * Likewise, don't use it if we have some form of instrumentation (like - * KASAN shadow) that is not safe to access in real mode (even on radix) - */ - if (IS_ENABLED(CONFIG_KASAN)) - return; - - /* - * Likewise, do not use it in real mode if percpu first chunk is not - * embedded. With CONFIG_NEED_PER_CPU_PAGE_FIRST_CHUNK enabled there - * are chances where percpu allocation can come from vmalloc area. - */ - if (percpu_first_chunk_is_paged) - return; - - /* Otherwise, it should be safe to call it */ - nmi_enter(); -} - -static inline void interrupt_nmi_exit_prepare(struct pt_regs *regs, struct interrupt_nmi_state *state) -{ - if (mfmsr() & MSR_DR) { - // nmi_exit if relocations are on - nmi_exit(); - } else if (IS_ENABLED(CONFIG_PPC_BOOK3S_64) && - firmware_has_feature(FW_FEATURE_LPAR) && - !radix_enabled()) { - // no nmi_exit for a pseries hash guest taking a real mode exception - } else if (IS_ENABLED(CONFIG_KASAN)) { - // no nmi_exit for KASAN in real mode - } else if (percpu_first_chunk_is_paged) { - // no nmi_exit if percpu first chunk is not embedded - } else { - nmi_exit(); - } - - /* - * nmi does not call nap_adjust_return because nmi should not create - * new work to do (must use irq_work for that). - */ - -#ifdef CONFIG_PPC64 -#ifdef CONFIG_PPC_BOOK3S - if (regs_irqs_disabled(regs)) { - unsigned long rst = search_kernel_restart_table(regs->nip); - if (rst) - regs_set_return_ip(regs, rst); - } -#endif - - if (nmi_disables_ftrace(regs)) - this_cpu_set_ftrace_enabled(state->ftrace_enabled); - - /* Check we didn't change the pending interrupt mask. */ - WARN_ON_ONCE((state->irq_happened | PACA_IRQ_HARD_DIS) != local_paca->irq_happened); - regs->softe = state->softe; - local_paca->irq_happened = state->irq_happened; - local_paca->irq_soft_mask = state->irq_soft_mask; -#endif -} /* * Don't use noinstr here like x86, but rather add NOKPROBE_SYMBOL to each @@ -574,11 +151,14 @@ static __always_inline void ____##func(struct pt_regs *regs); \ \ interrupt_handler void func(struct pt_regs *regs) \ { \ - interrupt_enter_prepare(regs); \ - \ + irqentry_state_t state; \ + arch_interrupt_enter_prepare(regs); \ + state = irqentry_enter(regs); \ + instrumentation_begin(); \ ____##func (regs); \ - \ - interrupt_exit_prepare(regs); \ + instrumentation_end(); \ + arch_interrupt_exit_prepare(regs); \ + irqentry_exit(regs, state); \ } \ NOKPROBE_SYMBOL(func); \ \ @@ -608,12 +188,15 @@ static __always_inline long ____##func(struct pt_regs *regs); \ interrupt_handler long func(struct pt_regs *regs) \ { \ long ret; \ + irqentry_state_t state; \ \ - interrupt_enter_prepare(regs); \ - \ + arch_interrupt_enter_prepare(regs); \ + state = irqentry_enter(regs); \ + instrumentation_begin(); \ ret = ____##func (regs); \ - \ - interrupt_exit_prepare(regs); \ + instrumentation_end(); \ + arch_interrupt_exit_prepare(regs); \ + irqentry_exit(regs, state); \ \ return ret; \ } \ @@ -642,11 +225,16 @@ static __always_inline void ____##func(struct pt_regs *regs); \ \ interrupt_handler void func(struct pt_regs *regs) \ { \ - interrupt_async_enter_prepare(regs); \ - \ + irqentry_state_t state; \ + arch_interrupt_async_enter_prepare(regs); \ + state = irqentry_enter(regs); \ + instrumentation_begin(); \ + irq_enter_rcu(); \ ____##func (regs); \ - \ - interrupt_async_exit_prepare(regs); \ + irq_exit_rcu(); \ + instrumentation_end(); \ + arch_interrupt_async_exit_prepare(regs); \ + irqentry_exit(regs, state); \ } \ NOKPROBE_SYMBOL(func); \ \ @@ -676,14 +264,43 @@ ____##func(struct pt_regs *regs); \ \ interrupt_handler long func(struct pt_regs *regs) \ { \ - struct interrupt_nmi_state state; \ + irqentry_state_t state; \ + struct interrupt_nmi_state nmi_state; \ long ret; \ \ - interrupt_nmi_enter_prepare(regs, &state); \ - \ + arch_interrupt_nmi_enter_prepare(regs, &nmi_state); \ + if (mfmsr() & MSR_DR) { \ + /* nmi_entry if relocations are on */ \ + state = irqentry_nmi_enter(regs); \ + } else if (IS_ENABLED(CONFIG_PPC_BOOK3S_64) && \ + firmware_has_feature(FW_FEATURE_LPAR) && \ + !radix_enabled()) { \ + /* no nmi_entry for a pseries hash guest \ + * taking a real mode exception */ \ + } else if (IS_ENABLED(CONFIG_KASAN)) { \ + /* no nmi_entry for KASAN in real mode */ \ + } else if (percpu_first_chunk_is_paged) { \ + /* no nmi_entry if percpu first chunk is not embedded */\ + } else { \ + state = irqentry_nmi_enter(regs); \ + } \ ret = ____##func (regs); \ - \ - interrupt_nmi_exit_prepare(regs, &state); \ + arch_interrupt_nmi_exit_prepare(regs, &nmi_state); \ + if (mfmsr() & MSR_DR) { \ + /* nmi_exit if relocations are on */ \ + irqentry_nmi_exit(regs, state); \ + } else if (IS_ENABLED(CONFIG_PPC_BOOK3S_64) && \ + firmware_has_feature(FW_FEATURE_LPAR) && \ + !radix_enabled()) { \ + /* no nmi_exit for a pseries hash guest \ + * taking a real mode exception */ \ + } else if (IS_ENABLED(CONFIG_KASAN)) { \ + /* no nmi_exit for KASAN in real mode */ \ + } else if (percpu_first_chunk_is_paged) { \ + /* no nmi_exit if percpu first chunk is not embedded */ \ + } else { \ + irqentry_nmi_exit(regs, state); \ + } \ \ return ret; \ } \ diff --git a/arch/powerpc/kernel/interrupt.c b/arch/powerpc/kernel/interrupt.c index f53d432f6087..7f67f0b9d627 100644 --- a/arch/powerpc/kernel/interrupt.c +++ b/arch/powerpc/kernel/interrupt.c @@ -24,10 +24,6 @@ unsigned long global_dbcr0[NR_CPUS]; #endif -#if defined(CONFIG_PREEMPT_DYNAMIC) -DEFINE_STATIC_KEY_TRUE(sk_dynamic_irqentry_exit_cond_resched); -#endif - #ifdef CONFIG_PPC_BOOK3S_64 DEFINE_STATIC_KEY_FALSE(interrupt_exit_not_reentrant); static inline bool exit_must_hard_disable(void) @@ -297,13 +293,8 @@ notrace unsigned long interrupt_exit_kernel_prepare(struct pt_regs *regs) /* Returning to a kernel context with local irqs enabled. */ WARN_ON_ONCE(!(regs->msr & MSR_EE)); again: - if (need_irq_preemption()) { - /* Return to preemptible kernel context */ - if (unlikely(read_thread_flags() & _TIF_NEED_RESCHED)) { - if (preempt_count() == 0) - preempt_schedule_irq(); - } - } + if (need_irq_preemption()) + irqentry_exit_cond_resched(); check_return_regs_valid(regs); -- 2.51.0