diff options
Diffstat (limited to 'arch/powerpc/kernel/interrupt_64.S')
| -rw-r--r-- | arch/powerpc/kernel/interrupt_64.S | 772 |
1 files changed, 772 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/interrupt_64.S b/arch/powerpc/kernel/interrupt_64.S new file mode 100644 index 0000000000..bd863702d8 --- /dev/null +++ b/arch/powerpc/kernel/interrupt_64.S @@ -0,0 +1,772 @@ +#include <asm/asm-offsets.h> +#include <asm/bug.h> +#ifdef CONFIG_PPC_BOOK3S +#include <asm/exception-64s.h> +#else +#include <asm/exception-64e.h> +#endif +#include <asm/feature-fixups.h> +#include <asm/head-64.h> +#include <asm/hw_irq.h> +#include <asm/kup.h> +#include <asm/mmu.h> +#include <asm/ppc_asm.h> +#include <asm/ptrace.h> + + .align 7 + +.macro DEBUG_SRR_VALID srr +#ifdef CONFIG_PPC_RFI_SRR_DEBUG + .ifc \srr,srr + mfspr r11,SPRN_SRR0 + ld r12,_NIP(r1) + clrrdi r11,r11,2 + clrrdi r12,r12,2 +100: tdne r11,r12 + EMIT_WARN_ENTRY 100b,__FILE__,__LINE__,(BUGFLAG_WARNING | BUGFLAG_ONCE) + mfspr r11,SPRN_SRR1 + ld r12,_MSR(r1) +100: tdne r11,r12 + EMIT_WARN_ENTRY 100b,__FILE__,__LINE__,(BUGFLAG_WARNING | BUGFLAG_ONCE) + .else + mfspr r11,SPRN_HSRR0 + ld r12,_NIP(r1) + clrrdi r11,r11,2 + clrrdi r12,r12,2 +100: tdne r11,r12 + EMIT_WARN_ENTRY 100b,__FILE__,__LINE__,(BUGFLAG_WARNING | BUGFLAG_ONCE) + mfspr r11,SPRN_HSRR1 + ld r12,_MSR(r1) +100: tdne r11,r12 + EMIT_WARN_ENTRY 100b,__FILE__,__LINE__,(BUGFLAG_WARNING | BUGFLAG_ONCE) + .endif +#endif +.endm + +#ifdef CONFIG_PPC_BOOK3S +.macro system_call_vectored name trapnr + .globl system_call_vectored_\name +system_call_vectored_\name: +_ASM_NOKPROBE_SYMBOL(system_call_vectored_\name) + SCV_INTERRUPT_TO_KERNEL + mr r10,r1 + ld r1,PACAKSAVE(r13) + std r10,0(r1) + std r11,_NIP(r1) + std r12,_MSR(r1) + std r0,GPR0(r1) + std r10,GPR1(r1) + std r2,GPR2(r1) + LOAD_PACA_TOC() + mfcr r12 + li r11,0 + /* Save syscall parameters in r3-r8 */ + SAVE_GPRS(3, 8, r1) + /* Zero r9-r12, this should only be required when restoring all GPRs */ + std r11,GPR9(r1) + std r11,GPR10(r1) + std r11,GPR11(r1) + std r11,GPR12(r1) + std r9,GPR13(r1) + SAVE_NVGPRS(r1) + std r11,_XER(r1) + std r11,_LINK(r1) + std r11,_CTR(r1) + + li r11,\trapnr + std r11,_TRAP(r1) + std r12,_CCR(r1) + std r3,ORIG_GPR3(r1) + LOAD_REG_IMMEDIATE(r11, STACK_FRAME_REGS_MARKER) + std r11,STACK_INT_FRAME_MARKER(r1) /* "regs" marker */ + /* Calling convention has r3 = regs, r4 = orig r0 */ + addi r3,r1,STACK_INT_FRAME_REGS + mr r4,r0 + +BEGIN_FTR_SECTION + HMT_MEDIUM +END_FTR_SECTION_IFSET(CPU_FTR_HAS_PPR) + + /* + * scv enters with MSR[EE]=1 and is immediately considered soft-masked. + * The entry vector already sets PACAIRQSOFTMASK to IRQS_ALL_DISABLED, + * and interrupts may be masked and pending already. + * system_call_exception() will call trace_hardirqs_off() which means + * interrupts could already have been blocked before trace_hardirqs_off, + * but this is the best we can do. + */ + + /* + * Zero user registers to prevent influencing speculative execution + * state of kernel code. + */ + SANITIZE_SYSCALL_GPRS() + bl CFUNC(system_call_exception) + +.Lsyscall_vectored_\name\()_exit: + addi r4,r1,STACK_INT_FRAME_REGS + li r5,1 /* scv */ + bl CFUNC(syscall_exit_prepare) + std r1,PACA_EXIT_SAVE_R1(r13) /* save r1 for restart */ +.Lsyscall_vectored_\name\()_rst_start: + lbz r11,PACAIRQHAPPENED(r13) + andi. r11,r11,(~PACA_IRQ_HARD_DIS)@l + bne- syscall_vectored_\name\()_restart + li r11,IRQS_ENABLED + stb r11,PACAIRQSOFTMASK(r13) + li r11,0 + stb r11,PACAIRQHAPPENED(r13) # clear out possible HARD_DIS + + ld r2,_CCR(r1) + ld r4,_NIP(r1) + ld r5,_MSR(r1) + +BEGIN_FTR_SECTION + stdcx. r0,0,r1 /* to clear the reservation */ +END_FTR_SECTION_IFCLR(CPU_FTR_STCX_CHECKS_ADDRESS) + +BEGIN_FTR_SECTION + HMT_MEDIUM_LOW +END_FTR_SECTION_IFSET(CPU_FTR_HAS_PPR) + + SANITIZE_RESTORE_NVGPRS() + cmpdi r3,0 + bne .Lsyscall_vectored_\name\()_restore_regs + + /* rfscv returns with LR->NIA and CTR->MSR */ + mtlr r4 + mtctr r5 + + /* Could zero these as per ABI, but we may consider a stricter ABI + * which preserves these if libc implementations can benefit, so + * restore them for now until further measurement is done. */ + REST_GPR(0, r1) + REST_GPRS(4, 8, r1) + /* Zero volatile regs that may contain sensitive kernel data */ + ZEROIZE_GPRS(9, 12) + mtspr SPRN_XER,r0 + + /* + * We don't need to restore AMR on the way back to userspace for KUAP. + * The value of AMR only matters while we're in the kernel. + */ + mtcr r2 + REST_GPRS(2, 3, r1) + REST_GPR(13, r1) + REST_GPR(1, r1) + RFSCV_TO_USER + b . /* prevent speculative execution */ + +.Lsyscall_vectored_\name\()_restore_regs: + mtspr SPRN_SRR0,r4 + mtspr SPRN_SRR1,r5 + + ld r3,_CTR(r1) + ld r4,_LINK(r1) + ld r5,_XER(r1) + + HANDLER_RESTORE_NVGPRS() + REST_GPR(0, r1) + mtcr r2 + mtctr r3 + mtlr r4 + mtspr SPRN_XER,r5 + REST_GPRS(2, 13, r1) + REST_GPR(1, r1) + RFI_TO_USER +.Lsyscall_vectored_\name\()_rst_end: + +syscall_vectored_\name\()_restart: +_ASM_NOKPROBE_SYMBOL(syscall_vectored_\name\()_restart) + GET_PACA(r13) + ld r1,PACA_EXIT_SAVE_R1(r13) + LOAD_PACA_TOC() + ld r3,RESULT(r1) + addi r4,r1,STACK_INT_FRAME_REGS + li r11,IRQS_ALL_DISABLED + stb r11,PACAIRQSOFTMASK(r13) + bl CFUNC(syscall_exit_restart) + std r1,PACA_EXIT_SAVE_R1(r13) /* save r1 for restart */ + b .Lsyscall_vectored_\name\()_rst_start +1: + +SOFT_MASK_TABLE(.Lsyscall_vectored_\name\()_rst_start, 1b) +RESTART_TABLE(.Lsyscall_vectored_\name\()_rst_start, .Lsyscall_vectored_\name\()_rst_end, syscall_vectored_\name\()_restart) + +.endm + +system_call_vectored common 0x3000 + +/* + * We instantiate another entry copy for the SIGILL variant, with TRAP=0x7ff0 + * which is tested by system_call_exception when r0 is -1 (as set by vector + * entry code). + */ +system_call_vectored sigill 0x7ff0 + +#endif /* CONFIG_PPC_BOOK3S */ + + .balign IFETCH_ALIGN_BYTES + .globl system_call_common_real +system_call_common_real: +_ASM_NOKPROBE_SYMBOL(system_call_common_real) + ld r10,PACAKMSR(r13) /* get MSR value for kernel */ + mtmsrd r10 + + .balign IFETCH_ALIGN_BYTES + .globl system_call_common +system_call_common: +_ASM_NOKPROBE_SYMBOL(system_call_common) + mr r10,r1 + ld r1,PACAKSAVE(r13) + std r10,0(r1) + std r11,_NIP(r1) + std r12,_MSR(r1) + std r0,GPR0(r1) + std r10,GPR1(r1) + std r2,GPR2(r1) +#ifdef CONFIG_PPC_E500 +START_BTB_FLUSH_SECTION + BTB_FLUSH(r10) +END_BTB_FLUSH_SECTION +#endif + LOAD_PACA_TOC() + mfcr r12 + li r11,0 + /* Save syscall parameters in r3-r8 */ + SAVE_GPRS(3, 8, r1) + /* Zero r9-r12, this should only be required when restoring all GPRs */ + std r11,GPR9(r1) + std r11,GPR10(r1) + std r11,GPR11(r1) + std r11,GPR12(r1) + std r9,GPR13(r1) + SAVE_NVGPRS(r1) + std r11,_XER(r1) + std r11,_CTR(r1) + mflr r10 + + /* + * This clears CR0.SO (bit 28), which is the error indication on + * return from this system call. + */ + rldimi r12,r11,28,(63-28) + li r11,0xc00 + std r10,_LINK(r1) + std r11,_TRAP(r1) + std r12,_CCR(r1) + std r3,ORIG_GPR3(r1) + LOAD_REG_IMMEDIATE(r11, STACK_FRAME_REGS_MARKER) + std r11,STACK_INT_FRAME_MARKER(r1) /* "regs" marker */ + /* Calling convention has r3 = regs, r4 = orig r0 */ + addi r3,r1,STACK_INT_FRAME_REGS + mr r4,r0 + +#ifdef CONFIG_PPC_BOOK3S + li r11,1 + stb r11,PACASRR_VALID(r13) +#endif + + /* + * We always enter kernel from userspace with irq soft-mask enabled and + * nothing pending. system_call_exception() will call + * trace_hardirqs_off(). + */ + li r11,IRQS_ALL_DISABLED + stb r11,PACAIRQSOFTMASK(r13) +#ifdef CONFIG_PPC_BOOK3S + li r12,-1 /* Set MSR_EE and MSR_RI */ + mtmsrd r12,1 +#else + wrteei 1 +#endif + + /* + * Zero user registers to prevent influencing speculative execution + * state of kernel code. + */ + SANITIZE_SYSCALL_GPRS() + bl CFUNC(system_call_exception) + +.Lsyscall_exit: + addi r4,r1,STACK_INT_FRAME_REGS + li r5,0 /* !scv */ + bl CFUNC(syscall_exit_prepare) + std r1,PACA_EXIT_SAVE_R1(r13) /* save r1 for restart */ +#ifdef CONFIG_PPC_BOOK3S +.Lsyscall_rst_start: + lbz r11,PACAIRQHAPPENED(r13) + andi. r11,r11,(~PACA_IRQ_HARD_DIS)@l + bne- syscall_restart +#endif + li r11,IRQS_ENABLED + stb r11,PACAIRQSOFTMASK(r13) + li r11,0 + stb r11,PACAIRQHAPPENED(r13) # clear out possible HARD_DIS + + ld r2,_CCR(r1) + ld r6,_LINK(r1) + mtlr r6 + +#ifdef CONFIG_PPC_BOOK3S + lbz r4,PACASRR_VALID(r13) + cmpdi r4,0 + bne 1f + li r4,0 + stb r4,PACASRR_VALID(r13) +#endif + ld r4,_NIP(r1) + ld r5,_MSR(r1) + mtspr SPRN_SRR0,r4 + mtspr SPRN_SRR1,r5 +1: + DEBUG_SRR_VALID srr + +BEGIN_FTR_SECTION + stdcx. r0,0,r1 /* to clear the reservation */ +END_FTR_SECTION_IFCLR(CPU_FTR_STCX_CHECKS_ADDRESS) + + SANITIZE_RESTORE_NVGPRS() + cmpdi r3,0 + bne .Lsyscall_restore_regs + /* Zero volatile regs that may contain sensitive kernel data */ + ZEROIZE_GPR(0) + ZEROIZE_GPRS(4, 12) + mtctr r0 + mtspr SPRN_XER,r0 +.Lsyscall_restore_regs_cont: + +BEGIN_FTR_SECTION + HMT_MEDIUM_LOW +END_FTR_SECTION_IFSET(CPU_FTR_HAS_PPR) + + /* + * We don't need to restore AMR on the way back to userspace for KUAP. + * The value of AMR only matters while we're in the kernel. + */ + mtcr r2 + REST_GPRS(2, 3, r1) + REST_GPR(13, r1) + REST_GPR(1, r1) + RFI_TO_USER + b . /* prevent speculative execution */ + +.Lsyscall_restore_regs: + ld r3,_CTR(r1) + ld r4,_XER(r1) + HANDLER_RESTORE_NVGPRS() + mtctr r3 + mtspr SPRN_XER,r4 + REST_GPR(0, r1) + REST_GPRS(4, 12, r1) + b .Lsyscall_restore_regs_cont +.Lsyscall_rst_end: + +#ifdef CONFIG_PPC_BOOK3S +syscall_restart: +_ASM_NOKPROBE_SYMBOL(syscall_restart) + GET_PACA(r13) + ld r1,PACA_EXIT_SAVE_R1(r13) + LOAD_PACA_TOC() + ld r3,RESULT(r1) + addi r4,r1,STACK_INT_FRAME_REGS + li r11,IRQS_ALL_DISABLED + stb r11,PACAIRQSOFTMASK(r13) + bl CFUNC(syscall_exit_restart) + std r1,PACA_EXIT_SAVE_R1(r13) /* save r1 for restart */ + b .Lsyscall_rst_start +1: + +SOFT_MASK_TABLE(.Lsyscall_rst_start, 1b) +RESTART_TABLE(.Lsyscall_rst_start, .Lsyscall_rst_end, syscall_restart) +#endif + + /* + * If MSR EE/RI was never enabled, IRQs not reconciled, NVGPRs not + * touched, no exit work created, then this can be used. + */ + .balign IFETCH_ALIGN_BYTES + .globl fast_interrupt_return_srr +fast_interrupt_return_srr: +_ASM_NOKPROBE_SYMBOL(fast_interrupt_return_srr) + kuap_check_amr r3, r4 + ld r5,_MSR(r1) + andi. r0,r5,MSR_PR +#ifdef CONFIG_PPC_BOOK3S + beq 1f + kuap_user_restore r3, r4 + b .Lfast_user_interrupt_return_srr +1: kuap_kernel_restore r3, r4 + andi. r0,r5,MSR_RI + li r3,0 /* 0 return value, no EMULATE_STACK_STORE */ + bne+ .Lfast_kernel_interrupt_return_srr + addi r3,r1,STACK_INT_FRAME_REGS + bl CFUNC(unrecoverable_exception) + b . /* should not get here */ +#else + bne .Lfast_user_interrupt_return_srr + b .Lfast_kernel_interrupt_return_srr +#endif + +.macro interrupt_return_macro srr + .balign IFETCH_ALIGN_BYTES + .globl interrupt_return_\srr +interrupt_return_\srr\(): +_ASM_NOKPROBE_SYMBOL(interrupt_return_\srr\()) + ld r4,_MSR(r1) + andi. r0,r4,MSR_PR + beq interrupt_return_\srr\()_kernel +interrupt_return_\srr\()_user: /* make backtraces match the _kernel variant */ +_ASM_NOKPROBE_SYMBOL(interrupt_return_\srr\()_user) + addi r3,r1,STACK_INT_FRAME_REGS + bl CFUNC(interrupt_exit_user_prepare) +#ifndef CONFIG_INTERRUPT_SANITIZE_REGISTERS + cmpdi r3,0 + bne- .Lrestore_nvgprs_\srr +.Lrestore_nvgprs_\srr\()_cont: +#endif + std r1,PACA_EXIT_SAVE_R1(r13) /* save r1 for restart */ +#ifdef CONFIG_PPC_BOOK3S +.Linterrupt_return_\srr\()_user_rst_start: + lbz r11,PACAIRQHAPPENED(r13) + andi. r11,r11,(~PACA_IRQ_HARD_DIS)@l + bne- interrupt_return_\srr\()_user_restart +#endif + li r11,IRQS_ENABLED + stb r11,PACAIRQSOFTMASK(r13) + li r11,0 + stb r11,PACAIRQHAPPENED(r13) # clear out possible HARD_DIS + +.Lfast_user_interrupt_return_\srr\(): + SANITIZE_RESTORE_NVGPRS() +#ifdef CONFIG_PPC_BOOK3S + .ifc \srr,srr + lbz r4,PACASRR_VALID(r13) + .else + lbz r4,PACAHSRR_VALID(r13) + .endif + cmpdi r4,0 + li r4,0 + bne 1f +#endif + ld r11,_NIP(r1) + ld r12,_MSR(r1) + .ifc \srr,srr + mtspr SPRN_SRR0,r11 + mtspr SPRN_SRR1,r12 +1: +#ifdef CONFIG_PPC_BOOK3S + stb r4,PACASRR_VALID(r13) +#endif + .else + mtspr SPRN_HSRR0,r11 + mtspr SPRN_HSRR1,r12 +1: +#ifdef CONFIG_PPC_BOOK3S + stb r4,PACAHSRR_VALID(r13) +#endif + .endif + DEBUG_SRR_VALID \srr + +#ifdef CONFIG_PPC_IRQ_SOFT_MASK_DEBUG + lbz r4,PACAIRQSOFTMASK(r13) + tdnei r4,IRQS_ENABLED +#endif + +BEGIN_FTR_SECTION + ld r10,_PPR(r1) + mtspr SPRN_PPR,r10 +END_FTR_SECTION_IFSET(CPU_FTR_HAS_PPR) + +BEGIN_FTR_SECTION + stdcx. r0,0,r1 /* to clear the reservation */ +FTR_SECTION_ELSE + ldarx r0,0,r1 +ALT_FTR_SECTION_END_IFCLR(CPU_FTR_STCX_CHECKS_ADDRESS) + + ld r3,_CCR(r1) + ld r4,_LINK(r1) + ld r5,_CTR(r1) + ld r6,_XER(r1) + li r0,0 + + REST_GPRS(7, 13, r1) + + mtcr r3 + mtlr r4 + mtctr r5 + mtspr SPRN_XER,r6 + + REST_GPRS(2, 6, r1) + REST_GPR(0, r1) + REST_GPR(1, r1) + .ifc \srr,srr + RFI_TO_USER + .else + HRFI_TO_USER + .endif + b . /* prevent speculative execution */ +.Linterrupt_return_\srr\()_user_rst_end: + +#ifndef CONFIG_INTERRUPT_SANITIZE_REGISTERS +.Lrestore_nvgprs_\srr\(): + REST_NVGPRS(r1) + b .Lrestore_nvgprs_\srr\()_cont +#endif + +#ifdef CONFIG_PPC_BOOK3S +interrupt_return_\srr\()_user_restart: +_ASM_NOKPROBE_SYMBOL(interrupt_return_\srr\()_user_restart) + GET_PACA(r13) + ld r1,PACA_EXIT_SAVE_R1(r13) + LOAD_PACA_TOC() + addi r3,r1,STACK_INT_FRAME_REGS + li r11,IRQS_ALL_DISABLED + stb r11,PACAIRQSOFTMASK(r13) + bl CFUNC(interrupt_exit_user_restart) + std r1,PACA_EXIT_SAVE_R1(r13) /* save r1 for restart */ + b .Linterrupt_return_\srr\()_user_rst_start +1: + +SOFT_MASK_TABLE(.Linterrupt_return_\srr\()_user_rst_start, 1b) +RESTART_TABLE(.Linterrupt_return_\srr\()_user_rst_start, .Linterrupt_return_\srr\()_user_rst_end, interrupt_return_\srr\()_user_restart) +#endif + + .balign IFETCH_ALIGN_BYTES +interrupt_return_\srr\()_kernel: +_ASM_NOKPROBE_SYMBOL(interrupt_return_\srr\()_kernel) + addi r3,r1,STACK_INT_FRAME_REGS + bl CFUNC(interrupt_exit_kernel_prepare) + + std r1,PACA_EXIT_SAVE_R1(r13) /* save r1 for restart */ +.Linterrupt_return_\srr\()_kernel_rst_start: + ld r11,SOFTE(r1) + cmpwi r11,IRQS_ENABLED + stb r11,PACAIRQSOFTMASK(r13) + beq .Linterrupt_return_\srr\()_soft_enabled + + /* + * Returning to soft-disabled context. + * Check if a MUST_HARD_MASK interrupt has become pending, in which + * case we need to disable MSR[EE] in the return context. + * + * The MSR[EE] check catches among other things the short incoherency + * in hard_irq_disable() between clearing MSR[EE] and setting + * PACA_IRQ_HARD_DIS. + */ + ld r12,_MSR(r1) + andi. r10,r12,MSR_EE + beq .Lfast_kernel_interrupt_return_\srr\() // EE already disabled + lbz r11,PACAIRQHAPPENED(r13) + andi. r10,r11,PACA_IRQ_MUST_HARD_MASK + bne 1f // HARD_MASK is pending + // No HARD_MASK pending, clear possible HARD_DIS set by interrupt + andi. r11,r11,(~PACA_IRQ_HARD_DIS)@l + stb r11,PACAIRQHAPPENED(r13) + b .Lfast_kernel_interrupt_return_\srr\() + + +1: /* Must clear MSR_EE from _MSR */ +#ifdef CONFIG_PPC_BOOK3S + li r10,0 + /* Clear valid before changing _MSR */ + .ifc \srr,srr + stb r10,PACASRR_VALID(r13) + .else + stb r10,PACAHSRR_VALID(r13) + .endif +#endif + xori r12,r12,MSR_EE + std r12,_MSR(r1) + b .Lfast_kernel_interrupt_return_\srr\() + +.Linterrupt_return_\srr\()_soft_enabled: + /* + * In the soft-enabled case, need to double-check that we have no + * pending interrupts that might have come in before we reached the + * restart section of code, and restart the exit so those can be + * handled. + * + * If there are none, it is be possible that the interrupt still + * has PACA_IRQ_HARD_DIS set, which needs to be cleared for the + * interrupted context. This clear will not clobber a new pending + * interrupt coming in, because we're in the restart section, so + * such would return to the restart location. + */ +#ifdef CONFIG_PPC_BOOK3S + lbz r11,PACAIRQHAPPENED(r13) + andi. r11,r11,(~PACA_IRQ_HARD_DIS)@l + bne- interrupt_return_\srr\()_kernel_restart +#endif + li r11,0 + stb r11,PACAIRQHAPPENED(r13) // clear the possible HARD_DIS + +.Lfast_kernel_interrupt_return_\srr\(): + SANITIZE_RESTORE_NVGPRS() + cmpdi cr1,r3,0 +#ifdef CONFIG_PPC_BOOK3S + .ifc \srr,srr + lbz r4,PACASRR_VALID(r13) + .else + lbz r4,PACAHSRR_VALID(r13) + .endif + cmpdi r4,0 + li r4,0 + bne 1f +#endif + ld r11,_NIP(r1) + ld r12,_MSR(r1) + .ifc \srr,srr + mtspr SPRN_SRR0,r11 + mtspr SPRN_SRR1,r12 +1: +#ifdef CONFIG_PPC_BOOK3S + stb r4,PACASRR_VALID(r13) +#endif + .else + mtspr SPRN_HSRR0,r11 + mtspr SPRN_HSRR1,r12 +1: +#ifdef CONFIG_PPC_BOOK3S + stb r4,PACAHSRR_VALID(r13) +#endif + .endif + DEBUG_SRR_VALID \srr + +BEGIN_FTR_SECTION + stdcx. r0,0,r1 /* to clear the reservation */ +FTR_SECTION_ELSE + ldarx r0,0,r1 +ALT_FTR_SECTION_END_IFCLR(CPU_FTR_STCX_CHECKS_ADDRESS) + + ld r3,_LINK(r1) + ld r4,_CTR(r1) + ld r5,_XER(r1) + ld r6,_CCR(r1) + li r0,0 + + REST_GPRS(7, 12, r1) + + mtlr r3 + mtctr r4 + mtspr SPRN_XER,r5 + + /* + * Leaving a stale STACK_FRAME_REGS_MARKER on the stack can confuse + * the reliable stack unwinder later on. Clear it. + */ + std r0,STACK_INT_FRAME_MARKER(r1) + + REST_GPRS(2, 5, r1) + + bne- cr1,1f /* emulate stack store */ + mtcr r6 + REST_GPR(6, r1) + REST_GPR(0, r1) + REST_GPR(1, r1) + .ifc \srr,srr + RFI_TO_KERNEL + .else + HRFI_TO_KERNEL + .endif + b . /* prevent speculative execution */ + +1: /* + * Emulate stack store with update. New r1 value was already calculated + * and updated in our interrupt regs by emulate_loadstore, but we can't + * store the previous value of r1 to the stack before re-loading our + * registers from it, otherwise they could be clobbered. Use + * PACA_EXGEN as temporary storage to hold the store data, as + * interrupts are disabled here so it won't be clobbered. + */ + mtcr r6 + std r9,PACA_EXGEN+0(r13) + addi r9,r1,INT_FRAME_SIZE /* get original r1 */ + REST_GPR(6, r1) + REST_GPR(0, r1) + REST_GPR(1, r1) + std r9,0(r1) /* perform store component of stdu */ + ld r9,PACA_EXGEN+0(r13) + + .ifc \srr,srr + RFI_TO_KERNEL + .else + HRFI_TO_KERNEL + .endif + b . /* prevent speculative execution */ +.Linterrupt_return_\srr\()_kernel_rst_end: + +#ifdef CONFIG_PPC_BOOK3S +interrupt_return_\srr\()_kernel_restart: +_ASM_NOKPROBE_SYMBOL(interrupt_return_\srr\()_kernel_restart) + GET_PACA(r13) + ld r1,PACA_EXIT_SAVE_R1(r13) + LOAD_PACA_TOC() + addi r3,r1,STACK_INT_FRAME_REGS + li r11,IRQS_ALL_DISABLED + stb r11,PACAIRQSOFTMASK(r13) + bl CFUNC(interrupt_exit_kernel_restart) + std r1,PACA_EXIT_SAVE_R1(r13) /* save r1 for restart */ + b .Linterrupt_return_\srr\()_kernel_rst_start +1: + +SOFT_MASK_TABLE(.Linterrupt_return_\srr\()_kernel_rst_start, 1b) +RESTART_TABLE(.Linterrupt_return_\srr\()_kernel_rst_start, .Linterrupt_return_\srr\()_kernel_rst_end, interrupt_return_\srr\()_kernel_restart) +#endif + +.endm + +interrupt_return_macro srr +#ifdef CONFIG_PPC_BOOK3S +interrupt_return_macro hsrr + + .globl __end_soft_masked +__end_soft_masked: +DEFINE_FIXED_SYMBOL(__end_soft_masked, text) +#endif /* CONFIG_PPC_BOOK3S */ + +#ifdef CONFIG_PPC_BOOK3S +_GLOBAL(ret_from_fork_scv) + bl CFUNC(schedule_tail) + HANDLER_RESTORE_NVGPRS() + li r3,0 /* fork() return value */ + b .Lsyscall_vectored_common_exit +#endif + +_GLOBAL(ret_from_fork) + bl CFUNC(schedule_tail) + HANDLER_RESTORE_NVGPRS() + li r3,0 /* fork() return value */ + b .Lsyscall_exit + +_GLOBAL(ret_from_kernel_user_thread) + bl CFUNC(schedule_tail) + mtctr r14 + mr r3,r15 +#ifdef CONFIG_PPC64_ELF_ABI_V2 + mr r12,r14 +#endif + bctrl + li r3,0 + /* + * It does not matter whether this returns via the scv or sc path + * because it returns as execve() and therefore has no calling ABI + * (i.e., it sets registers according to the exec()ed entry point). + */ + b .Lsyscall_exit + +_GLOBAL(start_kernel_thread) + bl CFUNC(schedule_tail) + mtctr r14 + mr r3,r15 +#ifdef CONFIG_PPC64_ELF_ABI_V2 + mr r12,r14 +#endif + bctrl + /* + * This must not return. We actually want to BUG here, not WARN, + * because BUG will exit the process which is what the kernel thread + * should have done, which may give some hope of continuing. + */ +100: trap + EMIT_BUG_ENTRY 100b,__FILE__,__LINE__,0 |