diff options
Diffstat (limited to 'arch/powerpc/kernel/interrupt_64.S')
| -rw-r--r-- | arch/powerpc/kernel/interrupt_64.S | 251 |
1 files changed, 152 insertions, 99 deletions
diff --git a/arch/powerpc/kernel/interrupt_64.S b/arch/powerpc/kernel/interrupt_64.S index ce25b28cf418..1ad059a9e2fe 100644 --- a/arch/powerpc/kernel/interrupt_64.S +++ b/arch/powerpc/kernel/interrupt_64.S @@ -13,16 +13,6 @@ #include <asm/ppc_asm.h> #include <asm/ptrace.h> - .section ".toc","aw" -SYS_CALL_TABLE: - .tc sys_call_table[TC],sys_call_table - -#ifdef CONFIG_COMPAT -COMPAT_SYS_CALL_TABLE: - .tc compat_sys_call_table[TC],compat_sys_call_table -#endif - .previous - .align 7 .macro DEBUG_SRR_VALID srr @@ -62,21 +52,17 @@ _ASM_NOKPROBE_SYMBOL(system_call_vectored_\name) mr r10,r1 ld r1,PACAKSAVE(r13) std r10,0(r1) - std r11,_NIP(r1) + std r11,_LINK(r1) + std r11,_NIP(r1) /* Saved LR is also the next instruction */ std r12,_MSR(r1) std r0,GPR0(r1) std r10,GPR1(r1) std r2,GPR2(r1) - ld r2,PACATOC(r13) + LOAD_PACA_TOC() mfcr r12 li r11,0 - /* Can we avoid saving r3-r8 in common case? */ - std r3,GPR3(r1) - std r4,GPR4(r1) - std r5,GPR5(r1) - std r6,GPR6(r1) - std r7,GPR7(r1) - std r8,GPR8(r1) + /* 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) @@ -85,15 +71,17 @@ _ASM_NOKPROBE_SYMBOL(system_call_vectored_\name) 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) - addi r10,r1,STACK_FRAME_OVERHEAD - ld r11,exception_marker@toc(r2) - std r11,-16(r10) /* "regshere" marker */ + 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 @@ -108,14 +96,17 @@ END_FTR_SECTION_IFSET(CPU_FTR_HAS_PPR) * but this is the best we can do. */ - /* Calling convention has r9 = orig r0, r10 = regs */ - mr r9,r0 - bl system_call_exception + /* + * 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_FRAME_OVERHEAD + addi r4,r1,STACK_INT_FRAME_REGS li r5,1 /* scv */ - bl syscall_exit_prepare + 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) @@ -138,6 +129,7 @@ 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 @@ -148,17 +140,10 @@ END_FTR_SECTION_IFSET(CPU_FTR_HAS_PPR) /* 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. */ - ld r0,GPR0(r1) - ld r4,GPR4(r1) - ld r5,GPR5(r1) - ld r6,GPR6(r1) - ld r7,GPR7(r1) - ld r8,GPR8(r1) + REST_GPR(0, r1) + REST_GPRS(4, 8, r1) /* Zero volatile regs that may contain sensitive kernel data */ - li r9,0 - li r10,0 - li r11,0 - li r12,0 + ZEROIZE_GPRS(9, 12) mtspr SPRN_XER,r0 /* @@ -180,8 +165,8 @@ END_FTR_SECTION_IFSET(CPU_FTR_HAS_PPR) ld r4,_LINK(r1) ld r5,_XER(r1) - REST_NVGPRS(r1) - ld r0,GPR0(r1) + HANDLER_RESTORE_NVGPRS() + REST_GPR(0, r1) mtcr r2 mtctr r3 mtlr r4 @@ -195,12 +180,12 @@ syscall_vectored_\name\()_restart: _ASM_NOKPROBE_SYMBOL(syscall_vectored_\name\()_restart) GET_PACA(r13) ld r1,PACA_EXIT_SAVE_R1(r13) - ld r2,PACATOC(r13) + LOAD_PACA_TOC() ld r3,RESULT(r1) - addi r4,r1,STACK_FRAME_OVERHEAD + addi r4,r1,STACK_INT_FRAME_REGS li r11,IRQS_ALL_DISABLED stb r11,PACAIRQSOFTMASK(r13) - bl syscall_exit_restart + bl CFUNC(syscall_exit_restart) std r1,PACA_EXIT_SAVE_R1(r13) /* save r1 for restart */ b .Lsyscall_vectored_\name\()_rst_start 1: @@ -240,21 +225,16 @@ _ASM_NOKPROBE_SYMBOL(system_call_common) std r0,GPR0(r1) std r10,GPR1(r1) std r2,GPR2(r1) -#ifdef CONFIG_PPC_FSL_BOOK3E +#ifdef CONFIG_PPC_E500 START_BTB_FLUSH_SECTION BTB_FLUSH(r10) END_BTB_FLUSH_SECTION #endif - ld r2,PACATOC(r13) + LOAD_PACA_TOC() mfcr r12 li r11,0 - /* Can we avoid saving r3-r8 in common case? */ - std r3,GPR3(r1) - std r4,GPR4(r1) - std r5,GPR5(r1) - std r6,GPR6(r1) - std r7,GPR7(r1) - std r8,GPR8(r1) + /* 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) @@ -275,9 +255,12 @@ END_BTB_FLUSH_SECTION std r10,_LINK(r1) std r11,_TRAP(r1) std r12,_CCR(r1) - addi r10,r1,STACK_FRAME_OVERHEAD - ld r11,exception_marker@toc(r2) - std r11,-16(r10) /* "regshere" marker */ + 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 @@ -298,14 +281,17 @@ END_BTB_FLUSH_SECTION wrteei 1 #endif - /* Calling convention has r9 = orig r0, r10 = regs */ - mr r9,r0 - bl system_call_exception + /* + * 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_FRAME_OVERHEAD + addi r4,r1,STACK_INT_FRAME_REGS li r5,0 /* !scv */ - bl syscall_exit_prepare + bl CFUNC(syscall_exit_prepare) std r1,PACA_EXIT_SAVE_R1(r13) /* save r1 for restart */ #ifdef CONFIG_PPC_BOOK3S .Lsyscall_rst_start: @@ -340,19 +326,12 @@ 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 */ - li r0,0 - li r4,0 - li r5,0 - li r6,0 - li r7,0 - li r8,0 - li r9,0 - li r10,0 - li r11,0 - li r12,0 + ZEROIZE_GPR(0) + ZEROIZE_GPRS(4, 12) mtctr r0 mtspr SPRN_XER,r0 .Lsyscall_restore_regs_cont: @@ -375,10 +354,10 @@ END_FTR_SECTION_IFSET(CPU_FTR_HAS_PPR) .Lsyscall_restore_regs: ld r3,_CTR(r1) ld r4,_XER(r1) - REST_NVGPRS(r1) + HANDLER_RESTORE_NVGPRS() mtctr r3 mtspr SPRN_XER,r4 - ld r0,GPR0(r1) + REST_GPR(0, r1) REST_GPRS(4, 12, r1) b .Lsyscall_restore_regs_cont .Lsyscall_rst_end: @@ -388,12 +367,12 @@ syscall_restart: _ASM_NOKPROBE_SYMBOL(syscall_restart) GET_PACA(r13) ld r1,PACA_EXIT_SAVE_R1(r13) - ld r2,PACATOC(r13) + LOAD_PACA_TOC() ld r3,RESULT(r1) - addi r4,r1,STACK_FRAME_OVERHEAD + addi r4,r1,STACK_INT_FRAME_REGS li r11,IRQS_ALL_DISABLED stb r11,PACAIRQSOFTMASK(r13) - bl syscall_exit_restart + bl CFUNC(syscall_exit_restart) std r1,PACA_EXIT_SAVE_R1(r13) /* save r1 for restart */ b .Lsyscall_rst_start 1: @@ -421,8 +400,8 @@ _ASM_NOKPROBE_SYMBOL(fast_interrupt_return_srr) 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_FRAME_OVERHEAD - bl unrecoverable_exception + addi r3,r1,STACK_INT_FRAME_REGS + bl CFUNC(unrecoverable_exception) b . /* should not get here */ #else bne .Lfast_user_interrupt_return_srr @@ -439,11 +418,13 @@ _ASM_NOKPROBE_SYMBOL(interrupt_return_\srr\()) 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_FRAME_OVERHEAD - bl interrupt_exit_user_prepare + 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: @@ -457,6 +438,7 @@ _ASM_NOKPROBE_SYMBOL(interrupt_return_\srr\()_user) 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) @@ -526,20 +508,22 @@ ALT_FTR_SECTION_END_IFCLR(CPU_FTR_STCX_CHECKS_ADDRESS) 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) - ld r2,PACATOC(r13) - addi r3,r1,STACK_FRAME_OVERHEAD + LOAD_PACA_TOC() + addi r3,r1,STACK_INT_FRAME_REGS li r11,IRQS_ALL_DISABLED stb r11,PACAIRQSOFTMASK(r13) - bl interrupt_exit_user_restart + 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: @@ -551,25 +535,74 @@ RESTART_TABLE(.Linterrupt_return_\srr\()_user_rst_start, .Linterrupt_return_\srr .balign IFETCH_ALIGN_BYTES interrupt_return_\srr\()_kernel: _ASM_NOKPROBE_SYMBOL(interrupt_return_\srr\()_kernel) - addi r3,r1,STACK_FRAME_OVERHEAD - bl interrupt_exit_kernel_prepare + 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) - bne 1f + 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 out possible HARD_DIS -1: + 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 @@ -619,10 +652,10 @@ ALT_FTR_SECTION_END_IFCLR(CPU_FTR_STCX_CHECKS_ADDRESS) mtspr SPRN_XER,r5 /* - * Leaving a stale exception_marker on the stack can confuse + * Leaving a stale STACK_FRAME_REGS_MARKER on the stack can confuse * the reliable stack unwinder later on. Clear it. */ - std r0,STACK_FRAME_OVERHEAD-16(r1) + std r0,STACK_INT_FRAME_MARKER(r1) REST_GPRS(2, 5, r1) @@ -668,11 +701,11 @@ interrupt_return_\srr\()_kernel_restart: _ASM_NOKPROBE_SYMBOL(interrupt_return_\srr\()_kernel_restart) GET_PACA(r13) ld r1,PACA_EXIT_SAVE_R1(r13) - ld r2,PACATOC(r13) - addi r3,r1,STACK_FRAME_OVERHEAD + LOAD_PACA_TOC() + addi r3,r1,STACK_INT_FRAME_REGS li r11,IRQS_ALL_DISABLED stb r11,PACAIRQSOFTMASK(r13) - bl interrupt_exit_kernel_restart + 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: @@ -694,21 +727,20 @@ DEFINE_FIXED_SYMBOL(__end_soft_masked, text) #ifdef CONFIG_PPC_BOOK3S _GLOBAL(ret_from_fork_scv) - bl schedule_tail - REST_NVGPRS(r1) + bl CFUNC(schedule_tail) + HANDLER_RESTORE_NVGPRS() li r3,0 /* fork() return value */ b .Lsyscall_vectored_common_exit #endif _GLOBAL(ret_from_fork) - bl schedule_tail - REST_NVGPRS(r1) + bl CFUNC(schedule_tail) + HANDLER_RESTORE_NVGPRS() li r3,0 /* fork() return value */ b .Lsyscall_exit -_GLOBAL(ret_from_kernel_thread) - bl schedule_tail - REST_NVGPRS(r1) +_GLOBAL(ret_from_kernel_user_thread) + bl CFUNC(schedule_tail) mtctr r14 mr r3,r15 #ifdef CONFIG_PPC64_ELF_ABI_V2 @@ -716,4 +748,25 @@ _GLOBAL(ret_from_kernel_thread) #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 |