diff options
Diffstat (limited to 'arch/powerpc/kernel/interrupt_64.S')
| -rw-r--r-- | arch/powerpc/kernel/interrupt_64.S | 67 |
1 files changed, 47 insertions, 20 deletions
diff --git a/arch/powerpc/kernel/interrupt_64.S b/arch/powerpc/kernel/interrupt_64.S index 978a173eb339..fccc34489add 100644 --- a/arch/powerpc/kernel/interrupt_64.S +++ b/arch/powerpc/kernel/interrupt_64.S @@ -77,11 +77,11 @@ _ASM_NOKPROBE_SYMBOL(system_call_vectored_\name) 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_FRAME_OVERHEAD + addi r3,r1,STACK_INT_FRAME_REGS mr r4,r0 - LOAD_REG_IMMEDIATE(r11, STACK_FRAME_REGS_MARKER) - std r11,-16(r3) /* "regshere" marker */ BEGIN_FTR_SECTION HMT_MEDIUM @@ -96,10 +96,15 @@ END_FTR_SECTION_IFSET(CPU_FTR_HAS_PPR) * but this is the best we can do. */ + /* + * Zero user registers to prevent influencing speculative execution + * state of kernel code. + */ + SANITIZE_SYSCALL_GPRS() bl 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 std r1,PACA_EXIT_SAVE_R1(r13) /* save r1 for restart */ @@ -124,6 +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 @@ -159,7 +165,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_HAS_PPR) ld r4,_LINK(r1) ld r5,_XER(r1) - REST_NVGPRS(r1) + HANDLER_RESTORE_NVGPRS() REST_GPR(0, r1) mtcr r2 mtctr r3 @@ -176,7 +182,7 @@ _ASM_NOKPROBE_SYMBOL(syscall_vectored_\name\()_restart) ld r1,PACA_EXIT_SAVE_R1(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 @@ -250,11 +256,11 @@ END_BTB_FLUSH_SECTION 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_FRAME_OVERHEAD + addi r3,r1,STACK_INT_FRAME_REGS mr r4,r0 - LOAD_REG_IMMEDIATE(r11, STACK_FRAME_REGS_MARKER) - std r11,-16(r3) /* "regshere" marker */ #ifdef CONFIG_PPC_BOOK3S li r11,1 @@ -275,10 +281,15 @@ END_BTB_FLUSH_SECTION wrteei 1 #endif + /* + * Zero user registers to prevent influencing speculative execution + * state of kernel code. + */ + SANITIZE_SYSCALL_GPRS() bl 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 std r1,PACA_EXIT_SAVE_R1(r13) /* save r1 for restart */ @@ -315,6 +326,7 @@ 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 */ @@ -342,7 +354,7 @@ 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 REST_GPR(0, r1) @@ -357,7 +369,7 @@ _ASM_NOKPROBE_SYMBOL(syscall_restart) ld r1,PACA_EXIT_SAVE_R1(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 @@ -388,7 +400,7 @@ _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 + addi r3,r1,STACK_INT_FRAME_REGS bl unrecoverable_exception b . /* should not get here */ #else @@ -406,11 +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 + addi r3,r1,STACK_INT_FRAME_REGS bl 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: @@ -424,6 +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) @@ -493,9 +508,11 @@ 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: @@ -503,7 +520,7 @@ _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_FRAME_OVERHEAD + addi r3,r1,STACK_INT_FRAME_REGS li r11,IRQS_ALL_DISABLED stb r11,PACAIRQSOFTMASK(r13) bl interrupt_exit_user_restart @@ -518,7 +535,7 @@ 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 + addi r3,r1,STACK_INT_FRAME_REGS bl interrupt_exit_kernel_prepare std r1,PACA_EXIT_SAVE_R1(r13) /* save r1 for restart */ @@ -532,15 +549,24 @@ _ASM_NOKPROBE_SYMBOL(interrupt_return_\srr\()_kernel) * 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 - beq .Lfast_kernel_interrupt_return_\srr\() // No HARD_MASK pending + 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\() + - /* Must clear MSR_EE from _MSR */ +1: /* Must clear MSR_EE from _MSR */ #ifdef CONFIG_PPC_BOOK3S li r10,0 /* Clear valid before changing _MSR */ @@ -576,6 +602,7 @@ _ASM_NOKPROBE_SYMBOL(interrupt_return_\srr\()_kernel) 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 @@ -628,7 +655,7 @@ ALT_FTR_SECTION_END_IFCLR(CPU_FTR_STCX_CHECKS_ADDRESS) * 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) @@ -675,7 +702,7 @@ _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_FRAME_OVERHEAD + addi r3,r1,STACK_INT_FRAME_REGS li r11,IRQS_ALL_DISABLED stb r11,PACAIRQSOFTMASK(r13) bl interrupt_exit_kernel_restart |