diff options
Diffstat (limited to 'arch/powerpc/kernel/entry_64.S')
-rw-r--r-- | arch/powerpc/kernel/entry_64.S | 41 |
1 files changed, 27 insertions, 14 deletions
diff --git a/arch/powerpc/kernel/entry_64.S b/arch/powerpc/kernel/entry_64.S index 15c67d2c0534..d9105fcf4021 100644 --- a/arch/powerpc/kernel/entry_64.S +++ b/arch/powerpc/kernel/entry_64.S @@ -1,3 +1,4 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ /* * PowerPC version * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org) @@ -11,11 +12,6 @@ * * This file contains the system call entry code, context switch * code, and exception/interrupt return code for PowerPC. - * - * This program is free software; you can redistribute it and/or - * modify it under the terms of the GNU General Public License - * as published by the Free Software Foundation; either version - * 2 of the License, or (at your option) any later version. */ #include <linux/errno.h> @@ -46,6 +42,7 @@ #include <asm/exception-64e.h> #endif #include <asm/feature-fixups.h> +#include <asm/kup.h> /* * System calls. @@ -120,6 +117,9 @@ END_BTB_FLUSH_SECTION addi r9,r1,STACK_FRAME_OVERHEAD ld r11,exception_marker@toc(r2) std r11,-16(r9) /* "regshere" marker */ + + kuap_check_amr r10, r11 + #if defined(CONFIG_VIRT_CPU_ACCOUNTING_NATIVE) && defined(CONFIG_PPC_SPLPAR) BEGIN_FW_FTR_SECTION beq 33f @@ -275,6 +275,8 @@ END_FTR_SECTION_IFCLR(CPU_FTR_STCX_CHECKS_ADDRESS) andi. r6,r8,MSR_PR ld r4,_LINK(r1) + kuap_check_amr r10, r11 + #ifdef CONFIG_PPC_BOOK3S /* * Clear MSR_RI, MSR_EE is already and remains disabled. We could do @@ -296,6 +298,10 @@ END_FTR_SECTION_IFSET(CPU_FTR_HAS_PPR) std r8, PACATMSCRATCH(r13) #endif + /* + * 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. + */ ld r13,GPR13(r1) /* only restore r13 if returning to usermode */ ld r2,GPR2(r1) ld r1,GPR1(r1) @@ -306,8 +312,10 @@ END_FTR_SECTION_IFSET(CPU_FTR_HAS_PPR) RFI_TO_USER b . /* prevent speculative execution */ - /* exit to kernel */ -1: ld r2,GPR2(r1) +1: /* exit to kernel */ + kuap_restore_amr r2 + + ld r2,GPR2(r1) ld r1,GPR1(r1) mtlr r4 mtcr r5 @@ -594,6 +602,8 @@ _GLOBAL(_switch) std r23,_CCR(r1) std r1,KSP(r3) /* Set old stack pointer */ + kuap_check_amr r9, r10 + FLUSH_COUNT_CACHE /* @@ -851,13 +861,7 @@ resume_kernel: * sure we are soft-disabled first and reconcile irq state. */ RECONCILE_IRQ_STATE(r3,r4) -1: bl preempt_schedule_irq - - /* Re-test flags and eventually loop */ - ld r9, PACA_THREAD_INFO(r13) - ld r4,TI_FLAGS(r9) - andi. r0,r4,_TIF_NEED_RESCHED - bne 1b + bl preempt_schedule_irq /* * arch_local_irq_restore() from preempt_schedule_irq above may @@ -942,6 +946,8 @@ fast_exception_return: ld r4,_XER(r1) mtspr SPRN_XER,r4 + kuap_check_amr r5, r6 + REST_8GPRS(5, r1) andi. r0,r3,MSR_RI @@ -974,6 +980,10 @@ END_FTR_SECTION_IFSET(CPU_FTR_HAS_PPR) ACCOUNT_CPU_USER_EXIT(r13, r2, r4) REST_GPR(13, r1) + /* + * 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. + */ mtspr SPRN_SRR1,r3 ld r2,_CCR(r1) @@ -1006,6 +1016,9 @@ END_FTR_SECTION_IFSET(CPU_FTR_HAS_PPR) ld r0,GPR0(r1) ld r2,GPR2(r1) ld r3,GPR3(r1) + + kuap_restore_amr r4 + ld r4,GPR4(r1) ld r1,GPR1(r1) RFI_TO_KERNEL |