From e19a6ee2460bdd0d0055a6029383422773f9999a Mon Sep 17 00:00:00 2001 From: James Morse Date: Mon, 20 Jun 2016 18:28:01 +0100 Subject: arm64: kernel: Save and restore UAO and addr_limit on exception entry If we take an exception while at EL1, the exception handler inherits the original context's addr_limit and PSTATE.UAO values. To be consistent always reset addr_limit and PSTATE.UAO on (re-)entry to EL1. This prevents accidental re-use of the original context's addr_limit. Based on a similar patch for arm from Russell King. Cc: # 4.6- Acked-by: Will Deacon Reviewed-by: Mark Rutland Signed-off-by: James Morse Signed-off-by: Will Deacon --- arch/arm64/include/asm/ptrace.h | 2 ++ arch/arm64/kernel/asm-offsets.c | 1 + arch/arm64/kernel/entry.S | 19 +++++++++++++++++-- arch/arm64/mm/fault.c | 3 ++- 4 files changed, 22 insertions(+), 3 deletions(-) (limited to 'arch/arm64') diff --git a/arch/arm64/include/asm/ptrace.h b/arch/arm64/include/asm/ptrace.h index a307eb6e7fa8..7f94755089e2 100644 --- a/arch/arm64/include/asm/ptrace.h +++ b/arch/arm64/include/asm/ptrace.h @@ -117,6 +117,8 @@ struct pt_regs { }; u64 orig_x0; u64 syscallno; + u64 orig_addr_limit; + u64 unused; // maintain 16 byte alignment }; #define arch_has_single_step() (1) diff --git a/arch/arm64/kernel/asm-offsets.c b/arch/arm64/kernel/asm-offsets.c index f8e5d47f0880..2f4ba774488a 100644 --- a/arch/arm64/kernel/asm-offsets.c +++ b/arch/arm64/kernel/asm-offsets.c @@ -60,6 +60,7 @@ int main(void) DEFINE(S_PC, offsetof(struct pt_regs, pc)); DEFINE(S_ORIG_X0, offsetof(struct pt_regs, orig_x0)); DEFINE(S_SYSCALLNO, offsetof(struct pt_regs, syscallno)); + DEFINE(S_ORIG_ADDR_LIMIT, offsetof(struct pt_regs, orig_addr_limit)); DEFINE(S_FRAME_SIZE, sizeof(struct pt_regs)); BLANK(); DEFINE(MM_CONTEXT_ID, offsetof(struct mm_struct, context.id.counter)); diff --git a/arch/arm64/kernel/entry.S b/arch/arm64/kernel/entry.S index 12e8d2bcb3f9..6c3b7345a6c4 100644 --- a/arch/arm64/kernel/entry.S +++ b/arch/arm64/kernel/entry.S @@ -28,6 +28,7 @@ #include #include #include +#include #include #include @@ -97,7 +98,14 @@ mov x29, xzr // fp pointed to user-space .else add x21, sp, #S_FRAME_SIZE - .endif + get_thread_info tsk + /* Save the task's original addr_limit and set USER_DS (TASK_SIZE_64) */ + ldr x20, [tsk, #TI_ADDR_LIMIT] + str x20, [sp, #S_ORIG_ADDR_LIMIT] + mov x20, #TASK_SIZE_64 + str x20, [tsk, #TI_ADDR_LIMIT] + ALTERNATIVE(nop, SET_PSTATE_UAO(0), ARM64_HAS_UAO, CONFIG_ARM64_UAO) + .endif /* \el == 0 */ mrs x22, elr_el1 mrs x23, spsr_el1 stp lr, x21, [sp, #S_LR] @@ -128,6 +136,14 @@ .endm .macro kernel_exit, el + .if \el != 0 + /* Restore the task's original addr_limit. */ + ldr x20, [sp, #S_ORIG_ADDR_LIMIT] + str x20, [tsk, #TI_ADDR_LIMIT] + + /* No need to restore UAO, it will be restored from SPSR_EL1 */ + .endif + ldp x21, x22, [sp, #S_PC] // load ELR, SPSR .if \el == 0 ct_user_enter @@ -406,7 +422,6 @@ el1_irq: bl trace_hardirqs_off #endif - get_thread_info tsk irq_handler #ifdef CONFIG_PREEMPT diff --git a/arch/arm64/mm/fault.c b/arch/arm64/mm/fault.c index 013e2cbe7924..b1166d1e5955 100644 --- a/arch/arm64/mm/fault.c +++ b/arch/arm64/mm/fault.c @@ -280,7 +280,8 @@ static int __kprobes do_page_fault(unsigned long addr, unsigned int esr, } if (permission_fault(esr) && (addr < USER_DS)) { - if (get_fs() == KERNEL_DS) + /* regs->orig_addr_limit may be 0 if we entered from EL0 */ + if (regs->orig_addr_limit == KERNEL_DS) die("Accessing user space memory with fs=KERNEL_DS", regs, esr); if (!search_exception_tables(regs->pc)) -- cgit v1.2.3 From 47c459beabe969c6751e2ea8d1f85c5fa1652d6c Mon Sep 17 00:00:00 2001 From: Ganapatrao Kulkarni Date: Thu, 7 Jul 2016 10:18:17 +0530 Subject: arm64: Enable workaround for Cavium erratum 27456 on thunderx-81xx Cavium erratum 27456 commit 104a0c02e8b1 ("arm64: Add workaround for Cavium erratum 27456") is applicable for thunderx-81xx pass1.0 SoC as well. Adding code to enable to 81xx. Signed-off-by: Ganapatrao Kulkarni Reviewed-by: Andrew Pinski Signed-off-by: Will Deacon --- arch/arm64/include/asm/cputype.h | 2 ++ arch/arm64/kernel/cpu_errata.c | 6 ++++++ 2 files changed, 8 insertions(+) (limited to 'arch/arm64') diff --git a/arch/arm64/include/asm/cputype.h b/arch/arm64/include/asm/cputype.h index 87e1985f3be8..9d9fd4b9a72e 100644 --- a/arch/arm64/include/asm/cputype.h +++ b/arch/arm64/include/asm/cputype.h @@ -80,12 +80,14 @@ #define APM_CPU_PART_POTENZA 0x000 #define CAVIUM_CPU_PART_THUNDERX 0x0A1 +#define CAVIUM_CPU_PART_THUNDERX_81XX 0x0A2 #define BRCM_CPU_PART_VULCAN 0x516 #define MIDR_CORTEX_A53 MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_CORTEX_A53) #define MIDR_CORTEX_A57 MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_CORTEX_A57) #define MIDR_THUNDERX MIDR_CPU_MODEL(ARM_CPU_IMP_CAVIUM, CAVIUM_CPU_PART_THUNDERX) +#define MIDR_THUNDERX_81XX MIDR_CPU_MODEL(ARM_CPU_IMP_CAVIUM, CAVIUM_CPU_PART_THUNDERX_81XX) #ifndef __ASSEMBLY__ diff --git a/arch/arm64/kernel/cpu_errata.c b/arch/arm64/kernel/cpu_errata.c index d42789499f17..af716b65110d 100644 --- a/arch/arm64/kernel/cpu_errata.c +++ b/arch/arm64/kernel/cpu_errata.c @@ -98,6 +98,12 @@ const struct arm64_cpu_capabilities arm64_errata[] = { MIDR_RANGE(MIDR_THUNDERX, 0x00, (1 << MIDR_VARIANT_SHIFT) | 1), }, + { + /* Cavium ThunderX, T81 pass 1.0 */ + .desc = "Cavium erratum 27456", + .capability = ARM64_WORKAROUND_CAVIUM_27456, + MIDR_RANGE(MIDR_THUNDERX_81XX, 0x00, 0x00), + }, #endif { } -- cgit v1.2.3