diff options
Diffstat (limited to 'arch/x86/kernel')
| -rw-r--r-- | arch/x86/kernel/alternative.c | 1 | ||||
| -rw-r--r-- | arch/x86/kernel/cpu/common.c | 18 | ||||
| -rw-r--r-- | arch/x86/kernel/cpu/intel.c | 36 | ||||
| -rw-r--r-- | arch/x86/kernel/setup.c | 2 | ||||
| -rw-r--r-- | arch/x86/kernel/sys_x86_64.c | 9 | ||||
| -rw-r--r-- | arch/x86/kernel/traps.c | 74 |
6 files changed, 1 insertions, 139 deletions
diff --git a/arch/x86/kernel/alternative.c b/arch/x86/kernel/alternative.c index 34360ca301a2..15ac0d5f4b40 100644 --- a/arch/x86/kernel/alternative.c +++ b/arch/x86/kernel/alternative.c @@ -23,6 +23,7 @@ #include <asm/nmi.h> #include <asm/cacheflush.h> #include <asm/tlbflush.h> +#include <asm/insn.h> #include <asm/io.h> #include <asm/fixmap.h> diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c index 86b8241c8209..52c9bfbbdb2a 100644 --- a/arch/x86/kernel/cpu/common.c +++ b/arch/x86/kernel/cpu/common.c @@ -164,22 +164,6 @@ DEFINE_PER_CPU_PAGE_ALIGNED(struct gdt_page, gdt_page) = { .gdt = { } }; EXPORT_PER_CPU_SYMBOL_GPL(gdt_page); -static int __init x86_mpx_setup(char *s) -{ - /* require an exact match without trailing characters */ - if (strlen(s)) - return 0; - - /* do not emit a message if the feature is not present */ - if (!boot_cpu_has(X86_FEATURE_MPX)) - return 1; - - setup_clear_cpu_cap(X86_FEATURE_MPX); - pr_info("nompx: Intel Memory Protection Extensions (MPX) disabled\n"); - return 1; -} -__setup("nompx", x86_mpx_setup); - #ifdef CONFIG_X86_64 static int __init x86_nopcid_setup(char *s) { @@ -306,8 +290,6 @@ static inline void squash_the_stupid_serial_number(struct cpuinfo_x86 *c) static __init int setup_disable_smep(char *arg) { setup_clear_cpu_cap(X86_FEATURE_SMEP); - /* Check for things that depend on SMEP being enabled: */ - check_mpx_erratum(&boot_cpu_data); return 1; } __setup("nosmep", setup_disable_smep); diff --git a/arch/x86/kernel/cpu/intel.c b/arch/x86/kernel/cpu/intel.c index 57473e2c0869..be82cd5841c3 100644 --- a/arch/x86/kernel/cpu/intel.c +++ b/arch/x86/kernel/cpu/intel.c @@ -32,41 +32,6 @@ #endif /* - * Just in case our CPU detection goes bad, or you have a weird system, - * allow a way to override the automatic disabling of MPX. - */ -static int forcempx; - -static int __init forcempx_setup(char *__unused) -{ - forcempx = 1; - - return 1; -} -__setup("intel-skd-046-workaround=disable", forcempx_setup); - -void check_mpx_erratum(struct cpuinfo_x86 *c) -{ - if (forcempx) - return; - /* - * Turn off the MPX feature on CPUs where SMEP is not - * available or disabled. - * - * Works around Intel Erratum SKD046: "Branch Instructions - * May Initialize MPX Bound Registers Incorrectly". - * - * This might falsely disable MPX on systems without - * SMEP, like Atom processors without SMEP. But there - * is no such hardware known at the moment. - */ - if (cpu_has(c, X86_FEATURE_MPX) && !cpu_has(c, X86_FEATURE_SMEP)) { - setup_clear_cpu_cap(X86_FEATURE_MPX); - pr_warn("x86/mpx: Disabling MPX since SMEP not present\n"); - } -} - -/* * Processors which have self-snooping capability can handle conflicting * memory type across CPUs by snooping its own cache. However, there exists * CPU models in which having conflicting memory types still leads to @@ -330,7 +295,6 @@ static void early_init_intel(struct cpuinfo_x86 *c) c->x86_coreid_bits = get_count_order((ebx >> 16) & 0xff); } - check_mpx_erratum(c); check_memory_type_self_snoop_errata(c); /* diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c index 1e4c20a1efec..a74262c71484 100644 --- a/arch/x86/kernel/setup.c +++ b/arch/x86/kernel/setup.c @@ -893,8 +893,6 @@ void __init setup_arch(char **cmdline_p) init_mm.end_data = (unsigned long) _edata; init_mm.brk = _brk_end; - mpx_mm_init(&init_mm); - code_resource.start = __pa_symbol(_text); code_resource.end = __pa_symbol(_etext)-1; rodata_resource.start = __pa_symbol(__start_rodata); diff --git a/arch/x86/kernel/sys_x86_64.c b/arch/x86/kernel/sys_x86_64.c index f7476ce23b6e..ca3c11a17b5a 100644 --- a/arch/x86/kernel/sys_x86_64.c +++ b/arch/x86/kernel/sys_x86_64.c @@ -22,7 +22,6 @@ #include <asm/elf.h> #include <asm/ia32.h> #include <asm/syscalls.h> -#include <asm/mpx.h> /* * Align a virtual address to avoid aliasing in the I$ on AMD F15h. @@ -137,10 +136,6 @@ arch_get_unmapped_area(struct file *filp, unsigned long addr, struct vm_unmapped_area_info info; unsigned long begin, end; - addr = mpx_unmapped_area_check(addr, len, flags); - if (IS_ERR_VALUE(addr)) - return addr; - if (flags & MAP_FIXED) return addr; @@ -180,10 +175,6 @@ arch_get_unmapped_area_topdown(struct file *filp, const unsigned long addr0, unsigned long addr = addr0; struct vm_unmapped_area_info info; - addr = mpx_unmapped_area_check(addr, len, flags); - if (IS_ERR_VALUE(addr)) - return addr; - /* requested length too big for entire address space */ if (len > TASK_SIZE) return -ENOMEM; diff --git a/arch/x86/kernel/traps.c b/arch/x86/kernel/traps.c index 9e6f822922a3..6ef00eb6fbb9 100644 --- a/arch/x86/kernel/traps.c +++ b/arch/x86/kernel/traps.c @@ -52,8 +52,6 @@ #include <asm/mach_traps.h> #include <asm/alternative.h> #include <asm/fpu/xstate.h> -#include <asm/trace/mpx.h> -#include <asm/mpx.h> #include <asm/vm86.h> #include <asm/umip.h> #include <asm/insn.h> @@ -436,8 +434,6 @@ dotraplinkage void do_double_fault(struct pt_regs *regs, long error_code, unsign dotraplinkage void do_bounds(struct pt_regs *regs, long error_code) { - const struct mpx_bndcsr *bndcsr; - RCU_LOCKDEP_WARN(!rcu_is_watching(), "entry code didn't wake RCU"); if (notify_die(DIE_TRAP, "bounds", regs, error_code, X86_TRAP_BR, SIGSEGV) == NOTIFY_STOP) @@ -447,76 +443,6 @@ dotraplinkage void do_bounds(struct pt_regs *regs, long error_code) if (!user_mode(regs)) die("bounds", regs, error_code); - if (!cpu_feature_enabled(X86_FEATURE_MPX)) { - /* The exception is not from Intel MPX */ - goto exit_trap; - } - - /* - * We need to look at BNDSTATUS to resolve this exception. - * A NULL here might mean that it is in its 'init state', - * which is all zeros which indicates MPX was not - * responsible for the exception. - */ - bndcsr = get_xsave_field_ptr(XFEATURE_BNDCSR); - if (!bndcsr) - goto exit_trap; - - trace_bounds_exception_mpx(bndcsr); - /* - * The error code field of the BNDSTATUS register communicates status - * information of a bound range exception #BR or operation involving - * bound directory. - */ - switch (bndcsr->bndstatus & MPX_BNDSTA_ERROR_CODE) { - case 2: /* Bound directory has invalid entry. */ - if (mpx_handle_bd_fault()) - goto exit_trap; - break; /* Success, it was handled */ - case 1: /* Bound violation. */ - { - struct task_struct *tsk = current; - struct mpx_fault_info mpx; - - if (mpx_fault_info(&mpx, regs)) { - /* - * We failed to decode the MPX instruction. Act as if - * the exception was not caused by MPX. - */ - goto exit_trap; - } - /* - * Success, we decoded the instruction and retrieved - * an 'mpx' containing the address being accessed - * which caused the exception. This information - * allows and application to possibly handle the - * #BR exception itself. - */ - if (!do_trap_no_signal(tsk, X86_TRAP_BR, "bounds", regs, - error_code)) - break; - - show_signal(tsk, SIGSEGV, "trap ", "bounds", regs, error_code); - - force_sig_bnderr(mpx.addr, mpx.lower, mpx.upper); - break; - } - case 0: /* No exception caused by Intel MPX operations. */ - goto exit_trap; - default: - die("bounds", regs, error_code); - } - - return; - -exit_trap: - /* - * This path out is for all the cases where we could not - * handle the exception in some way (like allocating a - * table or telling userspace about it. We will also end - * up here if the kernel has MPX turned off at compile - * time.. - */ do_trap(X86_TRAP_BR, SIGSEGV, "bounds", regs, error_code, 0, NULL); } |