diff options
Diffstat (limited to 'arch/x86/kernel')
29 files changed, 286 insertions, 127 deletions
diff --git a/arch/x86/kernel/apic/apic_numachip.c b/arch/x86/kernel/apic/apic_numachip.c index c80c02c6ec49..ab5c2c685a3c 100644 --- a/arch/x86/kernel/apic/apic_numachip.c +++ b/arch/x86/kernel/apic/apic_numachip.c @@ -30,7 +30,7 @@ static unsigned int numachip1_get_apic_id(unsigned long x) unsigned long value; unsigned int id = (x >> 24) & 0xff; - if (static_cpu_has_safe(X86_FEATURE_NODEID_MSR)) { + if (static_cpu_has(X86_FEATURE_NODEID_MSR)) { rdmsrl(MSR_FAM10H_NODE_ID, value); id |= (value << 2) & 0xff00; } @@ -178,7 +178,7 @@ static void fixup_cpu_id(struct cpuinfo_x86 *c, int node) this_cpu_write(cpu_llc_id, node); /* Account for nodes per socket in multi-core-module processors */ - if (static_cpu_has_safe(X86_FEATURE_NODEID_MSR)) { + if (static_cpu_has(X86_FEATURE_NODEID_MSR)) { rdmsrl(MSR_FAM10H_NODE_ID, val); nodes = ((val >> 3) & 7) + 1; } diff --git a/arch/x86/kernel/asm-offsets.c b/arch/x86/kernel/asm-offsets.c index 84a7524b202c..5c042466f274 100644 --- a/arch/x86/kernel/asm-offsets.c +++ b/arch/x86/kernel/asm-offsets.c @@ -59,7 +59,6 @@ void common(void) { #ifdef CONFIG_PARAVIRT BLANK(); - OFFSET(PARAVIRT_enabled, pv_info, paravirt_enabled); OFFSET(PARAVIRT_PATCH_pv_cpu_ops, paravirt_patch_template, pv_cpu_ops); OFFSET(PARAVIRT_PATCH_pv_irq_ops, paravirt_patch_template, pv_irq_ops); OFFSET(PV_IRQ_irq_disable, pv_irq_ops, irq_disable); diff --git a/arch/x86/kernel/asm-offsets_32.c b/arch/x86/kernel/asm-offsets_32.c index 6ce39025f467..ecdc1d217dc0 100644 --- a/arch/x86/kernel/asm-offsets_32.c +++ b/arch/x86/kernel/asm-offsets_32.c @@ -7,7 +7,7 @@ #include <linux/lguest.h> #include "../../../drivers/lguest/lg.h" -#define __SYSCALL_I386(nr, sym, compat) [nr] = 1, +#define __SYSCALL_I386(nr, sym, qual) [nr] = 1, static char syscalls[] = { #include <asm/syscalls_32.h> }; @@ -52,6 +52,11 @@ void foo(void) DEFINE(TSS_sysenter_sp0, offsetof(struct tss_struct, x86_tss.sp0) - offsetofend(struct tss_struct, SYSENTER_stack)); + /* Offset from cpu_tss to SYSENTER_stack */ + OFFSET(CPU_TSS_SYSENTER_stack, tss_struct, SYSENTER_stack); + /* Size of SYSENTER_stack */ + DEFINE(SIZEOF_SYSENTER_stack, sizeof(((struct tss_struct *)0)->SYSENTER_stack)); + #if defined(CONFIG_LGUEST) || defined(CONFIG_LGUEST_GUEST) || defined(CONFIG_LGUEST_MODULE) BLANK(); OFFSET(LGUEST_DATA_irq_enabled, lguest_data, irq_enabled); diff --git a/arch/x86/kernel/asm-offsets_64.c b/arch/x86/kernel/asm-offsets_64.c index f2edafb5f24e..d875f97d4e0b 100644 --- a/arch/x86/kernel/asm-offsets_64.c +++ b/arch/x86/kernel/asm-offsets_64.c @@ -4,17 +4,11 @@ #include <asm/ia32.h> -#define __SYSCALL_64(nr, sym, compat) [nr] = 1, -#define __SYSCALL_COMMON(nr, sym, compat) [nr] = 1, -#ifdef CONFIG_X86_X32_ABI -# define __SYSCALL_X32(nr, sym, compat) [nr] = 1, -#else -# define __SYSCALL_X32(nr, sym, compat) /* nothing */ -#endif +#define __SYSCALL_64(nr, sym, qual) [nr] = 1, static char syscalls_64[] = { #include <asm/syscalls_64.h> }; -#define __SYSCALL_I386(nr, sym, compat) [nr] = 1, +#define __SYSCALL_I386(nr, sym, qual) [nr] = 1, static char syscalls_ia32[] = { #include <asm/syscalls_32.h> }; diff --git a/arch/x86/kernel/cpu/Makefile b/arch/x86/kernel/cpu/Makefile index 7a60424d63fa..0d373d7affc8 100644 --- a/arch/x86/kernel/cpu/Makefile +++ b/arch/x86/kernel/cpu/Makefile @@ -42,7 +42,7 @@ ifdef CONFIG_X86_FEATURE_NAMES quiet_cmd_mkcapflags = MKCAP $@ cmd_mkcapflags = $(CONFIG_SHELL) $(srctree)/$(src)/mkcapflags.sh $< $@ -cpufeature = $(src)/../../include/asm/cpufeature.h +cpufeature = $(src)/../../include/asm/cpufeatures.h targets += capflags.c $(obj)/capflags.c: $(cpufeature) $(src)/mkcapflags.sh FORCE diff --git a/arch/x86/kernel/cpu/centaur.c b/arch/x86/kernel/cpu/centaur.c index ce197bb7c129..1661d8ec9280 100644 --- a/arch/x86/kernel/cpu/centaur.c +++ b/arch/x86/kernel/cpu/centaur.c @@ -1,7 +1,7 @@ #include <linux/bitops.h> #include <linux/kernel.h> -#include <asm/processor.h> +#include <asm/cpufeature.h> #include <asm/e820.h> #include <asm/mtrr.h> #include <asm/msr.h> diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c index 81cf716f6f97..4e8d25d395ee 100644 --- a/arch/x86/kernel/cpu/common.c +++ b/arch/x86/kernel/cpu/common.c @@ -801,6 +801,31 @@ static void detect_nopl(struct cpuinfo_x86 *c) #else set_cpu_cap(c, X86_FEATURE_NOPL); #endif + + /* + * ESPFIX is a strange bug. All real CPUs have it. Paravirt + * systems that run Linux at CPL > 0 may or may not have the + * issue, but, even if they have the issue, there's absolutely + * nothing we can do about it because we can't use the real IRET + * instruction. + * + * NB: For the time being, only 32-bit kernels support + * X86_BUG_ESPFIX as such. 64-bit kernels directly choose + * whether to apply espfix using paravirt hooks. If any + * non-paravirt system ever shows up that does *not* have the + * ESPFIX issue, we can change this. + */ +#ifdef CONFIG_X86_32 +#ifdef CONFIG_PARAVIRT + do { + extern void native_iret(void); + if (pv_cpu_ops.iret == native_iret) + set_cpu_bug(c, X86_BUG_ESPFIX); + } while (0); +#else + set_cpu_bug(c, X86_BUG_ESPFIX); +#endif +#endif } static void generic_identify(struct cpuinfo_x86 *c) @@ -1475,20 +1500,6 @@ void cpu_init(void) } #endif -#ifdef CONFIG_X86_DEBUG_STATIC_CPU_HAS -void warn_pre_alternatives(void) -{ - WARN(1, "You're using static_cpu_has before alternatives have run!\n"); -} -EXPORT_SYMBOL_GPL(warn_pre_alternatives); -#endif - -inline bool __static_cpu_has_safe(u16 bit) -{ - return boot_cpu_has(bit); -} -EXPORT_SYMBOL_GPL(__static_cpu_has_safe); - static void bsp_resume(void) { if (this_cpu->c_bsp_resume) diff --git a/arch/x86/kernel/cpu/cyrix.c b/arch/x86/kernel/cpu/cyrix.c index 187bb583d0df..6adef9cac23e 100644 --- a/arch/x86/kernel/cpu/cyrix.c +++ b/arch/x86/kernel/cpu/cyrix.c @@ -8,6 +8,7 @@ #include <linux/timer.h> #include <asm/pci-direct.h> #include <asm/tsc.h> +#include <asm/cpufeature.h> #include "cpu.h" diff --git a/arch/x86/kernel/cpu/intel.c b/arch/x86/kernel/cpu/intel.c index 38766c2b5b00..1f7fdb91a818 100644 --- a/arch/x86/kernel/cpu/intel.c +++ b/arch/x86/kernel/cpu/intel.c @@ -8,7 +8,7 @@ #include <linux/module.h> #include <linux/uaccess.h> -#include <asm/processor.h> +#include <asm/cpufeature.h> #include <asm/pgtable.h> #include <asm/msr.h> #include <asm/bugs.h> diff --git a/arch/x86/kernel/cpu/intel_cacheinfo.c b/arch/x86/kernel/cpu/intel_cacheinfo.c index 6ed779efff26..de6626c18e42 100644 --- a/arch/x86/kernel/cpu/intel_cacheinfo.c +++ b/arch/x86/kernel/cpu/intel_cacheinfo.c @@ -14,7 +14,7 @@ #include <linux/sysfs.h> #include <linux/pci.h> -#include <asm/processor.h> +#include <asm/cpufeature.h> #include <asm/amd_nb.h> #include <asm/smp.h> diff --git a/arch/x86/kernel/cpu/match.c b/arch/x86/kernel/cpu/match.c index afa9f0d487ea..fbb5e90557a5 100644 --- a/arch/x86/kernel/cpu/match.c +++ b/arch/x86/kernel/cpu/match.c @@ -1,5 +1,5 @@ #include <asm/cpu_device_id.h> -#include <asm/processor.h> +#include <asm/cpufeature.h> #include <linux/cpu.h> #include <linux/module.h> #include <linux/slab.h> diff --git a/arch/x86/kernel/cpu/mcheck/mce.c b/arch/x86/kernel/cpu/mcheck/mce.c index 524f2a8492d7..f0c921b03e42 100644 --- a/arch/x86/kernel/cpu/mcheck/mce.c +++ b/arch/x86/kernel/cpu/mcheck/mce.c @@ -1578,6 +1578,17 @@ static int __mcheck_cpu_apply_quirks(struct cpuinfo_x86 *c) if (c->x86 == 6 && c->x86_model == 45) quirk_no_way_out = quirk_sandybridge_ifu; + /* + * MCG_CAP.MCG_SER_P is necessary but not sufficient to know + * whether this processor will actually generate recoverable + * machine checks. Check to see if this is an E7 model Xeon. + * We can't do a model number check because E5 and E7 use the + * same model number. E5 doesn't support recovery, E7 does. + */ + if (mca_cfg.recovery || (mca_cfg.ser && + !strncmp(c->x86_model_id, + "Intel(R) Xeon(R) CPU E7-", 24))) + set_cpu_cap(c, X86_FEATURE_MCE_RECOVERY); } if (cfg->monarch_timeout < 0) cfg->monarch_timeout = 0; @@ -2030,6 +2041,8 @@ static int __init mcheck_enable(char *str) cfg->bootlog = (str[0] == 'b'); else if (!strcmp(str, "bios_cmci_threshold")) cfg->bios_cmci_threshold = true; + else if (!strcmp(str, "recovery")) + cfg->recovery = true; else if (isdigit(str[0])) { if (get_option(&str, &cfg->tolerant) == 2) get_option(&str, &(cfg->monarch_timeout)); diff --git a/arch/x86/kernel/cpu/mkcapflags.sh b/arch/x86/kernel/cpu/mkcapflags.sh index 3f20710a5b23..6988c74409a8 100644 --- a/arch/x86/kernel/cpu/mkcapflags.sh +++ b/arch/x86/kernel/cpu/mkcapflags.sh @@ -1,6 +1,6 @@ #!/bin/sh # -# Generate the x86_cap/bug_flags[] arrays from include/asm/cpufeature.h +# Generate the x86_cap/bug_flags[] arrays from include/asm/cpufeatures.h # IN=$1 @@ -49,8 +49,8 @@ dump_array() trap 'rm "$OUT"' EXIT ( - echo "#ifndef _ASM_X86_CPUFEATURE_H" - echo "#include <asm/cpufeature.h>" + echo "#ifndef _ASM_X86_CPUFEATURES_H" + echo "#include <asm/cpufeatures.h>" echo "#endif" echo "" diff --git a/arch/x86/kernel/cpu/mtrr/main.c b/arch/x86/kernel/cpu/mtrr/main.c index ba80d68f683e..10f8d4796240 100644 --- a/arch/x86/kernel/cpu/mtrr/main.c +++ b/arch/x86/kernel/cpu/mtrr/main.c @@ -47,7 +47,7 @@ #include <linux/smp.h> #include <linux/syscore_ops.h> -#include <asm/processor.h> +#include <asm/cpufeature.h> #include <asm/e820.h> #include <asm/mtrr.h> #include <asm/msr.h> diff --git a/arch/x86/kernel/cpu/transmeta.c b/arch/x86/kernel/cpu/transmeta.c index e3b4d1841175..34178564be2a 100644 --- a/arch/x86/kernel/cpu/transmeta.c +++ b/arch/x86/kernel/cpu/transmeta.c @@ -1,6 +1,6 @@ #include <linux/kernel.h> #include <linux/mm.h> -#include <asm/processor.h> +#include <asm/cpufeature.h> #include <asm/msr.h> #include "cpu.h" diff --git a/arch/x86/kernel/e820.c b/arch/x86/kernel/e820.c index 837365f10912..621b501f8935 100644 --- a/arch/x86/kernel/e820.c +++ b/arch/x86/kernel/e820.c @@ -24,6 +24,7 @@ #include <asm/e820.h> #include <asm/proto.h> #include <asm/setup.h> +#include <asm/cpufeature.h> /* * The e820 map is the map that gets modified e.g. with command line parameters diff --git a/arch/x86/kernel/fpu/xstate.c b/arch/x86/kernel/fpu/xstate.c index d425cda5ae6d..6e8354f5a593 100644 --- a/arch/x86/kernel/fpu/xstate.c +++ b/arch/x86/kernel/fpu/xstate.c @@ -51,6 +51,9 @@ void fpu__xstate_clear_all_cpu_caps(void) setup_clear_cpu_cap(X86_FEATURE_AVX512PF); setup_clear_cpu_cap(X86_FEATURE_AVX512ER); setup_clear_cpu_cap(X86_FEATURE_AVX512CD); + setup_clear_cpu_cap(X86_FEATURE_AVX512DQ); + setup_clear_cpu_cap(X86_FEATURE_AVX512BW); + setup_clear_cpu_cap(X86_FEATURE_AVX512VL); setup_clear_cpu_cap(X86_FEATURE_MPX); setup_clear_cpu_cap(X86_FEATURE_XGETBV1); } diff --git a/arch/x86/kernel/ftrace.c b/arch/x86/kernel/ftrace.c index 05c9e3f5b6d7..702547ce33c9 100644 --- a/arch/x86/kernel/ftrace.c +++ b/arch/x86/kernel/ftrace.c @@ -697,9 +697,8 @@ static inline void tramp_free(void *tramp) { } #endif /* Defined as markers to the end of the ftrace default trampolines */ -extern void ftrace_caller_end(void); extern void ftrace_regs_caller_end(void); -extern void ftrace_return(void); +extern void ftrace_epilogue(void); extern void ftrace_caller_op_ptr(void); extern void ftrace_regs_caller_op_ptr(void); @@ -746,7 +745,7 @@ create_trampoline(struct ftrace_ops *ops, unsigned int *tramp_size) op_offset = (unsigned long)ftrace_regs_caller_op_ptr; } else { start_offset = (unsigned long)ftrace_caller; - end_offset = (unsigned long)ftrace_caller_end; + end_offset = (unsigned long)ftrace_epilogue; op_offset = (unsigned long)ftrace_caller_op_ptr; } @@ -754,7 +753,7 @@ create_trampoline(struct ftrace_ops *ops, unsigned int *tramp_size) /* * Allocate enough size to store the ftrace_caller code, - * the jmp to ftrace_return, as well as the address of + * the jmp to ftrace_epilogue, as well as the address of * the ftrace_ops this trampoline is used for. */ trampoline = alloc_tramp(size + MCOUNT_INSN_SIZE + sizeof(void *)); @@ -772,8 +771,8 @@ create_trampoline(struct ftrace_ops *ops, unsigned int *tramp_size) ip = (unsigned long)trampoline + size; - /* The trampoline ends with a jmp to ftrace_return */ - jmp = ftrace_jmp_replace(ip, (unsigned long)ftrace_return); + /* The trampoline ends with a jmp to ftrace_epilogue */ + jmp = ftrace_jmp_replace(ip, (unsigned long)ftrace_epilogue); memcpy(trampoline + size, jmp, MCOUNT_INSN_SIZE); /* diff --git a/arch/x86/kernel/head_32.S b/arch/x86/kernel/head_32.S index 6bc9ae24b6d2..af1112980dd4 100644 --- a/arch/x86/kernel/head_32.S +++ b/arch/x86/kernel/head_32.S @@ -19,7 +19,7 @@ #include <asm/setup.h> #include <asm/processor-flags.h> #include <asm/msr-index.h> -#include <asm/cpufeature.h> +#include <asm/cpufeatures.h> #include <asm/percpu.h> #include <asm/nops.h> #include <asm/bootparam.h> diff --git a/arch/x86/kernel/head_64.S b/arch/x86/kernel/head_64.S index ffdc0e860390..2e974680f5ad 100644 --- a/arch/x86/kernel/head_64.S +++ b/arch/x86/kernel/head_64.S @@ -38,7 +38,6 @@ #define pud_index(x) (((x) >> PUD_SHIFT) & (PTRS_PER_PUD-1)) L4_PAGE_OFFSET = pgd_index(__PAGE_OFFSET) -L3_PAGE_OFFSET = pud_index(__PAGE_OFFSET) L4_START_KERNEL = pgd_index(__START_KERNEL_map) L3_START_KERNEL = pud_index(__START_KERNEL_map) diff --git a/arch/x86/kernel/hpet.c b/arch/x86/kernel/hpet.c index b8e6ff5cd5d0..be0ebbb6d1d1 100644 --- a/arch/x86/kernel/hpet.c +++ b/arch/x86/kernel/hpet.c @@ -12,6 +12,7 @@ #include <linux/pm.h> #include <linux/io.h> +#include <asm/cpufeature.h> #include <asm/irqdomain.h> #include <asm/fixmap.h> #include <asm/hpet.h> diff --git a/arch/x86/kernel/mcount_64.S b/arch/x86/kernel/mcount_64.S index 87e1762e2bca..ed48a9f465f8 100644 --- a/arch/x86/kernel/mcount_64.S +++ b/arch/x86/kernel/mcount_64.S @@ -168,12 +168,14 @@ GLOBAL(ftrace_call) restore_mcount_regs /* - * The copied trampoline must call ftrace_return as it + * The copied trampoline must call ftrace_epilogue as it * still may need to call the function graph tracer. + * + * The code up to this label is copied into trampolines so + * think twice before adding any new code or changing the + * layout here. */ -GLOBAL(ftrace_caller_end) - -GLOBAL(ftrace_return) +GLOBAL(ftrace_epilogue) #ifdef CONFIG_FUNCTION_GRAPH_TRACER GLOBAL(ftrace_graph_call) @@ -244,14 +246,14 @@ GLOBAL(ftrace_regs_call) popfq /* - * As this jmp to ftrace_return can be a short jump + * As this jmp to ftrace_epilogue can be a short jump * it must not be copied into the trampoline. * The trampoline will add the code to jump * to the return. */ GLOBAL(ftrace_regs_caller_end) - jmp ftrace_return + jmp ftrace_epilogue END(ftrace_regs_caller) diff --git a/arch/x86/kernel/msr.c b/arch/x86/kernel/msr.c index 64f9616f93f1..7f3550acde1b 100644 --- a/arch/x86/kernel/msr.c +++ b/arch/x86/kernel/msr.c @@ -40,7 +40,7 @@ #include <linux/uaccess.h> #include <linux/gfp.h> -#include <asm/processor.h> +#include <asm/cpufeature.h> #include <asm/msr.h> static struct class *msr_class; diff --git a/arch/x86/kernel/process.c b/arch/x86/kernel/process.c index 9decee2bfdbe..2915d54e9dd5 100644 --- a/arch/x86/kernel/process.c +++ b/arch/x86/kernel/process.c @@ -57,6 +57,9 @@ __visible DEFINE_PER_CPU_SHARED_ALIGNED(struct tss_struct, cpu_tss) = { */ .io_bitmap = { [0 ... IO_BITMAP_LONGS] = ~0 }, #endif +#ifdef CONFIG_X86_32 + .SYSENTER_stack_canary = STACK_END_MAGIC, +#endif }; EXPORT_PER_CPU_SYMBOL(cpu_tss); diff --git a/arch/x86/kernel/signal.c b/arch/x86/kernel/signal.c index cb6282c3638f..548ddf7d6fd2 100644 --- a/arch/x86/kernel/signal.c +++ b/arch/x86/kernel/signal.c @@ -61,7 +61,38 @@ regs->seg = GET_SEG(seg) | 3; \ } while (0) -int restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc) +#ifdef CONFIG_X86_64 +/* + * If regs->ss will cause an IRET fault, change it. Otherwise leave it + * alone. Using this generally makes no sense unless + * user_64bit_mode(regs) would return true. + */ +static void force_valid_ss(struct pt_regs *regs) +{ + u32 ar; + asm volatile ("lar %[old_ss], %[ar]\n\t" + "jz 1f\n\t" /* If invalid: */ + "xorl %[ar], %[ar]\n\t" /* set ar = 0 */ + "1:" + : [ar] "=r" (ar) + : [old_ss] "rm" ((u16)regs->ss)); + + /* + * For a valid 64-bit user context, we need DPL 3, type + * read-write data or read-write exp-down data, and S and P + * set. We can't use VERW because VERW doesn't check the + * P bit. + */ + ar &= AR_DPL_MASK | AR_S | AR_P | AR_TYPE_MASK; + if (ar != (AR_DPL3 | AR_S | AR_P | AR_TYPE_RWDATA) && + ar != (AR_DPL3 | AR_S | AR_P | AR_TYPE_RWDATA_EXPDOWN)) + regs->ss = __USER_DS; +} +#endif + +static int restore_sigcontext(struct pt_regs *regs, + struct sigcontext __user *sc, + unsigned long uc_flags) { unsigned long buf_val; void __user *buf; @@ -94,15 +125,18 @@ int restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc) COPY(r15); #endif /* CONFIG_X86_64 */ -#ifdef CONFIG_X86_32 COPY_SEG_CPL3(cs); COPY_SEG_CPL3(ss); -#else /* !CONFIG_X86_32 */ - /* Kernel saves and restores only the CS segment register on signals, - * which is the bare minimum needed to allow mixed 32/64-bit code. - * App's signal handler can save/restore other segments if needed. */ - COPY_SEG_CPL3(cs); -#endif /* CONFIG_X86_32 */ + +#ifdef CONFIG_X86_64 + /* + * Fix up SS if needed for the benefit of old DOSEMU and + * CRIU. + */ + if (unlikely(!(uc_flags & UC_STRICT_RESTORE_SS) && + user_64bit_mode(regs))) + force_valid_ss(regs); +#endif get_user_ex(tmpflags, &sc->flags); regs->flags = (regs->flags & ~FIX_EFLAGS) | (tmpflags & FIX_EFLAGS); @@ -165,6 +199,7 @@ int setup_sigcontext(struct sigcontext __user *sc, void __user *fpstate, put_user_ex(regs->cs, &sc->cs); put_user_ex(0, &sc->gs); put_user_ex(0, &sc->fs); + put_user_ex(regs->ss, &sc->ss); #endif /* CONFIG_X86_32 */ put_user_ex(fpstate, &sc->fpstate); @@ -403,6 +438,21 @@ static int __setup_rt_frame(int sig, struct ksignal *ksig, return 0; } #else /* !CONFIG_X86_32 */ +static unsigned long frame_uc_flags(struct pt_regs *regs) +{ + unsigned long flags; + + if (cpu_has_xsave) + flags = UC_FP_XSTATE | UC_SIGCONTEXT_SS; + else + flags = UC_SIGCONTEXT_SS; + + if (likely(user_64bit_mode(regs))) + flags |= UC_STRICT_RESTORE_SS; + + return flags; +} + static int __setup_rt_frame(int sig, struct ksignal *ksig, sigset_t *set, struct pt_regs *regs) { @@ -422,10 +472,7 @@ static int __setup_rt_frame(int sig, struct ksignal *ksig, put_user_try { /* Create the ucontext. */ - if (cpu_has_xsave) - put_user_ex(UC_FP_XSTATE, &frame->uc.uc_flags); - else - put_user_ex(0, &frame->uc.uc_flags); + put_user_ex(frame_uc_flags(regs), &frame->uc.uc_flags); put_user_ex(0, &frame->uc.uc_link); save_altstack_ex(&frame->uc.uc_stack, regs->sp); @@ -459,10 +506,28 @@ static int __setup_rt_frame(int sig, struct ksignal *ksig, regs->sp = (unsigned long)frame; - /* Set up the CS register to run signal handlers in 64-bit mode, - even if the handler happens to be interrupting 32-bit code. */ + /* + * Set up the CS and SS registers to run signal handlers in + * 64-bit mode, even if the handler happens to be interrupting + * 32-bit or 16-bit code. + * + * SS is subtle. In 64-bit mode, we don't need any particular + * SS descriptor, but we do need SS to be valid. It's possible + * that the old SS is entirely bogus -- this can happen if the + * signal we're trying to deliver is #GP or #SS caused by a bad + * SS value. We also have a compatbility issue here: DOSEMU + * relies on the contents of the SS register indicating the + * SS value at the time of the signal, even though that code in + * DOSEMU predates sigreturn's ability to restore SS. (DOSEMU + * avoids relying on sigreturn to restore SS; instead it uses + * a trampoline.) So we do our best: if the old SS was valid, + * we keep it. Otherwise we replace it. + */ regs->cs = __USER_CS; + if (unlikely(regs->ss != __USER_DS)) + force_valid_ss(regs); + return 0; } #endif /* CONFIG_X86_32 */ @@ -489,10 +554,7 @@ static int x32_setup_rt_frame(struct ksignal *ksig, put_user_try { /* Create the ucontext. */ - if (cpu_has_xsave) - put_user_ex(UC_FP_XSTATE, &frame->uc.uc_flags); - else - put_user_ex(0, &frame->uc.uc_flags); + put_user_ex(frame_uc_flags(regs), &frame->uc.uc_flags); put_user_ex(0, &frame->uc.uc_link); compat_save_altstack_ex(&frame->uc.uc_stack, regs->sp); put_user_ex(0, &frame->uc.uc__pad0); @@ -554,7 +616,11 @@ asmlinkage unsigned long sys_sigreturn(void) set_current_blocked(&set); - if (restore_sigcontext(regs, &frame->sc)) + /* + * x86_32 has no uc_flags bits relevant to restore_sigcontext. + * Save a few cycles by skipping the __get_user. + */ + if (restore_sigcontext(regs, &frame->sc, 0)) goto badframe; return regs->ax; @@ -570,16 +636,19 @@ asmlinkage long sys_rt_sigreturn(void) struct pt_regs *regs = current_pt_regs(); struct rt_sigframe __user *frame; sigset_t set; + unsigned long uc_flags; frame = (struct rt_sigframe __user *)(regs->sp - sizeof(long)); if (!access_ok(VERIFY_READ, frame, sizeof(*frame))) goto badframe; if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set))) goto badframe; + if (__get_user(uc_flags, &frame->uc.uc_flags)) + goto badframe; set_current_blocked(&set); - if (restore_sigcontext(regs, &frame->uc.uc_mcontext)) + if (restore_sigcontext(regs, &frame->uc.uc_mcontext, uc_flags)) goto badframe; if (restore_altstack(&frame->uc.uc_stack)) @@ -692,12 +761,15 @@ handle_signal(struct ksignal *ksig, struct pt_regs *regs) static inline unsigned long get_nr_restart_syscall(const struct pt_regs *regs) { -#if defined(CONFIG_X86_32) || !defined(CONFIG_X86_64) +#ifdef CONFIG_X86_64 + if (is_ia32_task()) + return __NR_ia32_restart_syscall; +#endif +#ifdef CONFIG_X86_X32_ABI + return __NR_restart_syscall | (regs->orig_ax & __X32_SYSCALL_BIT); +#else return __NR_restart_syscall; -#else /* !CONFIG_X86_32 && CONFIG_X86_64 */ - return test_thread_flag(TIF_IA32) ? __NR_ia32_restart_syscall : - __NR_restart_syscall | (regs->orig_ax & __X32_SYSCALL_BIT); -#endif /* CONFIG_X86_32 || !CONFIG_X86_64 */ +#endif } /* @@ -763,6 +835,7 @@ asmlinkage long sys32_x32_rt_sigreturn(void) struct pt_regs *regs = current_pt_regs(); struct rt_sigframe_x32 __user *frame; sigset_t set; + unsigned long uc_flags; frame = (struct rt_sigframe_x32 __user *)(regs->sp - 8); @@ -770,10 +843,12 @@ asmlinkage long sys32_x32_rt_sigreturn(void) goto badframe; if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set))) goto badframe; + if (__get_user(uc_flags, &frame->uc.uc_flags)) + goto badframe; set_current_blocked(&set); - if (restore_sigcontext(regs, &frame->uc.uc_mcontext)) + if (restore_sigcontext(regs, &frame->uc.uc_mcontext, uc_flags)) goto badframe; if (compat_restore_altstack(&frame->uc.uc_stack)) diff --git a/arch/x86/kernel/traps.c b/arch/x86/kernel/traps.c index 211c11c7bba4..5c9ca2bb9fe9 100644 --- a/arch/x86/kernel/traps.c +++ b/arch/x86/kernel/traps.c @@ -83,30 +83,16 @@ gate_desc idt_table[NR_VECTORS] __page_aligned_bss; DECLARE_BITMAP(used_vectors, NR_VECTORS); EXPORT_SYMBOL_GPL(used_vectors); -static inline void conditional_sti(struct pt_regs *regs) +static inline void cond_local_irq_enable(struct pt_regs *regs) { if (regs->flags & X86_EFLAGS_IF) local_irq_enable(); } -static inline void preempt_conditional_sti(struct pt_regs *regs) -{ - preempt_count_inc(); - if (regs->flags & X86_EFLAGS_IF) - local_irq_enable(); -} - -static inline void conditional_cli(struct pt_regs *regs) -{ - if (regs->flags & X86_EFLAGS_IF) - local_irq_disable(); -} - -static inline void preempt_conditional_cli(struct pt_regs *regs) +static inline void cond_local_irq_disable(struct pt_regs *regs) { if (regs->flags & X86_EFLAGS_IF) local_irq_disable(); - preempt_count_dec(); } void ist_enter(struct pt_regs *regs) @@ -262,7 +248,6 @@ do_trap(int trapnr, int signr, char *str, struct pt_regs *regs, tsk->thread.error_code = error_code; tsk->thread.trap_nr = trapnr; -#ifdef CONFIG_X86_64 if (show_unhandled_signals && unhandled_signal(tsk, signr) && printk_ratelimit()) { pr_info("%s[%d] trap %s ip:%lx sp:%lx error:%lx", @@ -271,7 +256,6 @@ do_trap(int trapnr, int signr, char *str, struct pt_regs *regs, print_vma_addr(" in ", regs->ip); pr_cont("\n"); } -#endif force_sig_info(signr, info ?: SEND_SIG_PRIV, tsk); } @@ -286,7 +270,7 @@ static void do_error_trap(struct pt_regs *regs, long error_code, char *str, if (notify_die(DIE_TRAP, str, regs, error_code, trapnr, signr) != NOTIFY_STOP) { - conditional_sti(regs); + cond_local_irq_enable(regs); do_trap(trapnr, signr, str, regs, error_code, fill_trap_info(regs, signr, trapnr, &info)); } @@ -368,7 +352,7 @@ dotraplinkage void do_bounds(struct pt_regs *regs, long error_code) if (notify_die(DIE_TRAP, "bounds", regs, error_code, X86_TRAP_BR, SIGSEGV) == NOTIFY_STOP) return; - conditional_sti(regs); + cond_local_irq_enable(regs); if (!user_mode(regs)) die("bounds", regs, error_code); @@ -443,7 +427,7 @@ do_general_protection(struct pt_regs *regs, long error_code) struct task_struct *tsk; RCU_LOCKDEP_WARN(!rcu_is_watching(), "entry code didn't wake RCU"); - conditional_sti(regs); + cond_local_irq_enable(regs); if (v8086_mode(regs)) { local_irq_enable(); @@ -517,9 +501,11 @@ dotraplinkage void notrace do_int3(struct pt_regs *regs, long error_code) * as we may switch to the interrupt stack. */ debug_stack_usage_inc(); - preempt_conditional_sti(regs); + preempt_disable(); + cond_local_irq_enable(regs); do_trap(X86_TRAP_BP, SIGTRAP, "int3", regs, error_code, NULL); - preempt_conditional_cli(regs); + cond_local_irq_disable(regs); + preempt_enable_no_resched(); debug_stack_usage_dec(); exit: ist_exit(regs); @@ -571,6 +557,29 @@ struct bad_iret_stack *fixup_bad_iret(struct bad_iret_stack *s) NOKPROBE_SYMBOL(fixup_bad_iret); #endif +static bool is_sysenter_singlestep(struct pt_regs *regs) +{ + /* + * We don't try for precision here. If we're anywhere in the region of + * code that can be single-stepped in the SYSENTER entry path, then + * assume that this is a useless single-step trap due to SYSENTER + * being invoked with TF set. (We don't know in advance exactly + * which instructions will be hit because BTF could plausibly + * be set.) + */ +#ifdef CONFIG_X86_32 + return (regs->ip - (unsigned long)__begin_SYSENTER_singlestep_region) < + (unsigned long)__end_SYSENTER_singlestep_region - + (unsigned long)__begin_SYSENTER_singlestep_region; +#elif defined(CONFIG_IA32_EMULATION) + return (regs->ip - (unsigned long)entry_SYSENTER_compat) < + (unsigned long)__end_entry_SYSENTER_compat - + (unsigned long)entry_SYSENTER_compat; +#else + return false; +#endif +} + /* * Our handling of the processor debug registers is non-trivial. * We do not clear them on entry and exit from the kernel. Therefore @@ -605,11 +614,42 @@ dotraplinkage void do_debug(struct pt_regs *regs, long error_code) ist_enter(regs); get_debugreg(dr6, 6); + /* + * The Intel SDM says: + * + * Certain debug exceptions may clear bits 0-3. The remaining + * contents of the DR6 register are never cleared by the + * processor. To avoid confusion in identifying debug + * exceptions, debug handlers should clear the register before + * returning to the interrupted task. + * + * Keep it simple: clear DR6 immediately. + */ + set_debugreg(0, 6); /* Filter out all the reserved bits which are preset to 1 */ dr6 &= ~DR6_RESERVED; /* + * The SDM says "The processor clears the BTF flag when it + * generates a debug exception." Clear TIF_BLOCKSTEP to keep + * TIF_BLOCKSTEP in sync with the hardware BTF flag. + */ + clear_tsk_thread_flag(tsk, TIF_BLOCKSTEP); + + if (unlikely(!user_mode(regs) && (dr6 & DR_STEP) && + is_sysenter_singlestep(regs))) { + dr6 &= ~DR_STEP; + if (!dr6) + goto exit; + /* + * else we might have gotten a single-step trap and hit a + * watchpoint at the same time, in which case we should fall + * through and handle the watchpoint. + */ + } + + /* * If dr6 has no reason to give us about the origin of this trap, * then it's very likely the result of an icebp/int01 trap. * User wants a sigtrap for that. @@ -617,18 +657,10 @@ dotraplinkage void do_debug(struct pt_regs *regs, long error_code) if (!dr6 && user_mode(regs)) user_icebp = 1; - /* Catch kmemcheck conditions first of all! */ + /* Catch kmemcheck conditions! */ if ((dr6 & DR_STEP) && kmemcheck_trap(regs)) goto exit; - /* DR6 may or may not be cleared by the CPU */ - set_debugreg(0, 6); - - /* - * The processor cleared BTF, so don't mark that we need it set. - */ - clear_tsk_thread_flag(tsk, TIF_BLOCKSTEP); - /* Store the virtualized DR6 value */ tsk->thread.debugreg6 = dr6; @@ -648,24 +680,25 @@ dotraplinkage void do_debug(struct pt_regs *regs, long error_code) debug_stack_usage_inc(); /* It's safe to allow irq's after DR6 has been saved */ - preempt_conditional_sti(regs); + preempt_disable(); + cond_local_irq_enable(regs); if (v8086_mode(regs)) { handle_vm86_trap((struct kernel_vm86_regs *) regs, error_code, X86_TRAP_DB); - preempt_conditional_cli(regs); + cond_local_irq_disable(regs); + preempt_enable_no_resched(); debug_stack_usage_dec(); goto exit; } - /* - * Single-stepping through system calls: ignore any exceptions in - * kernel space, but re-enable TF when returning to user mode. - * - * We already checked v86 mode above, so we can check for kernel mode - * by just checking the CPL of CS. - */ - if ((dr6 & DR_STEP) && !user_mode(regs)) { + if (WARN_ON_ONCE((dr6 & DR_STEP) && !user_mode(regs))) { + /* + * Historical junk that used to handle SYSENTER single-stepping. + * This should be unreachable now. If we survive for a while + * without anyone hitting this warning, we'll turn this into + * an oops. + */ tsk->thread.debugreg6 &= ~DR_STEP; set_tsk_thread_flag(tsk, TIF_SINGLESTEP); regs->flags &= ~X86_EFLAGS_TF; @@ -673,10 +706,19 @@ dotraplinkage void do_debug(struct pt_regs *regs, long error_code) si_code = get_si_code(tsk->thread.debugreg6); if (tsk->thread.debugreg6 & (DR_STEP | DR_TRAP_BITS) || user_icebp) send_sigtrap(tsk, regs, error_code, si_code); - preempt_conditional_cli(regs); + cond_local_irq_disable(regs); + preempt_enable_no_resched(); debug_stack_usage_dec(); exit: +#if defined(CONFIG_X86_32) + /* + * This is the most likely code path that involves non-trivial use + * of the SYSENTER stack. Check that we haven't overrun it. + */ + WARN(this_cpu_read(cpu_tss.SYSENTER_stack_canary) != STACK_END_MAGIC, + "Overran or corrupted SYSENTER stack\n"); +#endif ist_exit(regs); } NOKPROBE_SYMBOL(do_debug); @@ -696,7 +738,7 @@ static void math_error(struct pt_regs *regs, int error_code, int trapnr) if (notify_die(DIE_TRAP, str, regs, error_code, trapnr, SIGFPE) == NOTIFY_STOP) return; - conditional_sti(regs); + cond_local_irq_enable(regs); if (!user_mode(regs)) { if (!fixup_exception(regs, trapnr)) { @@ -743,7 +785,7 @@ do_simd_coprocessor_error(struct pt_regs *regs, long error_code) dotraplinkage void do_spurious_interrupt_bug(struct pt_regs *regs, long error_code) { - conditional_sti(regs); + cond_local_irq_enable(regs); } dotraplinkage void @@ -756,7 +798,7 @@ do_device_not_available(struct pt_regs *regs, long error_code) if (read_cr0() & X86_CR0_EM) { struct math_emu_info info = { }; - conditional_sti(regs); + cond_local_irq_enable(regs); info.regs = regs; math_emulate(&info); @@ -765,7 +807,7 @@ do_device_not_available(struct pt_regs *regs, long error_code) #endif fpu__restore(¤t->thread.fpu); /* interrupts still off */ #ifdef CONFIG_X86_32 - conditional_sti(regs); + cond_local_irq_enable(regs); #endif } NOKPROBE_SYMBOL(do_device_not_available); @@ -868,7 +910,7 @@ void __init trap_init(void) #endif #ifdef CONFIG_X86_32 - set_system_trap_gate(IA32_SYSCALL_VECTOR, entry_INT80_32); + set_system_intr_gate(IA32_SYSCALL_VECTOR, entry_INT80_32); set_bit(IA32_SYSCALL_VECTOR, used_vectors); #endif diff --git a/arch/x86/kernel/verify_cpu.S b/arch/x86/kernel/verify_cpu.S index 07efb35ee4bc..014ea59aa153 100644 --- a/arch/x86/kernel/verify_cpu.S +++ b/arch/x86/kernel/verify_cpu.S @@ -30,7 +30,7 @@ * appropriately. Either display a message or halt. */ -#include <asm/cpufeature.h> +#include <asm/cpufeatures.h> #include <asm/msr-index.h> verify_cpu: diff --git a/arch/x86/kernel/vm86_32.c b/arch/x86/kernel/vm86_32.c index e574b8546518..3dce1ca0a653 100644 --- a/arch/x86/kernel/vm86_32.c +++ b/arch/x86/kernel/vm86_32.c @@ -362,7 +362,7 @@ static long do_sys_vm86(struct vm86plus_struct __user *user_vm86, bool plus) /* make room for real-mode segments */ tsk->thread.sp0 += 16; - if (static_cpu_has_safe(X86_FEATURE_SEP)) + if (static_cpu_has(X86_FEATURE_SEP)) tsk->thread.sysenter_cs = 0; load_sp0(tss, &tsk->thread); diff --git a/arch/x86/kernel/vmlinux.lds.S b/arch/x86/kernel/vmlinux.lds.S index fe133b710bef..5af9958cbdb6 100644 --- a/arch/x86/kernel/vmlinux.lds.S +++ b/arch/x86/kernel/vmlinux.lds.S @@ -192,6 +192,17 @@ SECTIONS :init #endif + /* + * Section for code used exclusively before alternatives are run. All + * references to such code must be patched out by alternatives, normally + * by using X86_FEATURE_ALWAYS CPU feature bit. + * + * See static_cpu_has() for an example. + */ + .altinstr_aux : AT(ADDR(.altinstr_aux) - LOAD_OFFSET) { + *(.altinstr_aux) + } + INIT_DATA_SECTION(16) .x86_cpu_dev.init : AT(ADDR(.x86_cpu_dev.init) - LOAD_OFFSET) { |
