diff options
Diffstat (limited to 'arch/x86/kernel')
30 files changed, 479 insertions, 491 deletions
diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile index ba89cabe5fcf..2a7c3afa62e2 100644 --- a/arch/x86/kernel/Makefile +++ b/arch/x86/kernel/Makefile @@ -102,9 +102,7 @@ obj-$(CONFIG_KEXEC_FILE) += kexec-bzimage64.o obj-$(CONFIG_CRASH_DUMP) += crash_dump_$(BITS).o obj-y += kprobes/ obj-$(CONFIG_MODULES) += module.o -ifeq ($(CONFIG_X86_32),y) -obj-$(CONFIG_DOUBLEFAULT) += doublefault_32.o -endif +obj-$(CONFIG_X86_32) += doublefault_32.o obj-$(CONFIG_KGDB) += kgdb.o obj-$(CONFIG_VM86) += vm86_32.o obj-$(CONFIG_EARLY_PRINTK) += early_printk.o diff --git a/arch/x86/kernel/apb_timer.c b/arch/x86/kernel/apb_timer.c index fe698f96617c..263eeaddb0aa 100644 --- a/arch/x86/kernel/apb_timer.c +++ b/arch/x86/kernel/apb_timer.c @@ -345,56 +345,3 @@ out_noapbt: apb_timer_block_enabled = 0; panic("failed to enable APB timer\n"); } - -/* called before apb_timer_enable, use early map */ -unsigned long apbt_quick_calibrate(void) -{ - int i, scale; - u64 old, new; - u64 t1, t2; - unsigned long khz = 0; - u32 loop, shift; - - apbt_set_mapping(); - dw_apb_clocksource_start(clocksource_apbt); - - /* check if the timer can count down, otherwise return */ - old = dw_apb_clocksource_read(clocksource_apbt); - i = 10000; - while (--i) { - if (old != dw_apb_clocksource_read(clocksource_apbt)) - break; - } - if (!i) - goto failed; - - /* count 16 ms */ - loop = (apbt_freq / 1000) << 4; - - /* restart the timer to ensure it won't get to 0 in the calibration */ - dw_apb_clocksource_start(clocksource_apbt); - - old = dw_apb_clocksource_read(clocksource_apbt); - old += loop; - - t1 = rdtsc(); - - do { - new = dw_apb_clocksource_read(clocksource_apbt); - } while (new < old); - - t2 = rdtsc(); - - shift = 5; - if (unlikely(loop >> shift == 0)) { - printk(KERN_INFO - "APBT TSC calibration failed, not enough resolution\n"); - return 0; - } - scale = (int)div_u64((t2 - t1), loop >> shift); - khz = (scale * (apbt_freq / 1000)) >> shift; - printk(KERN_INFO "TSC freq calculated by APB timer is %lu khz\n", khz); - return khz; -failed: - return 0; -} diff --git a/arch/x86/kernel/apic/apic.c b/arch/x86/kernel/apic/apic.c index e53dda210cd7..4b1d31be50b4 100644 --- a/arch/x86/kernel/apic/apic.c +++ b/arch/x86/kernel/apic/apic.c @@ -544,46 +544,20 @@ static struct clock_event_device lapic_clockevent = { }; static DEFINE_PER_CPU(struct clock_event_device, lapic_events); -static __init u32 hsx_deadline_rev(void) -{ - switch (boot_cpu_data.x86_stepping) { - case 0x02: return 0x3a; /* EP */ - case 0x04: return 0x0f; /* EX */ - } - - return ~0U; -} - -static __init u32 bdx_deadline_rev(void) -{ - switch (boot_cpu_data.x86_stepping) { - case 0x02: return 0x00000011; - case 0x03: return 0x0700000e; - case 0x04: return 0x0f00000c; - case 0x05: return 0x0e000003; - } - - return ~0U; -} - -static __init u32 skx_deadline_rev(void) -{ - switch (boot_cpu_data.x86_stepping) { - case 0x03: return 0x01000136; - case 0x04: return 0x02000014; - } +static const struct x86_cpu_id deadline_match[] __initconst = { + X86_MATCH_INTEL_FAM6_MODEL_STEPPINGS(HASWELL_X, X86_STEPPINGS(0x2, 0x2), 0x3a), /* EP */ + X86_MATCH_INTEL_FAM6_MODEL_STEPPINGS(HASWELL_X, X86_STEPPINGS(0x4, 0x4), 0x0f), /* EX */ - if (boot_cpu_data.x86_stepping > 4) - return 0; + X86_MATCH_INTEL_FAM6_MODEL( BROADWELL_X, 0x0b000020), - return ~0U; -} + X86_MATCH_INTEL_FAM6_MODEL_STEPPINGS(BROADWELL_D, X86_STEPPINGS(0x2, 0x2), 0x00000011), + X86_MATCH_INTEL_FAM6_MODEL_STEPPINGS(BROADWELL_D, X86_STEPPINGS(0x3, 0x3), 0x0700000e), + X86_MATCH_INTEL_FAM6_MODEL_STEPPINGS(BROADWELL_D, X86_STEPPINGS(0x4, 0x4), 0x0f00000c), + X86_MATCH_INTEL_FAM6_MODEL_STEPPINGS(BROADWELL_D, X86_STEPPINGS(0x5, 0x5), 0x0e000003), -static const struct x86_cpu_id deadline_match[] __initconst = { - X86_MATCH_INTEL_FAM6_MODEL( HASWELL_X, &hsx_deadline_rev), - X86_MATCH_INTEL_FAM6_MODEL( BROADWELL_X, 0x0b000020), - X86_MATCH_INTEL_FAM6_MODEL( BROADWELL_D, &bdx_deadline_rev), - X86_MATCH_INTEL_FAM6_MODEL( SKYLAKE_X, &skx_deadline_rev), + X86_MATCH_INTEL_FAM6_MODEL_STEPPINGS(SKYLAKE_X, X86_STEPPINGS(0x3, 0x3), 0x01000136), + X86_MATCH_INTEL_FAM6_MODEL_STEPPINGS(SKYLAKE_X, X86_STEPPINGS(0x4, 0x4), 0x02000014), + X86_MATCH_INTEL_FAM6_MODEL_STEPPINGS(SKYLAKE_X, X86_STEPPINGS(0x5, 0xf), 0), X86_MATCH_INTEL_FAM6_MODEL( HASWELL, 0x22), X86_MATCH_INTEL_FAM6_MODEL( HASWELL_L, 0x20), @@ -615,14 +589,7 @@ static __init bool apic_validate_deadline_timer(void) if (!m) return true; - /* - * Function pointers will have the MSB set due to address layout, - * immediate revisions will not. - */ - if ((long)m->driver_data < 0) - rev = ((u32 (*)(void))(m->driver_data))(); - else - rev = (u32)m->driver_data; + rev = (u32)m->driver_data; if (boot_cpu_data.microcode >= rev) return true; diff --git a/arch/x86/kernel/apic/io_apic.c b/arch/x86/kernel/apic/io_apic.c index 913c88617848..ce61e3e7d399 100644 --- a/arch/x86/kernel/apic/io_apic.c +++ b/arch/x86/kernel/apic/io_apic.c @@ -154,19 +154,6 @@ static inline bool mp_is_legacy_irq(int irq) return irq >= 0 && irq < nr_legacy_irqs(); } -/* - * Initialize all legacy IRQs and all pins on the first IOAPIC - * if we have legacy interrupt controller. Kernel boot option "pirq=" - * may rely on non-legacy pins on the first IOAPIC. - */ -static inline int mp_init_irq_at_boot(int ioapic, int irq) -{ - if (!nr_legacy_irqs()) - return 0; - - return ioapic == 0 || mp_is_legacy_irq(irq); -} - static inline struct irq_domain *mp_ioapic_irqdomain(int ioapic) { return ioapics[ioapic].irqdomain; diff --git a/arch/x86/kernel/apic/x2apic_uv_x.c b/arch/x86/kernel/apic/x2apic_uv_x.c index ad53b2abc859..69e70ed0f5e6 100644 --- a/arch/x86/kernel/apic/x2apic_uv_x.c +++ b/arch/x86/kernel/apic/x2apic_uv_x.c @@ -30,8 +30,6 @@ static enum uv_system_type uv_system_type; static int uv_hubbed_system; static int uv_hubless_system; static u64 gru_start_paddr, gru_end_paddr; -static u64 gru_dist_base, gru_first_node_paddr = -1LL, gru_last_node_paddr; -static u64 gru_dist_lmask, gru_dist_umask; static union uvh_apicid uvh_apicid; /* Unpack OEM/TABLE ID's to be NULL terminated strings */ @@ -48,11 +46,9 @@ static struct { unsigned int gnode_shift; } uv_cpuid; -int uv_min_hub_revision_id; -EXPORT_SYMBOL_GPL(uv_min_hub_revision_id); +static int uv_min_hub_revision_id; unsigned int uv_apicid_hibits; -EXPORT_SYMBOL_GPL(uv_apicid_hibits); static struct apic apic_x2apic_uv_x; static struct uv_hub_info_s uv_hub_info_node0; @@ -85,20 +81,7 @@ static unsigned long __init uv_early_read_mmr(unsigned long addr) static inline bool is_GRU_range(u64 start, u64 end) { - if (gru_dist_base) { - u64 su = start & gru_dist_umask; /* Upper (incl pnode) bits */ - u64 sl = start & gru_dist_lmask; /* Base offset bits */ - u64 eu = end & gru_dist_umask; - u64 el = end & gru_dist_lmask; - - /* Must reside completely within a single GRU range: */ - return (sl == gru_dist_base && el == gru_dist_base && - su >= gru_first_node_paddr && - su <= gru_last_node_paddr && - eu == su); - } else { - return start >= gru_start_paddr && end <= gru_end_paddr; - } + return start >= gru_start_paddr && end <= gru_end_paddr; } static bool uv_is_untracked_pat_range(u64 start, u64 end) @@ -385,11 +368,10 @@ int is_uv_hubbed(int uvtype) } EXPORT_SYMBOL_GPL(is_uv_hubbed); -int is_uv_hubless(int uvtype) +static int is_uv_hubless(int uvtype) { return (uv_hubless_system & uvtype); } -EXPORT_SYMBOL_GPL(is_uv_hubless); void **__uv_hub_info_list; EXPORT_SYMBOL_GPL(__uv_hub_info_list); @@ -417,12 +399,6 @@ static __initdata struct uv_gam_range_s *_gr_table; #define SOCK_EMPTY ((unsigned short)~0) -extern int uv_hub_info_version(void) -{ - return UV_HUB_INFO_VERSION; -} -EXPORT_SYMBOL(uv_hub_info_version); - /* Default UV memory block size is 2GB */ static unsigned long mem_block_size __initdata = (2UL << 30); @@ -590,12 +566,21 @@ static int uv_wakeup_secondary(int phys_apicid, unsigned long start_rip) static void uv_send_IPI_one(int cpu, int vector) { - unsigned long apicid; - int pnode; + unsigned long apicid = per_cpu(x86_cpu_to_apicid, cpu); + int pnode = uv_apicid_to_pnode(apicid); + unsigned long dmode, val; + + if (vector == NMI_VECTOR) + dmode = dest_NMI; + else + dmode = dest_Fixed; + + val = (1UL << UVH_IPI_INT_SEND_SHFT) | + ((apicid | uv_apicid_hibits) << UVH_IPI_INT_APIC_ID_SHFT) | + (dmode << UVH_IPI_INT_DELIVERY_MODE_SHFT) | + (vector << UVH_IPI_INT_VECTOR_SHFT); - apicid = per_cpu(x86_cpu_to_apicid, cpu); - pnode = uv_apicid_to_pnode(apicid); - uv_hub_send_ipi(pnode, apicid, vector); + uv_write_global_mmr64(pnode, UVH_IPI_INT, val); } static void uv_send_IPI_mask(const struct cpumask *mask, int vector) @@ -797,42 +782,6 @@ static __init void map_high(char *id, unsigned long base, int pshift, int bshift init_extra_mapping_wb(paddr, bytes); } -static __init void map_gru_distributed(unsigned long c) -{ - union uvh_rh_gam_gru_overlay_config_mmr_u gru; - u64 paddr; - unsigned long bytes; - int nid; - - gru.v = c; - - /* Only base bits 42:28 relevant in dist mode */ - gru_dist_base = gru.v & 0x000007fff0000000UL; - if (!gru_dist_base) { - pr_info("UV: Map GRU_DIST base address NULL\n"); - return; - } - - bytes = 1UL << UVH_RH_GAM_GRU_OVERLAY_CONFIG_MMR_BASE_SHFT; - gru_dist_lmask = ((1UL << uv_hub_info->m_val) - 1) & ~(bytes - 1); - gru_dist_umask = ~((1UL << uv_hub_info->m_val) - 1); - gru_dist_base &= gru_dist_lmask; /* Clear bits above M */ - - for_each_online_node(nid) { - paddr = ((u64)uv_node_to_pnode(nid) << uv_hub_info->m_val) | - gru_dist_base; - init_extra_mapping_wb(paddr, bytes); - gru_first_node_paddr = min(paddr, gru_first_node_paddr); - gru_last_node_paddr = max(paddr, gru_last_node_paddr); - } - - /* Save upper (63:M) bits of address only for is_GRU_range */ - gru_first_node_paddr &= gru_dist_umask; - gru_last_node_paddr &= gru_dist_umask; - - pr_debug("UV: Map GRU_DIST base 0x%016llx 0x%016llx - 0x%016llx\n", gru_dist_base, gru_first_node_paddr, gru_last_node_paddr); -} - static __init void map_gru_high(int max_pnode) { union uvh_rh_gam_gru_overlay_config_mmr_u gru; @@ -846,12 +795,6 @@ static __init void map_gru_high(int max_pnode) return; } - /* Only UV3 has distributed GRU mode */ - if (is_uv3_hub() && gru.s3.mode) { - map_gru_distributed(gru.v); - return; - } - base = (gru.v & mask) >> shift; map_high("GRU", base, shift, shift, max_pnode, map_wb); gru_start_paddr = ((u64)base << shift); diff --git a/arch/x86/kernel/audit_64.c b/arch/x86/kernel/audit_64.c index e1efe44ebefc..83d9cad4e68b 100644 --- a/arch/x86/kernel/audit_64.c +++ b/arch/x86/kernel/audit_64.c @@ -3,6 +3,7 @@ #include <linux/types.h> #include <linux/audit.h> #include <asm/unistd.h> +#include <asm/audit.h> static unsigned dir_class[] = { #include <asm-generic/audit_dir_write.h> @@ -41,7 +42,6 @@ int audit_classify_arch(int arch) int audit_classify_syscall(int abi, unsigned syscall) { #ifdef CONFIG_IA32_EMULATION - extern int ia32_classify_syscall(unsigned); if (abi == AUDIT_ARCH_I386) return ia32_classify_syscall(syscall); #endif diff --git a/arch/x86/kernel/cpu/amd.c b/arch/x86/kernel/cpu/amd.c index c36e89930965..d4806eac9325 100644 --- a/arch/x86/kernel/cpu/amd.c +++ b/arch/x86/kernel/cpu/amd.c @@ -1145,8 +1145,7 @@ static const int amd_erratum_383[] = /* #1054: Instructions Retired Performance Counter May Be Inaccurate */ static const int amd_erratum_1054[] = - AMD_OSVW_ERRATUM(0, AMD_MODEL_RANGE(0x17, 0, 0, 0x2f, 0xf)); - + AMD_LEGACY_ERRATUM(AMD_MODEL_RANGE(0x17, 0, 0, 0x2f, 0xf)); static bool cpu_has_amd_erratum(struct cpuinfo_x86 *cpu, const int *erratum) { diff --git a/arch/x86/kernel/cpu/match.c b/arch/x86/kernel/cpu/match.c index d3482eb43ff3..ad6776081e60 100644 --- a/arch/x86/kernel/cpu/match.c +++ b/arch/x86/kernel/cpu/match.c @@ -39,13 +39,18 @@ const struct x86_cpu_id *x86_match_cpu(const struct x86_cpu_id *match) const struct x86_cpu_id *m; struct cpuinfo_x86 *c = &boot_cpu_data; - for (m = match; m->vendor | m->family | m->model | m->feature; m++) { + for (m = match; + m->vendor | m->family | m->model | m->steppings | m->feature; + m++) { if (m->vendor != X86_VENDOR_ANY && c->x86_vendor != m->vendor) continue; if (m->family != X86_FAMILY_ANY && c->x86 != m->family) continue; if (m->model != X86_MODEL_ANY && c->x86_model != m->model) continue; + if (m->steppings != X86_STEPPING_ANY && + !(BIT(c->x86_stepping) & m->steppings)) + continue; if (m->feature != X86_FEATURE_ANY && !cpu_has(c, m->feature)) continue; return m; diff --git a/arch/x86/kernel/cpu/mce/core.c b/arch/x86/kernel/cpu/mce/core.c index 54165f3569e8..e9265e2f28c9 100644 --- a/arch/x86/kernel/cpu/mce/core.c +++ b/arch/x86/kernel/cpu/mce/core.c @@ -42,6 +42,8 @@ #include <linux/export.h> #include <linux/jump_label.h> #include <linux/set_memory.h> +#include <linux/task_work.h> +#include <linux/hardirq.h> #include <asm/intel-family.h> #include <asm/processor.h> @@ -1086,23 +1088,6 @@ static void mce_clear_state(unsigned long *toclear) } } -static int do_memory_failure(struct mce *m) -{ - int flags = MF_ACTION_REQUIRED; - int ret; - - pr_err("Uncorrected hardware memory error in user-access at %llx", m->addr); - if (!(m->mcgstatus & MCG_STATUS_RIPV)) - flags |= MF_MUST_KILL; - ret = memory_failure(m->addr >> PAGE_SHIFT, flags); - if (ret) - pr_err("Memory error not recovered"); - else - set_mce_nospec(m->addr >> PAGE_SHIFT); - return ret; -} - - /* * Cases where we avoid rendezvous handler timeout: * 1) If this CPU is offline. @@ -1204,6 +1189,29 @@ static void __mc_scan_banks(struct mce *m, struct mce *final, *m = *final; } +static void kill_me_now(struct callback_head *ch) +{ + force_sig(SIGBUS); +} + +static void kill_me_maybe(struct callback_head *cb) +{ + struct task_struct *p = container_of(cb, struct task_struct, mce_kill_me); + int flags = MF_ACTION_REQUIRED; + + pr_err("Uncorrected hardware memory error in user-access at %llx", p->mce_addr); + if (!(p->mce_status & MCG_STATUS_RIPV)) + flags |= MF_MUST_KILL; + + if (!memory_failure(p->mce_addr >> PAGE_SHIFT, flags)) { + set_mce_nospec(p->mce_addr >> PAGE_SHIFT); + return; + } + + pr_err("Memory error not recovered"); + kill_me_now(cb); +} + /* * The actual machine check handler. This only handles real * exceptions when something got corrupted coming in through int 18. @@ -1222,7 +1230,7 @@ static void __mc_scan_banks(struct mce *m, struct mce *final, * backing the user stack, tracing that reads the user stack will cause * potentially infinite recursion. */ -void notrace do_machine_check(struct pt_regs *regs, long error_code) +void noinstr do_machine_check(struct pt_regs *regs, long error_code) { DECLARE_BITMAP(valid_banks, MAX_NR_BANKS); DECLARE_BITMAP(toclear, MAX_NR_BANKS); @@ -1259,7 +1267,7 @@ void notrace do_machine_check(struct pt_regs *regs, long error_code) if (__mc_check_crashing_cpu(cpu)) return; - ist_enter(regs); + nmi_enter(); this_cpu_inc(mce_exception_count); @@ -1352,23 +1360,24 @@ void notrace do_machine_check(struct pt_regs *regs, long error_code) /* Fault was in user mode and we need to take some action */ if ((m.cs & 3) == 3) { - ist_begin_non_atomic(regs); - local_irq_enable(); - - if (kill_it || do_memory_failure(&m)) - force_sig(SIGBUS); - local_irq_disable(); - ist_end_non_atomic(); + /* If this triggers there is no way to recover. Die hard. */ + BUG_ON(!on_thread_stack() || !user_mode(regs)); + + current->mce_addr = m.addr; + current->mce_status = m.mcgstatus; + current->mce_kill_me.func = kill_me_maybe; + if (kill_it) + current->mce_kill_me.func = kill_me_now; + task_work_add(current, ¤t->mce_kill_me, true); } else { if (!fixup_exception(regs, X86_TRAP_MC, error_code, 0)) mce_panic("Failed kernel mode recovery", &m, msg); } out_ist: - ist_exit(regs); + nmi_exit(); } EXPORT_SYMBOL_GPL(do_machine_check); -NOKPROBE_SYMBOL(do_machine_check); #ifndef CONFIG_MEMORY_FAILURE int memory_failure(unsigned long pfn, int flags) diff --git a/arch/x86/kernel/cpu/mce/p5.c b/arch/x86/kernel/cpu/mce/p5.c index 4ae6df556526..5ee94aa1b766 100644 --- a/arch/x86/kernel/cpu/mce/p5.c +++ b/arch/x86/kernel/cpu/mce/p5.c @@ -7,6 +7,7 @@ #include <linux/kernel.h> #include <linux/types.h> #include <linux/smp.h> +#include <linux/hardirq.h> #include <asm/processor.h> #include <asm/traps.h> @@ -24,7 +25,7 @@ static void pentium_machine_check(struct pt_regs *regs, long error_code) { u32 loaddr, hi, lotype; - ist_enter(regs); + nmi_enter(); rdmsr(MSR_IA32_P5_MC_ADDR, loaddr, hi); rdmsr(MSR_IA32_P5_MC_TYPE, lotype, hi); @@ -39,7 +40,7 @@ static void pentium_machine_check(struct pt_regs *regs, long error_code) add_taint(TAINT_MACHINE_CHECK, LOCKDEP_NOW_UNRELIABLE); - ist_exit(regs); + nmi_exit(); } /* Set up machine check reporting for processors with Intel style MCE: */ diff --git a/arch/x86/kernel/cpu/mce/winchip.c b/arch/x86/kernel/cpu/mce/winchip.c index a30ea13cccc2..b3938c195365 100644 --- a/arch/x86/kernel/cpu/mce/winchip.c +++ b/arch/x86/kernel/cpu/mce/winchip.c @@ -6,6 +6,7 @@ #include <linux/interrupt.h> #include <linux/kernel.h> #include <linux/types.h> +#include <linux/hardirq.h> #include <asm/processor.h> #include <asm/traps.h> @@ -18,12 +19,12 @@ /* Machine check handler for WinChip C6: */ static void winchip_machine_check(struct pt_regs *regs, long error_code) { - ist_enter(regs); + nmi_enter(); pr_emerg("CPU0: Machine Check Exception.\n"); add_taint(TAINT_MACHINE_CHECK, LOCKDEP_NOW_UNRELIABLE); - ist_exit(regs); + nmi_exit(); } /* Set up machine check reporting on the Winchip C6 series */ diff --git a/arch/x86/kernel/cpu/perfctr-watchdog.c b/arch/x86/kernel/cpu/perfctr-watchdog.c index 9556930cd8c1..a5ee607a3b89 100644 --- a/arch/x86/kernel/cpu/perfctr-watchdog.c +++ b/arch/x86/kernel/cpu/perfctr-watchdog.c @@ -63,6 +63,10 @@ static inline unsigned int nmi_perfctr_msr_to_bit(unsigned int msr) case 15: return msr - MSR_P4_BPU_PERFCTR0; } + fallthrough; + case X86_VENDOR_ZHAOXIN: + case X86_VENDOR_CENTAUR: + return msr - MSR_ARCH_PERFMON_PERFCTR0; } return 0; } @@ -92,6 +96,10 @@ static inline unsigned int nmi_evntsel_msr_to_bit(unsigned int msr) case 15: return msr - MSR_P4_BSU_ESCR0; } + fallthrough; + case X86_VENDOR_ZHAOXIN: + case X86_VENDOR_CENTAUR: + return msr - MSR_ARCH_PERFMON_EVENTSEL0; } return 0; diff --git a/arch/x86/kernel/dumpstack_32.c b/arch/x86/kernel/dumpstack_32.c index 8e3a8fedfa4d..722fd712e1cf 100644 --- a/arch/x86/kernel/dumpstack_32.c +++ b/arch/x86/kernel/dumpstack_32.c @@ -87,7 +87,6 @@ static bool in_softirq_stack(unsigned long *stack, struct stack_info *info) static bool in_doublefault_stack(unsigned long *stack, struct stack_info *info) { -#ifdef CONFIG_DOUBLEFAULT struct cpu_entry_area *cea = get_cpu_entry_area(raw_smp_processor_id()); struct doublefault_stack *ss = &cea->doublefault_stack; @@ -103,9 +102,6 @@ static bool in_doublefault_stack(unsigned long *stack, struct stack_info *info) info->next_sp = (unsigned long *)this_cpu_read(cpu_tss_rw.x86_tss.sp); return true; -#else - return false; -#endif } diff --git a/arch/x86/kernel/e820.c b/arch/x86/kernel/e820.c index c5399e80c59c..4d13c57f370a 100644 --- a/arch/x86/kernel/e820.c +++ b/arch/x86/kernel/e820.c @@ -910,14 +910,6 @@ static int __init parse_memmap_one(char *p) return -EINVAL; if (!strncmp(p, "exactmap", 8)) { -#ifdef CONFIG_CRASH_DUMP - /* - * If we are doing a crash dump, we still need to know - * the real memory size before the original memory map is - * reset. - */ - saved_max_pfn = e820__end_of_ram_pfn(); -#endif e820_table->nr_entries = 0; userdef = 1; return 0; diff --git a/arch/x86/kernel/early_printk.c b/arch/x86/kernel/early_printk.c index 9b33904251a9..93fbdff2974f 100644 --- a/arch/x86/kernel/early_printk.c +++ b/arch/x86/kernel/early_printk.c @@ -15,12 +15,9 @@ #include <xen/hvc-console.h> #include <asm/pci-direct.h> #include <asm/fixmap.h> -#include <asm/intel-mid.h> #include <asm/pgtable.h> #include <linux/usb/ehci_def.h> #include <linux/usb/xhci-dbgp.h> -#include <linux/efi.h> -#include <asm/efi.h> #include <asm/pci_x86.h> /* Simple VGA output */ diff --git a/arch/x86/kernel/fpu/core.c b/arch/x86/kernel/fpu/core.c index 12c70840980e..06c818967bb6 100644 --- a/arch/x86/kernel/fpu/core.c +++ b/arch/x86/kernel/fpu/core.c @@ -291,15 +291,13 @@ void fpu__drop(struct fpu *fpu) } /* - * Clear FPU registers by setting them up from - * the init fpstate: + * Clear FPU registers by setting them up from the init fpstate. + * Caller must do fpregs_[un]lock() around it. */ -static inline void copy_init_fpstate_to_fpregs(void) +static inline void copy_init_fpstate_to_fpregs(u64 features_mask) { - fpregs_lock(); - if (use_xsave()) - copy_kernel_to_xregs(&init_fpstate.xsave, -1); + copy_kernel_to_xregs(&init_fpstate.xsave, features_mask); else if (static_cpu_has(X86_FEATURE_FXSR)) copy_kernel_to_fxregs(&init_fpstate.fxsave); else @@ -307,9 +305,6 @@ static inline void copy_init_fpstate_to_fpregs(void) if (boot_cpu_has(X86_FEATURE_OSPKE)) copy_init_pkru_to_fpregs(); - - fpregs_mark_activate(); - fpregs_unlock(); } /* @@ -318,18 +313,40 @@ static inline void copy_init_fpstate_to_fpregs(void) * Called by sys_execve(), by the signal handler code and by various * error paths. */ -void fpu__clear(struct fpu *fpu) +static void fpu__clear(struct fpu *fpu, bool user_only) { - WARN_ON_FPU(fpu != ¤t->thread.fpu); /* Almost certainly an anomaly */ + WARN_ON_FPU(fpu != ¤t->thread.fpu); - fpu__drop(fpu); + if (!static_cpu_has(X86_FEATURE_FPU)) { + fpu__drop(fpu); + fpu__initialize(fpu); + return; + } - /* - * Make sure fpstate is cleared and initialized. - */ - fpu__initialize(fpu); - if (static_cpu_has(X86_FEATURE_FPU)) - copy_init_fpstate_to_fpregs(); + fpregs_lock(); + + if (user_only) { + if (!fpregs_state_valid(fpu, smp_processor_id()) && + xfeatures_mask_supervisor()) + copy_kernel_to_xregs(&fpu->state.xsave, + xfeatures_mask_supervisor()); + copy_init_fpstate_to_fpregs(xfeatures_mask_user()); + } else { + copy_init_fpstate_to_fpregs(xfeatures_mask_all); + } + + fpregs_mark_activate(); + fpregs_unlock(); +} + +void fpu__clear_user_states(struct fpu *fpu) +{ + fpu__clear(fpu, true); +} + +void fpu__clear_all(struct fpu *fpu) +{ + fpu__clear(fpu, false); } /* diff --git a/arch/x86/kernel/fpu/init.c b/arch/x86/kernel/fpu/init.c index 6ce7e0a23268..61ddc3a5e5c2 100644 --- a/arch/x86/kernel/fpu/init.c +++ b/arch/x86/kernel/fpu/init.c @@ -224,7 +224,8 @@ static void __init fpu__init_system_xstate_size_legacy(void) */ u64 __init fpu__get_supported_xfeatures_mask(void) { - return XCNTXT_MASK; + return XFEATURE_MASK_USER_SUPPORTED | + XFEATURE_MASK_SUPERVISOR_SUPPORTED; } /* Legacy code to initialize eager fpu mode. */ diff --git a/arch/x86/kernel/fpu/regset.c b/arch/x86/kernel/fpu/regset.c index d652b939ccfb..bd1d0649f8ce 100644 --- a/arch/x86/kernel/fpu/regset.c +++ b/arch/x86/kernel/fpu/regset.c @@ -139,7 +139,7 @@ int xstateregs_set(struct task_struct *target, const struct user_regset *regset, } else { ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, xsave, 0, -1); if (!ret) - ret = validate_xstate_header(&xsave->header); + ret = validate_user_xstate_header(&xsave->header); } /* diff --git a/arch/x86/kernel/fpu/signal.c b/arch/x86/kernel/fpu/signal.c index 400a05e1c1c5..9393a445d73c 100644 --- a/arch/x86/kernel/fpu/signal.c +++ b/arch/x86/kernel/fpu/signal.c @@ -211,9 +211,9 @@ retry: } static inline void -sanitize_restored_xstate(union fpregs_state *state, - struct user_i387_ia32_struct *ia32_env, - u64 xfeatures, int fx_only) +sanitize_restored_user_xstate(union fpregs_state *state, + struct user_i387_ia32_struct *ia32_env, + u64 user_xfeatures, int fx_only) { struct xregs_state *xsave = &state->xsave; struct xstate_header *header = &xsave->header; @@ -226,13 +226,22 @@ sanitize_restored_xstate(union fpregs_state *state, */ /* - * Init the state that is not present in the memory - * layout and not enabled by the OS. + * 'user_xfeatures' might have bits clear which are + * set in header->xfeatures. This represents features that + * were in init state prior to a signal delivery, and need + * to be reset back to the init state. Clear any user + * feature bits which are set in the kernel buffer to get + * them back to the init state. + * + * Supervisor state is unchanged by input from userspace. + * Ensure supervisor state bits stay set and supervisor + * state is not modified. */ if (fx_only) header->xfeatures = XFEATURE_MASK_FPSSE; else - header->xfeatures &= xfeatures; + header->xfeatures &= user_xfeatures | + xfeatures_mask_supervisor(); } if (use_fxsr()) { @@ -252,16 +261,24 @@ sanitize_restored_xstate(union fpregs_state *state, */ static int copy_user_to_fpregs_zeroing(void __user *buf, u64 xbv, int fx_only) { + u64 init_bv; + int r; + if (use_xsave()) { if (fx_only) { - u64 init_bv = xfeatures_mask & ~XFEATURE_MASK_FPSSE; - copy_kernel_to_xregs(&init_fpstate.xsave, init_bv); - return copy_user_to_fxregs(buf); + init_bv = xfeatures_mask_user() & ~XFEATURE_MASK_FPSSE; + + r = copy_user_to_fxregs(buf); + if (!r) + copy_kernel_to_xregs(&init_fpstate.xsave, init_bv); + return r; } else { - u64 init_bv = xfeatures_mask & ~xbv; - if (unlikely(init_bv)) + init_bv = xfeatures_mask_user() & ~xbv; + + r = copy_user_to_xregs(buf, xbv); + if (!r && unlikely(init_bv)) copy_kernel_to_xregs(&init_fpstate.xsave, init_bv); - return copy_user_to_xregs(buf, xbv); + return r; } } else if (use_fxsr()) { return copy_user_to_fxregs(buf); @@ -277,7 +294,7 @@ static int __fpu__restore_sig(void __user *buf, void __user *buf_fx, int size) struct task_struct *tsk = current; struct fpu *fpu = &tsk->thread.fpu; struct user_i387_ia32_struct env; - u64 xfeatures = 0; + u64 user_xfeatures = 0; int fx_only = 0; int ret = 0; @@ -285,7 +302,7 @@ static int __fpu__restore_sig(void __user *buf, void __user *buf_fx, int size) IS_ENABLED(CONFIG_IA32_EMULATION)); if (!buf) { - fpu__clear(fpu); + fpu__clear_user_states(fpu); return 0; } @@ -310,32 +327,14 @@ static int __fpu__restore_sig(void __user *buf, void __user *buf_fx, int size) trace_x86_fpu_xstate_check_failed(fpu); } else { state_size = fx_sw_user.xstate_size; - xfeatures = fx_sw_user.xfeatures; + user_xfeatures = fx_sw_user.xfeatures; } } - /* - * The current state of the FPU registers does not matter. By setting - * TIF_NEED_FPU_LOAD unconditionally it is ensured that the our xstate - * is not modified on context switch and that the xstate is considered - * to be loaded again on return to userland (overriding last_cpu avoids - * the optimisation). - */ - set_thread_flag(TIF_NEED_FPU_LOAD); - __fpu_invalidate_fpregs_state(fpu); - if ((unsigned long)buf_fx % 64) fx_only = 1; - /* - * For 32-bit frames with fxstate, copy the fxstate so it can be - * reconstructed later. - */ - if (ia32_fxstate) { - ret = __copy_from_user(&env, buf, sizeof(env)); - if (ret) - goto err_out; - envp = &env; - } else { + + if (!ia32_fxstate) { /* * Attempt to restore the FPU registers directly from user * memory. For that to succeed, the user access cannot cause @@ -345,20 +344,65 @@ static int __fpu__restore_sig(void __user *buf, void __user *buf_fx, int size) */ fpregs_lock(); pagefault_disable(); - ret = copy_user_to_fpregs_zeroing(buf_fx, xfeatures, fx_only); + ret = copy_user_to_fpregs_zeroing(buf_fx, user_xfeatures, fx_only); pagefault_enable(); if (!ret) { + + /* + * Restore supervisor states: previous context switch + * etc has done XSAVES and saved the supervisor states + * in the kernel buffer from which they can be restored + * now. + * + * We cannot do a single XRSTORS here - which would + * be nice - because the rest of the FPU registers are + * being restored from a user buffer directly. The + * single XRSTORS happens below, when the user buffer + * has been copied to the kernel one. + */ + if (test_thread_flag(TIF_NEED_FPU_LOAD) && + xfeatures_mask_supervisor()) + copy_kernel_to_xregs(&fpu->state.xsave, + xfeatures_mask_supervisor()); fpregs_mark_activate(); fpregs_unlock(); return 0; } - fpregs_deactivate(fpu); fpregs_unlock(); + } else { + /* + * For 32-bit frames with fxstate, copy the fxstate so it can + * be reconstructed later. + */ + ret = __copy_from_user(&env, buf, sizeof(env)); + if (ret) + goto err_out; + envp = &env; } + /* + * By setting TIF_NEED_FPU_LOAD it is ensured that our xstate is + * not modified on context switch and that the xstate is considered + * to be loaded again on return to userland (overriding last_cpu avoids + * the optimisation). + */ + fpregs_lock(); + + if (!test_thread_flag(TIF_NEED_FPU_LOAD)) { + + /* + * Supervisor states are not modified by user space input. Save + * current supervisor states first and invalidate the FPU regs. + */ + if (xfeatures_mask_supervisor()) + copy_supervisor_to_kernel(&fpu->state.xsave); + set_thread_flag(TIF_NEED_FPU_LOAD); + } + __fpu_invalidate_fpregs_state(fpu); + fpregs_unlock(); if (use_xsave() && !fx_only) { - u64 init_bv = xfeatures_mask & ~xfeatures; + u64 init_bv = xfeatures_mask_user() & ~user_xfeatures; if (using_compacted_format()) { ret = copy_user_to_xstate(&fpu->state.xsave, buf_fx); @@ -366,17 +410,24 @@ static int __fpu__restore_sig(void __user *buf, void __user *buf_fx, int size) ret = __copy_from_user(&fpu->state.xsave, buf_fx, state_size); if (!ret && state_size > offsetof(struct xregs_state, header)) - ret = validate_xstate_header(&fpu->state.xsave.header); + ret = validate_user_xstate_header(&fpu->state.xsave.header); } if (ret) goto err_out; - sanitize_restored_xstate(&fpu->state, envp, xfeatures, fx_only); + sanitize_restored_user_xstate(&fpu->state, envp, user_xfeatures, + fx_only); fpregs_lock(); if (unlikely(init_bv)) copy_kernel_to_xregs(&init_fpstate.xsave, init_bv); - ret = copy_kernel_to_xregs_err(&fpu->state.xsave, xfeatures); + + /* + * Restore previously saved supervisor xstates along with + * copied-in user xstates. + */ + ret = copy_kernel_to_xregs_err(&fpu->state.xsave, + user_xfeatures | xfeatures_mask_supervisor()); } else if (use_fxsr()) { ret = __copy_from_user(&fpu->state.fxsave, buf_fx, state_size); @@ -385,11 +436,14 @@ static int __fpu__restore_sig(void __user *buf, void __user *buf_fx, int size) goto err_out; } - sanitize_restored_xstate(&fpu->state, envp, xfeatures, fx_only); + sanitize_restored_user_xstate(&fpu->state, envp, user_xfeatures, + fx_only); fpregs_lock(); if (use_xsave()) { - u64 init_bv = xfeatures_mask & ~XFEATURE_MASK_FPSSE; + u64 init_bv; + + init_bv = xfeatures_mask_user() & ~XFEATURE_MASK_FPSSE; copy_kernel_to_xregs(&init_fpstate.xsave, init_bv); } @@ -410,7 +464,7 @@ static int __fpu__restore_sig(void __user *buf, void __user *buf_fx, int size) err_out: if (ret) - fpu__clear(fpu); + fpu__clear_user_states(fpu); return ret; } @@ -465,7 +519,7 @@ void fpu__init_prepare_fx_sw_frame(void) fx_sw_reserved.magic1 = FP_XSTATE_MAGIC1; fx_sw_reserved.extended_size = size; - fx_sw_reserved.xfeatures = xfeatures_mask; + fx_sw_reserved.xfeatures = xfeatures_mask_user(); fx_sw_reserved.xstate_size = fpu_user_xstate_size; if (IS_ENABLED(CONFIG_IA32_EMULATION) || diff --git a/arch/x86/kernel/fpu/xstate.c b/arch/x86/kernel/fpu/xstate.c index 6a54e83d5589..bda2e5eaca0e 100644 --- a/arch/x86/kernel/fpu/xstate.c +++ b/arch/x86/kernel/fpu/xstate.c @@ -54,13 +54,15 @@ static short xsave_cpuid_features[] __initdata = { }; /* - * Mask of xstate features supported by the CPU and the kernel: + * This represents the full set of bits that should ever be set in a kernel + * XSAVE buffer, both supervisor and user xstates. */ -u64 xfeatures_mask __read_mostly; +u64 xfeatures_mask_all __read_mostly; static unsigned int xstate_offsets[XFEATURE_MAX] = { [ 0 ... XFEATURE_MAX - 1] = -1}; static unsigned int xstate_sizes[XFEATURE_MAX] = { [ 0 ... XFEATURE_MAX - 1] = -1}; static unsigned int xstate_comp_offsets[XFEATURE_MAX] = { [ 0 ... XFEATURE_MAX - 1] = -1}; +static unsigned int xstate_supervisor_only_offsets[XFEATURE_MAX] = { [ 0 ... XFEATURE_MAX - 1] = -1}; /* * The XSAVE area of kernel can be in standard or compacted format; @@ -76,7 +78,7 @@ unsigned int fpu_user_xstate_size; */ int cpu_has_xfeatures(u64 xfeatures_needed, const char **feature_name) { - u64 xfeatures_missing = xfeatures_needed & ~xfeatures_mask; + u64 xfeatures_missing = xfeatures_needed & ~xfeatures_mask_all; if (unlikely(feature_name)) { long xfeature_idx, max_idx; @@ -150,7 +152,7 @@ void fpstate_sanitize_xstate(struct fpu *fpu) * None of the feature bits are in init state. So nothing else * to do for us, as the memory layout is up to date. */ - if ((xfeatures & xfeatures_mask) == xfeatures_mask) + if ((xfeatures & xfeatures_mask_all) == xfeatures_mask_all) return; /* @@ -177,7 +179,7 @@ void fpstate_sanitize_xstate(struct fpu *fpu) * in a special way already: */ feature_bit = 0x2; - xfeatures = (xfeatures_mask & ~xfeatures) >> 2; + xfeatures = (xfeatures_mask_user() & ~xfeatures) >> 2; /* * Update all the remaining memory layouts according to their @@ -205,30 +207,39 @@ void fpstate_sanitize_xstate(struct fpu *fpu) */ void fpu__init_cpu_xstate(void) { - if (!boot_cpu_has(X86_FEATURE_XSAVE) || !xfeatures_mask) + u64 unsup_bits; + + if (!boot_cpu_has(X86_FEATURE_XSAVE) || !xfeatures_mask_all) return; /* - * Make it clear that XSAVES supervisor states are not yet - * implemented should anyone expect it to work by changing - * bits in XFEATURE_MASK_* macros and XCR0. + * Unsupported supervisor xstates should not be found in + * the xfeatures mask. */ - WARN_ONCE((xfeatures_mask & XFEATURE_MASK_SUPERVISOR), - "x86/fpu: XSAVES supervisor states are not yet implemented.\n"); + unsup_bits = xfeatures_mask_all & XFEATURE_MASK_SUPERVISOR_UNSUPPORTED; + WARN_ONCE(unsup_bits, "x86/fpu: Found unsupported supervisor xstates: 0x%llx\n", + unsup_bits); - xfeatures_mask &= ~XFEATURE_MASK_SUPERVISOR; + xfeatures_mask_all &= ~XFEATURE_MASK_SUPERVISOR_UNSUPPORTED; cr4_set_bits(X86_CR4_OSXSAVE); - xsetbv(XCR_XFEATURE_ENABLED_MASK, xfeatures_mask); + + /* + * XCR_XFEATURE_ENABLED_MASK (aka. XCR0) sets user features + * managed by XSAVE{C, OPT, S} and XRSTOR{S}. Only XSAVE user + * states can be set here. + */ + xsetbv(XCR_XFEATURE_ENABLED_MASK, xfeatures_mask_user()); + + /* + * MSR_IA32_XSS sets supervisor states managed by XSAVES. + */ + if (boot_cpu_has(X86_FEATURE_XSAVES)) + wrmsrl(MSR_IA32_XSS, xfeatures_mask_supervisor()); } -/* - * Note that in the future we will likely need a pair of - * functions here: one for user xstates and the other for - * system xstates. For now, they are the same. - */ -static int xfeature_enabled(enum xfeature xfeature) +static bool xfeature_enabled(enum xfeature xfeature) { - return !!(xfeatures_mask & (1UL << xfeature)); + return xfeatures_mask_all & BIT_ULL(xfeature); } /* @@ -383,6 +394,33 @@ static void __init setup_xstate_comp_offsets(void) } /* + * Setup offsets of a supervisor-state-only XSAVES buffer: + * + * The offsets stored in xstate_comp_offsets[] only work for one specific + * value of the Requested Feature BitMap (RFBM). In cases where a different + * RFBM value is used, a different set of offsets is required. This set of + * offsets is for when RFBM=xfeatures_mask_supervisor(). + */ +static void __init setup_supervisor_only_offsets(void) +{ + unsigned int next_offset; + int i; + + next_offset = FXSAVE_SIZE + XSAVE_HDR_SIZE; + + for (i = FIRST_EXTENDED_XFEATURE; i < XFEATURE_MAX; i++) { + if (!xfeature_enabled(i) || !xfeature_is_supervisor(i)) + continue; + + if (xfeature_is_aligned(i)) + next_offset = ALIGN(next_offset, 64); + + xstate_supervisor_only_offsets[i] = next_offset; + next_offset += xstate_sizes[i]; + } +} + +/* * Print out xstate component offsets and sizes */ static void __init print_xstate_offset_size(void) @@ -415,7 +453,7 @@ static void __init setup_init_fpu_buf(void) if (boot_cpu_has(X86_FEATURE_XSAVES)) init_fpstate.xsave.header.xcomp_bv = XCOMP_BV_COMPACTED_FORMAT | - xfeatures_mask; + xfeatures_mask_all; /* * Init all the features state with header.xfeatures being 0x0 @@ -438,7 +476,7 @@ static int xfeature_uncompacted_offset(int xfeature_nr) * format. Checking a supervisor state's uncompacted offset is * an error. */ - if (XFEATURE_MASK_SUPERVISOR & BIT_ULL(xfeature_nr)) { + if (XFEATURE_MASK_SUPERVISOR_ALL & BIT_ULL(xfeature_nr)) { WARN_ONCE(1, "No fixed offset for xstate %d\n", xfeature_nr); return -1; } @@ -472,10 +510,10 @@ int using_compacted_format(void) } /* Validate an xstate header supplied by userspace (ptrace or sigreturn) */ -int validate_xstate_header(const struct xstate_header *hdr) +int validate_user_xstate_header(const struct xstate_header *hdr) { /* No unknown or supervisor features may be set */ - if (hdr->xfeatures & (~xfeatures_mask | XFEATURE_MASK_SUPERVISOR)) + if (hdr->xfeatures & ~xfeatures_mask_user()) return -EINVAL; /* Userspace must use the uncompacted format */ @@ -610,15 +648,12 @@ static void do_extra_xstate_size_checks(void) /* - * Get total size of enabled xstates in XCR0/xfeatures_mask. + * Get total size of enabled xstates in XCR0 | IA32_XSS. * * Note the SDM's wording here. "sub-function 0" only enumerates * the size of the *user* states. If we use it to size a buffer * that we use 'XSAVES' on, we could potentially overflow the * buffer because 'XSAVES' saves system states too. - * - * Note that we do not currently set any bits on IA32_XSS so - * 'XCR0 | IA32_XSS == XCR0' for now. */ static unsigned int __init get_xsaves_size(void) { @@ -700,7 +735,7 @@ static int __init init_xstate_size(void) */ static void fpu__init_disable_system_xstate(void) { - xfeatures_mask = 0; + xfeatures_mask_all = 0; cr4_clear_bits(X86_CR4_OSXSAVE); setup_clear_cpu_cap(X86_FEATURE_XSAVE); } @@ -735,16 +770,26 @@ void __init fpu__init_system_xstate(void) return; } + /* + * Find user xstates supported by the processor. + */ cpuid_count(XSTATE_CPUID, 0, &eax, &ebx, &ecx, &edx); - xfeatures_mask = eax + ((u64)edx << 32); + xfeatures_mask_all = eax + ((u64)edx << 32); - if ((xfeatures_mask & XFEATURE_MASK_FPSSE) != XFEATURE_MASK_FPSSE) { + /* + * Find supervisor xstates supported by the processor. + */ + cpuid_count(XSTATE_CPUID, 1, &eax, &ebx, &ecx, &edx); + xfeatures_mask_all |= ecx + ((u64)edx << 32); + + if ((xfeatures_mask_user() & XFEATURE_MASK_FPSSE) != XFEATURE_MASK_FPSSE) { /* * This indicates that something really unexpected happened * with the enumeration. Disable XSAVE and try to continue * booting without it. This is too early to BUG(). */ - pr_err("x86/fpu: FP/SSE not present amongst the CPU's xstate features: 0x%llx.\n", xfeatures_mask); + pr_err("x86/fpu: FP/SSE not present amongst the CPU's xstate features: 0x%llx.\n", + xfeatures_mask_all); goto out_disable; } @@ -753,10 +798,10 @@ void __init fpu__init_system_xstate(void) */ for (i = 0; i < ARRAY_SIZE(xsave_cpuid_features); i++) { if (!boot_cpu_has(xsave_cpuid_features[i])) - xfeatures_mask &= ~BIT(i); + xfeatures_mask_all &= ~BIT_ULL(i); } - xfeatures_mask &= fpu__get_supported_xfeatures_mask(); + xfeatures_mask_all &= fpu__get_supported_xfeatures_mask(); /* Enable xstate instructions to be able to continue with initialization: */ fpu__init_cpu_xstate(); @@ -768,15 +813,16 @@ void __init fpu__init_system_xstate(void) * Update info used for ptrace frames; use standard-format size and no * supervisor xstates: */ - update_regset_xstate_info(fpu_user_xstate_size, xfeatures_mask & ~XFEATURE_MASK_SUPERVISOR); + update_regset_xstate_info(fpu_user_xstate_size, xfeatures_mask_user()); fpu__init_prepare_fx_sw_frame(); setup_init_fpu_buf(); setup_xstate_comp_offsets(); + setup_supervisor_only_offsets(); print_xstate_offset_size(); pr_info("x86/fpu: Enabled xstate features 0x%llx, context size is %d bytes, using '%s' format.\n", - xfeatures_mask, + xfeatures_mask_all, fpu_kernel_xstate_size, boot_cpu_has(X86_FEATURE_XSAVES) ? "compacted" : "standard"); return; @@ -795,7 +841,14 @@ void fpu__resume_cpu(void) * Restore XCR0 on xsave capable CPUs: */ if (boot_cpu_has(X86_FEATURE_XSAVE)) - xsetbv(XCR_XFEATURE_ENABLED_MASK, xfeatures_mask); + xsetbv(XCR_XFEATURE_ENABLED_MASK, xfeatures_mask_user()); + + /* + * Restore IA32_XSS. The same CPUID bit enumerates support + * of XSAVES and MSR_IA32_XSS. + */ + if (boot_cpu_has(X86_FEATURE_XSAVES)) + wrmsrl(MSR_IA32_XSS, xfeatures_mask_supervisor()); } /* @@ -840,10 +893,9 @@ void *get_xsave_addr(struct xregs_state *xsave, int xfeature_nr) /* * We should not ever be requesting features that we - * have not enabled. Remember that xfeatures_mask is - * what we write to the XCR0 register. + * have not enabled. */ - WARN_ONCE(!(xfeatures_mask & BIT_ULL(xfeature_nr)), + WARN_ONCE(!(xfeatures_mask_all & BIT_ULL(xfeature_nr)), "get of unsupported state"); /* * This assumes the last 'xsave*' instruction to @@ -1010,7 +1062,7 @@ int copy_xstate_to_kernel(void *kbuf, struct xregs_state *xsave, unsigned int of */ memset(&header, 0, sizeof(header)); header.xfeatures = xsave->header.xfeatures; - header.xfeatures &= ~XFEATURE_MASK_SUPERVISOR; + header.xfeatures &= xfeatures_mask_user(); if (header.xfeatures & XFEATURE_MASK_FP) copy_part(0, off_mxcsr, @@ -1090,7 +1142,7 @@ int copy_xstate_to_user(void __user *ubuf, struct xregs_state *xsave, unsigned i */ memset(&header, 0, sizeof(header)); header.xfeatures = xsave->header.xfeatures; - header.xfeatures &= ~XFEATURE_MASK_SUPERVISOR; + header.xfeatures &= xfeatures_mask_user(); /* * Copy xregs_state->header: @@ -1157,7 +1209,7 @@ int copy_kernel_to_xstate(struct xregs_state *xsave, const void *kbuf) memcpy(&hdr, kbuf + offset, size); - if (validate_xstate_header(&hdr)) + if (validate_user_xstate_header(&hdr)) return -EINVAL; for (i = 0; i < XFEATURE_MAX; i++) { @@ -1183,7 +1235,7 @@ int copy_kernel_to_xstate(struct xregs_state *xsave, const void *kbuf) * The state that came in from userspace was user-state only. * Mask all the user states out of 'xfeatures': */ - xsave->header.xfeatures &= XFEATURE_MASK_SUPERVISOR; + xsave->header.xfeatures &= XFEATURE_MASK_SUPERVISOR_ALL; /* * Add back in the features that came in from userspace: @@ -1211,7 +1263,7 @@ int copy_user_to_xstate(struct xregs_state *xsave, const void __user *ubuf) if (__copy_from_user(&hdr, ubuf + offset, size)) return -EFAULT; - if (validate_xstate_header(&hdr)) + if (validate_user_xstate_header(&hdr)) return -EINVAL; for (i = 0; i < XFEATURE_MAX; i++) { @@ -1239,7 +1291,7 @@ int copy_user_to_xstate(struct xregs_state *xsave, const void __user *ubuf) * The state that came in from userspace was user-state only. * Mask all the user states out of 'xfeatures': */ - xsave->header.xfeatures &= XFEATURE_MASK_SUPERVISOR; + xsave->header.xfeatures &= XFEATURE_MASK_SUPERVISOR_ALL; /* * Add back in the features that came in from userspace: @@ -1249,6 +1301,61 @@ int copy_user_to_xstate(struct xregs_state *xsave, const void __user *ubuf) return 0; } +/* + * Save only supervisor states to the kernel buffer. This blows away all + * old states, and is intended to be used only in __fpu__restore_sig(), where + * user states are restored from the user buffer. + */ +void copy_supervisor_to_kernel(struct xregs_state *xstate) +{ + struct xstate_header *header; + u64 max_bit, min_bit; + u32 lmask, hmask; + int err, i; + + if (WARN_ON(!boot_cpu_has(X86_FEATURE_XSAVES))) + return; + + if (!xfeatures_mask_supervisor()) + return; + + max_bit = __fls(xfeatures_mask_supervisor()); + min_bit = __ffs(xfeatures_mask_supervisor()); + + lmask = xfeatures_mask_supervisor(); + hmask = xfeatures_mask_supervisor() >> 32; + XSTATE_OP(XSAVES, xstate, lmask, hmask, err); + + /* We should never fault when copying to a kernel buffer: */ + if (WARN_ON_FPU(err)) + return; + + /* + * At this point, the buffer has only supervisor states and must be + * converted back to normal kernel format. + */ + header = &xstate->header; + header->xcomp_bv |= xfeatures_mask_all; + + /* + * This only moves states up in the buffer. Start with + * the last state and move backwards so that states are + * not overwritten until after they are moved. Note: + * memmove() allows overlapping src/dst buffers. + */ + for (i = max_bit; i >= min_bit; i--) { + u8 *xbuf = (u8 *)xstate; + + if (!((header->xfeatures >> i) & 1)) + continue; + + /* Move xfeature 'i' into its normal location */ + memmove(xbuf + xstate_comp_offsets[i], + xbuf + xstate_supervisor_only_offsets[i], + xstate_sizes[i]); + } +} + #ifdef CONFIG_PROC_PID_ARCH_STATUS /* * Report the amount of time elapsed in millisecond since last AVX512 diff --git a/arch/x86/kernel/ftrace.c b/arch/x86/kernel/ftrace.c index b0e641793be4..c84d28e90a58 100644 --- a/arch/x86/kernel/ftrace.c +++ b/arch/x86/kernel/ftrace.c @@ -282,7 +282,8 @@ static inline void tramp_free(void *tramp) { } /* Defined as markers to the end of the ftrace default trampolines */ extern void ftrace_regs_caller_end(void); -extern void ftrace_epilogue(void); +extern void ftrace_regs_caller_ret(void); +extern void ftrace_caller_end(void); extern void ftrace_caller_op_ptr(void); extern void ftrace_regs_caller_op_ptr(void); @@ -334,7 +335,7 @@ create_trampoline(struct ftrace_ops *ops, unsigned int *tramp_size) call_offset = (unsigned long)ftrace_regs_call; } else { start_offset = (unsigned long)ftrace_caller; - end_offset = (unsigned long)ftrace_epilogue; + end_offset = (unsigned long)ftrace_caller_end; op_offset = (unsigned long)ftrace_caller_op_ptr; call_offset = (unsigned long)ftrace_call; } @@ -366,6 +367,13 @@ create_trampoline(struct ftrace_ops *ops, unsigned int *tramp_size) if (WARN_ON(ret < 0)) goto fail; + if (ops->flags & FTRACE_OPS_FL_SAVE_REGS) { + ip = trampoline + (ftrace_regs_caller_ret - ftrace_regs_caller); + ret = probe_kernel_read(ip, (void *)retq, RET_SIZE); + if (WARN_ON(ret < 0)) + goto fail; + } + /* * The address of the ftrace_ops that is used for this trampoline * is stored at the end of the trampoline. This will be used to @@ -433,7 +441,7 @@ void set_ftrace_ops_ro(void) end_offset = (unsigned long)ftrace_regs_caller_end; } else { start_offset = (unsigned long)ftrace_caller; - end_offset = (unsigned long)ftrace_epilogue; + end_offset = (unsigned long)ftrace_caller_end; } size = end_offset - start_offset; size = size + RET_SIZE + sizeof(void *); diff --git a/arch/x86/kernel/ftrace_32.S b/arch/x86/kernel/ftrace_32.S index e8a9f8370112..e405fe1a8bf4 100644 --- a/arch/x86/kernel/ftrace_32.S +++ b/arch/x86/kernel/ftrace_32.S @@ -189,5 +189,5 @@ return_to_handler: movl %eax, %ecx popl %edx popl %eax - JMP_NOSPEC %ecx + JMP_NOSPEC ecx #endif diff --git a/arch/x86/kernel/ftrace_64.S b/arch/x86/kernel/ftrace_64.S index 369e61faacfe..aa5d28aeb31e 100644 --- a/arch/x86/kernel/ftrace_64.S +++ b/arch/x86/kernel/ftrace_64.S @@ -23,7 +23,7 @@ #endif /* CONFIG_FRAME_POINTER */ /* Size of stack used to save mcount regs in save_mcount_regs */ -#define MCOUNT_REG_SIZE (SS+8 + MCOUNT_FRAME_SIZE) +#define MCOUNT_REG_SIZE (FRAME_SIZE + MCOUNT_FRAME_SIZE) /* * gcc -pg option adds a call to 'mcount' in most functions. @@ -77,7 +77,7 @@ /* * We add enough stack to save all regs. */ - subq $(MCOUNT_REG_SIZE - MCOUNT_FRAME_SIZE), %rsp + subq $(FRAME_SIZE), %rsp movq %rax, RAX(%rsp) movq %rcx, RCX(%rsp) movq %rdx, RDX(%rsp) @@ -157,8 +157,12 @@ SYM_INNER_LABEL(ftrace_call, SYM_L_GLOBAL) * think twice before adding any new code or changing the * layout here. */ -SYM_INNER_LABEL(ftrace_epilogue, SYM_L_GLOBAL) +SYM_INNER_LABEL(ftrace_caller_end, SYM_L_GLOBAL) + jmp ftrace_epilogue +SYM_FUNC_END(ftrace_caller); + +SYM_FUNC_START(ftrace_epilogue) #ifdef CONFIG_FUNCTION_GRAPH_TRACER SYM_INNER_LABEL(ftrace_graph_call, SYM_L_GLOBAL) jmp ftrace_stub @@ -170,14 +174,12 @@ SYM_INNER_LABEL(ftrace_graph_call, SYM_L_GLOBAL) */ SYM_INNER_LABEL_ALIGN(ftrace_stub, SYM_L_WEAK) retq -SYM_FUNC_END(ftrace_caller) +SYM_FUNC_END(ftrace_epilogue) SYM_FUNC_START(ftrace_regs_caller) /* Save the current flags before any operations that can change them */ pushfq - UNWIND_HINT_SAVE - /* added 8 bytes to save flags */ save_mcount_regs 8 /* save_mcount_regs fills in first two parameters */ @@ -233,10 +235,13 @@ SYM_INNER_LABEL(ftrace_regs_call, SYM_L_GLOBAL) movq ORIG_RAX(%rsp), %rax movq %rax, MCOUNT_REG_SIZE-8(%rsp) - /* If ORIG_RAX is anything but zero, make this a call to that */ + /* + * If ORIG_RAX is anything but zero, make this a call to that. + * See arch_ftrace_set_direct_caller(). + */ movq ORIG_RAX(%rsp), %rax - cmpq $0, %rax - je 1f + testq %rax, %rax + jz 1f /* Swap the flags with orig_rax */ movq MCOUNT_REG_SIZE(%rsp), %rdi @@ -244,20 +249,14 @@ SYM_INNER_LABEL(ftrace_regs_call, SYM_L_GLOBAL) movq %rax, MCOUNT_REG_SIZE(%rsp) restore_mcount_regs 8 + /* Restore flags */ + popfq - jmp 2f +SYM_INNER_LABEL(ftrace_regs_caller_ret, SYM_L_GLOBAL); + UNWIND_HINT_RET_OFFSET + jmp ftrace_epilogue 1: restore_mcount_regs - - -2: - /* - * The stack layout is nondetermistic here, depending on which path was - * taken. This confuses objtool and ORC, rightfully so. For now, - * pretend the stack always looks like the non-direct case. - */ - UNWIND_HINT_RESTORE - /* Restore flags */ popfq @@ -268,7 +267,6 @@ SYM_INNER_LABEL(ftrace_regs_call, SYM_L_GLOBAL) * to the return. */ SYM_INNER_LABEL(ftrace_regs_caller_end, SYM_L_GLOBAL) - jmp ftrace_epilogue SYM_FUNC_END(ftrace_regs_caller) @@ -303,7 +301,7 @@ trace: * function tracing is enabled. */ movq ftrace_trace_function, %r8 - CALL_NOSPEC %r8 + CALL_NOSPEC r8 restore_mcount_regs jmp fgraph_trace @@ -340,6 +338,6 @@ SYM_CODE_START(return_to_handler) movq 8(%rsp), %rdx movq (%rsp), %rax addq $24, %rsp - JMP_NOSPEC %rdi + JMP_NOSPEC rdi SYM_CODE_END(return_to_handler) #endif diff --git a/arch/x86/kernel/nmi.c b/arch/x86/kernel/nmi.c index 6407ea21fa1b..bdcc5146de96 100644 --- a/arch/x86/kernel/nmi.c +++ b/arch/x86/kernel/nmi.c @@ -25,10 +25,6 @@ #include <linux/atomic.h> #include <linux/sched/clock.h> -#if defined(CONFIG_EDAC) -#include <linux/edac.h> -#endif - #include <asm/cpu_entry_area.h> #include <asm/traps.h> #include <asm/mach_traps.h> diff --git a/arch/x86/kernel/process.c b/arch/x86/kernel/process.c index 35638f1c5791..ce6cd220f722 100644 --- a/arch/x86/kernel/process.c +++ b/arch/x86/kernel/process.c @@ -191,7 +191,7 @@ void flush_thread(void) flush_ptrace_hw_breakpoint(tsk); memset(tsk->thread.tls_array, 0, sizeof(tsk->thread.tls_array)); - fpu__clear(&tsk->thread.fpu); + fpu__clear_all(&tsk->thread.fpu); } void disable_TSC(void) diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c index 4b3fa6cd3106..a3767e74c758 100644 --- a/arch/x86/kernel/setup.c +++ b/arch/x86/kernel/setup.c @@ -237,6 +237,9 @@ static u64 __init get_ramdisk_image(void) ramdisk_image |= (u64)boot_params.ext_ramdisk_image << 32; + if (ramdisk_image == 0) + ramdisk_image = phys_initrd_start; + return ramdisk_image; } static u64 __init get_ramdisk_size(void) @@ -245,6 +248,9 @@ static u64 __init get_ramdisk_size(void) ramdisk_size |= (u64)boot_params.ext_ramdisk_size << 32; + if (ramdisk_size == 0) + ramdisk_size = phys_initrd_size; + return ramdisk_size; } diff --git a/arch/x86/kernel/signal.c b/arch/x86/kernel/signal.c index 83b74fb38c8f..399f97abee02 100644 --- a/arch/x86/kernel/signal.c +++ b/arch/x86/kernel/signal.c @@ -37,6 +37,7 @@ #include <asm/vm86.h> #ifdef CONFIG_X86_64 +#include <linux/compat.h> #include <asm/proto.h> #include <asm/ia32_unistd.h> #endif /* CONFIG_X86_64 */ @@ -511,6 +512,31 @@ Efault: } #endif /* CONFIG_X86_32 */ +#ifdef CONFIG_X86_X32_ABI +static int x32_copy_siginfo_to_user(struct compat_siginfo __user *to, + const struct kernel_siginfo *from) +{ + struct compat_siginfo new; + + copy_siginfo_to_external32(&new, from); + if (from->si_signo == SIGCHLD) { + new._sifields._sigchld_x32._utime = from->si_utime; + new._sifields._sigchld_x32._stime = from->si_stime; + } + if (copy_to_user(to, &new, sizeof(struct compat_siginfo))) + return -EFAULT; + return 0; +} + +int copy_siginfo_to_user32(struct compat_siginfo __user *to, + const struct kernel_siginfo *from) +{ + if (in_x32_syscall()) + return x32_copy_siginfo_to_user(to, from); + return __copy_siginfo_to_user32(to, from); +} +#endif /* CONFIG_X86_X32_ABI */ + static int x32_setup_rt_frame(struct ksignal *ksig, compat_sigset_t *set, struct pt_regs *regs) @@ -543,7 +569,7 @@ static int x32_setup_rt_frame(struct ksignal *ksig, user_access_end(); if (ksig->ka.sa.sa_flags & SA_SIGINFO) { - if (__copy_siginfo_to_user32(&frame->info, &ksig->info, true)) + if (x32_copy_siginfo_to_user(&frame->info, &ksig->info)) return -EFAULT; } @@ -732,7 +758,7 @@ handle_signal(struct ksignal *ksig, struct pt_regs *regs) /* * Ensure the signal handler starts with the new fpu state. */ - fpu__clear(fpu); + fpu__clear_user_states(fpu); } signal_setup_done(failed, ksig, stepping); } diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c index 2f24c334a938..2467f3dd35d3 100644 --- a/arch/x86/kernel/smpboot.c +++ b/arch/x86/kernel/smpboot.c @@ -1384,12 +1384,12 @@ void __init native_smp_prepare_cpus(unsigned int max_cpus) speculative_store_bypass_ht_init(); } -void arch_enable_nonboot_cpus_begin(void) +void arch_thaw_secondary_cpus_begin(void) { set_mtrr_aps_delayed_init(); } -void arch_enable_nonboot_cpus_end(void) +void arch_thaw_secondary_cpus_end(void) { mtrr_aps_init(); } @@ -1857,24 +1857,25 @@ static bool slv_set_max_freq_ratio(u64 *base_freq, u64 *turbo_freq) #include <asm/cpu_device_id.h> #include <asm/intel-family.h> -#define ICPU(model) \ - {X86_VENDOR_INTEL, 6, model, X86_FEATURE_APERFMPERF, 0} +#define X86_MATCH(model) \ + X86_MATCH_VENDOR_FAM_MODEL_FEATURE(INTEL, 6, \ + INTEL_FAM6_##model, X86_FEATURE_APERFMPERF, NULL) static const struct x86_cpu_id has_knl_turbo_ratio_limits[] = { - ICPU(INTEL_FAM6_XEON_PHI_KNL), - ICPU(INTEL_FAM6_XEON_PHI_KNM), + X86_MATCH(XEON_PHI_KNL), + X86_MATCH(XEON_PHI_KNM), {} }; static const struct x86_cpu_id has_skx_turbo_ratio_limits[] = { - ICPU(INTEL_FAM6_SKYLAKE_X), + X86_MATCH(SKYLAKE_X), {} }; static const struct x86_cpu_id has_glm_turbo_ratio_limits[] = { - ICPU(INTEL_FAM6_ATOM_GOLDMONT), - ICPU(INTEL_FAM6_ATOM_GOLDMONT_D), - ICPU(INTEL_FAM6_ATOM_GOLDMONT_PLUS), + X86_MATCH(ATOM_GOLDMONT), + X86_MATCH(ATOM_GOLDMONT_D), + X86_MATCH(ATOM_GOLDMONT_PLUS), {} }; diff --git a/arch/x86/kernel/tboot.c b/arch/x86/kernel/tboot.c index b89f6ac6a0c0..b2942b2dbfcf 100644 --- a/arch/x86/kernel/tboot.c +++ b/arch/x86/kernel/tboot.c @@ -35,8 +35,7 @@ #include "../realmode/rm/wakeup.h" /* Global pointer to shared data; NULL means no measured launch. */ -struct tboot *tboot __read_mostly; -EXPORT_SYMBOL(tboot); +static struct tboot *tboot __read_mostly; /* timeout for APs (in secs) to enter wait-for-SIPI state during shutdown */ #define AP_WAIT_TIMEOUT 1 @@ -46,6 +45,11 @@ EXPORT_SYMBOL(tboot); static u8 tboot_uuid[16] __initdata = TBOOT_UUID; +bool tboot_enabled(void) +{ + return tboot != NULL; +} + void __init tboot_probe(void) { /* Look for valid page-aligned address for shared page. */ diff --git a/arch/x86/kernel/traps.c b/arch/x86/kernel/traps.c index d54cffdc7cac..428186d9de46 100644 --- a/arch/x86/kernel/traps.c +++ b/arch/x86/kernel/traps.c @@ -37,10 +37,12 @@ #include <linux/mm.h> #include <linux/smp.h> #include <linux/io.h> +#include <linux/hardirq.h> +#include <linux/atomic.h> + #include <asm/stacktrace.h> #include <asm/processor.h> #include <asm/debugreg.h> -#include <linux/atomic.h> #include <asm/text-patching.h> #include <asm/ftrace.h> #include <asm/traps.h> @@ -82,78 +84,6 @@ static inline void cond_local_irq_disable(struct pt_regs *regs) local_irq_disable(); } -/* - * In IST context, we explicitly disable preemption. This serves two - * purposes: it makes it much less likely that we would accidentally - * schedule in IST context and it will force a warning if we somehow - * manage to schedule by accident. - */ -void ist_enter(struct pt_regs *regs) -{ - if (user_mode(regs)) { - RCU_LOCKDEP_WARN(!rcu_is_watching(), "entry code didn't wake RCU"); - } else { - /* - * We might have interrupted pretty much anything. In - * fact, if we're a machine check, we can even interrupt - * NMI processing. We don't want in_nmi() to return true, - * but we need to notify RCU. - */ - rcu_nmi_enter(); - } - - preempt_disable(); - - /* This code is a bit fragile. Test it. */ - RCU_LOCKDEP_WARN(!rcu_is_watching(), "ist_enter didn't work"); -} -NOKPROBE_SYMBOL(ist_enter); - -void ist_exit(struct pt_regs *regs) -{ - preempt_enable_no_resched(); - - if (!user_mode(regs)) - rcu_nmi_exit(); -} - -/** - * ist_begin_non_atomic() - begin a non-atomic section in an IST exception - * @regs: regs passed to the IST exception handler - * - * IST exception handlers normally cannot schedule. As a special - * exception, if the exception interrupted userspace code (i.e. - * user_mode(regs) would return true) and the exception was not - * a double fault, it can be safe to schedule. ist_begin_non_atomic() - * begins a non-atomic section within an ist_enter()/ist_exit() region. - * Callers are responsible for enabling interrupts themselves inside - * the non-atomic section, and callers must call ist_end_non_atomic() - * before ist_exit(). - */ -void ist_begin_non_atomic(struct pt_regs *regs) -{ - BUG_ON(!user_mode(regs)); - - /* - * Sanity check: we need to be on the normal thread stack. This - * will catch asm bugs and any attempt to use ist_preempt_enable - * from double_fault. - */ - BUG_ON(!on_thread_stack()); - - preempt_enable_no_resched(); -} - -/** - * ist_end_non_atomic() - begin a non-atomic section in an IST exception - * - * Ends a non-atomic section started with ist_begin_non_atomic(). - */ -void ist_end_non_atomic(void) -{ - preempt_disable(); -} - int is_valid_bugaddr(unsigned long addr) { unsigned short ud; @@ -326,7 +256,6 @@ __visible void __noreturn handle_stack_overflow(const char *message, } #endif -#if defined(CONFIG_X86_64) || defined(CONFIG_DOUBLEFAULT) /* * Runs on an IST stack for x86_64 and on a special task stack for x86_32. * @@ -363,7 +292,7 @@ dotraplinkage void do_double_fault(struct pt_regs *regs, long error_code, unsign * The net result is that our #GP handler will think that we * entered from usermode with the bad user context. * - * No need for ist_enter here because we don't use RCU. + * No need for nmi_enter() here because we don't use RCU. */ if (((long)regs->sp >> P4D_SHIFT) == ESPFIX_PGD_ENTRY && regs->cs == __KERNEL_CS && @@ -398,7 +327,7 @@ dotraplinkage void do_double_fault(struct pt_regs *regs, long error_code, unsign } #endif - ist_enter(regs); + nmi_enter(); notify_die(DIE_TRAP, str, regs, error_code, X86_TRAP_DF, SIGSEGV); tsk->thread.error_code = error_code; @@ -450,7 +379,6 @@ dotraplinkage void do_double_fault(struct pt_regs *regs, long error_code, unsign die("double fault", regs, error_code); panic("Machine halted."); } -#endif dotraplinkage void do_bounds(struct pt_regs *regs, long error_code) { @@ -592,19 +520,13 @@ dotraplinkage void notrace do_int3(struct pt_regs *regs, long error_code) return; /* - * Unlike any other non-IST entry, we can be called from a kprobe in - * non-CONTEXT_KERNEL kernel mode or even during context tracking - * state changes. Make sure that we wake up RCU even if we're coming - * from kernel code. - * - * This means that we can't schedule even if we came from a - * preemptible kernel context. That's okay. + * Unlike any other non-IST entry, we can be called from pretty much + * any location in the kernel through kprobes -- text_poke() will most + * likely be handled by poke_int3_handler() above. This means this + * handler is effectively NMI-like. */ - if (!user_mode(regs)) { - rcu_nmi_enter(); - preempt_disable(); - } - RCU_LOCKDEP_WARN(!rcu_is_watching(), "entry code didn't wake RCU"); + if (!user_mode(regs)) + nmi_enter(); #ifdef CONFIG_KGDB_LOW_LEVEL_TRAP if (kgdb_ll_trap(DIE_INT3, "int3", regs, error_code, X86_TRAP_BP, @@ -626,10 +548,8 @@ dotraplinkage void notrace do_int3(struct pt_regs *regs, long error_code) cond_local_irq_disable(regs); exit: - if (!user_mode(regs)) { - preempt_enable_no_resched(); - rcu_nmi_exit(); - } + if (!user_mode(regs)) + nmi_exit(); } NOKPROBE_SYMBOL(do_int3); @@ -733,7 +653,7 @@ dotraplinkage void do_debug(struct pt_regs *regs, long error_code) unsigned long dr6; int si_code; - ist_enter(regs); + nmi_enter(); get_debugreg(dr6, 6); /* @@ -826,7 +746,7 @@ dotraplinkage void do_debug(struct pt_regs *regs, long error_code) debug_stack_usage_dec(); exit: - ist_exit(regs); + nmi_exit(); } NOKPROBE_SYMBOL(do_debug); |