Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel...

Pull x86 fixes from Ingo Molnar:
 - misc fixes all around the map
 - block non-root vm86(old) if mmap_min_addr != 0
 - two small debuggability improvements
 - removal of obsolete paravirt op

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/platform: Fix Geode LX timekeeping in the generic x86 build
  x86/apic: Serialize LVTT and TSC_DEADLINE writes
  x86/ioapic: Force affinity setting in setup_ioapic_dest()
  x86/paravirt: Remove the unused pv_time_ops::get_tsc_khz method
  x86/ldt: Fix small LDT allocation for Xen
  x86/vm86: Fix the misleading CONFIG_VM86 Kconfig help text
  x86/cpu: Print family/model/stepping in hex
  x86/vm86: Block non-root vm86(old) if mmap_min_addr != 0
  x86/alternatives: Make optimize_nops() interrupt safe and synced
  x86/mm/srat: Print non-volatile flag in SRAT
  x86/cpufeatures: Enable cpuid for Intel SHA extensions

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 7aef2d5..328c835 100644 (file)
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -1006,7 +1006,7 @@ config X86_THERMAL_VECTOR
        depends on X86_MCE_INTEL
 
 config X86_LEGACY_VM86
-       bool "Legacy VM86 support (obsolete)"
+       bool "Legacy VM86 support"
        default n
        depends on X86_32
        ---help---
@@ -1018,19 +1018,20 @@ config X86_LEGACY_VM86
          available to accelerate real mode DOS programs.  However, any
          recent version of DOSEMU, X, or vbetool should be fully
          functional even without kernel VM86 support, as they will all
-         fall back to (pretty well performing) software emulation.
+         fall back to software emulation. Nevertheless, if you are using
+         a 16-bit DOS program where 16-bit performance matters, vm86
+         mode might be faster than emulation and you might want to
+         enable this option.
 
-         Anything that works on a 64-bit kernel is unlikely to need
-         this option, as 64-bit kernels don't, and can't, support V8086
-         mode.  This option is also unrelated to 16-bit protected mode
-         and is not needed to run most 16-bit programs under Wine.
+         Note that any app that works on a 64-bit kernel is unlikely to
+         need this option, as 64-bit kernels don't, and can't, support
+         V8086 mode. This option is also unrelated to 16-bit protected
+         mode and is not needed to run most 16-bit programs under Wine.
 
-         Enabling this option adds considerable attack surface to the
-         kernel and slows down system calls and exception handling.
+         Enabling this option increases the complexity of the kernel
+         and slows down exception handling a tiny bit.
 
-         Unless you use very old userspace or need the last drop of
-         performance in your real mode DOS games and can't use KVM,
-         say N here.
+         If unsure, say N here.
 
 config VM86
        bool

diff --git a/arch/x86/include/asm/cpufeature.h b/arch/x86/include/asm/cpufeature.h
index 477fc28..e6cf2ad 100644 (file)
--- a/arch/x86/include/asm/cpufeature.h
+++ b/arch/x86/include/asm/cpufeature.h
@@ -241,6 +241,7 @@
 #define X86_FEATURE_AVX512PF   ( 9*32+26) /* AVX-512 Prefetch */
 #define X86_FEATURE_AVX512ER   ( 9*32+27) /* AVX-512 Exponential and Reciprocal */
 #define X86_FEATURE_AVX512CD   ( 9*32+28) /* AVX-512 Conflict Detection */
+#define X86_FEATURE_SHA_NI     ( 9*32+29) /* SHA1/SHA256 Instruction Extensions */
 
 /* Extended state features, CPUID level 0x0000000d:1 (eax), word 10 */
 #define X86_FEATURE_XSAVEOPT   (10*32+ 0) /* XSAVEOPT */

diff --git a/arch/x86/include/asm/paravirt_types.h b/arch/x86/include/asm/paravirt_types.h
index ce029e4..31247b5 100644 (file)
--- a/arch/x86/include/asm/paravirt_types.h
+++ b/arch/x86/include/asm/paravirt_types.h
@@ -97,7 +97,6 @@ struct pv_lazy_ops {
 struct pv_time_ops {
        unsigned long long (*sched_clock)(void);
        unsigned long long (*steal_clock)(int cpu);
-       unsigned long (*get_tsc_khz)(void);
 };
 
 struct pv_cpu_ops {

diff --git a/arch/x86/kernel/alternative.c b/arch/x86/kernel/alternative.c
index c42827e..25f9093 100644 (file)
--- a/arch/x86/kernel/alternative.c
+++ b/arch/x86/kernel/alternative.c
@@ -338,10 +338,15 @@ done:
 
 static void __init_or_module optimize_nops(struct alt_instr *a, u8 *instr)
 {
+       unsigned long flags;
+
        if (instr[0] != 0x90)
                return;
 
+       local_irq_save(flags);
        add_nops(instr + (a->instrlen - a->padlen), a->padlen);
+       sync_core();
+       local_irq_restore(flags);
 
        DUMP_BYTES(instr, a->instrlen, "%p: [%d:%d) optimized NOPs: ",
                   instr, a->instrlen - a->padlen, a->padlen);

diff --git a/arch/x86/kernel/apic/apic.c b/arch/x86/kernel/apic/apic.c
index 3ca3e46..24e94ce 100644 (file)
--- a/arch/x86/kernel/apic/apic.c
+++ b/arch/x86/kernel/apic/apic.c
@@ -336,6 +336,13 @@ static void __setup_APIC_LVTT(unsigned int clocks, int oneshot, int irqen)
        apic_write(APIC_LVTT, lvtt_value);
 
        if (lvtt_value & APIC_LVT_TIMER_TSCDEADLINE) {
+               /*
+                * See Intel SDM: TSC-Deadline Mode chapter. In xAPIC mode,
+                * writing to the APIC LVTT and TSC_DEADLINE MSR isn't serialized.
+                * According to Intel, MFENCE can do the serialization here.
+                */
+               asm volatile("mfence" : : : "memory");
+
                printk_once(KERN_DEBUG "TSC deadline timer enabled\n");
                return;
        }

diff --git a/arch/x86/kernel/apic/io_apic.c b/arch/x86/kernel/apic/io_apic.c
index 38a76f8..5c60bb1 100644 (file)
--- a/arch/x86/kernel/apic/io_apic.c
+++ b/arch/x86/kernel/apic/io_apic.c
@@ -2522,6 +2522,7 @@ void __init setup_ioapic_dest(void)
        int pin, ioapic, irq, irq_entry;
        const struct cpumask *mask;
        struct irq_data *idata;
+       struct irq_chip *chip;
 
        if (skip_ioapic_setup == 1)
                return;
@@ -2545,9 +2546,9 @@ void __init setup_ioapic_dest(void)
                else
                        mask = apic->target_cpus();
 
-               irq_set_affinity(irq, mask);
+               chip = irq_data_get_irq_chip(idata);
+               chip->irq_set_affinity(idata, mask, false);
        }
-
 }
 #endif
 

diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
index 07ce52c..de22ea7 100644 (file)
--- a/arch/x86/kernel/cpu/common.c
+++ b/arch/x86/kernel/cpu/common.c
@@ -1110,10 +1110,10 @@ void print_cpu_info(struct cpuinfo_x86 *c)
        else
                printk(KERN_CONT "%d86", c->x86);
 
-       printk(KERN_CONT " (fam: %02x, model: %02x", c->x86, c->x86_model);
+       printk(KERN_CONT " (family: 0x%x, model: 0x%x", c->x86, c->x86_model);
 
        if (c->x86_mask || c->cpuid_level >= 0)
-               printk(KERN_CONT ", stepping: %02x)\n", c->x86_mask);
+               printk(KERN_CONT ", stepping: 0x%x)\n", c->x86_mask);
        else
                printk(KERN_CONT ")\n");
 

diff --git a/arch/x86/kernel/ldt.c b/arch/x86/kernel/ldt.c
index 2bcc052..6acc9dd 100644 (file)
--- a/arch/x86/kernel/ldt.c
+++ b/arch/x86/kernel/ldt.c
@@ -58,7 +58,7 @@ static struct ldt_struct *alloc_ldt_struct(int size)
        if (alloc_size > PAGE_SIZE)
                new_ldt->entries = vzalloc(alloc_size);
        else
-               new_ldt->entries = kzalloc(PAGE_SIZE, GFP_KERNEL);
+               new_ldt->entries = (void *)get_zeroed_page(GFP_KERNEL);
 
        if (!new_ldt->entries) {
                kfree(new_ldt);
@@ -95,7 +95,7 @@ static void free_ldt_struct(struct ldt_struct *ldt)
        if (ldt->size * LDT_ENTRY_SIZE > PAGE_SIZE)
                vfree(ldt->entries);
        else
-               kfree(ldt->entries);
+               free_page((unsigned long)ldt->entries);
        kfree(ldt);
 }
 

diff --git a/arch/x86/kernel/tsc.c b/arch/x86/kernel/tsc.c
index c8d52cb..c3f7602 100644 (file)
--- a/arch/x86/kernel/tsc.c
+++ b/arch/x86/kernel/tsc.c
@@ -21,6 +21,7 @@
 #include <asm/hypervisor.h>
 #include <asm/nmi.h>
 #include <asm/x86_init.h>
+#include <asm/geode.h>
 
 unsigned int __read_mostly cpu_khz;    /* TSC clocks / usec, not used here */
 EXPORT_SYMBOL(cpu_khz);
@@ -1013,15 +1014,17 @@ EXPORT_SYMBOL_GPL(mark_tsc_unstable);
 
 static void __init check_system_tsc_reliable(void)
 {
-#ifdef CONFIG_MGEODE_LX
-       /* RTSC counts during suspend */
+#if defined(CONFIG_MGEODEGX1) || defined(CONFIG_MGEODE_LX) || defined(CONFIG_X86_GENERIC)
+       if (is_geode_lx()) {
+               /* RTSC counts during suspend */
 #define RTSC_SUSP 0x100
-       unsigned long res_low, res_high;
+               unsigned long res_low, res_high;
 
-       rdmsr_safe(MSR_GEODE_BUSCONT_CONF0, &res_low, &res_high);
-       /* Geode_LX - the OLPC CPU has a very reliable TSC */
-       if (res_low & RTSC_SUSP)
-               tsc_clocksource_reliable = 1;
+               rdmsr_safe(MSR_GEODE_BUSCONT_CONF0, &res_low, &res_high);
+               /* Geode_LX - the OLPC CPU has a very reliable TSC */
+               if (res_low & RTSC_SUSP)
+                       tsc_clocksource_reliable = 1;
+       }
 #endif
        if (boot_cpu_has(X86_FEATURE_TSC_RELIABLE))
                tsc_clocksource_reliable = 1;

diff --git a/arch/x86/kernel/vm86_32.c b/arch/x86/kernel/vm86_32.c
index abd8b85..5246193 100644 (file)
--- a/arch/x86/kernel/vm86_32.c
+++ b/arch/x86/kernel/vm86_32.c
@@ -45,6 +45,7 @@
 #include <linux/audit.h>
 #include <linux/stddef.h>
 #include <linux/slab.h>
+#include <linux/security.h>
 
 #include <asm/uaccess.h>
 #include <asm/io.h>
@@ -232,6 +233,32 @@ static long do_sys_vm86(struct vm86plus_struct __user *user_vm86, bool plus)
        struct pt_regs *regs = current_pt_regs();
        unsigned long err = 0;
 
+       err = security_mmap_addr(0);
+       if (err) {
+               /*
+                * vm86 cannot virtualize the address space, so vm86 users
+                * need to manage the low 1MB themselves using mmap.  Given
+                * that BIOS places important data in the first page, vm86
+                * is essentially useless if mmap_min_addr != 0.  DOSEMU,
+                * for example, won't even bother trying to use vm86 if it
+                * can't map a page at virtual address 0.
+                *
+                * To reduce the available kernel attack surface, simply
+                * disallow vm86(old) for users who cannot mmap at va 0.
+                *
+                * The implementation of security_mmap_addr will allow
+                * suitably privileged users to map va 0 even if
+                * vm.mmap_min_addr is set above 0, and we want this
+                * behavior for vm86 as well, as it ensures that legacy
+                * tools like vbetool will not fail just because of
+                * vm.mmap_min_addr.
+                */
+               pr_info_once("Denied a call to vm86(old) from %s[%d] (uid: %d).  Set the vm.mmap_min_addr sysctl to 0 and/or adjust LSM mmap_min_addr policy to enable vm86 if you are using a vm86-based DOS emulator.\n",
+                            current->comm, task_pid_nr(current),
+                            from_kuid_munged(&init_user_ns, current_uid()));
+               return -EPERM;
+       }
+
        if (!vm86) {
                if (!(vm86 = kzalloc(sizeof(*vm86), GFP_KERNEL)))
                        return -ENOMEM;

diff --git a/arch/x86/mm/srat.c b/arch/x86/mm/srat.c
index 66338a6..c2aea63 100644 (file)
--- a/arch/x86/mm/srat.c
+++ b/arch/x86/mm/srat.c
@@ -192,10 +192,11 @@ acpi_numa_memory_affinity_init(struct acpi_srat_mem_affinity *ma)
 
        node_set(node, numa_nodes_parsed);
 
-       pr_info("SRAT: Node %u PXM %u [mem %#010Lx-%#010Lx]%s\n",
+       pr_info("SRAT: Node %u PXM %u [mem %#010Lx-%#010Lx]%s%s\n",
                node, pxm,
                (unsigned long long) start, (unsigned long long) end - 1,
-               hotpluggable ? " hotplug" : "");
+               hotpluggable ? " hotplug" : "",
+               ma->flags & ACPI_SRAT_MEM_NON_VOLATILE ? " non-volatile" : "");
 
        /* Mark hotplug range in memblock. */
        if (hotpluggable && memblock_mark_hotplug(start, ma->length))

diff --git a/tools/testing/selftests/x86/entry_from_vm86.c b/tools/testing/selftests/x86/entry_from_vm86.c
index 9a43a59..421c607 100644 (file)
--- a/tools/testing/selftests/x86/entry_from_vm86.c
+++ b/tools/testing/selftests/x86/entry_from_vm86.c
@@ -116,8 +116,9 @@ static bool do_test(struct vm86plus_struct *v86, unsigned long eip,
        v86->regs.eip = eip;
        ret = vm86(VM86_ENTER, v86);
 
-       if (ret == -1 && errno == ENOSYS) {
-               printf("[SKIP]\tvm86 not supported\n");
+       if (ret == -1 && (errno == ENOSYS || errno == EPERM)) {
+               printf("[SKIP]\tvm86 %s\n",
+                      errno == ENOSYS ? "not supported" : "not allowed");
                return false;
        }