Merge branch 'linus' into x86/core

4 files changed, 198 insertions, 156 deletions

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 0a80d6a5e9f1..21ef9dd36187 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -577,35 +577,29 @@ config SWIOTLB
 
 config IOMMU_HELPER
         def_bool (CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU)
+
 config MAXSMP
         bool "Configure Maximum number of SMP Processors and NUMA Nodes"
-        depends on X86_64 && SMP
+        depends on X86_64 && SMP && BROKEN
         default n
         help
           Configure maximum number of CPUS and NUMA Nodes for this architecture.
           If unsure, say N.
 
-if MAXSMP
-config NR_CPUS
-        int
-        default "4096"
-endif
-
-if !MAXSMP
 config NR_CPUS
-        int "Maximum number of CPUs (2-4096)"
-        range 2 4096
+        int "Maximum number of CPUs (2-512)" if !MAXSMP
+        range 2 512
         depends on SMP
+        default "4096" if MAXSMP
         default "32" if X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000
         default "8"
         help
           This allows you to specify the maximum number of CPUs which this
-          kernel will support.  The maximum supported value is 4096 and the
+          kernel will support.  The maximum supported value is 512 and the
           minimum value which makes sense is 2.
 
           This is purely to save memory - each supported CPU adds
           approximately eight kilobytes to the kernel image.
-endif
 
 config SCHED_SMT
         bool "SMT (Hyperthreading) scheduler support"
@@ -996,17 +990,10 @@ config NUMA_EMU
           into virtual nodes when booted with "numa=fake=N", where N is the
           number of nodes. This is only useful for debugging.
 
-if MAXSMP
-
 config NODES_SHIFT
-        int
-        default "9"
-endif
-
-if !MAXSMP
-config NODES_SHIFT
-        int "Maximum NUMA Nodes (as a power of 2)"
+        int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
         range 1 9   if X86_64
+        default "9" if MAXSMP
         default "6" if X86_64
         default "4" if X86_NUMAQ
         default "3"
@@ -1014,7 +1001,6 @@ config NODES_SHIFT
         help
           Specify the maximum number of NUMA Nodes available on the target
           system.  Increases memory reserved to accomodate various tables.
-endif
 
 config HAVE_ARCH_BOOTMEM_NODE
         def_bool y
diff --git a/arch/x86/kernel/tsc.c b/arch/x86/kernel/tsc.c
index 8e786b0d665a..346cae5ac423 100644
--- a/arch/x86/kernel/tsc.c
+++ b/arch/x86/kernel/tsc.c
@@ -122,80 +122,217 @@ static u64 tsc_read_refs(u64 *pm, u64 *hpet)
         return ULLONG_MAX;
 }
 
-/**
- * native_calibrate_tsc - calibrate the tsc on boot
+/*
+ * Try to calibrate the TSC against the Programmable
+ * Interrupt Timer and return the frequency of the TSC
+ * in kHz.
+ *
+ * Return ULONG_MAX on failure to calibrate.
  */
-unsigned long native_calibrate_tsc(void)
+static unsigned long pit_calibrate_tsc(void)
 {
-        unsigned long flags;
-        u64 tsc1, tsc2, tr1, tr2, delta, pm1, pm2, hpet1, hpet2;
-        int hpet = is_hpet_enabled();
-        unsigned int tsc_khz_val = 0;
-
-        local_irq_save(flags);
-
-        tsc1 = tsc_read_refs(&pm1, hpet ? &hpet1 : NULL);
+        u64 tsc, t1, t2, delta;
+        unsigned long tscmin, tscmax;
+        int pitcnt;
 
+        /* Set the Gate high, disable speaker */
         outb((inb(0x61) & ~0x02) | 0x01, 0x61);
 
+        /*
+         * Setup CTC channel 2* for mode 0, (interrupt on terminal
+         * count mode), binary count. Set the latch register to 50ms
+         * (LSB then MSB) to begin countdown.
+         */
         outb(0xb0, 0x43);
         outb((CLOCK_TICK_RATE / (1000 / 50)) & 0xff, 0x42);
         outb((CLOCK_TICK_RATE / (1000 / 50)) >> 8, 0x42);
-        tr1 = get_cycles();
-        while ((inb(0x61) & 0x20) == 0);
-        tr2 = get_cycles();
 
-        tsc2 = tsc_read_refs(&pm2, hpet ? &hpet2 : NULL);
+        tsc = t1 = t2 = get_cycles();
 
-        local_irq_restore(flags);
+        pitcnt = 0;
+        tscmax = 0;
+        tscmin = ULONG_MAX;
+        while ((inb(0x61) & 0x20) == 0) {
+                t2 = get_cycles();
+                delta = t2 - tsc;
+                tsc = t2;
+                if ((unsigned long) delta < tscmin)
+                        tscmin = (unsigned int) delta;
+                if ((unsigned long) delta > tscmax)
+                        tscmax = (unsigned int) delta;
+                pitcnt++;
+        }
 
         /*
-         * Preset the result with the raw and inaccurate PIT
-         * calibration value
+         * Sanity checks:
+         *
+         * If we were not able to read the PIT more than 5000
+         * times, then we have been hit by a massive SMI
+         *
+         * If the maximum is 10 times larger than the minimum,
+         * then we got hit by an SMI as well.
          */
-        delta = (tr2 - tr1);
+        if (pitcnt < 5000 || tscmax > 10 * tscmin)
+                return ULONG_MAX;
+
+        /* Calculate the PIT value */
+        delta = t2 - t1;
         do_div(delta, 50);
-        tsc_khz_val = delta;
+        return delta;
+}
+
+
+/**
+ * native_calibrate_tsc - calibrate the tsc on boot
+ */
+unsigned long native_calibrate_tsc(void)
+{
+        u64 tsc1, tsc2, delta, pm1, pm2, hpet1, hpet2;
+        unsigned long tsc_pit_min = ULONG_MAX, tsc_ref_min = ULONG_MAX;
+        unsigned long flags;
+        int hpet = is_hpet_enabled(), i;
 
-        /* hpet or pmtimer available ? */
+        /*
+         * Run 5 calibration loops to get the lowest frequency value
+         * (the best estimate). We use two different calibration modes
+         * here:
+         *
+         * 1) PIT loop. We set the PIT Channel 2 to oneshot mode and
+         * load a timeout of 50ms. We read the time right after we
+         * started the timer and wait until the PIT count down reaches
+         * zero. In each wait loop iteration we read the TSC and check
+         * the delta to the previous read. We keep track of the min
+         * and max values of that delta. The delta is mostly defined
+         * by the IO time of the PIT access, so we can detect when a
+         * SMI/SMM disturbance happend between the two reads. If the
+         * maximum time is significantly larger than the minimum time,
+         * then we discard the result and have another try.
+         *
+         * 2) Reference counter. If available we use the HPET or the
+         * PMTIMER as a reference to check the sanity of that value.
+         * We use separate TSC readouts and check inside of the
+         * reference read for a SMI/SMM disturbance. We dicard
+         * disturbed values here as well. We do that around the PIT
+         * calibration delay loop as we have to wait for a certain
+         * amount of time anyway.
+         */
+        for (i = 0; i < 5; i++) {
+                unsigned long tsc_pit_khz;
+
+                /*
+                 * Read the start value and the reference count of
+                 * hpet/pmtimer when available. Then do the PIT
+                 * calibration, which will take at least 50ms, and
+                 * read the end value.
+                 */
+                local_irq_save(flags);
+                tsc1 = tsc_read_refs(&pm1, hpet ? &hpet1 : NULL);
+                tsc_pit_khz = pit_calibrate_tsc();
+                tsc2 = tsc_read_refs(&pm2, hpet ? &hpet2 : NULL);
+                local_irq_restore(flags);
+
+                /* Pick the lowest PIT TSC calibration so far */
+                tsc_pit_min = min(tsc_pit_min, tsc_pit_khz);
+
+                /* hpet or pmtimer available ? */
+                if (!hpet && !pm1 && !pm2)
+                        continue;
+
+                /* Check, whether the sampling was disturbed by an SMI */
+                if (tsc1 == ULLONG_MAX || tsc2 == ULLONG_MAX)
+                        continue;
+
+                tsc2 = (tsc2 - tsc1) * 1000000LL;
+
+                if (hpet) {
+                        if (hpet2 < hpet1)
+                                hpet2 += 0x100000000ULL;
+                        hpet2 -= hpet1;
+                        tsc1 = ((u64)hpet2 * hpet_readl(HPET_PERIOD));
+                        do_div(tsc1, 1000000);
+                } else {
+                        if (pm2 < pm1)
+                                pm2 += (u64)ACPI_PM_OVRRUN;
+                        pm2 -= pm1;
+                        tsc1 = pm2 * 1000000000LL;
+                        do_div(tsc1, PMTMR_TICKS_PER_SEC);
+                }
+
+                do_div(tsc2, tsc1);
+                tsc_ref_min = min(tsc_ref_min, (unsigned long) tsc2);
+        }
+
+        /*
+         * Now check the results.
+         */
+        if (tsc_pit_min == ULONG_MAX) {
+                /* PIT gave no useful value */
+                printk(KERN_WARNING "TSC: PIT calibration failed due to "
+                       "SMI disturbance.\n");
+
+                /* We don't have an alternative source, disable TSC */
+                if (!hpet && !pm1 && !pm2) {
+                        printk("TSC: No reference (HPET/PMTIMER) available\n");
+                        return 0;
+                }
+
+                /* The alternative source failed as well, disable TSC */
+                if (tsc_ref_min == ULONG_MAX) {
+                        printk(KERN_WARNING "TSC: HPET/PMTIMER calibration "
+                               "failed due to SMI disturbance.\n");
+                        return 0;
+                }
+
+                /* Use the alternative source */
+                printk(KERN_INFO "TSC: using %s reference calibration\n",
+                       hpet ? "HPET" : "PMTIMER");
+
+                return tsc_ref_min;
+        }
+
+        /* We don't have an alternative source, use the PIT calibration value */
         if (!hpet && !pm1 && !pm2) {
-                printk(KERN_INFO "TSC calibrated against PIT\n");
-                goto out;
+                printk(KERN_INFO "TSC: Using PIT calibration value\n");
+                return tsc_pit_min;
         }
 
-        /* Check, whether the sampling was disturbed by an SMI */
-        if (tsc1 == ULLONG_MAX || tsc2 == ULLONG_MAX) {
-                printk(KERN_WARNING "TSC calibration disturbed by SMI, "
-                                "using PIT calibration result\n");
-                goto out;
+        /* The alternative source failed, use the PIT calibration value */
+        if (tsc_ref_min == ULONG_MAX) {
+                printk(KERN_WARNING "TSC: HPET/PMTIMER calibration failed due "
+                       "to SMI disturbance. Using PIT calibration\n");
+                return tsc_pit_min;
         }
 
-        tsc2 = (tsc2 - tsc1) * 1000000LL;
-
-        if (hpet) {
-                printk(KERN_INFO "TSC calibrated against HPET\n");
-                if (hpet2 < hpet1)
-                        hpet2 += 0x100000000ULL;
-                hpet2 -= hpet1;
-                tsc1 = ((u64)hpet2 * hpet_readl(HPET_PERIOD));
-                do_div(tsc1, 1000000);
-        } else {
-                printk(KERN_INFO "TSC calibrated against PM_TIMER\n");
-                if (pm2 < pm1)
-                        pm2 += (u64)ACPI_PM_OVRRUN;
-                pm2 -= pm1;
-                tsc1 = pm2 * 1000000000LL;
-                do_div(tsc1, PMTMR_TICKS_PER_SEC);
+        /* Check the reference deviation */
+        delta = ((u64) tsc_pit_min) * 100;
+        do_div(delta, tsc_ref_min);
+
+        /*
+         * If both calibration results are inside a 5% window, the we
+         * use the lower frequency of those as it is probably the
+         * closest estimate.
+         */
+        if (delta >= 95 && delta <= 105) {
+                printk(KERN_INFO "TSC: PIT calibration confirmed by %s.\n",
+                       hpet ? "HPET" : "PMTIMER");
+                printk(KERN_INFO "TSC: using %s calibration value\n",
+                       tsc_pit_min <= tsc_ref_min ? "PIT" :
+                       hpet ? "HPET" : "PMTIMER");
+                return tsc_pit_min <= tsc_ref_min ? tsc_pit_min : tsc_ref_min;
         }
 
-        do_div(tsc2, tsc1);
-        tsc_khz_val = tsc2;
+        printk(KERN_WARNING "TSC: PIT calibration deviates from %s: %lu %lu.\n",
+               hpet ? "HPET" : "PMTIMER", tsc_pit_min, tsc_ref_min);
 
-out:
-        return tsc_khz_val;
+        /*
+         * The calibration values differ too much. In doubt, we use
+         * the PIT value as we know that there are PMTIMERs around
+         * running at double speed.
+         */
+        printk(KERN_INFO "TSC: Using PIT calibration value\n");
+        return tsc_pit_min;
 }
 
-
 #ifdef CONFIG_X86_32
 /* Only called from the Powernow K7 cpu freq driver */
 int recalibrate_cpu_khz(void)
diff --git a/arch/x86/kvm/paging_tmpl.h b/arch/x86/kvm/paging_tmpl.h
index f72ac1fa35f0..4a814bff21f2 100644
--- a/arch/x86/kvm/paging_tmpl.h
+++ b/arch/x86/kvm/paging_tmpl.h
@@ -345,7 +345,7 @@ static u64 *FNAME(fetch)(struct kvm_vcpu *vcpu, gva_t addr,
                 shadow_addr = __pa(shadow_page->spt);
                 shadow_pte = shadow_addr | PT_PRESENT_MASK | PT_ACCESSED_MASK
                         | PT_WRITABLE_MASK | PT_USER_MASK;
-                *shadow_ent = shadow_pte;
+                set_shadow_pte(shadow_ent, shadow_pte);
         }
 
         mmu_set_spte(vcpu, shadow_ent, access, walker->pte_access & access,
diff --git a/arch/x86/pci/i386.c b/arch/x86/pci/i386.c
index d765da913842..8791fc55e715 100644
--- a/arch/x86/pci/i386.c
+++ b/arch/x86/pci/i386.c
@@ -31,11 +31,8 @@
 #include <linux/ioport.h>
 #include <linux/errno.h>
 #include <linux/bootmem.h>
-#include <linux/acpi.h>
 
 #include <asm/pat.h>
-#include <asm/hpet.h>
-#include <asm/io_apic.h>
 
 #include "pci.h"
 
@@ -80,77 +77,6 @@ pcibios_align_resource(void *data, struct resource *res,
 }
 EXPORT_SYMBOL(pcibios_align_resource);
 
-static int check_res_with_valid(struct pci_dev *dev, struct resource *res)
-{
-        unsigned long base;
-        unsigned long size;
-        int i;
-
-        base = res->start;
-        size = (res->start == 0 && res->end == res->start) ? 0 :
-                 (res->end - res->start + 1);
-
-        if (!base || !size)
-                return 0;
-
-#ifdef CONFIG_HPET_TIMER
-        /* for hpet */
-        if (base == hpet_address && (res->flags & IORESOURCE_MEM)) {
-                dev_info(&dev->dev, "BAR has HPET at %08lx-%08lx\n",
-                                 base, base + size - 1);
-                return 1;
-        }
-#endif
-
-#ifdef CONFIG_X86_IO_APIC
-        for (i = 0; i < nr_ioapics; i++) {
-                unsigned long ioapic_phys = mp_ioapics[i].mp_apicaddr;
-
-                if (base == ioapic_phys && (res->flags & IORESOURCE_MEM)) {
-                        dev_info(&dev->dev, "BAR has ioapic at %08lx-%08lx\n",
-                                         base, base + size - 1);
-                        return 1;
-                }
-        }
-#endif
-
-#ifdef CONFIG_PCI_MMCONFIG
-        for (i = 0; i < pci_mmcfg_config_num; i++) {
-                unsigned long addr;
-
-                addr = pci_mmcfg_config[i].address;
-                if (base == addr && (res->flags & IORESOURCE_MEM)) {
-                        dev_info(&dev->dev, "BAR has MMCONFIG at %08lx-%08lx\n",
-                                         base, base + size - 1);
-                        return 1;
-                }
-        }
-#endif
-
-        return 0;
-}
-
-static int check_platform(struct pci_dev *dev, struct resource *res)
-{
-        struct resource *root = NULL;
-
-        /*
-         * forcibly insert it into the
-         * resource tree
-         */
-        if (res->flags & IORESOURCE_MEM)
-                root = &iomem_resource;
-        else if (res->flags & IORESOURCE_IO)
-                root = &ioport_resource;
-
-        if (root && check_res_with_valid(dev, res)) {
-                insert_resource(root, res);
-
-                return 1;
-        }
-
-        return 0;
-}
 /*
  *  Handle resources of PCI devices.  If the world were perfect, we could
  *  just allocate all the resource regions and do nothing more.  It isn't.
@@ -202,10 +128,7 @@ static void __init pcibios_allocate_bus_resources(struct list_head *bus_list)
                                 pr = pci_find_parent_resource(dev, r);
                                 if (!r->start || !pr ||
                                     request_resource(pr, r) < 0) {
-                                        if (check_platform(dev, r))
-                                                continue;
-                                        dev_err(&dev->dev, "BAR %d: can't "
-                                                "allocate resource\n", idx);
+                                        dev_err(&dev->dev, "BAR %d: can't allocate resource\n", idx);
                                         /*
                                          * Something is wrong with the region.
                                          * Invalidate the resource to prevent
@@ -240,17 +163,13 @@ static void __init pcibios_allocate_resources(int pass)
                         else
                                 disabled = !(command & PCI_COMMAND_MEMORY);
                         if (pass == disabled) {
-                                dev_dbg(&dev->dev, "resource %#08llx-%#08llx "
-                                        "(f=%lx, d=%d, p=%d)\n",
+                                dev_dbg(&dev->dev, "resource %#08llx-%#08llx (f=%lx, d=%d, p=%d)\n",
                                         (unsigned long long) r->start,
                                         (unsigned long long) r->end,
                                         r->flags, disabled, pass);
                                 pr = pci_find_parent_resource(dev, r);
                                 if (!pr || request_resource(pr, r) < 0) {
-                                        if (check_platform(dev, r))
-                                                continue;
-                                        dev_err(&dev->dev, "BAR %d: can't "
-                                                "allocate resource\n", idx);
+                                        dev_err(&dev->dev, "BAR %d: can't allocate resource\n", idx);
                                         /* We'll assign a new address later */
                                         r->end -= r->start;
                                         r->start = 0;