Commit 7fe67a11 authored by Linus Torvalds's avatar Linus Torvalds
Browse files

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

Pull leftover x86 fixes from Ingo Molnar:
 "Two leftover fixes that did not make it into v3.13"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86: Add check for number of available vectors before CPU down
  x86, cpu, amd: Add workaround for family 16h, erratum 793
parents fab5669d da6139e4
......@@ -25,6 +25,7 @@ extern void irq_ctx_init(int cpu);
#ifdef CONFIG_HOTPLUG_CPU
#include <linux/cpumask.h>
extern int check_irq_vectors_for_cpu_disable(void);
extern void fixup_irqs(void);
extern void irq_force_complete_move(int);
#endif
......
......@@ -184,6 +184,7 @@
#define MSR_AMD64_PATCH_LOADER 0xc0010020
#define MSR_AMD64_OSVW_ID_LENGTH 0xc0010140
#define MSR_AMD64_OSVW_STATUS 0xc0010141
#define MSR_AMD64_LS_CFG 0xc0011020
#define MSR_AMD64_DC_CFG 0xc0011022
#define MSR_AMD64_BU_CFG2 0xc001102a
#define MSR_AMD64_IBSFETCHCTL 0xc0011030
......
......@@ -507,6 +507,16 @@ static void early_init_amd(struct cpuinfo_x86 *c)
set_cpu_cap(c, X86_FEATURE_EXTD_APICID);
}
#endif
/* F16h erratum 793, CVE-2013-6885 */
if (c->x86 == 0x16 && c->x86_model <= 0xf) {
u64 val;
rdmsrl(MSR_AMD64_LS_CFG, val);
if (!(val & BIT(15)))
wrmsrl(MSR_AMD64_LS_CFG, val | BIT(15));
}
}
static const int amd_erratum_383[];
......
......@@ -266,6 +266,76 @@ __visible void smp_trace_x86_platform_ipi(struct pt_regs *regs)
EXPORT_SYMBOL_GPL(vector_used_by_percpu_irq);
#ifdef CONFIG_HOTPLUG_CPU
/*
* This cpu is going to be removed and its vectors migrated to the remaining
* online cpus. Check to see if there are enough vectors in the remaining cpus.
* This function is protected by stop_machine().
*/
int check_irq_vectors_for_cpu_disable(void)
{
int irq, cpu;
unsigned int this_cpu, vector, this_count, count;
struct irq_desc *desc;
struct irq_data *data;
struct cpumask affinity_new, online_new;
this_cpu = smp_processor_id();
cpumask_copy(&online_new, cpu_online_mask);
cpu_clear(this_cpu, online_new);
this_count = 0;
for (vector = FIRST_EXTERNAL_VECTOR; vector < NR_VECTORS; vector++) {
irq = __this_cpu_read(vector_irq[vector]);
if (irq >= 0) {
desc = irq_to_desc(irq);
data = irq_desc_get_irq_data(desc);
cpumask_copy(&affinity_new, data->affinity);
cpu_clear(this_cpu, affinity_new);
/* Do not count inactive or per-cpu irqs. */
if (!irq_has_action(irq) || irqd_is_per_cpu(data))
continue;
/*
* A single irq may be mapped to multiple
* cpu's vector_irq[] (for example IOAPIC cluster
* mode). In this case we have two
* possibilities:
*
* 1) the resulting affinity mask is empty; that is
* this the down'd cpu is the last cpu in the irq's
* affinity mask, or
*
* 2) the resulting affinity mask is no longer
* a subset of the online cpus but the affinity
* mask is not zero; that is the down'd cpu is the
* last online cpu in a user set affinity mask.
*/
if (cpumask_empty(&affinity_new) ||
!cpumask_subset(&affinity_new, &online_new))
this_count++;
}
}
count = 0;
for_each_online_cpu(cpu) {
if (cpu == this_cpu)
continue;
for (vector = FIRST_EXTERNAL_VECTOR; vector < NR_VECTORS;
vector++) {
if (per_cpu(vector_irq, cpu)[vector] < 0)
count++;
}
}
if (count < this_count) {
pr_warn("CPU %d disable failed: CPU has %u vectors assigned and there are only %u available.\n",
this_cpu, this_count, count);
return -ERANGE;
}
return 0;
}
/* A cpu has been removed from cpu_online_mask. Reset irq affinities. */
void fixup_irqs(void)
{
......
......@@ -1312,6 +1312,12 @@ void cpu_disable_common(void)
int native_cpu_disable(void)
{
int ret;
ret = check_irq_vectors_for_cpu_disable();
if (ret)
return ret;
clear_local_APIC();
cpu_disable_common();
......
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