[GIT PULL] x86 fixes

Ingo Molnar
2016-04-28T18:00:43Z

Linus,

Please pull the latest x86-urgent-for-linus git tree from:

git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git x86-urgent-for-linus

# HEAD: 1bdb8970392a68489b469c3a330a1adb5ef61beb x86/apic: Handle zero vector gracefully in clear_vector_irq()

Two boot crash fixes and an IRQ handling crash fix.

Thanks,

Ingo

------------------>
Andy Lutomirski (1):
Revert "x86/mm/32: Set NX in __supported_pte_mask before enabling paging"

Keith Busch (1):
x86/apic: Handle zero vector gracefully in clear_vector_irq()

Ross Lagerwall (1):
xen/qspinlock: Don't kick CPU if IRQ is not initialized

arch/x86/kernel/apic/vector.c | 3 ++-
arch/x86/kernel/head_32.S | 6 ------
arch/x86/mm/setup_nx.c | 5 +++--
arch/x86/xen/spinlock.c | 6 ++++++
4 files changed, 11 insertions(+), 9 deletions(-)

diff --git a/arch/x86/kernel/apic/vector.c b/arch/x86/kernel/apic/vector.c
index ad59d70bcb1a..ef495511f019 100644
--- a/arch/x86/kernel/apic/vector.c
+++ b/arch/x86/kernel/apic/vector.c
@@ -256,7 +256,8 @@ static void clear_irq_vector(int irq, struct apic_chip_data *data)
struct irq_desc *desc;
int cpu, vector;

- BUG_ON(!data->cfg.vector);
+ if (!data->cfg.vector)
+ return;

vector = data->cfg.vector;
for_each_cpu_and(cpu, data->domain, cpu_online_mask)
diff --git a/arch/x86/kernel/head_32.S b/arch/x86/kernel/head_32.S
index 54cdbd2003fe..af1112980dd4 100644
--- a/arch/x86/kernel/head_32.S
+++ b/arch/x86/kernel/head_32.S
@@ -389,12 +389,6 @@ ENTRY(startup_32_smp)
/* Make changes effective */
wrmsr

- /*
- * And make sure that all the mappings we set up have NX set from
- * the beginning.
- */
- orl $(1 << (_PAGE_BIT_NX - 32)), pa(__supported_pte_mask + 4)
-
enable_paging:

/*
diff --git a/arch/x86/mm/setup_nx.c b/arch/x86/mm/setup_nx.c
index 8bea84724a7d..f65a33f505b6 100644
--- a/arch/x86/mm/setup_nx.c
+++ b/arch/x86/mm/setup_nx.c
@@ -32,8 +32,9 @@ early_param("noexec", noexec_setup);

void x86_configure_nx(void)
{
- /* If disable_nx is set, clear NX on all new mappings going forward. */
- if (disable_nx)
+ if (boot_cpu_has(X86_FEATURE_NX) && !disable_nx)
+ __supported_pte_mask |= _PAGE_NX;
+ else
__supported_pte_mask &= ~_PAGE_NX;
}

diff --git a/arch/x86/xen/spinlock.c b/arch/x86/xen/spinlock.c
index 9e2ba5c6e1dd..f42e78de1e10 100644
--- a/arch/x86/xen/spinlock.c
+++ b/arch/x86/xen/spinlock.c
@@ -27,6 +27,12 @@ static bool xen_pvspin = true;

static void xen_qlock_kick(int cpu)
{
+ int irq = per_cpu(lock_kicker_irq, cpu);
+
+ /* Don't kick if the target's kicker interrupt is not initialized. */
+ if (irq == -1)
+ return;
+
xen_send_IPI_one(cpu, XEN_SPIN_UNLOCK_VECTOR);
}