Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Thomas Gleixner:
"This set of updates contains:
- Another bugfix for the pathologic vm86 machinery. Clear
thread.vm86 on fork to prevent corrupting the parent state. This
comes along with an update to the vm86 selftest case
- Fix another corner case in the ioapic setup code which causes a
boot crash on some oddball systems
- Fix the fallout from the dma allocation consolidation work, which
leads to a NULL pointer dereference when the allocation code is
called with a NULL device"
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/vm86: Set thread.vm86 to NULL on fork/clone
selftests/x86: Add a fork() to entry_from_vm86 to catch fork bugs
x86/ioapic: Prevent NULL pointer dereference in setup_ioapic_dest()
x86/dma-mapping: Fix arch_dma_alloc_attrs() oops with NULL dev
diff --git a/arch/x86/kernel/apic/io_apic.c b/arch/x86/kernel/apic/io_apic.c
index bb6bfc0..4f28215 100644
--- a/arch/x86/kernel/apic/io_apic.c
+++ b/arch/x86/kernel/apic/io_apic.c
@@ -2547,7 +2547,9 @@
mask = apic->target_cpus();
chip = irq_data_get_irq_chip(idata);
- chip->irq_set_affinity(idata, mask, false);
+ /* Might be lapic_chip for irq 0 */
+ if (chip->irq_set_affinity)
+ chip->irq_set_affinity(idata, mask, false);
}
}
#endif
diff --git a/arch/x86/kernel/pci-dma.c b/arch/x86/kernel/pci-dma.c
index 1b55de1..cd99433 100644
--- a/arch/x86/kernel/pci-dma.c
+++ b/arch/x86/kernel/pci-dma.c
@@ -131,11 +131,12 @@
bool arch_dma_alloc_attrs(struct device **dev, gfp_t *gfp)
{
+ if (!*dev)
+ *dev = &x86_dma_fallback_dev;
+
*gfp &= ~(__GFP_DMA | __GFP_HIGHMEM | __GFP_DMA32);
*gfp = dma_alloc_coherent_gfp_flags(*dev, *gfp);
- if (!*dev)
- *dev = &x86_dma_fallback_dev;
if (!is_device_dma_capable(*dev))
return false;
return true;
diff --git a/arch/x86/kernel/process.c b/arch/x86/kernel/process.c
index e28db18..9f7c21c 100644
--- a/arch/x86/kernel/process.c
+++ b/arch/x86/kernel/process.c
@@ -84,6 +84,9 @@
int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src)
{
memcpy(dst, src, arch_task_struct_size);
+#ifdef CONFIG_VM86
+ dst->thread.vm86 = NULL;
+#endif
return fpu__copy(&dst->thread.fpu, &src->thread.fpu);
}
diff --git a/tools/testing/selftests/x86/entry_from_vm86.c b/tools/testing/selftests/x86/entry_from_vm86.c
index 421c607..d075ea0 100644
--- a/tools/testing/selftests/x86/entry_from_vm86.c
+++ b/tools/testing/selftests/x86/entry_from_vm86.c
@@ -230,5 +230,9 @@
}
clearhandler(SIGSEGV);
+ /* Make sure nothing explodes if we fork. */
+ if (fork() > 0)
+ return 0;
+
return (nerrs == 0 ? 0 : 1);
}