diff options
| -rw-r--r-- | hw/i386/intel_iommu.c | 15 |
1 files changed, 15 insertions, 0 deletions
diff --git a/hw/i386/intel_iommu.c b/hw/i386/intel_iommu.c index a7bf87a..3a5bb0b 100644 --- a/hw/i386/intel_iommu.c +++ b/hw/i386/intel_iommu.c @@ -957,6 +957,8 @@ static bool vtd_dev_pt_enabled(VTDAddressSpace *as) static bool vtd_switch_address_space(VTDAddressSpace *as) { bool use_iommu; + /* Whether we need to take the BQL on our own */ + bool take_bql = !qemu_mutex_iothread_locked(); assert(as); @@ -967,6 +969,15 @@ static bool vtd_switch_address_space(VTDAddressSpace *as) VTD_PCI_FUNC(as->devfn), use_iommu); + /* + * It's possible that we reach here without BQL, e.g., when called + * from vtd_pt_enable_fast_path(). However the memory APIs need + * it. We'd better make sure we have had it already, or, take it. + */ + if (take_bql) { + qemu_mutex_lock_iothread(); + } + /* Turn off first then on the other */ if (use_iommu) { memory_region_set_enabled(&as->sys_alias, false); @@ -976,6 +987,10 @@ static bool vtd_switch_address_space(VTDAddressSpace *as) memory_region_set_enabled(&as->sys_alias, true); } + if (take_bql) { + qemu_mutex_unlock_iothread(); + } + return use_iommu; } |