diff options
Diffstat (limited to 'arch/x86/mm/kmmio.c')
| -rw-r--r-- | arch/x86/mm/kmmio.c | 13 |
1 files changed, 11 insertions, 2 deletions
diff --git a/arch/x86/mm/kmmio.c b/arch/x86/mm/kmmio.c index 6a92d9111b6..93b1797666c 100644 --- a/arch/x86/mm/kmmio.c +++ b/arch/x86/mm/kmmio.c @@ -351,11 +351,19 @@ static void release_kmmio_fault_page(unsigned long page, } } +/* + * With page-unaligned ioremaps, one or two armed pages may contain + * addresses from outside the intended mapping. Events for these addresses + * are currently silently dropped. The events may result only from programming + * mistakes by accessing addresses before the beginning or past the end of a + * mapping. + */ int register_kmmio_probe(struct kmmio_probe *p) { unsigned long flags; int ret = 0; unsigned long size = 0; + const unsigned long size_lim = p->len + (p->addr & ~PAGE_MASK); spin_lock_irqsave(&kmmio_lock, flags); if (get_kmmio_probe(p->addr)) { @@ -364,7 +372,7 @@ int register_kmmio_probe(struct kmmio_probe *p) } kmmio_count++; list_add_rcu(&p->list, &kmmio_probes); - while (size < p->len) { + while (size < size_lim) { if (add_kmmio_fault_page(p->addr + size)) pr_err("kmmio: Unable to set page fault.\n"); size += PAGE_SIZE; @@ -436,11 +444,12 @@ void unregister_kmmio_probe(struct kmmio_probe *p) { unsigned long flags; unsigned long size = 0; + const unsigned long size_lim = p->len + (p->addr & ~PAGE_MASK); struct kmmio_fault_page *release_list = NULL; struct kmmio_delayed_release *drelease; spin_lock_irqsave(&kmmio_lock, flags); - while (size < p->len) { + while (size < size_lim) { release_kmmio_fault_page(p->addr + size, &release_list); size += PAGE_SIZE; } |