From 3145fcb6057c82e9d8b57bf86494df6af844c732 Mon Sep 17 00:00:00 2001 From: David Gibson Date: Wed, 4 Apr 2012 11:15:54 +1000 Subject: [PATCH] kvm: Fix dirty tracking with large kernel page size If the kernel page size is larger than TARGET_PAGE_SIZE, which happens for example on ppc64 with kernels compiled for 64K pages, the dirty tracking doesn't work. Signed-off-by: Benjamin Herrenschmidt Signed-off-by: David Gibson Signed-off-by: Avi Kivity --- kvm-all.c | 14 ++++++++++++-- 1 file changed, 12 insertions(+), 2 deletions(-) diff --git a/kvm-all.c b/kvm-all.c index b8e9dc6..9b73ccf 100644 --- a/kvm-all.c +++ b/kvm-all.c @@ -348,6 +348,7 @@ static int kvm_get_dirty_pages_log_range(MemoryRegionSection *section, unsigned long page_number, c; target_phys_addr_t addr, addr1; unsigned int len = ((section->size / TARGET_PAGE_SIZE) + HOST_LONG_BITS - 1) / HOST_LONG_BITS; + unsigned long hpratio = getpagesize() / TARGET_PAGE_SIZE; /* * bitmap-traveling is faster than memory-traveling (for addr...) @@ -359,10 +360,11 @@ static int kvm_get_dirty_pages_log_range(MemoryRegionSection *section, do { j = ffsl(c) - 1; c &= ~(1ul << j); - page_number = i * HOST_LONG_BITS + j; + page_number = (i * HOST_LONG_BITS + j) * hpratio; addr1 = page_number * TARGET_PAGE_SIZE; addr = section->offset_within_region + addr1; - memory_region_set_dirty(section->mr, addr, TARGET_PAGE_SIZE); + memory_region_set_dirty(section->mr, addr, + TARGET_PAGE_SIZE * hpratio); } while (c != 0); } } @@ -980,6 +982,14 @@ int kvm_init(void) s = g_malloc0(sizeof(KVMState)); + /* + * On systems where the kernel can support different base page + * sizes, host page size may be different from TARGET_PAGE_SIZE, + * even with KVM. TARGET_PAGE_SIZE is assumed to be the minimum + * page size for the system though. + */ + assert(TARGET_PAGE_SIZE <= getpagesize()); + #ifdef KVM_CAP_SET_GUEST_DEBUG QTAILQ_INIT(&s->kvm_sw_breakpoints); #endif -- 2.7.4