| Message ID | 1542276484-25508-2-git-send-email-wei.w.wang@intel.com |
|---|---|
| State | New |
| Headers | show |
| Series | virtio-balloon: free page hint support | expand |
diff --git a/include/qemu/bitmap.h b/include/qemu/bitmap.h index 509eedd..679f1bd 100644 --- a/include/qemu/bitmap.h +++ b/include/qemu/bitmap.h @@ -221,6 +221,10 @@ static inline int bitmap_intersects(const unsigned long *src1, static inline long bitmap_count_one(const unsigned long *bitmap, long nbits) { + if (unlikely(!nbits)) { + return 0; + } + if (small_nbits(nbits)) { return ctpopl(*bitmap & BITMAP_LAST_WORD_MASK(nbits)); } else {
BITMAP_LAST_WORD_MASK(nbits) returns 0xffffffff when "nbits=0", which makes bitmap_count_one fail to handle the "nbits=0" case. It appears to be preferred to remain BITMAP_LAST_WORD_MASK identical to the kernel implementation that it is ported from. So this patch fixes bitmap_count_one to handle the nbits=0 case. Inital Discussion Link: https://www.mail-archive.com/qemu-devel@nongnu.org/msg554316.html Signed-off-by: Wei Wang <wei.w.wang@intel.com> CC: Juan Quintela <quintela@redhat.com> CC: Dr. David Alan Gilbert <dgilbert@redhat.com> CC: Peter Xu <peterx@redhat.com> --- include/qemu/bitmap.h | 4 ++++ 1 file changed, 4 insertions(+)