Re: [Qemu-devel] [PULL 00/40] ivshmem: Fixes, cleanups, device model split

[Marcel Apfelbaum]

On 03/21/2016 02:11 PM, Markus Armbruster wrote:

Peter Maydell <peter.mayd...@linaro.org> writes:

[...]

Also some new clang ubsan warnings on x86 Linux:
GTESTER check-qtest-i386
[deleted existing warnings about slirp code]
/home/petmay01/linaro/qemu-for-merges/hw/pci/pci.c:166:23: runtime
error: shift exponent -1 is negative
/home/petmay01/linaro/qemu-for-merges/hw/pci/pci.c:171:24: runtime
error: shift exponent -1 is negative
/home/petmay01/linaro/qemu-for-merges/hw/pci/pci.c:172:24: runtime
error: shift exponent -1 is negative

Root cause tracked down with the appended patch.  PCI maintainers, you
might want to steal it.

Had anyone handled this already?

Thanks,
Marcel

diff --git a/hw/pci/pci.c b/hw/pci/pci.c
index e67664d..1937c42 100644
--- a/hw/pci/pci.c
+++ b/hw/pci/pci.c
@@ -163,11 +163,13 @@ int pci_bar(PCIDevice *d, int reg)

  static inline int pci_irq_state(PCIDevice *d, int irq_num)
  {
+    assert(irq_num >= 0);
        return (d->irq_state >> irq_num) & 0x1;
  }

  static inline void pci_set_irq_state(PCIDevice *d, int irq_num, int level)
  {
+    assert(irq_num >= 0);
        d->irq_state &= ~(0x1 << irq_num);
        d->irq_state |= level << irq_num;
  }