The commit bffac3c593eba1f9da3efd0199e49ea6558a40ce does: - temp = (1 << multi_msi_capable(control)); - temp = ((temp - 1) & ~temp); + temp = msi_mask((control & PCI_MSI_FLAGS_QMASK) >> 1); and provides msi_mask() to avoid undefined shift by 32. According to PCI Local Bus Spec 3.0 "6.8.1.3 Message Control for MSI", relations between the encoded bits in control register, the number of vectors and the proper maskbits should be as following table: control[3::1] | vectors | maskbits --------------+----------+----------- 000b | 1 | 0x1 001b | 2 | 0x3 010b | 4 | 0xf 011b | 8 | 0xff 100b | 16 | 0xffff 101b | 32 | 0xffffffff 110b | Reserved | n/a 111b | Reserved | n/a This patch fix the wrong array in the msi_mask(). Signed-off-by: Hidetoshi Seto <seto.hidetoshi@xxxxxxxxxxxxxx> --- drivers/pci/msi.c | 2 +- 1 files changed, 1 insertions(+), 1 deletions(-) diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c index 44f15ff..1c88958 100644 --- a/drivers/pci/msi.c +++ b/drivers/pci/msi.c @@ -109,7 +109,7 @@ static void msix_set_enable(struct pci_dev *dev, int enable) */ static inline __attribute_const__ u32 msi_mask(unsigned x) { - static const u32 mask[] = { 1, 2, 4, 0xf, 0xff, 0xffff, 0xffffffff }; + static const u32 mask[] = { 1, 3, 0xf, 0xff, 0xffff, 0xffffffff }; return mask[x]; } -- 1.6.0 -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html