Hi Robin, On 09/02/16 11:04, Robin Murphy wrote: > The existing msi-map code is fine for shifting the entire RID space > upwards, but attempting finer-grained remapping reveals a bug. It turns > out that we are mistakenly treating the msi-base part as an offset, not > as a new base to remap onto, so things get squiffy when rid-base is > nonzero. Fix this, and at the same time add a sanity check against > having msi-map-mask clash with a nonzero rid-base, as that's another > thing one can easily get wrong. > > CC: <stable@xxxxxxxxxxxxxxx> > Signed-off-by: Robin Murphy <robin.murphy@xxxxxxx> Looks like Stuart and you both found the same bug at the same time: https://lkml.org/lkml/2016/2/8/1066 but yours seem more correct to me (the rid_base masking in Stuart's version seems odd). > --- > drivers/of/irq.c | 9 ++++++++- > 1 file changed, 8 insertions(+), 1 deletion(-) > > diff --git a/drivers/of/irq.c b/drivers/of/irq.c > index 7ee21ae..e7bfc17 100644 > --- a/drivers/of/irq.c > +++ b/drivers/of/irq.c > @@ -635,6 +635,13 @@ static u32 __of_msi_map_rid(struct device *dev, struct device_node **np, > msi_base = be32_to_cpup(msi_map + 2); > rid_len = be32_to_cpup(msi_map + 3); > > + if (rid_base & ~map_mask) { > + dev_err(parent_dev, > + "Invalid msi-map translation - msi-map-mask (0x%x) ignores rid-base (0x%x)\n", > + map_mask, rid_base); > + return rid_out; > + } > + > msi_controller_node = of_find_node_by_phandle(phandle); > > matched = (masked_rid >= rid_base && > @@ -654,7 +661,7 @@ static u32 __of_msi_map_rid(struct device *dev, struct device_node **np, > if (!matched) > return rid_out; > > - rid_out = masked_rid + msi_base; > + rid_out = masked_rid - rid_base + msi_base; > dev_dbg(dev, > "msi-map at: %s, using mask %08x, rid-base: %08x, msi-base: %08x, length: %08x, rid: %08x -> %08x\n", > dev_name(parent_dev), map_mask, rid_base, msi_base, > Reviewed-by: Marc Zyngier <marc.zyngier@xxxxxxx> M. -- Jazz is not dead. It just smells funny... -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html