On Mon, May 29, 2017 at 10:36:42AM +0530, Sricharan R wrote: > Hi Rafael, > > On 5/28/2017 12:48 AM, Rafael J. Wysocki wrote: > > On Saturday, May 27, 2017 07:17:42 PM Sricharan R wrote: > >> While deferring the probe of IOMMU masters, xlate and > >> add_device callbacks called from iort_iommu_configure > >> can pass back error values like -ENODEV, which means > >> the IOMMU cannot be connected with that master for real > >> reasons. Before the IOMMU probe deferral, all such errors > >> were ignored. Now all those errors are propagated back, > >> killing the master's probe for such errors. Instead ignore > >> all the errors except EPROBE_DEFER, which is the only one > >> of concern and let the master work without IOMMU, thus > >> restoring the old behavior. Also make explicit that > >> acpi_dma_configure handles only -EPROBE_DEFER from > >> iort_iommu_configure. > >> > >> Fixes: 5a1bb638d567 ("drivers: acpi: Handle IOMMU lookup failure with deferred probing or error") > >> Signed-off-by: Sricharan R <sricharan@xxxxxxxxxxxxxx> > >> --- > >> drivers/acpi/arm64/iort.c | 6 ++++++ > >> drivers/acpi/scan.c | 4 ++-- > >> 2 files changed, 8 insertions(+), 2 deletions(-) > >> > >> diff --git a/drivers/acpi/arm64/iort.c b/drivers/acpi/arm64/iort.c > >> index c5fecf9..16e101f 100644 > >> --- a/drivers/acpi/arm64/iort.c > >> +++ b/drivers/acpi/arm64/iort.c > >> @@ -782,6 +782,12 @@ const struct iommu_ops *iort_iommu_configure(struct device *dev) > >> if (err) > >> ops = ERR_PTR(err); > >> > >> + /* Ignore all other errors apart from EPROBE_DEFER */ > >> + if (IS_ERR(ops) && (PTR_ERR(ops) != -EPROBE_DEFER)) { > >> + dev_dbg(dev, "Adding to IOMMU failed: %ld\n", PTR_ERR(ops)); > >> + ops = NULL; > >> + } > >> + > >> return ops; > >> } > >> > >> diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c > >> index e39ec7b..3a10d757 100644 > >> --- a/drivers/acpi/scan.c > >> +++ b/drivers/acpi/scan.c > >> @@ -1371,8 +1371,8 @@ int acpi_dma_configure(struct device *dev, enum dev_dma_attr attr) > >> iort_set_dma_mask(dev); > >> > >> iommu = iort_iommu_configure(dev); > >> - if (IS_ERR(iommu)) > >> - return PTR_ERR(iommu); > >> + if (IS_ERR(iommu) && PTR_ERR(iommu) == -EPROBE_DEFER) > >> + return -EPROBE_DEFER; > >> > >> size = max(dev->coherent_dma_mask, dev->coherent_dma_mask + 1); > >> /* > >> > > > > ACK for the scan.c change and I'm assuming this to go in via ARM64. > > > > Thanks for the ACK, should go through the IOMMU tree, since this fixes the IOMMU probe deferral > that got merged through it. Yes and it would be good to get them merged for -rc4 given that there are bug fixes there, I agree the IOMMU tree is the way they should go upstream. Lorenzo -- To unsubscribe from this list: send the line "unsubscribe linux-arm-msm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html