diff options
| author | David Woodhouse <dwmw@amazon.co.uk> | 2020-09-24 15:08:42 +0100 |
|---|---|---|
| committer | Joerg Roedel <jroedel@suse.de> | 2020-10-07 11:49:54 +0200 |
| commit | c40aaaac1018ff1382f2d35df5129a6bcea3df6b (patch) | |
| tree | 25461ff1c1c8db82d2c95cb7f797290deccf987f /drivers/iommu | |
| parent | d2ef0962492c3be3563e53a431c285678849b3c1 (diff) | |
iommu/vt-d: Gracefully handle DMAR units with no supported address widths
Instead of bailing out completely, such a unit can still be used for
interrupt remapping.
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Reviewed-by: Lu Baolu <baolu.lu@linux.intel.com>
Link: https://lore.kernel.org/linux-iommu/549928db2de6532117f36c9c810373c14cf76f51.camel@infradead.org/
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Diffstat (limited to 'drivers/iommu')
| -rw-r--r-- | drivers/iommu/intel/dmar.c | 46 |
1 files changed, 31 insertions, 15 deletions
diff --git a/drivers/iommu/intel/dmar.c b/drivers/iommu/intel/dmar.c index ba47edf03941..54d790f75824 100644 --- a/drivers/iommu/intel/dmar.c +++ b/drivers/iommu/intel/dmar.c @@ -1024,8 +1024,8 @@ static int alloc_iommu(struct dmar_drhd_unit *drhd) { struct intel_iommu *iommu; u32 ver, sts; - int agaw = 0; - int msagaw = 0; + int agaw = -1; + int msagaw = -1; int err; if (!drhd->reg_base_addr) { @@ -1050,17 +1050,28 @@ static int alloc_iommu(struct dmar_drhd_unit *drhd) } err = -EINVAL; - agaw = iommu_calculate_agaw(iommu); - if (agaw < 0) { - pr_err("Cannot get a valid agaw for iommu (seq_id = %d)\n", - iommu->seq_id); - goto err_unmap; - } - msagaw = iommu_calculate_max_sagaw(iommu); - if (msagaw < 0) { - pr_err("Cannot get a valid max agaw for iommu (seq_id = %d)\n", - iommu->seq_id); - goto err_unmap; + if (cap_sagaw(iommu->cap) == 0) { + pr_info("%s: No supported address widths. Not attempting DMA translation.\n", + iommu->name); + drhd->ignored = 1; + } + + if (!drhd->ignored) { + agaw = iommu_calculate_agaw(iommu); + if (agaw < 0) { + pr_err("Cannot get a valid agaw for iommu (seq_id = %d)\n", + iommu->seq_id); + drhd->ignored = 1; + } + } + if (!drhd->ignored) { + msagaw = iommu_calculate_max_sagaw(iommu); + if (msagaw < 0) { + pr_err("Cannot get a valid max agaw for iommu (seq_id = %d)\n", + iommu->seq_id); + drhd->ignored = 1; + agaw = -1; + } } iommu->agaw = agaw; iommu->msagaw = msagaw; @@ -1087,7 +1098,12 @@ static int alloc_iommu(struct dmar_drhd_unit *drhd) raw_spin_lock_init(&iommu->register_lock); - if (intel_iommu_enabled) { + /* + * This is only for hotplug; at boot time intel_iommu_enabled won't + * be set yet. When intel_iommu_init() runs, it registers the units + * present at boot time, then sets intel_iommu_enabled. + */ + if (intel_iommu_enabled && !drhd->ignored) { err = iommu_device_sysfs_add(&iommu->iommu, NULL, intel_iommu_groups, "%s", iommu->name); @@ -1117,7 +1133,7 @@ error: static void free_iommu(struct intel_iommu *iommu) { - if (intel_iommu_enabled) { + if (intel_iommu_enabled && iommu->iommu.ops) { iommu_device_unregister(&iommu->iommu); iommu_device_sysfs_remove(&iommu->iommu); } |