diff options
| author | Suman Anna <s-anna@ti.com> | 2014-10-23 02:22:34 +0400 |
|---|---|---|
| committer | Joerg Roedel <jroedel@suse.de> | 2014-10-23 16:33:48 +0400 |
| commit | c5cf5c5377fbd0a1ff2a09ad1f0c7e261aabc567 (patch) | |
| tree | ec305e6778337e821ca617e8b9286e86cec24d68 /drivers | |
| parent | f24d9ad3fafd7c4ee47ec75947657d768873b6e4 (diff) | |
| download | linux-c5cf5c5377fbd0a1ff2a09ad1f0c7e261aabc567.tar.xz | |
iommu/omap: Fix bus error on debugfs access of unattached IOMMU
Any debugfs access on an OMAP IOMMU that is not enabled (done during
attach) results in a bus error due to access of registers without
the clock or the reset enabled for the respective IOMMU. So, add a
check to make sure the IOMMU is enabled/attached by a client device.
This gracefully prints a "Operation not permitted" trace when the
corresponding IOMMU is not enabled.
Signed-off-by: Suman Anna <s-anna@ti.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/iommu/omap-iommu-debug.c | 14 |
1 files changed, 14 insertions, 0 deletions
diff --git a/drivers/iommu/omap-iommu-debug.c b/drivers/iommu/omap-iommu-debug.c index 4813d3a71a00..41b09a1d78ea 100644 --- a/drivers/iommu/omap-iommu-debug.c +++ b/drivers/iommu/omap-iommu-debug.c @@ -24,6 +24,11 @@ static DEFINE_MUTEX(iommu_debug_lock); static struct dentry *iommu_debug_root; +static inline bool is_omap_iommu_detached(struct omap_iommu *obj) +{ + return !obj->domain; +} + static ssize_t debug_read_regs(struct file *file, char __user *userbuf, size_t count, loff_t *ppos) { @@ -31,6 +36,9 @@ static ssize_t debug_read_regs(struct file *file, char __user *userbuf, char *p, *buf; ssize_t bytes; + if (is_omap_iommu_detached(obj)) + return -EPERM; + buf = kmalloc(count, GFP_KERNEL); if (!buf) return -ENOMEM; @@ -54,6 +62,9 @@ static ssize_t debug_read_tlb(struct file *file, char __user *userbuf, char *p, *buf; ssize_t bytes, rest; + if (is_omap_iommu_detached(obj)) + return -EPERM; + buf = kmalloc(count, GFP_KERNEL); if (!buf) return -ENOMEM; @@ -139,6 +150,9 @@ static ssize_t debug_read_pagetable(struct file *file, char __user *userbuf, char *p, *buf; size_t bytes; + if (is_omap_iommu_detached(obj)) + return -EPERM; + buf = (char *)__get_free_page(GFP_KERNEL); if (!buf) return -ENOMEM; |