From: Felipe Contreras <felipe.contreras@xxxxxxxxx>
We need to protect not only the dmm_map list, but the individual
map_obj's, otherwise, we might be building the scatter-gather list with
garbage. So, use the existing proc_lock for that.
I observed race conditions which caused kernel panics while running
stress tests, also, Tuomas Kulve found it happening quite often in
Gumstix Over. This patch fixes those.
Cc: Tuomas Kulve <tuomas@xxxxxxxx>
Signed-off-by: Felipe Contreras <felipe.contreras@xxxxxxxxx>
Signed-off-by: Omar Ramirez Luna <omar.ramirez@xxxxxx>
Cc: stable <stable@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxx>
---
drivers/staging/tidspbridge/rmgr/proc.c | 19 ++++++++++++++-----
1 files changed, 14 insertions(+), 5 deletions(-)
diff --git a/drivers/staging/tidspbridge/rmgr/proc.c b/drivers/staging/tidspbridge/rmgr/proc.c
index 54f6133..c4e5c4e 100644
--- a/drivers/staging/tidspbridge/rmgr/proc.c
+++ b/drivers/staging/tidspbridge/rmgr/proc.c
@@ -779,12 +779,14 @@ int proc_begin_dma(void *hprocessor, void *pmpu_addr, u32 ul_size,
(u32)pmpu_addr,
ul_size, dir);
+ mutex_lock(&proc_lock);
+
/* find requested memory are in cached mapping information */
map_obj = find_containing_mapping(pr_ctxt, (u32) pmpu_addr, ul_size);
if (!map_obj) {
pr_err("%s: find_containing_mapping failed\n", __func__);
status = -EFAULT;
- goto err_out;
+ goto no_map;
}
if (memory_give_ownership(map_obj, (u32) pmpu_addr, ul_size, dir)) {
@@ -793,6 +795,8 @@ int proc_begin_dma(void *hprocessor, void *pmpu_addr, u32 ul_size,
status = -EFAULT;
}
+no_map:
+ mutex_unlock(&proc_lock);
err_out:
return status;
@@ -817,21 +821,24 @@ int proc_end_dma(void *hprocessor, void *pmpu_addr, u32 ul_size,
(u32)pmpu_addr,
ul_size, dir);
+ mutex_lock(&proc_lock);
+
/* find requested memory are in cached mapping information */
map_obj = find_containing_mapping(pr_ctxt, (u32) pmpu_addr, ul_size);
if (!map_obj) {
pr_err("%s: find_containing_mapping failed\n", __func__);
status = -EFAULT;
- goto err_out;
+ goto no_map;
}
if (memory_regain_ownership(map_obj, (u32) pmpu_addr, ul_size, dir)) {
pr_err("%s: InValid address parameters %p %x\n",
__func__, pmpu_addr, ul_size);
status = -EFAULT;
- goto err_out;
}
+no_map:
+ mutex_unlock(&proc_lock);
err_out:
return status;
}
@@ -1724,9 +1731,8 @@ int proc_un_map(void *hprocessor, void *map_addr,
(p_proc_object->bridge_context, va_align, size_align);
}
- mutex_unlock(&proc_lock);
if (status)
- goto func_end;
+ goto unmap_failed;
/*
* A successful unmap should be followed by removal of map_obj
@@ -1735,6 +1741,9 @@ int proc_un_map(void *hprocessor, void *map_addr,
*/
remove_mapping_information(pr_ctxt, (u32) map_addr, size_align);
+unmap_failed:
+ mutex_unlock(&proc_lock);
+
func_end:
dev_dbg(bridge, "%s: hprocessor: 0x%p map_addr: 0x%p status: 0x%x\n",
__func__, hprocessor, map_addr, status);
--
1.7.4.1
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