Re: [PATCH 1/3] drm/amdkfd: Fix error handling in svm_range_add
On 2021-12-08 3:24 a.m., Felix Kuehling
wrote:
Add null-pointer check after the last svm_range_new call. This was
originally reported by Zhou Qingyang based on a
static analyzer.
To avoid duplicating the unwinding code from svm_range_handle_overlap,
I merged the two functions into one.
Signed-off-by: Felix Kuehling
Cc: Zhou Qingyang
Reviewed-by: Philip Yang
---
drivers/gpu/drm/amd/amdkfd/kfd_svm.c | 138 ++-
1 file changed, 49 insertions(+), 89 deletions(-)
diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_svm.c b/drivers/gpu/drm/amd/amdkfd/kfd_svm.c
index f2db49c7a8fd..ed4430e31307 100644
--- a/drivers/gpu/drm/amd/amdkfd/kfd_svm.c
+++ b/drivers/gpu/drm/amd/amdkfd/kfd_svm.c
@@ -941,7 +941,7 @@ svm_range_split(struct svm_range *prange, uint64_t start, uint64_t last,
}
static int
-svm_range_split_tail(struct svm_range *prange, struct svm_range *new,
+svm_range_split_tail(struct svm_range *prange,
uint64_t new_last, struct list_head *insert_list)
{
struct svm_range *tail;
@@ -953,7 +953,7 @@ svm_range_split_tail(struct svm_range *prange, struct svm_range *new,
}
static int
-svm_range_split_head(struct svm_range *prange, struct svm_range *new,
+svm_range_split_head(struct svm_range *prange,
uint64_t new_start, struct list_head *insert_list)
{
struct svm_range *head;
@@ -1754,49 +1754,54 @@ static struct svm_range *svm_range_clone(struct svm_range *old)
}
/**
- * svm_range_handle_overlap - split overlap ranges
- * @svms: svm range list header
- * @new: range added with this attributes
- * @start: range added start address, in pages
- * @last: range last address, in pages
- * @update_list: output, the ranges attributes are updated. For set_attr, this
- * will do validation and map to GPUs. For unmap, this will be
- * removed and unmap from GPUs
- * @insert_list: output, the ranges will be inserted into svms, attributes are
- * not changes. For set_attr, this will add into svms.
- * @remove_list:output, the ranges will be removed from svms
- * @left: the remaining range after overlap, For set_attr, this will be added
- *as new range.
+ * svm_range_add - add svm range and handle overlap
+ * @p: the range add to this process svms
+ * @start: page size aligned
+ * @size: page size aligned
+ * @nattr: number of attributes
+ * @attrs: array of attributes
+ * @update_list: output, the ranges need validate and update GPU mapping
+ * @insert_list: output, the ranges need insert to svms
+ * @remove_list: output, the ranges are replaced and need remove from svms
*
- * Total have 5 overlap cases.
+ * Check if the virtual address range has overlap with any existing ranges,
+ * split partly overlapping ranges and add new ranges in the gaps. All changes
+ * should be applied to the range_list and interval tree transactionally. If
+ * any range split or allocation fails, the entire update fails. Therefore any
+ * existing overlapping svm_ranges are cloned and the original svm_ranges left
+ * unchanged.
*
- * This function handles overlap of an address interval with existing
- * struct svm_ranges for applying new attributes. This may require
- * splitting existing struct svm_ranges. All changes should be applied to
- * the range_list and interval tree transactionally. If any split operation
- * fails, the entire update fails. Therefore the existing overlapping
- * svm_ranges are cloned and the original svm_ranges left unchanged. If the
- * transaction succeeds, the modified clones are added and the originals
- * freed. Otherwise the clones are removed and the old svm_ranges remain.
+ * If the transaction succeeds, the caller can update and insert clones and
+ * new ranges, then free the originals.
*
- * Context: The caller must hold svms->lock
+ * Otherwise the caller can free the clones and new ranges, while the old
+ * svm_ranges remain unchanged.
+ *
+ * Context: Process context, caller must hold svms->lock
+ *
+ * Return:
+ * 0 - OK, otherwise error code
*/
static int
-svm_range_handle_overlap(struct svm_range_list *svms, struct svm_range *new,
- unsigned long start, unsigned long last,
- struct list_head *update_list,
- struct list_head *insert_list,
- struct list_head *remove_list,
- unsigned long *left)
+svm_range_add(struct kfd_process *p, uint64_t start, uint64_t size,
+ uint32_t nattr, struct kfd_ioctl_svm_attribute *attrs,
+ struct list_head *update_list, struct list_head *insert_list,
+ struct list_head *remove_list)
{
+ unsigned long last = start + size - 1UL;
+ struct svm_range_list *svms = >svms;
struct interval_tree_node *node;
+ struct svm_range new = {0};
struct svm_range *prange;
struct svm_range *tmp;
int r = 0;
+ pr_debug("svms 0x%p [0x%llx 0x%lx]\n", >svms, start, last);
+
INIT_LIST_HEAD(update_list);
INIT_LIST_HEAD(insert_list);
INIT_LIST_HEAD(remove_list);
+
[PATCH 1/3] drm/amdkfd: Fix error handling in svm_range_add
Add null-pointer check after the last svm_range_new call. This was
originally reported by Zhou Qingyang based on a
static analyzer.
To avoid duplicating the unwinding code from svm_range_handle_overlap,
I merged the two functions into one.
Signed-off-by: Felix Kuehling
Cc: Zhou Qingyang
---
drivers/gpu/drm/amd/amdkfd/kfd_svm.c | 138 ++-
1 file changed, 49 insertions(+), 89 deletions(-)
diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_svm.c
b/drivers/gpu/drm/amd/amdkfd/kfd_svm.c
index f2db49c7a8fd..ed4430e31307 100644
--- a/drivers/gpu/drm/amd/amdkfd/kfd_svm.c
+++ b/drivers/gpu/drm/amd/amdkfd/kfd_svm.c
@@ -941,7 +941,7 @@ svm_range_split(struct svm_range *prange, uint64_t start,
uint64_t last,
}
static int
-svm_range_split_tail(struct svm_range *prange, struct svm_range *new,
+svm_range_split_tail(struct svm_range *prange,
uint64_t new_last, struct list_head *insert_list)
{
struct svm_range *tail;
@@ -953,7 +953,7 @@ svm_range_split_tail(struct svm_range *prange, struct
svm_range *new,
}
static int
-svm_range_split_head(struct svm_range *prange, struct svm_range *new,
+svm_range_split_head(struct svm_range *prange,
uint64_t new_start, struct list_head *insert_list)
{
struct svm_range *head;
@@ -1754,49 +1754,54 @@ static struct svm_range *svm_range_clone(struct
svm_range *old)
}
/**
- * svm_range_handle_overlap - split overlap ranges
- * @svms: svm range list header
- * @new: range added with this attributes
- * @start: range added start address, in pages
- * @last: range last address, in pages
- * @update_list: output, the ranges attributes are updated. For set_attr, this
- * will do validation and map to GPUs. For unmap, this will be
- * removed and unmap from GPUs
- * @insert_list: output, the ranges will be inserted into svms, attributes are
- * not changes. For set_attr, this will add into svms.
- * @remove_list:output, the ranges will be removed from svms
- * @left: the remaining range after overlap, For set_attr, this will be added
- *as new range.
+ * svm_range_add - add svm range and handle overlap
+ * @p: the range add to this process svms
+ * @start: page size aligned
+ * @size: page size aligned
+ * @nattr: number of attributes
+ * @attrs: array of attributes
+ * @update_list: output, the ranges need validate and update GPU mapping
+ * @insert_list: output, the ranges need insert to svms
+ * @remove_list: output, the ranges are replaced and need remove from svms
*
- * Total have 5 overlap cases.
+ * Check if the virtual address range has overlap with any existing ranges,
+ * split partly overlapping ranges and add new ranges in the gaps. All changes
+ * should be applied to the range_list and interval tree transactionally. If
+ * any range split or allocation fails, the entire update fails. Therefore any
+ * existing overlapping svm_ranges are cloned and the original svm_ranges left
+ * unchanged.
*
- * This function handles overlap of an address interval with existing
- * struct svm_ranges for applying new attributes. This may require
- * splitting existing struct svm_ranges. All changes should be applied to
- * the range_list and interval tree transactionally. If any split operation
- * fails, the entire update fails. Therefore the existing overlapping
- * svm_ranges are cloned and the original svm_ranges left unchanged. If the
- * transaction succeeds, the modified clones are added and the originals
- * freed. Otherwise the clones are removed and the old svm_ranges remain.
+ * If the transaction succeeds, the caller can update and insert clones and
+ * new ranges, then free the originals.
*
- * Context: The caller must hold svms->lock
+ * Otherwise the caller can free the clones and new ranges, while the old
+ * svm_ranges remain unchanged.
+ *
+ * Context: Process context, caller must hold svms->lock
+ *
+ * Return:
+ * 0 - OK, otherwise error code
*/
static int
-svm_range_handle_overlap(struct svm_range_list *svms, struct svm_range *new,
-unsigned long start, unsigned long last,
-struct list_head *update_list,
-struct list_head *insert_list,
-struct list_head *remove_list,
-unsigned long *left)
+svm_range_add(struct kfd_process *p, uint64_t start, uint64_t size,
+ uint32_t nattr, struct kfd_ioctl_svm_attribute *attrs,
+ struct list_head *update_list, struct list_head *insert_list,
+ struct list_head *remove_list)
{
+ unsigned long last = start + size - 1UL;
+ struct svm_range_list *svms = >svms;
struct interval_tree_node *node;
+ struct svm_range new = {0};
struct svm_range *prange;
struct svm_range *tmp;
int r = 0;
+ pr_debug("svms 0x%p [0x%llx 0x%lx]\n", >svms, start, last);
+
INIT_LIST_HEAD(update_list);
