Replace kzalloc with kvzalloc for the exit_dump buffer allocation, which can require large contiguous memory (up to order=9) depending on the implementation. This change prevents allocation failures by allowing the system to fall back to vmalloc when contiguous memory allocation fails.
Since this buffer is only used for debugging purposes, physical memory contiguity is not required, making vmalloc a suitable alternative.
Cc: stable@vger.kernel.org Fixes: 07814a9439a3b0 ("sched_ext: Print debug dump after an error exit") Suggested-by: Rik van Riel riel@surriel.com Signed-off-by: Breno Leitao leitao@debian.org --- kernel/sched/ext.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/kernel/sched/ext.c b/kernel/sched/ext.c index 66bcd40a28ca1..c82725f9b0559 100644 --- a/kernel/sched/ext.c +++ b/kernel/sched/ext.c @@ -4639,7 +4639,7 @@ static struct scx_exit_info *alloc_exit_info(size_t exit_dump_len)
ei->bt = kcalloc(SCX_EXIT_BT_LEN, sizeof(ei->bt[0]), GFP_KERNEL); ei->msg = kzalloc(SCX_EXIT_MSG_LEN, GFP_KERNEL); - ei->dump = kzalloc(exit_dump_len, GFP_KERNEL); + ei->dump = kvzalloc(exit_dump_len, GFP_KERNEL);
if (!ei->bt || !ei->msg || !ei->dump) { free_exit_info(ei);
--- base-commit: 0af2f6be1b4281385b618cb86ad946eded089ac8 change-id: 20250407-scx-11dbf94803c3
Best regards,
Le 07/04/2025 à 21:50, Breno Leitao a écrit :
Replace kzalloc with kvzalloc for the exit_dump buffer allocation, which can require large contiguous memory (up to order=9) depending on the implementation. This change prevents allocation failures by allowing the system to fall back to vmalloc when contiguous memory allocation fails.
Since this buffer is only used for debugging purposes, physical memory contiguity is not required, making vmalloc a suitable alternative.
Cc: stable@vger.kernel.org Fixes: 07814a9439a3b0 ("sched_ext: Print debug dump after an error exit") Suggested-by: Rik van Riel riel@surriel.com Signed-off-by: Breno Leitao leitao@debian.org
kernel/sched/ext.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/kernel/sched/ext.c b/kernel/sched/ext.c index 66bcd40a28ca1..c82725f9b0559 100644 --- a/kernel/sched/ext.c +++ b/kernel/sched/ext.c @@ -4639,7 +4639,7 @@ static struct scx_exit_info *alloc_exit_info(size_t exit_dump_len) ei->bt = kcalloc(SCX_EXIT_BT_LEN, sizeof(ei->bt[0]), GFP_KERNEL); ei->msg = kzalloc(SCX_EXIT_MSG_LEN, GFP_KERNEL);
- ei->dump = kzalloc(exit_dump_len, GFP_KERNEL);
- ei->dump = kvzalloc(exit_dump_len, GFP_KERNEL);
Needs kvfree() in free_exit_info()?
CJ
if (!ei->bt || !ei->msg || !ei->dump) { free_exit_info(ei);
base-commit: 0af2f6be1b4281385b618cb86ad946eded089ac8 change-id: 20250407-scx-11dbf94803c3
Best regards,
Hi Breno,
On Mon, Apr 07, 2025 at 12:50:29PM -0700, Breno Leitao wrote:
Replace kzalloc with kvzalloc for the exit_dump buffer allocation, which can require large contiguous memory (up to order=9) depending on the implementation. This change prevents allocation failures by allowing the system to fall back to vmalloc when contiguous memory allocation fails.
Since this buffer is only used for debugging purposes, physical memory contiguity is not required, making vmalloc a suitable alternative.
Cc: stable@vger.kernel.org Fixes: 07814a9439a3b0 ("sched_ext: Print debug dump after an error exit") Suggested-by: Rik van Riel riel@surriel.com Signed-off-by: Breno Leitao leitao@debian.org
Makes sense to me.
Acked-by: Andrea Righi arighi@nvidia.com
Thanks, -Andrea
kernel/sched/ext.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/kernel/sched/ext.c b/kernel/sched/ext.c index 66bcd40a28ca1..c82725f9b0559 100644 --- a/kernel/sched/ext.c +++ b/kernel/sched/ext.c @@ -4639,7 +4639,7 @@ static struct scx_exit_info *alloc_exit_info(size_t exit_dump_len) ei->bt = kcalloc(SCX_EXIT_BT_LEN, sizeof(ei->bt[0]), GFP_KERNEL); ei->msg = kzalloc(SCX_EXIT_MSG_LEN, GFP_KERNEL);
- ei->dump = kzalloc(exit_dump_len, GFP_KERNEL);
- ei->dump = kvzalloc(exit_dump_len, GFP_KERNEL);
if (!ei->bt || !ei->msg || !ei->dump) { free_exit_info(ei);
base-commit: 0af2f6be1b4281385b618cb86ad946eded089ac8 change-id: 20250407-scx-11dbf94803c3
Best regards,
Breno Leitao leitao@debian.org
Hi,
On 4/8/25 04:50, Breno Leitao wrote:
Replace kzalloc with kvzalloc for the exit_dump buffer allocation, which can require large contiguous memory (up to order=9) depending on the implementation. This change prevents allocation failures by allowing the system to fall back to vmalloc when contiguous memory allocation fails.
Since this buffer is only used for debugging purposes, physical memory contiguity is not required, making vmalloc a suitable alternative.
Cc: stable@vger.kernel.org Fixes: 07814a9439a3b0 ("sched_ext: Print debug dump after an error exit") Suggested-by: Rik van Riel riel@surriel.com Signed-off-by: Breno Leitao leitao@debian.org
kernel/sched/ext.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/kernel/sched/ext.c b/kernel/sched/ext.c index 66bcd40a28ca1..c82725f9b0559 100644 --- a/kernel/sched/ext.c +++ b/kernel/sched/ext.c @@ -4639,7 +4639,7 @@ static struct scx_exit_info *alloc_exit_info(size_t exit_dump_len) ei->bt = kcalloc(SCX_EXIT_BT_LEN, sizeof(ei->bt[0]), GFP_KERNEL); ei->msg = kzalloc(SCX_EXIT_MSG_LEN, GFP_KERNEL);
- ei->dump = kzalloc(exit_dump_len, GFP_KERNEL);
- ei->dump = kvzalloc(exit_dump_len, GFP_KERNEL);
if (!ei->bt || !ei->msg || !ei->dump) { free_exit_info(ei);
The change makes sense to me. But the kfree(ei->dump) in free_exit_info() also should be replaced with kvfree(ei->dump).
Regards, Changwoo Min
base-commit: 0af2f6be1b4281385b618cb86ad946eded089ac8 change-id: 20250407-scx-11dbf94803c3
Best regards,
linux-stable-mirror@lists.linaro.org
-
Andrea Righi -
Breno Leitao -
Changwoo Min -
Christophe JAILLET