6.10-stable review patch. If anyone has any objections, please let me know.
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From: levi.yun yeoreum.yun@arm.com
commit 7dc836187f7c6f70a82b4521503e9f9f96194581 upstream.
pid_list_fill_irq() runs via irq_work. When CONFIG_PREEMPT_RT is disabled, it would run in irq_context. so it shouldn't sleep while memory allocation.
Change gfp flags from GFP_KERNEL to GFP_NOWAIT to prevent sleep in irq_work.
This change wouldn't impact functionality in practice because the worst-size is 2K.
Cc: stable@goodmis.org Fixes: 8d6e90983ade2 ("tracing: Create a sparse bitmask for pid filtering") Link: https://lore.kernel.org/20240704150226.1359936-1-yeoreum.yun@arm.com Acked-by: Masami Hiramatsu (Google) mhiramat@kernel.org Signed-off-by: levi.yun yeoreum.yun@arm.com Signed-off-by: Steven Rostedt (Google) rostedt@goodmis.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- kernel/trace/pid_list.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
--- a/kernel/trace/pid_list.c +++ b/kernel/trace/pid_list.c @@ -354,7 +354,7 @@ static void pid_list_refill_irq(struct i while (upper_count-- > 0) { union upper_chunk *chunk;
- chunk = kzalloc(sizeof(*chunk), GFP_KERNEL); + chunk = kzalloc(sizeof(*chunk), GFP_NOWAIT); if (!chunk) break; *upper_next = chunk; @@ -365,7 +365,7 @@ static void pid_list_refill_irq(struct i while (lower_count-- > 0) { union lower_chunk *chunk;
- chunk = kzalloc(sizeof(*chunk), GFP_KERNEL); + chunk = kzalloc(sizeof(*chunk), GFP_NOWAIT); if (!chunk) break; *lower_next = chunk;