6.6-stable review patch. If anyone has any objections, please let me know.
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From: Jinyang He hejinyang@loongson.cn
[ Upstream commit 97ceddbc9404a7d1e2c4049435bff29427d762cc ]
During unwinding, unwind_done() is used as an end condition. Normally it unwind to the user stack and then set the stack type to unknown, which is a normal exit. When something unexpected happens in unwind process and we cannot unwind anymore, we should set the error flag, and also set the stack type to unknown to indicate that the unwind process can not continue. The error flag emphasizes that the unwind process produce an unexpected error. There is no unexpected things when we unwind the PT_REGS in the top of IRQ stack and find out that is an user mode PT_REGS. Thus, we should not set error flag and just set stack type to unknown.
Reported-by: Hengqi Chen hengqi.chen@gmail.com Acked-by: Hengqi Chen hengqi.chen@gmail.com Signed-off-by: Jinyang He hejinyang@loongson.cn Signed-off-by: Huacai Chen chenhuacai@loongson.cn Signed-off-by: Sasha Levin sashal@kernel.org --- arch/loongarch/kernel/stacktrace.c | 2 +- arch/loongarch/kernel/unwind.c | 1 - arch/loongarch/kernel/unwind_prologue.c | 2 +- 3 files changed, 2 insertions(+), 3 deletions(-)
diff --git a/arch/loongarch/kernel/stacktrace.c b/arch/loongarch/kernel/stacktrace.c index 92270f14db94..f623feb2129f 100644 --- a/arch/loongarch/kernel/stacktrace.c +++ b/arch/loongarch/kernel/stacktrace.c @@ -32,7 +32,7 @@ void arch_stack_walk(stack_trace_consume_fn consume_entry, void *cookie, }
for (unwind_start(&state, task, regs); - !unwind_done(&state) && !unwind_error(&state); unwind_next_frame(&state)) { + !unwind_done(&state); unwind_next_frame(&state)) { addr = unwind_get_return_address(&state); if (!addr || !consume_entry(cookie, addr)) break; diff --git a/arch/loongarch/kernel/unwind.c b/arch/loongarch/kernel/unwind.c index ba324ba76fa1..a463d6961344 100644 --- a/arch/loongarch/kernel/unwind.c +++ b/arch/loongarch/kernel/unwind.c @@ -28,6 +28,5 @@ bool default_next_frame(struct unwind_state *state)
} while (!get_stack_info(state->sp, state->task, info));
- state->error = true; return false; } diff --git a/arch/loongarch/kernel/unwind_prologue.c b/arch/loongarch/kernel/unwind_prologue.c index 55afc27320e1..929ae240280a 100644 --- a/arch/loongarch/kernel/unwind_prologue.c +++ b/arch/loongarch/kernel/unwind_prologue.c @@ -227,7 +227,7 @@ static bool next_frame(struct unwind_state *state) } while (!get_stack_info(state->sp, state->task, info));
out: - state->error = true; + state->stack_info.type = STACK_TYPE_UNKNOWN; return false; }