diff options
| author | Douglas Anderson <dianders@chromium.org> | 2018-12-04 19:38:28 -0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2019-02-12 19:46:09 +0100 |
| commit | a67a554d53d627cd12232c15ef2b159808410ccb (patch) | |
| tree | 9ca9ddee1d7656321592275533fba2765689ee19 /kernel/debug/debug_core.c | |
| parent | 7bb72b163f989628bffa78bd2424b3c3a21f86c7 (diff) | |
kdb: Don't back trace on a cpu that didn't round up
[ Upstream commit 162bc7f5afd75b72acbe3c5f3488ef7e64a3fe36 ]
If you have a CPU that fails to round up and then run 'btc' you'll end
up crashing in kdb becaue we dereferenced NULL. Let's add a check.
It's wise to also set the task to NULL when leaving the debugger so
that if we fail to round up on a later entry into the debugger we
won't backtrace a stale task.
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Acked-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'kernel/debug/debug_core.c')
| -rw-r--r-- | kernel/debug/debug_core.c | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/kernel/debug/debug_core.c b/kernel/debug/debug_core.c index 65c0f1363788..94aa9ae0007a 100644 --- a/kernel/debug/debug_core.c +++ b/kernel/debug/debug_core.c @@ -535,6 +535,8 @@ return_normal: arch_kgdb_ops.correct_hw_break(); if (trace_on) tracing_on(); + kgdb_info[cpu].debuggerinfo = NULL; + kgdb_info[cpu].task = NULL; kgdb_info[cpu].exception_state &= ~(DCPU_WANT_MASTER | DCPU_IS_SLAVE); kgdb_info[cpu].enter_kgdb--; @@ -667,6 +669,8 @@ kgdb_restore: if (trace_on) tracing_on(); + kgdb_info[cpu].debuggerinfo = NULL; + kgdb_info[cpu].task = NULL; kgdb_info[cpu].exception_state &= ~(DCPU_WANT_MASTER | DCPU_IS_SLAVE); kgdb_info[cpu].enter_kgdb--; |