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| author | Dmitry Torokhov <dmitry.torokhov@gmail.com> | 2019-09-16 09:56:27 -0700 |
|---|---|---|
| committer | Dmitry Torokhov <dmitry.torokhov@gmail.com> | 2019-09-16 09:56:27 -0700 |
| commit | 0898782247ae533d1f4e47a06bc5d4870931b284 (patch) | |
| tree | 21f75cc590542a870f42350b9410fc0588f02b79 /kernel/livepatch | |
| parent | 0c043d70d04711fe6c380df9065fdc44192c49bf (diff) | |
| parent | 410f25de467ee94c1a577c6ee7370c37b376c17c (diff) | |
Merge branch 'next' into for-linus
Prepare input updates for 5.4 merge window.
Diffstat (limited to 'kernel/livepatch')
| -rw-r--r-- | kernel/livepatch/transition.c | 11 |
1 files changed, 8 insertions, 3 deletions
diff --git a/kernel/livepatch/transition.c b/kernel/livepatch/transition.c index abb2a4a2cbb2..cdf318d86dd6 100644 --- a/kernel/livepatch/transition.c +++ b/kernel/livepatch/transition.c @@ -247,7 +247,6 @@ static int klp_check_stack(struct task_struct *task, char *err_buf) int ret, nr_entries; ret = stack_trace_save_tsk_reliable(task, entries, ARRAY_SIZE(entries)); - WARN_ON_ONCE(ret == -ENOSYS); if (ret < 0) { snprintf(err_buf, STACK_ERR_BUF_SIZE, "%s: %s:%d has an unreliable stack\n", @@ -281,11 +280,11 @@ static int klp_check_stack(struct task_struct *task, char *err_buf) */ static bool klp_try_switch_task(struct task_struct *task) { + static char err_buf[STACK_ERR_BUF_SIZE]; struct rq *rq; struct rq_flags flags; int ret; bool success = false; - char err_buf[STACK_ERR_BUF_SIZE]; err_buf[0] = '\0'; @@ -294,6 +293,13 @@ static bool klp_try_switch_task(struct task_struct *task) return true; /* + * For arches which don't have reliable stack traces, we have to rely + * on other methods (e.g., switching tasks at kernel exit). + */ + if (!klp_have_reliable_stack()) + return false; + + /* * Now try to check the stack for any to-be-patched or to-be-unpatched * functions. If all goes well, switch the task to the target patch * state. @@ -328,7 +334,6 @@ done: pr_debug("%s", err_buf); return success; - } /* |