diff options
| -rw-r--r-- | arch/arm64/Kconfig | 1 | ||||
| -rw-r--r-- | arch/arm64/kernel/process.c | 17 |
2 files changed, 18 insertions, 0 deletions
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index 8593ad10a9c4..7587cf86d941 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -199,6 +199,7 @@ config ARM64 select HAVE_SAMPLE_FTRACE_DIRECT_MULTI select HAVE_BUILDTIME_MCOUNT_SORT select HAVE_EFFICIENT_UNALIGNED_ACCESS + select HAVE_EXIT_THREAD select HAVE_GUP_FAST select HAVE_FTRACE_GRAPH_FUNC select HAVE_FUNCTION_TRACER diff --git a/arch/arm64/kernel/process.c b/arch/arm64/kernel/process.c index 581f80e9b9b7..42b15b0c069f 100644 --- a/arch/arm64/kernel/process.c +++ b/arch/arm64/kernel/process.c @@ -320,9 +320,18 @@ static int copy_thread_gcs(struct task_struct *p, return 0; } +static void gcs_reset_thread(struct task_struct *task) +{ + task->thread.gcs_base = 0; + task->thread.gcs_size = 0; + task->thread.gcspr_el0 = 0; +} + #else static void flush_gcs(void) { } +static void gcs_reset_thread(struct task_struct *task) { } + static int copy_thread_gcs(struct task_struct *p, const struct kernel_clone_args *args) { @@ -341,6 +350,12 @@ void flush_thread(void) flush_gcs(); } +void exit_thread(struct task_struct *tsk) +{ + /* Failed fork after copy_thread(); deactivate_mm() does not run. */ + gcs_free(tsk); +} + void arch_release_task_struct(struct task_struct *tsk) { fpsimd_release_task(tsk); @@ -503,6 +518,8 @@ int copy_thread(struct task_struct *p, const struct kernel_clone_args *args) p->thread.cpu_context.x19 = (unsigned long)args->fn; p->thread.cpu_context.x20 = (unsigned long)args->fn_arg; + /* Kernel threads sharing the parent's mm must not free its GCS. */ + gcs_reset_thread(p); if (system_supports_poe()) p->thread.por_el0 = POR_EL0_INIT; |