On Fri, Apr 29, 2022 at 4:57 PM 'Carlos Llamas' via kernel-team <kernel-team@xxxxxxxxxxx> wrote: > > Log readable and specific error messages whenever a transaction failure > happens. This will ensure better context is given to regular users about > these unique error cases, without having to decode a cryptic log. > > Signed-off-by: Carlos Llamas <cmllamas@xxxxxxxxxx> Acked-by: Todd Kjos <tkjos@xxxxxxxxxx> > --- > drivers/android/binder.c | 48 ++++++++++++++++++++++++++++++++++++---- > 1 file changed, 44 insertions(+), 4 deletions(-) > > diff --git a/drivers/android/binder.c b/drivers/android/binder.c > index bfb21e258427..d7c5e2dde270 100644 > --- a/drivers/android/binder.c > +++ b/drivers/android/binder.c > @@ -147,6 +147,9 @@ static __printf(2, 3) void binder_debug(int mask, const char *format, ...) > } > } > > +#define binder_txn_error(x...) \ > + binder_debug(BINDER_DEBUG_FAILED_TRANSACTION, x) > + > static __printf(1, 2) void binder_user_error(const char *format, ...) > { > struct va_format vaf; > @@ -2823,6 +2826,8 @@ static void binder_transaction(struct binder_proc *proc, > if (target_thread == NULL) { > /* annotation for sparse */ > __release(&target_thread->proc->inner_lock); > + binder_txn_error("%d:%d reply target not found\n", > + thread->pid, proc->pid); > return_error = BR_DEAD_REPLY; > return_error_line = __LINE__; > goto err_dead_binder; > @@ -2888,6 +2893,8 @@ static void binder_transaction(struct binder_proc *proc, > } > } > if (!target_node) { > + binder_txn_error("%d:%d cannot find target node\n", > + thread->pid, proc->pid); > /* > * return_error is set above > */ > @@ -2897,6 +2904,8 @@ static void binder_transaction(struct binder_proc *proc, > } > e->to_node = target_node->debug_id; > if (WARN_ON(proc == target_proc)) { > + binder_txn_error("%d:%d self transactions not allowed\n", > + thread->pid, proc->pid); > return_error = BR_FAILED_REPLY; > return_error_param = -EINVAL; > return_error_line = __LINE__; > @@ -2904,6 +2913,8 @@ static void binder_transaction(struct binder_proc *proc, > } > if (security_binder_transaction(proc->cred, > target_proc->cred) < 0) { > + binder_txn_error("%d:%d transaction credentials failed\n", > + thread->pid, proc->pid); > return_error = BR_FAILED_REPLY; > return_error_param = -EPERM; > return_error_line = __LINE__; > @@ -2975,6 +2986,8 @@ static void binder_transaction(struct binder_proc *proc, > /* TODO: reuse incoming transaction for reply */ > t = kzalloc(sizeof(*t), GFP_KERNEL); > if (t == NULL) { > + binder_txn_error("%d:%d cannot allocate transaction\n", > + thread->pid, proc->pid); > return_error = BR_FAILED_REPLY; > return_error_param = -ENOMEM; > return_error_line = __LINE__; > @@ -2986,6 +2999,8 @@ static void binder_transaction(struct binder_proc *proc, > > tcomplete = kzalloc(sizeof(*tcomplete), GFP_KERNEL); > if (tcomplete == NULL) { > + binder_txn_error("%d:%d cannot allocate work for transaction\n", > + thread->pid, proc->pid); > return_error = BR_FAILED_REPLY; > return_error_param = -ENOMEM; > return_error_line = __LINE__; > @@ -3032,6 +3047,8 @@ static void binder_transaction(struct binder_proc *proc, > security_cred_getsecid(proc->cred, &secid); > ret = security_secid_to_secctx(secid, &secctx, &secctx_sz); > if (ret) { > + binder_txn_error("%d:%d failed to get security context\n", > + thread->pid, proc->pid); > return_error = BR_FAILED_REPLY; > return_error_param = ret; > return_error_line = __LINE__; > @@ -3040,7 +3057,8 @@ static void binder_transaction(struct binder_proc *proc, > added_size = ALIGN(secctx_sz, sizeof(u64)); > extra_buffers_size += added_size; > if (extra_buffers_size < added_size) { > - /* integer overflow of extra_buffers_size */ > + binder_txn_error("%d:%d integer overflow of extra_buffers_size\n", > + thread->pid, proc->pid); > return_error = BR_FAILED_REPLY; > return_error_param = -EINVAL; > return_error_line = __LINE__; > @@ -3054,9 +3072,15 @@ static void binder_transaction(struct binder_proc *proc, > tr->offsets_size, extra_buffers_size, > !reply && (t->flags & TF_ONE_WAY), current->tgid); > if (IS_ERR(t->buffer)) { > - /* > - * -ESRCH indicates VMA cleared. The target is dying. > - */ > + char *s; > + > + ret = PTR_ERR(t->buffer); > + s = (ret == -ESRCH) ? ": vma cleared, target dead or dying" > + : (ret == -ENOSPC) ? ": no space left" > + : (ret == -ENOMEM) ? ": memory allocation failed" > + : ""; > + binder_txn_error("cannot allocate buffer%s", s); > + > return_error_param = PTR_ERR(t->buffer); > return_error = return_error_param == -ESRCH ? > BR_DEAD_REPLY : BR_FAILED_REPLY; > @@ -3139,6 +3163,8 @@ static void binder_transaction(struct binder_proc *proc, > t->buffer, > buffer_offset, > sizeof(object_offset))) { > + binder_txn_error("%d:%d copy offset from buffer failed\n", > + thread->pid, proc->pid); > return_error = BR_FAILED_REPLY; > return_error_param = -EINVAL; > return_error_line = __LINE__; > @@ -3197,6 +3223,8 @@ static void binder_transaction(struct binder_proc *proc, > t->buffer, > object_offset, > fp, sizeof(*fp))) { > + binder_txn_error("%d:%d translate binder failed\n", > + thread->pid, proc->pid); > return_error = BR_FAILED_REPLY; > return_error_param = ret; > return_error_line = __LINE__; > @@ -3214,6 +3242,8 @@ static void binder_transaction(struct binder_proc *proc, > t->buffer, > object_offset, > fp, sizeof(*fp))) { > + binder_txn_error("%d:%d translate handle failed\n", > + thread->pid, proc->pid); > return_error = BR_FAILED_REPLY; > return_error_param = ret; > return_error_line = __LINE__; > @@ -3234,6 +3264,8 @@ static void binder_transaction(struct binder_proc *proc, > t->buffer, > object_offset, > fp, sizeof(*fp))) { > + binder_txn_error("%d:%d translate fd failed\n", > + thread->pid, proc->pid); > return_error = BR_FAILED_REPLY; > return_error_param = ret; > return_error_line = __LINE__; > @@ -3303,6 +3335,8 @@ static void binder_transaction(struct binder_proc *proc, > object_offset, > fda, sizeof(*fda)); > if (ret) { > + binder_txn_error("%d:%d translate fd array failed\n", > + thread->pid, proc->pid); > return_error = BR_FAILED_REPLY; > return_error_param = ret > 0 ? -EINVAL : ret; > return_error_line = __LINE__; > @@ -3330,6 +3364,8 @@ static void binder_transaction(struct binder_proc *proc, > (const void __user *)(uintptr_t)bp->buffer, > bp->length); > if (ret) { > + binder_txn_error("%d:%d deferred copy failed\n", > + thread->pid, proc->pid); > return_error = BR_FAILED_REPLY; > return_error_param = ret; > return_error_line = __LINE__; > @@ -3353,6 +3389,8 @@ static void binder_transaction(struct binder_proc *proc, > t->buffer, > object_offset, > bp, sizeof(*bp))) { > + binder_txn_error("%d:%d failed to fixup parent\n", > + thread->pid, proc->pid); > return_error = BR_FAILED_REPLY; > return_error_param = ret; > return_error_line = __LINE__; > @@ -3460,6 +3498,8 @@ static void binder_transaction(struct binder_proc *proc, > return; > > err_dead_proc_or_thread: > + binder_txn_error("%d:%d dead process or thread\n", > + thread->pid, proc->pid); > return_error_line = __LINE__; > binder_dequeue_work(proc, tcomplete); > err_translate_failed: > -- > 2.36.0.464.gb9c8b46e94-goog > > -- > To unsubscribe from this group and stop receiving emails from it, send an email to kernel-team+unsubscribe@xxxxxxxxxxx. >