Re: Linux 5.10.12
From: Greg Kroah-Hartman
Date: Sat Jan 30 2021 - 09:26:05 EST
diff --git a/Makefile b/Makefile
index 7a5d906f6ee3..a6b2e64bcf6c 100644
--- a/Makefile
+++ b/Makefile
@@ -1,7 +1,7 @@
# SPDX-License-Identifier: GPL-2.0
VERSION = 5
PATCHLEVEL = 10
-SUBLEVEL = 11
+SUBLEVEL = 12
EXTRAVERSION =
NAME = Kleptomaniac Octopus
diff --git a/drivers/gpio/gpio-mvebu.c b/drivers/gpio/gpio-mvebu.c
index 2f245594a90a..ed7c5fc47f52 100644
--- a/drivers/gpio/gpio-mvebu.c
+++ b/drivers/gpio/gpio-mvebu.c
@@ -660,9 +660,8 @@ static void mvebu_pwm_get_state(struct pwm_chip *chip,
spin_lock_irqsave(&mvpwm->lock, flags);
- val = (unsigned long long)
- readl_relaxed(mvebu_pwmreg_blink_on_duration(mvpwm));
- val *= NSEC_PER_SEC;
+ u = readl_relaxed(mvebu_pwmreg_blink_on_duration(mvpwm));
+ val = (unsigned long long) u * NSEC_PER_SEC;
do_div(val, mvpwm->clk_rate);
if (val > UINT_MAX)
state->duty_cycle = UINT_MAX;
@@ -671,21 +670,17 @@ static void mvebu_pwm_get_state(struct pwm_chip *chip,
else
state->duty_cycle = 1;
- val = (unsigned long long)
- readl_relaxed(mvebu_pwmreg_blink_off_duration(mvpwm));
+ val = (unsigned long long) u; /* on duration */
+ /* period = on + off duration */
+ val += readl_relaxed(mvebu_pwmreg_blink_off_duration(mvpwm));
val *= NSEC_PER_SEC;
do_div(val, mvpwm->clk_rate);
- if (val < state->duty_cycle) {
+ if (val > UINT_MAX)
+ state->period = UINT_MAX;
+ else if (val)
+ state->period = val;
+ else
state->period = 1;
- } else {
- val -= state->duty_cycle;
- if (val > UINT_MAX)
- state->period = UINT_MAX;
- else if (val)
- state->period = val;
- else
- state->period = 1;
- }
regmap_read(mvchip->regs, GPIO_BLINK_EN_OFF + mvchip->offset, &u);
if (u)
diff --git a/drivers/hid/hid-multitouch.c b/drivers/hid/hid-multitouch.c
index 0743ef51d3b2..8429ebe7097e 100644
--- a/drivers/hid/hid-multitouch.c
+++ b/drivers/hid/hid-multitouch.c
@@ -758,7 +758,8 @@ static int mt_touch_input_mapping(struct hid_device *hdev, struct hid_input *hi,
MT_STORE_FIELD(inrange_state);
return 1;
case HID_DG_CONFIDENCE:
- if (cls->name == MT_CLS_WIN_8 &&
+ if ((cls->name == MT_CLS_WIN_8 ||
+ cls->name == MT_CLS_WIN_8_FORCE_MULTI_INPUT) &&
(field->application == HID_DG_TOUCHPAD ||
field->application == HID_DG_TOUCHSCREEN))
app->quirks |= MT_QUIRK_CONFIDENCE;
diff --git a/drivers/hid/wacom_sys.c b/drivers/hid/wacom_sys.c
index 9e852b4bbf92..73dafa60080f 100644
--- a/drivers/hid/wacom_sys.c
+++ b/drivers/hid/wacom_sys.c
@@ -147,9 +147,9 @@ static int wacom_wac_pen_serial_enforce(struct hid_device *hdev,
}
if (flush)
- wacom_wac_queue_flush(hdev, &wacom_wac->pen_fifo);
+ wacom_wac_queue_flush(hdev, wacom_wac->pen_fifo);
else if (insert)
- wacom_wac_queue_insert(hdev, &wacom_wac->pen_fifo,
+ wacom_wac_queue_insert(hdev, wacom_wac->pen_fifo,
raw_data, report_size);
return insert && !flush;
@@ -1280,7 +1280,7 @@ static void wacom_devm_kfifo_release(struct device *dev, void *res)
static int wacom_devm_kfifo_alloc(struct wacom *wacom)
{
struct wacom_wac *wacom_wac = &wacom->wacom_wac;
- struct kfifo_rec_ptr_2 *pen_fifo = &wacom_wac->pen_fifo;
+ struct kfifo_rec_ptr_2 *pen_fifo;
int error;
pen_fifo = devres_alloc(wacom_devm_kfifo_release,
@@ -1297,6 +1297,7 @@ static int wacom_devm_kfifo_alloc(struct wacom *wacom)
}
devres_add(&wacom->hdev->dev, pen_fifo);
+ wacom_wac->pen_fifo = pen_fifo;
return 0;
}
diff --git a/drivers/hid/wacom_wac.h b/drivers/hid/wacom_wac.h
index da612b6e9c77..195910dd2154 100644
--- a/drivers/hid/wacom_wac.h
+++ b/drivers/hid/wacom_wac.h
@@ -342,7 +342,7 @@ struct wacom_wac {
struct input_dev *pen_input;
struct input_dev *touch_input;
struct input_dev *pad_input;
- struct kfifo_rec_ptr_2 pen_fifo;
+ struct kfifo_rec_ptr_2 *pen_fifo;
int pid;
int num_contacts_left;
u8 bt_features;
diff --git a/drivers/infiniband/hw/vmw_pvrdma/pvrdma.h b/drivers/infiniband/hw/vmw_pvrdma/pvrdma.h
index c142f5e7f25f..de57f2fed743 100644
--- a/drivers/infiniband/hw/vmw_pvrdma/pvrdma.h
+++ b/drivers/infiniband/hw/vmw_pvrdma/pvrdma.h
@@ -509,6 +509,20 @@ static inline int ib_send_flags_to_pvrdma(int flags)
return flags & PVRDMA_MASK(PVRDMA_SEND_FLAGS_MAX);
}
+static inline int pvrdma_network_type_to_ib(enum pvrdma_network_type type)
+{
+ switch (type) {
+ case PVRDMA_NETWORK_ROCE_V1:
+ return RDMA_NETWORK_ROCE_V1;
+ case PVRDMA_NETWORK_IPV4:
+ return RDMA_NETWORK_IPV4;
+ case PVRDMA_NETWORK_IPV6:
+ return RDMA_NETWORK_IPV6;
+ default:
+ return RDMA_NETWORK_IPV6;
+ }
+}
+
void pvrdma_qp_cap_to_ib(struct ib_qp_cap *dst,
const struct pvrdma_qp_cap *src);
void ib_qp_cap_to_pvrdma(struct pvrdma_qp_cap *dst,
diff --git a/drivers/infiniband/hw/vmw_pvrdma/pvrdma_cq.c b/drivers/infiniband/hw/vmw_pvrdma/pvrdma_cq.c
index 319546a39a0d..62164db593a4 100644
--- a/drivers/infiniband/hw/vmw_pvrdma/pvrdma_cq.c
+++ b/drivers/infiniband/hw/vmw_pvrdma/pvrdma_cq.c
@@ -364,7 +364,7 @@ static int pvrdma_poll_one(struct pvrdma_cq *cq, struct pvrdma_qp **cur_qp,
wc->dlid_path_bits = cqe->dlid_path_bits;
wc->port_num = cqe->port_num;
wc->vendor_err = cqe->vendor_err;
- wc->network_hdr_type = cqe->network_hdr_type;
+ wc->network_hdr_type = pvrdma_network_type_to_ib(cqe->network_hdr_type);
/* Update shared ring state */
pvrdma_idx_ring_inc(&cq->ring_state->rx.cons_head, cq->ibcq.cqe);
diff --git a/drivers/media/common/videobuf2/videobuf2-v4l2.c b/drivers/media/common/videobuf2/videobuf2-v4l2.c
index 96d3b2b2aa31..3f61f5863bf7 100644
--- a/drivers/media/common/videobuf2/videobuf2-v4l2.c
+++ b/drivers/media/common/videobuf2/videobuf2-v4l2.c
@@ -118,8 +118,7 @@ static int __verify_length(struct vb2_buffer *vb, const struct v4l2_buffer *b)
return -EINVAL;
}
} else {
- length = (b->memory == VB2_MEMORY_USERPTR ||
- b->memory == VB2_MEMORY_DMABUF)
+ length = (b->memory == VB2_MEMORY_USERPTR)
? b->length : vb->planes[0].length;
if (b->bytesused > length)
diff --git a/drivers/net/wireless/intel/iwlwifi/iwl-dbg-tlv.c b/drivers/net/wireless/intel/iwlwifi/iwl-dbg-tlv.c
index 8fa1c22fd96d..fcad5cdcabfa 100644
--- a/drivers/net/wireless/intel/iwlwifi/iwl-dbg-tlv.c
+++ b/drivers/net/wireless/intel/iwlwifi/iwl-dbg-tlv.c
@@ -237,13 +237,6 @@ static int iwl_dbg_tlv_alloc_region(struct iwl_trans *trans,
if (le32_to_cpu(tlv->length) < sizeof(*reg))
return -EINVAL;
- /* For safe using a string from FW make sure we have a
- * null terminator
- */
- reg->name[IWL_FW_INI_MAX_NAME - 1] = 0;
-
- IWL_DEBUG_FW(trans, "WRT: parsing region: %s\n", reg->name);
-
if (id >= IWL_FW_INI_MAX_REGION_ID) {
IWL_ERR(trans, "WRT: Invalid region id %u\n", id);
return -EINVAL;
diff --git a/fs/file.c b/fs/file.c
index 4559b5fec3bd..21c0893f2f1d 100644
--- a/fs/file.c
+++ b/fs/file.c
@@ -21,7 +21,6 @@
#include <linux/rcupdate.h>
#include <linux/close_range.h>
#include <net/sock.h>
-#include <linux/io_uring.h>
unsigned int sysctl_nr_open __read_mostly = 1024*1024;
unsigned int sysctl_nr_open_min = BITS_PER_LONG;
@@ -453,7 +452,6 @@ void exit_files(struct task_struct *tsk)
struct files_struct * files = tsk->files;
if (files) {
- io_uring_files_cancel(files);
task_lock(tsk);
tsk->files = NULL;
task_unlock(tsk);
diff --git a/fs/io_uring.c b/fs/io_uring.c
index 8cb0db187d90..fd12d9327ee5 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -260,6 +260,7 @@ struct io_ring_ctx {
unsigned int drain_next: 1;
unsigned int eventfd_async: 1;
unsigned int restricted: 1;
+ unsigned int sqo_dead: 1;
/*
* Ring buffer of indices into array of io_uring_sqe, which is
@@ -970,6 +971,7 @@ static ssize_t io_import_iovec(int rw, struct io_kiocb *req,
static int io_setup_async_rw(struct io_kiocb *req, const struct iovec *iovec,
const struct iovec *fast_iov,
struct iov_iter *iter, bool force);
+static void io_req_drop_files(struct io_kiocb *req);
static struct kmem_cache *req_cachep;
@@ -990,8 +992,7 @@ EXPORT_SYMBOL(io_uring_get_socket);
static inline void io_clean_op(struct io_kiocb *req)
{
- if (req->flags & (REQ_F_NEED_CLEANUP | REQ_F_BUFFER_SELECTED |
- REQ_F_INFLIGHT))
+ if (req->flags & (REQ_F_NEED_CLEANUP | REQ_F_BUFFER_SELECTED))
__io_clean_op(req);
}
@@ -1213,11 +1214,6 @@ static void __io_commit_cqring(struct io_ring_ctx *ctx)
/* order cqe stores with ring update */
smp_store_release(&rings->cq.tail, ctx->cached_cq_tail);
-
- if (wq_has_sleeper(&ctx->cq_wait)) {
- wake_up_interruptible(&ctx->cq_wait);
- kill_fasync(&ctx->cq_fasync, SIGIO, POLL_IN);
- }
}
static void io_put_identity(struct io_uring_task *tctx, struct io_kiocb *req)
@@ -1260,6 +1256,8 @@ static void io_req_clean_work(struct io_kiocb *req)
free_fs_struct(fs);
req->work.flags &= ~IO_WQ_WORK_FS;
}
+ if (req->flags & REQ_F_INFLIGHT)
+ io_req_drop_files(req);
io_put_identity(req->task->io_uring, req);
}
@@ -1603,6 +1601,10 @@ static inline bool io_should_trigger_evfd(struct io_ring_ctx *ctx)
static void io_cqring_ev_posted(struct io_ring_ctx *ctx)
{
+ if (wq_has_sleeper(&ctx->cq_wait)) {
+ wake_up_interruptible(&ctx->cq_wait);
+ kill_fasync(&ctx->cq_fasync, SIGIO, POLL_IN);
+ }
if (waitqueue_active(&ctx->wait))
wake_up(&ctx->wait);
if (ctx->sq_data && waitqueue_active(&ctx->sq_data->wait))
@@ -2083,11 +2085,9 @@ static void io_req_task_cancel(struct callback_head *cb)
static void __io_req_task_submit(struct io_kiocb *req)
{
struct io_ring_ctx *ctx = req->ctx;
- bool fail;
- fail = __io_sq_thread_acquire_mm(ctx);
mutex_lock(&ctx->uring_lock);
- if (!fail)
+ if (!ctx->sqo_dead && !__io_sq_thread_acquire_mm(ctx))
__io_queue_sqe(req, NULL);
else
__io_req_task_cancel(req, -EFAULT);
@@ -5962,9 +5962,6 @@ static void __io_clean_op(struct io_kiocb *req)
}
req->flags &= ~REQ_F_NEED_CLEANUP;
}
-
- if (req->flags & REQ_F_INFLIGHT)
- io_req_drop_files(req);
}
static int io_issue_sqe(struct io_kiocb *req, bool force_nonblock,
@@ -6796,7 +6793,7 @@ static enum sq_ret __io_sq_thread(struct io_ring_ctx *ctx,
to_submit = 8;
mutex_lock(&ctx->uring_lock);
- if (likely(!percpu_ref_is_dying(&ctx->refs)))
+ if (likely(!percpu_ref_is_dying(&ctx->refs) && !ctx->sqo_dead))
ret = io_submit_sqes(ctx, to_submit);
mutex_unlock(&ctx->uring_lock);
@@ -8487,6 +8484,10 @@ static void io_ring_ctx_wait_and_kill(struct io_ring_ctx *ctx)
mutex_lock(&ctx->uring_lock);
percpu_ref_kill(&ctx->refs);
/* if force is set, the ring is going away. always drop after that */
+
+ if (WARN_ON_ONCE((ctx->flags & IORING_SETUP_SQPOLL) && !ctx->sqo_dead))
+ ctx->sqo_dead = 1;
+
ctx->cq_overflow_flushed = 1;
if (ctx->rings)
__io_cqring_overflow_flush(ctx, true, NULL, NULL);
@@ -8698,6 +8699,8 @@ static bool io_uring_cancel_files(struct io_ring_ctx *ctx,
break;
/* cancel this request, or head link requests */
io_attempt_cancel(ctx, cancel_req);
+ io_cqring_overflow_flush(ctx, true, task, files);
+
io_put_req(cancel_req);
/* cancellations _may_ trigger task work */
io_run_task_work();
@@ -8745,6 +8748,17 @@ static bool __io_uring_cancel_task_requests(struct io_ring_ctx *ctx,
return ret;
}
+static void io_disable_sqo_submit(struct io_ring_ctx *ctx)
+{
+ mutex_lock(&ctx->uring_lock);
+ ctx->sqo_dead = 1;
+ mutex_unlock(&ctx->uring_lock);
+
+ /* make sure callers enter the ring to get error */
+ if (ctx->rings)
+ io_ring_set_wakeup_flag(ctx);
+}
+
/*
* We need to iteratively cancel requests, in case a request has dependent
* hard links. These persist even for failure of cancelations, hence keep
@@ -8756,6 +8770,9 @@ static void io_uring_cancel_task_requests(struct io_ring_ctx *ctx,
struct task_struct *task = current;
if ((ctx->flags & IORING_SETUP_SQPOLL) && ctx->sq_data) {
+ /* for SQPOLL only sqo_task has task notes */
+ WARN_ON_ONCE(ctx->sqo_task != current);
+ io_disable_sqo_submit(ctx);
task = ctx->sq_data->thread;
atomic_inc(&task->io_uring->in_idle);
io_sq_thread_park(ctx->sq_data);
@@ -8835,23 +8852,6 @@ static void io_uring_del_task_file(struct file *file)
fput(file);
}
-/*
- * Drop task note for this file if we're the only ones that hold it after
- * pending fput()
- */
-static void io_uring_attempt_task_drop(struct file *file)
-{
- if (!current->io_uring)
- return;
- /*
- * fput() is pending, will be 2 if the only other ref is our potential
- * task file note. If the task is exiting, drop regardless of count.
- */
- if (fatal_signal_pending(current) || (current->flags & PF_EXITING) ||
- atomic_long_read(&file->f_count) == 2)
- io_uring_del_task_file(file);
-}
-
static void io_uring_remove_task_files(struct io_uring_task *tctx)
{
struct file *file;
@@ -8917,6 +8917,10 @@ void __io_uring_task_cancel(void)
/* make sure overflow events are dropped */
atomic_inc(&tctx->in_idle);
+ /* trigger io_disable_sqo_submit() */
+ if (tctx->sqpoll)
+ __io_uring_files_cancel(NULL);
+
do {
/* read completions before cancelations */
inflight = tctx_inflight(tctx);
@@ -8943,7 +8947,36 @@ void __io_uring_task_cancel(void)
static int io_uring_flush(struct file *file, void *data)
{
- io_uring_attempt_task_drop(file);
+ struct io_uring_task *tctx = current->io_uring;
+ struct io_ring_ctx *ctx = file->private_data;
+
+ if (!tctx)
+ return 0;
+
+ /* we should have cancelled and erased it before PF_EXITING */
+ WARN_ON_ONCE((current->flags & PF_EXITING) &&
+ xa_load(&tctx->xa, (unsigned long)file));
+
+ /*
+ * fput() is pending, will be 2 if the only other ref is our potential
+ * task file note. If the task is exiting, drop regardless of count.
+ */
+ if (atomic_long_read(&file->f_count) != 2)
+ return 0;
+
+ if (ctx->flags & IORING_SETUP_SQPOLL) {
+ /* there is only one file note, which is owned by sqo_task */
+ WARN_ON_ONCE(ctx->sqo_task != current &&
+ xa_load(&tctx->xa, (unsigned long)file));
+ /* sqo_dead check is for when this happens after cancellation */
+ WARN_ON_ONCE(ctx->sqo_task == current && !ctx->sqo_dead &&
+ !xa_load(&tctx->xa, (unsigned long)file));
+
+ io_disable_sqo_submit(ctx);
+ }
+
+ if (!(ctx->flags & IORING_SETUP_SQPOLL) || ctx->sqo_task == current)
+ io_uring_del_task_file(file);
return 0;
}
@@ -9017,8 +9050,9 @@ static unsigned long io_uring_nommu_get_unmapped_area(struct file *file,
#endif /* !CONFIG_MMU */
-static void io_sqpoll_wait_sq(struct io_ring_ctx *ctx)
+static int io_sqpoll_wait_sq(struct io_ring_ctx *ctx)
{
+ int ret = 0;
DEFINE_WAIT(wait);
do {
@@ -9027,6 +9061,11 @@ static void io_sqpoll_wait_sq(struct io_ring_ctx *ctx)
prepare_to_wait(&ctx->sqo_sq_wait, &wait, TASK_INTERRUPTIBLE);
+ if (unlikely(ctx->sqo_dead)) {
+ ret = -EOWNERDEAD;
+ goto out;
+ }
+
if (!io_sqring_full(ctx))
break;
@@ -9034,6 +9073,8 @@ static void io_sqpoll_wait_sq(struct io_ring_ctx *ctx)
} while (!signal_pending(current));
finish_wait(&ctx->sqo_sq_wait, &wait);
+out:
+ return ret;
}
SYSCALL_DEFINE6(io_uring_enter, unsigned int, fd, u32, to_submit,
@@ -9077,10 +9118,16 @@ SYSCALL_DEFINE6(io_uring_enter, unsigned int, fd, u32, to_submit,
if (ctx->flags & IORING_SETUP_SQPOLL) {
io_cqring_overflow_flush(ctx, false, NULL, NULL);
+ ret = -EOWNERDEAD;
+ if (unlikely(ctx->sqo_dead))
+ goto out;
if (flags & IORING_ENTER_SQ_WAKEUP)
wake_up(&ctx->sq_data->wait);
- if (flags & IORING_ENTER_SQ_WAIT)
- io_sqpoll_wait_sq(ctx);
+ if (flags & IORING_ENTER_SQ_WAIT) {
+ ret = io_sqpoll_wait_sq(ctx);
+ if (ret)
+ goto out;
+ }
submitted = to_submit;
} else if (to_submit) {
ret = io_uring_add_task_file(ctx, f.file);
@@ -9491,6 +9538,7 @@ static int io_uring_create(unsigned entries, struct io_uring_params *p,
*/
ret = io_uring_install_fd(ctx, file);
if (ret < 0) {
+ io_disable_sqo_submit(ctx);
/* fput will clean it up */
fput(file);
return ret;
@@ -9499,6 +9547,7 @@ static int io_uring_create(unsigned entries, struct io_uring_params *p,
trace_io_uring_create(ret, ctx, p->sq_entries, p->cq_entries, p->flags);
return ret;
err:
+ io_disable_sqo_submit(ctx);
io_ring_ctx_wait_and_kill(ctx);
return ret;
}
diff --git a/include/uapi/linux/v4l2-subdev.h b/include/uapi/linux/v4l2-subdev.h
index 00850b98078a..a38454d9e0f5 100644
--- a/include/uapi/linux/v4l2-subdev.h
+++ b/include/uapi/linux/v4l2-subdev.h
@@ -176,7 +176,7 @@ struct v4l2_subdev_capability {
};
/* The v4l2 sub-device video device node is registered in read-only mode. */
-#define V4L2_SUBDEV_CAP_RO_SUBDEV BIT(0)
+#define V4L2_SUBDEV_CAP_RO_SUBDEV 0x00000001
/* Backwards compatibility define --- to be removed */
#define v4l2_subdev_edid v4l2_edid
diff --git a/include/uapi/rdma/vmw_pvrdma-abi.h b/include/uapi/rdma/vmw_pvrdma-abi.h
index f8b638c73371..901a4fd72c09 100644
--- a/include/uapi/rdma/vmw_pvrdma-abi.h
+++ b/include/uapi/rdma/vmw_pvrdma-abi.h
@@ -133,6 +133,13 @@ enum pvrdma_wc_flags {
PVRDMA_WC_FLAGS_MAX = PVRDMA_WC_WITH_NETWORK_HDR_TYPE,
};
+enum pvrdma_network_type {
+ PVRDMA_NETWORK_IB,
+ PVRDMA_NETWORK_ROCE_V1 = PVRDMA_NETWORK_IB,
+ PVRDMA_NETWORK_IPV4,
+ PVRDMA_NETWORK_IPV6
+};
+
struct pvrdma_alloc_ucontext_resp {
__u32 qp_tab_size;
__u32 reserved;
diff --git a/kernel/exit.c b/kernel/exit.c
index 1f236ed375f8..d13d67fc5f4e 100644
--- a/kernel/exit.c
+++ b/kernel/exit.c
@@ -63,6 +63,7 @@
#include <linux/random.h>
#include <linux/rcuwait.h>
#include <linux/compat.h>
+#include <linux/io_uring.h>
#include <linux/uaccess.h>
#include <asm/unistd.h>
@@ -762,6 +763,7 @@ void __noreturn do_exit(long code)
schedule();
}
+ io_uring_files_cancel(tsk->files);
exit_signals(tsk); /* sets PF_EXITING */
/* sync mm's RSS info before statistics gathering */
diff --git a/kernel/futex.c b/kernel/futex.c
index 00259c7e288e..0693b3ea0f9a 100644
--- a/kernel/futex.c
+++ b/kernel/futex.c
@@ -765,6 +765,29 @@ static struct futex_pi_state *alloc_pi_state(void)
return pi_state;
}
+static void pi_state_update_owner(struct futex_pi_state *pi_state,
+ struct task_struct *new_owner)
+{
+ struct task_struct *old_owner = pi_state->owner;
+
+ lockdep_assert_held(&pi_state->pi_mutex.wait_lock);
+
+ if (old_owner) {
+ raw_spin_lock(&old_owner->pi_lock);
+ WARN_ON(list_empty(&pi_state->list));
+ list_del_init(&pi_state->list);
+ raw_spin_unlock(&old_owner->pi_lock);
+ }
+
+ if (new_owner) {
+ raw_spin_lock(&new_owner->pi_lock);
+ WARN_ON(!list_empty(&pi_state->list));
+ list_add(&pi_state->list, &new_owner->pi_state_list);
+ pi_state->owner = new_owner;
+ raw_spin_unlock(&new_owner->pi_lock);
+ }
+}
+
static void get_pi_state(struct futex_pi_state *pi_state)
{
WARN_ON_ONCE(!refcount_inc_not_zero(&pi_state->refcount));
@@ -787,17 +810,11 @@ static void put_pi_state(struct futex_pi_state *pi_state)
* and has cleaned up the pi_state already
*/
if (pi_state->owner) {
- struct task_struct *owner;
unsigned long flags;
raw_spin_lock_irqsave(&pi_state->pi_mutex.wait_lock, flags);
- owner = pi_state->owner;
- if (owner) {
- raw_spin_lock(&owner->pi_lock);
- list_del_init(&pi_state->list);
- raw_spin_unlock(&owner->pi_lock);
- }
- rt_mutex_proxy_unlock(&pi_state->pi_mutex, owner);
+ pi_state_update_owner(pi_state, NULL);
+ rt_mutex_proxy_unlock(&pi_state->pi_mutex);
raw_spin_unlock_irqrestore(&pi_state->pi_mutex.wait_lock, flags);
}
@@ -943,7 +960,8 @@ static inline void exit_pi_state_list(struct task_struct *curr) { }
* FUTEX_OWNER_DIED bit. See [4]
*
* [10] There is no transient state which leaves owner and user space
- * TID out of sync.
+ * TID out of sync. Except one error case where the kernel is denied
+ * write access to the user address, see fixup_pi_state_owner().
*
*
* Serialization and lifetime rules:
@@ -1523,26 +1541,15 @@ static int wake_futex_pi(u32 __user *uaddr, u32 uval, struct futex_pi_state *pi_
ret = -EINVAL;
}
- if (ret)
- goto out_unlock;
-
- /*
- * This is a point of no return; once we modify the uval there is no
- * going back and subsequent operations must not fail.
- */
-
- raw_spin_lock(&pi_state->owner->pi_lock);
- WARN_ON(list_empty(&pi_state->list));
- list_del_init(&pi_state->list);
- raw_spin_unlock(&pi_state->owner->pi_lock);
-
- raw_spin_lock(&new_owner->pi_lock);
- WARN_ON(!list_empty(&pi_state->list));
- list_add(&pi_state->list, &new_owner->pi_state_list);
- pi_state->owner = new_owner;
- raw_spin_unlock(&new_owner->pi_lock);
-
- postunlock = __rt_mutex_futex_unlock(&pi_state->pi_mutex, &wake_q);
+ if (!ret) {
+ /*
+ * This is a point of no return; once we modified the uval
+ * there is no going back and subsequent operations must
+ * not fail.
+ */
+ pi_state_update_owner(pi_state, new_owner);
+ postunlock = __rt_mutex_futex_unlock(&pi_state->pi_mutex, &wake_q);
+ }
out_unlock:
raw_spin_unlock_irq(&pi_state->pi_mutex.wait_lock);
@@ -2325,18 +2332,13 @@ static void unqueue_me_pi(struct futex_q *q)
spin_unlock(q->lock_ptr);
}
-static int fixup_pi_state_owner(u32 __user *uaddr, struct futex_q *q,
- struct task_struct *argowner)
+static int __fixup_pi_state_owner(u32 __user *uaddr, struct futex_q *q,
+ struct task_struct *argowner)
{
struct futex_pi_state *pi_state = q->pi_state;
- u32 uval, curval, newval;
struct task_struct *oldowner, *newowner;
- u32 newtid;
- int ret, err = 0;
-
- lockdep_assert_held(q->lock_ptr);
-
- raw_spin_lock_irq(&pi_state->pi_mutex.wait_lock);
+ u32 uval, curval, newval, newtid;
+ int err = 0;
oldowner = pi_state->owner;
@@ -2370,14 +2372,12 @@ static int fixup_pi_state_owner(u32 __user *uaddr, struct futex_q *q,
* We raced against a concurrent self; things are
* already fixed up. Nothing to do.
*/
- ret = 0;
- goto out_unlock;
+ return 0;
}
if (__rt_mutex_futex_trylock(&pi_state->pi_mutex)) {
- /* We got the lock after all, nothing to fix. */
- ret = 0;
- goto out_unlock;
+ /* We got the lock. pi_state is correct. Tell caller. */
+ return 1;
}
/*
@@ -2404,8 +2404,7 @@ static int fixup_pi_state_owner(u32 __user *uaddr, struct futex_q *q,
* We raced against a concurrent self; things are
* already fixed up. Nothing to do.
*/
- ret = 0;
- goto out_unlock;
+ return 1;
}
newowner = argowner;
}
@@ -2435,22 +2434,9 @@ static int fixup_pi_state_owner(u32 __user *uaddr, struct futex_q *q,
* We fixed up user space. Now we need to fix the pi_state
* itself.
*/
- if (pi_state->owner != NULL) {
- raw_spin_lock(&pi_state->owner->pi_lock);
- WARN_ON(list_empty(&pi_state->list));
- list_del_init(&pi_state->list);
- raw_spin_unlock(&pi_state->owner->pi_lock);
- }
+ pi_state_update_owner(pi_state, newowner);
- pi_state->owner = newowner;
-
- raw_spin_lock(&newowner->pi_lock);
- WARN_ON(!list_empty(&pi_state->list));
- list_add(&pi_state->list, &newowner->pi_state_list);
- raw_spin_unlock(&newowner->pi_lock);
- raw_spin_unlock_irq(&pi_state->pi_mutex.wait_lock);
-
- return 0;
+ return argowner == current;
/*
* In order to reschedule or handle a page fault, we need to drop the
@@ -2471,17 +2457,16 @@ static int fixup_pi_state_owner(u32 __user *uaddr, struct futex_q *q,
switch (err) {
case -EFAULT:
- ret = fault_in_user_writeable(uaddr);
+ err = fault_in_user_writeable(uaddr);
break;
case -EAGAIN:
cond_resched();
- ret = 0;
+ err = 0;
break;
default:
WARN_ON_ONCE(1);
- ret = err;
break;
}
@@ -2491,17 +2476,44 @@ static int fixup_pi_state_owner(u32 __user *uaddr, struct futex_q *q,
/*
* Check if someone else fixed it for us:
*/
- if (pi_state->owner != oldowner) {
- ret = 0;
- goto out_unlock;
- }
+ if (pi_state->owner != oldowner)
+ return argowner == current;
- if (ret)
- goto out_unlock;
+ /* Retry if err was -EAGAIN or the fault in succeeded */
+ if (!err)
+ goto retry;
- goto retry;
+ /*
+ * fault_in_user_writeable() failed so user state is immutable. At
+ * best we can make the kernel state consistent but user state will
+ * be most likely hosed and any subsequent unlock operation will be
+ * rejected due to PI futex rule [10].
+ *
+ * Ensure that the rtmutex owner is also the pi_state owner despite
+ * the user space value claiming something different. There is no
+ * point in unlocking the rtmutex if current is the owner as it
+ * would need to wait until the next waiter has taken the rtmutex
+ * to guarantee consistent state. Keep it simple. Userspace asked
+ * for this wreckaged state.
+ *
+ * The rtmutex has an owner - either current or some other
+ * task. See the EAGAIN loop above.
+ */
+ pi_state_update_owner(pi_state, rt_mutex_owner(&pi_state->pi_mutex));
-out_unlock:
+ return err;
+}
+
+static int fixup_pi_state_owner(u32 __user *uaddr, struct futex_q *q,
+ struct task_struct *argowner)
+{
+ struct futex_pi_state *pi_state = q->pi_state;
+ int ret;
+
+ lockdep_assert_held(q->lock_ptr);
+
+ raw_spin_lock_irq(&pi_state->pi_mutex.wait_lock);
+ ret = __fixup_pi_state_owner(uaddr, q, argowner);
raw_spin_unlock_irq(&pi_state->pi_mutex.wait_lock);
return ret;
}
@@ -2525,8 +2537,6 @@ static long futex_wait_restart(struct restart_block *restart);
*/
static int fixup_owner(u32 __user *uaddr, struct futex_q *q, int locked)
{
- int ret = 0;
-
if (locked) {
/*
* Got the lock. We might not be the anticipated owner if we
@@ -2537,8 +2547,8 @@ static int fixup_owner(u32 __user *uaddr, struct futex_q *q, int locked)
* stable state, anything else needs more attention.
*/
if (q->pi_state->owner != current)
- ret = fixup_pi_state_owner(uaddr, q, current);
- return ret ? ret : locked;
+ return fixup_pi_state_owner(uaddr, q, current);
+ return 1;
}
/*
@@ -2549,23 +2559,17 @@ static int fixup_owner(u32 __user *uaddr, struct futex_q *q, int locked)
* Another speculative read; pi_state->owner == current is unstable
* but needs our attention.
*/
- if (q->pi_state->owner == current) {
- ret = fixup_pi_state_owner(uaddr, q, NULL);
- return ret;
- }
+ if (q->pi_state->owner == current)
+ return fixup_pi_state_owner(uaddr, q, NULL);
/*
* Paranoia check. If we did not take the lock, then we should not be
- * the owner of the rt_mutex.
+ * the owner of the rt_mutex. Warn and establish consistent state.
*/
- if (rt_mutex_owner(&q->pi_state->pi_mutex) == current) {
- printk(KERN_ERR "fixup_owner: ret = %d pi-mutex: %p "
- "pi-state %p\n", ret,
- q->pi_state->pi_mutex.owner,
- q->pi_state->owner);
- }
+ if (WARN_ON_ONCE(rt_mutex_owner(&q->pi_state->pi_mutex) == current))
+ return fixup_pi_state_owner(uaddr, q, current);
- return ret;
+ return 0;
}
/**
@@ -2773,7 +2777,6 @@ static int futex_lock_pi(u32 __user *uaddr, unsigned int flags,
ktime_t *time, int trylock)
{
struct hrtimer_sleeper timeout, *to;
- struct futex_pi_state *pi_state = NULL;
struct task_struct *exiting = NULL;
struct rt_mutex_waiter rt_waiter;
struct futex_hash_bucket *hb;
@@ -2909,23 +2912,8 @@ static int futex_lock_pi(u32 __user *uaddr, unsigned int flags,
if (res)
ret = (res < 0) ? res : 0;
- /*
- * If fixup_owner() faulted and was unable to handle the fault, unlock
- * it and return the fault to userspace.
- */
- if (ret && (rt_mutex_owner(&q.pi_state->pi_mutex) == current)) {
- pi_state = q.pi_state;
- get_pi_state(pi_state);
- }
-
/* Unqueue and drop the lock */
unqueue_me_pi(&q);
-
- if (pi_state) {
- rt_mutex_futex_unlock(&pi_state->pi_mutex);
- put_pi_state(pi_state);
- }
-
goto out;
out_unlock_put_key:
@@ -3185,7 +3173,6 @@ static int futex_wait_requeue_pi(u32 __user *uaddr, unsigned int flags,
u32 __user *uaddr2)
{
struct hrtimer_sleeper timeout, *to;
- struct futex_pi_state *pi_state = NULL;
struct rt_mutex_waiter rt_waiter;
struct futex_hash_bucket *hb;
union futex_key key2 = FUTEX_KEY_INIT;
@@ -3263,16 +3250,17 @@ static int futex_wait_requeue_pi(u32 __user *uaddr, unsigned int flags,
if (q.pi_state && (q.pi_state->owner != current)) {
spin_lock(q.lock_ptr);
ret = fixup_pi_state_owner(uaddr2, &q, current);
- if (ret && rt_mutex_owner(&q.pi_state->pi_mutex) == current) {
- pi_state = q.pi_state;
- get_pi_state(pi_state);
- }
/*
* Drop the reference to the pi state which
* the requeue_pi() code acquired for us.
*/
put_pi_state(q.pi_state);
spin_unlock(q.lock_ptr);
+ /*
+ * Adjust the return value. It's either -EFAULT or
+ * success (1) but the caller expects 0 for success.
+ */
+ ret = ret < 0 ? ret : 0;
}
} else {
struct rt_mutex *pi_mutex;
@@ -3303,25 +3291,10 @@ static int futex_wait_requeue_pi(u32 __user *uaddr, unsigned int flags,
if (res)
ret = (res < 0) ? res : 0;
- /*
- * If fixup_pi_state_owner() faulted and was unable to handle
- * the fault, unlock the rt_mutex and return the fault to
- * userspace.
- */
- if (ret && rt_mutex_owner(&q.pi_state->pi_mutex) == current) {
- pi_state = q.pi_state;
- get_pi_state(pi_state);
- }
-
/* Unqueue and drop the lock. */
unqueue_me_pi(&q);
}
- if (pi_state) {
- rt_mutex_futex_unlock(&pi_state->pi_mutex);
- put_pi_state(pi_state);
- }
-
if (ret == -EINTR) {
/*
* We've already been requeued, but cannot restart by calling
diff --git a/kernel/locking/rtmutex.c b/kernel/locking/rtmutex.c
index cfdd5b93264d..2f8cd616d3b2 100644
--- a/kernel/locking/rtmutex.c
+++ b/kernel/locking/rtmutex.c
@@ -1716,8 +1716,7 @@ void rt_mutex_init_proxy_locked(struct rt_mutex *lock,
* possible because it belongs to the pi_state which is about to be freed
* and it is not longer visible to other tasks.
*/
-void rt_mutex_proxy_unlock(struct rt_mutex *lock,
- struct task_struct *proxy_owner)
+void rt_mutex_proxy_unlock(struct rt_mutex *lock)
{
debug_rt_mutex_proxy_unlock(lock);
rt_mutex_set_owner(lock, NULL);
diff --git a/kernel/locking/rtmutex_common.h b/kernel/locking/rtmutex_common.h
index d1d62f942be2..ca6fb489007b 100644
--- a/kernel/locking/rtmutex_common.h
+++ b/kernel/locking/rtmutex_common.h
@@ -133,8 +133,7 @@ enum rtmutex_chainwalk {
extern struct task_struct *rt_mutex_next_owner(struct rt_mutex *lock);
extern void rt_mutex_init_proxy_locked(struct rt_mutex *lock,
struct task_struct *proxy_owner);
-extern void rt_mutex_proxy_unlock(struct rt_mutex *lock,
- struct task_struct *proxy_owner);
+extern void rt_mutex_proxy_unlock(struct rt_mutex *lock);
extern void rt_mutex_init_waiter(struct rt_mutex_waiter *waiter);
extern int __rt_mutex_start_proxy_lock(struct rt_mutex *lock,
struct rt_mutex_waiter *waiter,
diff --git a/kernel/printk/printk.c b/kernel/printk/printk.c
index 801f8bc52b34..aafec8cb8637 100644
--- a/kernel/printk/printk.c
+++ b/kernel/printk/printk.c
@@ -1338,11 +1338,16 @@ static size_t info_print_prefix(const struct printk_info *info, bool syslog,
* done:
*
* - Add prefix for each line.
+ * - Drop truncated lines that no longer fit into the buffer.
* - Add the trailing newline that has been removed in vprintk_store().
- * - Drop truncated lines that do not longer fit into the buffer.
+ * - Add a string terminator.
+ *
+ * Since the produced string is always terminated, the maximum possible
+ * return value is @r->text_buf_size - 1;
*
* Return: The length of the updated/prepared text, including the added
- * prefixes and the newline. The dropped line(s) are not counted.
+ * prefixes and the newline. The terminator is not counted. The dropped
+ * line(s) are not counted.
*/
static size_t record_print_text(struct printk_record *r, bool syslog,
bool time)
@@ -1385,26 +1390,31 @@ static size_t record_print_text(struct printk_record *r, bool syslog,
/*
* Truncate the text if there is not enough space to add the
- * prefix and a trailing newline.
+ * prefix and a trailing newline and a terminator.
*/
- if (len + prefix_len + text_len + 1 > buf_size) {
+ if (len + prefix_len + text_len + 1 + 1 > buf_size) {
/* Drop even the current line if no space. */
- if (len + prefix_len + line_len + 1 > buf_size)
+ if (len + prefix_len + line_len + 1 + 1 > buf_size)
break;
- text_len = buf_size - len - prefix_len - 1;
+ text_len = buf_size - len - prefix_len - 1 - 1;
truncated = true;
}
memmove(text + prefix_len, text, text_len);
memcpy(text, prefix, prefix_len);
+ /*
+ * Increment the prepared length to include the text and
+ * prefix that were just moved+copied. Also increment for the
+ * newline at the end of this line. If this is the last line,
+ * there is no newline, but it will be added immediately below.
+ */
len += prefix_len + line_len + 1;
-
if (text_len == line_len) {
/*
- * Add the trailing newline removed in
- * vprintk_store().
+ * This is the last line. Add the trailing newline
+ * removed in vprintk_store().
*/
text[prefix_len + line_len] = '\n';
break;
@@ -1429,6 +1439,14 @@ static size_t record_print_text(struct printk_record *r, bool syslog,
text_len -= line_len + 1;
}
+ /*
+ * If a buffer was provided, it will be terminated. Space for the
+ * string terminator is guaranteed to be available. The terminator is
+ * not counted in the return value.
+ */
+ if (buf_size > 0)
+ r->text_buf[len] = 0;
+
return len;
}
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 14b9e83ff9da..88639706ae17 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -2846,20 +2846,20 @@ __rmqueue(struct zone *zone, unsigned int order, int migratetype,
{
struct page *page;
-#ifdef CONFIG_CMA
- /*
- * Balance movable allocations between regular and CMA areas by
- * allocating from CMA when over half of the zone's free memory
- * is in the CMA area.
- */
- if (alloc_flags & ALLOC_CMA &&
- zone_page_state(zone, NR_FREE_CMA_PAGES) >
- zone_page_state(zone, NR_FREE_PAGES) / 2) {
- page = __rmqueue_cma_fallback(zone, order);
- if (page)
- return page;
+ if (IS_ENABLED(CONFIG_CMA)) {
+ /*
+ * Balance movable allocations between regular and CMA areas by
+ * allocating from CMA when over half of the zone's free memory
+ * is in the CMA area.
+ */
+ if (alloc_flags & ALLOC_CMA &&
+ zone_page_state(zone, NR_FREE_CMA_PAGES) >
+ zone_page_state(zone, NR_FREE_PAGES) / 2) {
+ page = __rmqueue_cma_fallback(zone, order);
+ if (page)
+ goto out;
+ }
}
-#endif
retry:
page = __rmqueue_smallest(zone, order, migratetype);
if (unlikely(!page)) {
@@ -2870,8 +2870,9 @@ __rmqueue(struct zone *zone, unsigned int order, int migratetype,
alloc_flags))
goto retry;
}
-
- trace_mm_page_alloc_zone_locked(page, order, migratetype);
+out:
+ if (page)
+ trace_mm_page_alloc_zone_locked(page, order, migratetype);
return page;
}
diff --git a/mm/slub.c b/mm/slub.c
index 3f4303f4b657..071e41067ea6 100644
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -5620,10 +5620,8 @@ static int sysfs_slab_add(struct kmem_cache *s)
s->kobj.kset = kset;
err = kobject_init_and_add(&s->kobj, &slab_ktype, NULL, "%s", name);
- if (err) {
- kobject_put(&s->kobj);
+ if (err)
goto out;
- }
err = sysfs_create_group(&s->kobj, &slab_attr_group);
if (err)
diff --git a/mm/swapfile.c b/mm/swapfile.c
index d58361109066..16db9d1ebcbf 100644
--- a/mm/swapfile.c
+++ b/mm/swapfile.c
@@ -1045,16 +1045,18 @@ int get_swap_pages(int n_goal, swp_entry_t swp_entries[], int entry_size)
/* Only single cluster request supported */
WARN_ON_ONCE(n_goal > 1 && size == SWAPFILE_CLUSTER);
+ spin_lock(&swap_avail_lock);
+
avail_pgs = atomic_long_read(&nr_swap_pages) / size;
- if (avail_pgs <= 0)
+ if (avail_pgs <= 0) {
+ spin_unlock(&swap_avail_lock);
goto noswap;
+ }
n_goal = min3((long)n_goal, (long)SWAP_BATCH, avail_pgs);
atomic_long_sub(n_goal * size, &nr_swap_pages);
- spin_lock(&swap_avail_lock);
-
start_over:
node = numa_node_id();
plist_for_each_entry_safe(si, next, &swap_avail_heads[node], avail_lists[node]) {
@@ -1128,14 +1130,13 @@ swp_entry_t get_swap_page_of_type(int type)
spin_lock(&si->lock);
if (si->flags & SWP_WRITEOK) {
- atomic_long_dec(&nr_swap_pages);
/* This is called for allocating swap entry, not cache */
offset = scan_swap_map(si, 1);
if (offset) {
+ atomic_long_dec(&nr_swap_pages);
spin_unlock(&si->lock);
return swp_entry(type, offset);
}
- atomic_long_inc(&nr_swap_pages);
}
spin_unlock(&si->lock);
fail:
diff --git a/tools/bpf/resolve_btfids/Makefile b/tools/bpf/resolve_btfids/Makefile
index 66cb92136de4..bf656432ad73 100644
--- a/tools/bpf/resolve_btfids/Makefile
+++ b/tools/bpf/resolve_btfids/Makefile
@@ -18,15 +18,6 @@ else
endif
# always use the host compiler
-ifneq ($(LLVM),)
-HOSTAR ?= llvm-ar
-HOSTCC ?= clang
-HOSTLD ?= ld.lld
-else
-HOSTAR ?= ar
-HOSTCC ?= gcc
-HOSTLD ?= ld
-endif
AR = $(HOSTAR)
CC = $(HOSTCC)
LD = $(HOSTLD)
diff --git a/tools/build/Makefile b/tools/build/Makefile
index 722f1700d96a..bae48e6fa995 100644
--- a/tools/build/Makefile
+++ b/tools/build/Makefile
@@ -15,10 +15,6 @@ endef
$(call allow-override,CC,$(CROSS_COMPILE)gcc)
$(call allow-override,LD,$(CROSS_COMPILE)ld)
-HOSTCC ?= gcc
-HOSTLD ?= ld
-HOSTAR ?= ar
-
export HOSTCC HOSTLD HOSTAR
ifeq ($(V),1)
diff --git a/tools/objtool/Makefile b/tools/objtool/Makefile
index 4ea9a833dde7..5cdb19036d7f 100644
--- a/tools/objtool/Makefile
+++ b/tools/objtool/Makefile
@@ -3,15 +3,6 @@ include ../scripts/Makefile.include
include ../scripts/Makefile.arch
# always use the host compiler
-ifneq ($(LLVM),)
-HOSTAR ?= llvm-ar
-HOSTCC ?= clang
-HOSTLD ?= ld.lld
-else
-HOSTAR ?= ar
-HOSTCC ?= gcc
-HOSTLD ?= ld
-endif
AR = $(HOSTAR)
CC = $(HOSTCC)
LD = $(HOSTLD)
diff --git a/tools/objtool/elf.c b/tools/objtool/elf.c
index 4e1d7460574b..9452cfb01ef1 100644
--- a/tools/objtool/elf.c
+++ b/tools/objtool/elf.c
@@ -354,8 +354,11 @@ static int read_symbols(struct elf *elf)
symtab = find_section_by_name(elf, ".symtab");
if (!symtab) {
- WARN("missing symbol table");
- return -1;
+ /*
+ * A missing symbol table is actually possible if it's an empty
+ * .o file. This can happen for thunk_64.o.
+ */
+ return 0;
}
symtab_shndx = find_section_by_name(elf, ".symtab_shndx");
diff --git a/tools/perf/Makefile.perf b/tools/perf/Makefile.perf
index 7ce3f2e8b9c7..62f3deb1d3a8 100644
--- a/tools/perf/Makefile.perf
+++ b/tools/perf/Makefile.perf
@@ -175,10 +175,6 @@ endef
LD += $(EXTRA_LDFLAGS)
-HOSTCC ?= gcc
-HOSTLD ?= ld
-HOSTAR ?= ar
-
PKG_CONFIG = $(CROSS_COMPILE)pkg-config
LLVM_CONFIG ?= llvm-config
diff --git a/tools/power/acpi/Makefile.config b/tools/power/acpi/Makefile.config
index 54a2857c2510..331f6d30f472 100644
--- a/tools/power/acpi/Makefile.config
+++ b/tools/power/acpi/Makefile.config
@@ -54,7 +54,6 @@ INSTALL_SCRIPT = ${INSTALL_PROGRAM}
CROSS = #/usr/i386-linux-uclibc/usr/bin/i386-uclibc-
CROSS_COMPILE ?= $(CROSS)
LD = $(CC)
-HOSTCC = gcc
# check if compiler option is supported
cc-supports = ${shell if $(CC) ${1} -S -o /dev/null -x c /dev/null > /dev/null 2>&1; then echo "$(1)"; fi;}
diff --git a/tools/scripts/Makefile.include b/tools/scripts/Makefile.include
index a7974638561c..1358e89cdf7d 100644
--- a/tools/scripts/Makefile.include
+++ b/tools/scripts/Makefile.include
@@ -59,6 +59,16 @@ $(call allow-override,LD,$(CROSS_COMPILE)ld)
$(call allow-override,CXX,$(CROSS_COMPILE)g++)
$(call allow-override,STRIP,$(CROSS_COMPILE)strip)
+ifneq ($(LLVM),)
+HOSTAR ?= llvm-ar
+HOSTCC ?= clang
+HOSTLD ?= ld.lld
+else
+HOSTAR ?= ar
+HOSTCC ?= gcc
+HOSTLD ?= ld
+endif
+
ifeq ($(CC_NO_CLANG), 1)
EXTRA_WARNINGS += -Wstrict-aliasing=3
endif