[PATCH AUTOSEL 4.20 24/60] bpf/test_run: fix unkillable BPF_PROG_TEST_RUN

[PATCH AUTOSEL 4.20 24/60] bpf/test_run: fix unkillable BPF_PROG_TEST_RUN

[Sasha Levin]

From: Stanislav Fomichev <sdf@google.com>

[ Upstream commit df1a2cb7c74b3d3abc8d8c2d690f82c8ebc3490a ]

Syzbot found out that running BPF_PROG_TEST_RUN with repeat=0xffffffff
makes process unkillable. The problem is that when CONFIG_PREEMPT is
enabled, we never see need_resched() return true. This is due to the
fact that preempt_enable() (which we do in bpf_test_run_one on each
iteration) now handles resched if it's needed.

Let's disable preemption for the whole run, not per test. In this case
we can properly see whether resched is needed.
Let's also properly return -EINTR to the userspace in case of a signal
interrupt.

See recent discussion:
http://lore.kernel.org/netdev/CAH3MdRWHr4N8jei8jxDppXjmw-Nw=puNDLbu1dQOFQHxfU2onA@mail.gmail.com

I'll follow up with the same fix bpf_prog_test_run_flow_dissector in
bpf-next.

Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 net/bpf/test_run.c | 45 ++++++++++++++++++++++++---------------------
 1 file changed, 24 insertions(+), 21 deletions(-)

diff --git a/net/bpf/test_run.c b/net/bpf/test_run.c
index 25001913d03b..14a631817e12 100644
--- a/net/bpf/test_run.c
+++ b/net/bpf/test_run.c
@@ -13,27 +13,13 @@
 #include <net/sock.h>
 #include <net/tcp.h>
 
-static __always_inline u32 bpf_test_run_one(struct bpf_prog *prog, void *ctx,
-		struct bpf_cgroup_storage *storage[MAX_BPF_CGROUP_STORAGE_TYPE])
-{
-	u32 ret;
-
-	preempt_disable();
-	rcu_read_lock();
-	bpf_cgroup_storage_set(storage);
-	ret = BPF_PROG_RUN(prog, ctx);
-	rcu_read_unlock();
-	preempt_enable();
-
-	return ret;
-}
-
-static int bpf_test_run(struct bpf_prog *prog, void *ctx, u32 repeat, u32 *ret,
-			u32 *time)
+static int bpf_test_run(struct bpf_prog *prog, void *ctx, u32 repeat,
+			u32 *retval, u32 *time)
 {
 	struct bpf_cgroup_storage *storage[MAX_BPF_CGROUP_STORAGE_TYPE] = { 0 };
 	enum bpf_cgroup_storage_type stype;
 	u64 time_start, time_spent = 0;
+	int ret = 0;
 	u32 i;
 
 	for_each_cgroup_storage_type(stype) {
@@ -48,25 +34,42 @@ static int bpf_test_run(struct bpf_prog *prog, void *ctx, u32 repeat, u32 *ret,
 
 	if (!repeat)
 		repeat = 1;
+
+	rcu_read_lock();
+	preempt_disable();
 	time_start = ktime_get_ns();
 	for (i = 0; i < repeat; i++) {
-		*ret = bpf_test_run_one(prog, ctx, storage);
+		bpf_cgroup_storage_set(storage);
+		*retval = BPF_PROG_RUN(prog, ctx);
+
+		if (signal_pending(current)) {
+			ret = -EINTR;
+			break;
+		}
+
 		if (need_resched()) {
-			if (signal_pending(current))
-				break;
 			time_spent += ktime_get_ns() - time_start;
+			preempt_enable();
+			rcu_read_unlock();
+
 			cond_resched();
+
+			rcu_read_lock();
+			preempt_disable();
 			time_start = ktime_get_ns();
 		}
 	}
 	time_spent += ktime_get_ns() - time_start;
+	preempt_enable();
+	rcu_read_unlock();
+
 	do_div(time_spent, repeat);
 	*time = time_spent > U32_MAX ? U32_MAX : (u32)time_spent;
 
 	for_each_cgroup_storage_type(stype)
 		bpf_cgroup_storage_free(storage[stype]);
 
-	return 0;
+	return ret;
 }
 
 static int bpf_test_finish(const union bpf_attr *kattr,
-- 
2.19.1

[PATCH AUTOSEL 4.20 41/60] i40e: fix potential RX buffer starvation for AF_XDP

[Sasha Levin]

From: Magnus Karlsson <magnus.karlsson@intel.com>

[ Upstream commit 14ffeb52f3693ae0b674e59453452a2365ae9fd9 ]

When the RX rings are created they are also populated with buffers
so that packets can be received. Usually these are kernel buffers,
but for AF_XDP in zero-copy mode, these are user-space buffers and
in this case the application might not have sent down any buffers
to the driver at this point. And if no buffers are allocated at ring
creation time, no packets can be received and no interrupts will be
generated so the NAPI poll function that allocates buffers to the
rings will never get executed.

To rectify this, we kick the NAPI context of any queue with an
attached AF_XDP zero-copy socket in two places in the code. Once
after an XDP program has loaded and once after the umem is registered.
This take care of both cases: XDP program gets loaded first then AF_XDP
socket is created, and the reverse, AF_XDP socket is created first,
then XDP program is loaded.

Fixes: 0a714186d3c0 ("i40e: add AF_XDP zero-copy Rx support")
Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/net/ethernet/intel/i40e/i40e_main.c | 13 ++++++++++++-
 drivers/net/ethernet/intel/i40e/i40e_xsk.c  |  5 +++++
 2 files changed, 17 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/intel/i40e/i40e_main.c b/drivers/net/ethernet/intel/i40e/i40e_main.c
index f97c3d5ab884..89a072b5ce6c 100644
--- a/drivers/net/ethernet/intel/i40e/i40e_main.c
+++ b/drivers/net/ethernet/intel/i40e/i40e_main.c
@@ -3290,8 +3290,11 @@ static int i40e_configure_rx_ring(struct i40e_ring *ring)
 	     i40e_alloc_rx_buffers_zc(ring, I40E_DESC_UNUSED(ring)) :
 	     !i40e_alloc_rx_buffers(ring, I40E_DESC_UNUSED(ring));
 	if (!ok) {
+		/* Log this in case the user has forgotten to give the kernel
+		 * any buffers, even later in the application.
+		 */
 		dev_info(&vsi->back->pdev->dev,
-			 "Failed allocate some buffers on %sRx ring %d (pf_q %d)\n",
+			 "Failed to allocate some buffers on %sRx ring %d (pf_q %d)\n",
 			 ring->xsk_umem ? "UMEM enabled " : "",
 			 ring->queue_index, pf_q);
 	}
@@ -11895,6 +11898,14 @@ static int i40e_xdp_setup(struct i40e_vsi *vsi,
 	if (old_prog)
 		bpf_prog_put(old_prog);
 
+	/* Kick start the NAPI context if there is an AF_XDP socket open
+	 * on that queue id. This so that receiving will start.
+	 */
+	if (need_reset && prog)
+		for (i = 0; i < vsi->num_queue_pairs; i++)
+			if (vsi->xdp_rings[i]->xsk_umem)
+				(void)i40e_xsk_async_xmit(vsi->netdev, i);
+
 	return 0;
 }
 
diff --git a/drivers/net/ethernet/intel/i40e/i40e_xsk.c b/drivers/net/ethernet/intel/i40e/i40e_xsk.c
index 870cf654e436..3827f16e6923 100644
--- a/drivers/net/ethernet/intel/i40e/i40e_xsk.c
+++ b/drivers/net/ethernet/intel/i40e/i40e_xsk.c
@@ -183,6 +183,11 @@ static int i40e_xsk_umem_enable(struct i40e_vsi *vsi, struct xdp_umem *umem,
 		err = i40e_queue_pair_enable(vsi, qid);
 		if (err)
 			return err;
+
+		/* Kick start the NAPI context so that receiving will start */
+		err = i40e_xsk_async_xmit(vsi->netdev, qid);
+		if (err)
+			return err;
 	}
 
 	return 0;
-- 
2.19.1

[PATCH AUTOSEL 4.20 42/60] ixgbe: fix potential RX buffer starvation for AF_XDP

[Sasha Levin]

From: Magnus Karlsson <magnus.karlsson@intel.com>

[ Upstream commit 4a9b32f30f805ca596d76605903a48eab58e0b88 ]

When the RX rings are created they are also populated with buffers so
that packets can be received. Usually these are kernel buffers, but
for AF_XDP in zero-copy mode, these are user-space buffers and in this
case the application might not have sent down any buffers to the
driver at this point. And if no buffers are allocated at ring creation
time, no packets can be received and no interrupts will be generated so
the NAPI poll function that allocates buffers to the rings will never
get executed.

To rectify this, we kick the NAPI context of any queue with an
attached AF_XDP zero-copy socket in two places in the code. Once after
an XDP program has loaded and once after the umem is registered.  This
take care of both cases: XDP program gets loaded first then AF_XDP
socket is created, and the reverse, AF_XDP socket is created first,
then XDP program is loaded.

Fixes: d0bcacd0a130 ("ixgbe: add AF_XDP zero-copy Rx support")
Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/net/ethernet/intel/ixgbe/ixgbe_main.c | 12 +++++++++++-
 drivers/net/ethernet/intel/ixgbe/ixgbe_xsk.c  | 12 ++++++++++--
 2 files changed, 21 insertions(+), 3 deletions(-)

diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
index aed1890514d6..8c47451f17f1 100644
--- a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
+++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
@@ -10207,6 +10207,7 @@ static int ixgbe_xdp_setup(struct net_device *dev, struct bpf_prog *prog)
 	int i, frame_size = dev->mtu + ETH_HLEN + ETH_FCS_LEN + VLAN_HLEN;
 	struct ixgbe_adapter *adapter = netdev_priv(dev);
 	struct bpf_prog *old_prog;
+	bool need_reset;
 
 	if (adapter->flags & IXGBE_FLAG_SRIOV_ENABLED)
 		return -EINVAL;
@@ -10229,9 +10230,10 @@ static int ixgbe_xdp_setup(struct net_device *dev, struct bpf_prog *prog)
 		return -ENOMEM;
 
 	old_prog = xchg(&adapter->xdp_prog, prog);
+	need_reset = (!!prog != !!old_prog);
 
 	/* If transitioning XDP modes reconfigure rings */
-	if (!!prog != !!old_prog) {
+	if (need_reset) {
 		int err = ixgbe_setup_tc(dev, adapter->hw_tcs);
 
 		if (err) {
@@ -10247,6 +10249,14 @@ static int ixgbe_xdp_setup(struct net_device *dev, struct bpf_prog *prog)
 	if (old_prog)
 		bpf_prog_put(old_prog);
 
+	/* Kick start the NAPI context if there is an AF_XDP socket open
+	 * on that queue id. This so that receiving will start.
+	 */
+	if (need_reset && prog)
+		for (i = 0; i < adapter->num_rx_queues; i++)
+			if (adapter->xdp_ring[i]->xsk_umem)
+				(void)ixgbe_xsk_async_xmit(adapter->netdev, i);
+
 	return 0;
 }
 
diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_xsk.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_xsk.c
index 65c3e2c979d4..654ae92342ea 100644
--- a/drivers/net/ethernet/intel/ixgbe/ixgbe_xsk.c
+++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_xsk.c
@@ -144,11 +144,19 @@ static int ixgbe_xsk_umem_enable(struct ixgbe_adapter *adapter,
 		ixgbe_txrx_ring_disable(adapter, qid);
 
 	err = ixgbe_add_xsk_umem(adapter, umem, qid);
+	if (err)
+		return err;
 
-	if (if_running)
+	if (if_running) {
 		ixgbe_txrx_ring_enable(adapter, qid);
 
-	return err;
+		/* Kick start the NAPI context so that receiving will start */
+		err = ixgbe_xsk_async_xmit(adapter->netdev, qid);
+		if (err)
+			return err;
+	}
+
+	return 0;
 }
 
 static int ixgbe_xsk_umem_disable(struct ixgbe_adapter *adapter, u16 qid)
-- 
2.19.1

[PATCH AUTOSEL 4.20 46/60] i40e: fix XDP_REDIRECT/XDP xmit ring cleanup race

[Sasha Levin]

From: Björn Töpel <bjorn.topel@intel.com>

[ Upstream commit 59eb2a884f5380011179acc4662fc2cc2d850454 ]

When the driver clears the XDP xmit ring due to re-configuration or
teardown, in-progress ndo_xdp_xmit must be taken into consideration.

The ndo_xdp_xmit function is typically called from a NAPI context that
the driver does not control. Therefore, we must be careful not to
clear the XDP ring, while the call is on-going. This patch adds a
synchronize_rcu() to wait for napi(s) (preempt-disable regions and
softirqs), prior clearing the queue. Further, the __I40E_CONFIG_BUSY
flag is checked in the ndo_xdp_xmit implementation to avoid touching
the XDP xmit queue during re-configuration.

Fixes: d9314c474d4f ("i40e: add support for XDP_REDIRECT")
Fixes: 123cecd427b6 ("i40e: added queue pair disable/enable functions")
Reported-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/net/ethernet/intel/i40e/i40e_main.c | 14 ++++++++++++--
 drivers/net/ethernet/intel/i40e/i40e_txrx.c |  4 +++-
 2 files changed, 15 insertions(+), 3 deletions(-)

diff --git a/drivers/net/ethernet/intel/i40e/i40e_main.c b/drivers/net/ethernet/intel/i40e/i40e_main.c
index 89a072b5ce6c..393647153857 100644
--- a/drivers/net/ethernet/intel/i40e/i40e_main.c
+++ b/drivers/net/ethernet/intel/i40e/i40e_main.c
@@ -6729,8 +6729,13 @@ void i40e_down(struct i40e_vsi *vsi)
 
 	for (i = 0; i < vsi->num_queue_pairs; i++) {
 		i40e_clean_tx_ring(vsi->tx_rings[i]);
-		if (i40e_enabled_xdp_vsi(vsi))
+		if (i40e_enabled_xdp_vsi(vsi)) {
+			/* Make sure that in-progress ndo_xdp_xmit
+			 * calls are completed.
+			 */
+			synchronize_rcu();
 			i40e_clean_tx_ring(vsi->xdp_rings[i]);
+		}
 		i40e_clean_rx_ring(vsi->rx_rings[i]);
 	}
 
@@ -11966,8 +11971,13 @@ static void i40e_queue_pair_reset_stats(struct i40e_vsi *vsi, int queue_pair)
 static void i40e_queue_pair_clean_rings(struct i40e_vsi *vsi, int queue_pair)
 {
 	i40e_clean_tx_ring(vsi->tx_rings[queue_pair]);
-	if (i40e_enabled_xdp_vsi(vsi))
+	if (i40e_enabled_xdp_vsi(vsi)) {
+		/* Make sure that in-progress ndo_xdp_xmit calls are
+		 * completed.
+		 */
+		synchronize_rcu();
 		i40e_clean_tx_ring(vsi->xdp_rings[queue_pair]);
+	}
 	i40e_clean_rx_ring(vsi->rx_rings[queue_pair]);
 }
 
diff --git a/drivers/net/ethernet/intel/i40e/i40e_txrx.c b/drivers/net/ethernet/intel/i40e/i40e_txrx.c
index d0a95424ce58..48a0d8a53895 100644
--- a/drivers/net/ethernet/intel/i40e/i40e_txrx.c
+++ b/drivers/net/ethernet/intel/i40e/i40e_txrx.c
@@ -3708,6 +3708,7 @@ int i40e_xdp_xmit(struct net_device *dev, int n, struct xdp_frame **frames,
 	struct i40e_netdev_priv *np = netdev_priv(dev);
 	unsigned int queue_index = smp_processor_id();
 	struct i40e_vsi *vsi = np->vsi;
+	struct i40e_pf *pf = vsi->back;
 	struct i40e_ring *xdp_ring;
 	int drops = 0;
 	int i;
@@ -3715,7 +3716,8 @@ int i40e_xdp_xmit(struct net_device *dev, int n, struct xdp_frame **frames,
 	if (test_bit(__I40E_VSI_DOWN, vsi->state))
 		return -ENETDOWN;
 
-	if (!i40e_enabled_xdp_vsi(vsi) || queue_index >= vsi->num_queue_pairs)
+	if (!i40e_enabled_xdp_vsi(vsi) || queue_index >= vsi->num_queue_pairs ||
+	    test_bit(__I40E_CONFIG_BUSY, pf->state))
 		return -ENXIO;
 
 	if (unlikely(flags & ~XDP_XMIT_FLAGS_MASK))
-- 
2.19.1

[PATCH AUTOSEL 4.20 47/60] ixgbe: don't do any AF_XDP zero-copy transmit if netif is not OK

[Sasha Levin]

From: Jan Sokolowski <jan.sokolowski@intel.com>

[ Upstream commit c685c69fba71462c3f9f6a1fb6151cded6c74d42 ]

An issue has been found while testing zero-copy XDP that
causes a reset to be triggered. As it takes some time to
turn the carrier on after setting zc, and we already
start trying to transmit some packets, watchdog considers
this as an erroneous state and triggers a reset.

Don't do any work if netif carrier is not OK.

Fixes: 8221c5eba8c13 (ixgbe: add AF_XDP zero-copy Tx support)
Signed-off-by: Jan Sokolowski <jan.sokolowski@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/net/ethernet/intel/ixgbe/ixgbe_xsk.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_xsk.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_xsk.c
index 654ae92342ea..36a8879536a4 100644
--- a/drivers/net/ethernet/intel/ixgbe/ixgbe_xsk.c
+++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_xsk.c
@@ -642,7 +642,8 @@ static bool ixgbe_xmit_zc(struct ixgbe_ring *xdp_ring, unsigned int budget)
 	dma_addr_t dma;
 
 	while (budget-- > 0) {
-		if (unlikely(!ixgbe_desc_unused(xdp_ring))) {
+		if (unlikely(!ixgbe_desc_unused(xdp_ring)) ||
+		    !netif_carrier_ok(xdp_ring->netdev)) {
 			work_done = false;
 			break;
 		}
-- 
2.19.1

[PATCH AUTOSEL 4.20 51/60] bpf, lpm: fix lookup bug in map_delete_elem

[Sasha Levin]

From: Alban Crequy <alban@kinvolk.io>

[ Upstream commit 7c0cdf0b3940f63d9777c3fcf250a2f83859ca54 ]

trie_delete_elem() was deleting an entry even though it was not matching
if the prefixlen was correct. This patch adds a check on matchlen.

Reproducer:

$ sudo bpftool map create /sys/fs/bpf/mylpm type lpm_trie key 8 value 1 entries 128 name mylpm flags 1
$ sudo bpftool map update pinned /sys/fs/bpf/mylpm key hex 10 00 00 00 aa bb cc dd value hex 01
$ sudo bpftool map dump pinned /sys/fs/bpf/mylpm
key: 10 00 00 00 aa bb cc dd  value: 01
Found 1 element
$ sudo bpftool map delete pinned /sys/fs/bpf/mylpm key hex 10 00 00 00 ff ff ff ff
$ echo $?
0
$ sudo bpftool map dump pinned /sys/fs/bpf/mylpm
Found 0 elements

A similar reproducer is added in the selftests.

Without the patch:

$ sudo ./tools/testing/selftests/bpf/test_lpm_map
test_lpm_map: test_lpm_map.c:485: test_lpm_delete: Assertion `bpf_map_delete_elem(map_fd, key) == -1 && errno == ENOENT' failed.
Aborted

With the patch: test_lpm_map runs without errors.

Fixes: e454cf595853 ("bpf: Implement map_delete_elem for BPF_MAP_TYPE_LPM_TRIE")
Cc: Craig Gallek <kraig@google.com>
Signed-off-by: Alban Crequy <alban@kinvolk.io>
Acked-by: Craig Gallek <kraig@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 kernel/bpf/lpm_trie.c                      |  1 +
 tools/testing/selftests/bpf/test_lpm_map.c | 10 ++++++++++
 2 files changed, 11 insertions(+)

diff --git a/kernel/bpf/lpm_trie.c b/kernel/bpf/lpm_trie.c
index 9058317ba9de..4f3138e6ecb2 100644
--- a/kernel/bpf/lpm_trie.c
+++ b/kernel/bpf/lpm_trie.c
@@ -432,6 +432,7 @@ static int trie_delete_elem(struct bpf_map *map, void *_key)
 	}
 
 	if (!node || node->prefixlen != key->prefixlen ||
+	    node->prefixlen != matchlen ||
 	    (node->flags & LPM_TREE_NODE_FLAG_IM)) {
 		ret = -ENOENT;
 		goto out;
diff --git a/tools/testing/selftests/bpf/test_lpm_map.c b/tools/testing/selftests/bpf/test_lpm_map.c
index 147e34cfceb7..02d7c871862a 100644
--- a/tools/testing/selftests/bpf/test_lpm_map.c
+++ b/tools/testing/selftests/bpf/test_lpm_map.c
@@ -474,6 +474,16 @@ static void test_lpm_delete(void)
 	assert(bpf_map_lookup_elem(map_fd, key, &value) == -1 &&
 		errno == ENOENT);
 
+	key->prefixlen = 30; // unused prefix so far
+	inet_pton(AF_INET, "192.255.0.0", key->data);
+	assert(bpf_map_delete_elem(map_fd, key) == -1 &&
+		errno == ENOENT);
+
+	key->prefixlen = 16; // same prefix as the root node
+	inet_pton(AF_INET, "192.255.0.0", key->data);
+	assert(bpf_map_delete_elem(map_fd, key) == -1 &&
+		errno == ENOENT);
+
 	/* assert initial lookup */
 	key->prefixlen = 32;
 	inet_pton(AF_INET, "192.168.0.1", key->data);
-- 
2.19.1

[PATCH AUTOSEL 4.20 54/60] nfp: bpf: fix code-gen bug on BPF_ALU | BPF_XOR | BPF_K

[Sasha Levin]

From: Jiong Wang <jiong.wang@netronome.com>

[ Upstream commit 71c190249f0ced5b26377ea6bf829ab3af77a40c ]

The intended optimization should be A ^ 0 = A, not A ^ -1 = A.

Fixes: cd7df56ed3e6 ("nfp: add BPF to NFP code translator")
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Jiong Wang <jiong.wang@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/net/ethernet/netronome/nfp/bpf/jit.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/netronome/nfp/bpf/jit.c b/drivers/net/ethernet/netronome/nfp/bpf/jit.c
index 97d33bb4d84d..0762401ee3fe 100644
--- a/drivers/net/ethernet/netronome/nfp/bpf/jit.c
+++ b/drivers/net/ethernet/netronome/nfp/bpf/jit.c
@@ -2309,7 +2309,7 @@ static int xor_reg(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
 
 static int xor_imm(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
 {
-	return wrp_alu32_imm(nfp_prog, meta, ALU_OP_XOR, !~meta->insn.imm);
+	return wrp_alu32_imm(nfp_prog, meta, ALU_OP_XOR, !meta->insn.imm);
 }
 
 static int and_reg(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
-- 
2.19.1

[PATCH AUTOSEL 4.20 55/60] nfp: bpf: fix ALU32 high bits clearance bug

[Sasha Levin]

From: Jiong Wang <jiong.wang@netronome.com>

[ Upstream commit f036ebd9bfbe1e91a3d855e85e05fc5ff156b641 ]

NFP BPF JIT compiler is doing a couple of small optimizations when jitting
ALU imm instructions, some of these optimizations could save code-gen, for
example:

  A & -1 =  A
  A |  0 =  A
  A ^  0 =  A

However, for ALU32, high 32-bit of the 64-bit register should still be
cleared according to ISA semantics.

Fixes: cd7df56ed3e6 ("nfp: add BPF to NFP code translator")
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Jiong Wang <jiong.wang@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/net/ethernet/netronome/nfp/bpf/jit.c | 17 ++++++-----------
 1 file changed, 6 insertions(+), 11 deletions(-)

diff --git a/drivers/net/ethernet/netronome/nfp/bpf/jit.c b/drivers/net/ethernet/netronome/nfp/bpf/jit.c
index 0762401ee3fe..c89381bad6e4 100644
--- a/drivers/net/ethernet/netronome/nfp/bpf/jit.c
+++ b/drivers/net/ethernet/netronome/nfp/bpf/jit.c
@@ -1291,15 +1291,10 @@ wrp_alu64_reg(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta,
 
 static int
 wrp_alu32_imm(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta,
-	      enum alu_op alu_op, bool skip)
+	      enum alu_op alu_op)
 {
 	const struct bpf_insn *insn = &meta->insn;
 
-	if (skip) {
-		meta->skip = true;
-		return 0;
-	}
-
 	wrp_alu_imm(nfp_prog, insn->dst_reg * 2, alu_op, insn->imm);
 	wrp_immed(nfp_prog, reg_both(insn->dst_reg * 2 + 1), 0);
 
@@ -2309,7 +2304,7 @@ static int xor_reg(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
 
 static int xor_imm(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
 {
-	return wrp_alu32_imm(nfp_prog, meta, ALU_OP_XOR, !meta->insn.imm);
+	return wrp_alu32_imm(nfp_prog, meta, ALU_OP_XOR);
 }
 
 static int and_reg(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
@@ -2319,7 +2314,7 @@ static int and_reg(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
 
 static int and_imm(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
 {
-	return wrp_alu32_imm(nfp_prog, meta, ALU_OP_AND, !~meta->insn.imm);
+	return wrp_alu32_imm(nfp_prog, meta, ALU_OP_AND);
 }
 
 static int or_reg(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
@@ -2329,7 +2324,7 @@ static int or_reg(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
 
 static int or_imm(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
 {
-	return wrp_alu32_imm(nfp_prog, meta, ALU_OP_OR, !meta->insn.imm);
+	return wrp_alu32_imm(nfp_prog, meta, ALU_OP_OR);
 }
 
 static int add_reg(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
@@ -2339,7 +2334,7 @@ static int add_reg(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
 
 static int add_imm(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
 {
-	return wrp_alu32_imm(nfp_prog, meta, ALU_OP_ADD, !meta->insn.imm);
+	return wrp_alu32_imm(nfp_prog, meta, ALU_OP_ADD);
 }
 
 static int sub_reg(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
@@ -2349,7 +2344,7 @@ static int sub_reg(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
 
 static int sub_imm(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
 {
-	return wrp_alu32_imm(nfp_prog, meta, ALU_OP_SUB, !meta->insn.imm);
+	return wrp_alu32_imm(nfp_prog, meta, ALU_OP_SUB);
 }
 
 static int mul_reg(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
-- 
2.19.1