[PATCH AUTOSEL 5.2 39/85] selftests/bpf: do not ignore clang failures

[PATCH AUTOSEL 5.2 39/85] selftests/bpf: do not ignore clang failures

[Sasha Levin]

From: Ilya Leoshkevich <iii@linux.ibm.com>

[ Upstream commit 9cae4ace80ef39005da106fbb89c952b27d7b89e ]

When compiling an eBPF prog fails, make still returns 0, because
failing clang command's output is piped to llc and therefore its
exit status is ignored.

When clang fails, pipe the string "clang failed" to llc. This will make
llc fail with an informative error message. This solution was chosen
over using pipefail, having separate targets or getting rid of llc
invocation due to its simplicity.

In addition, pull Kbuild.include in order to get .DELETE_ON_ERROR target,
which would cause partial .o files to be removed.

Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 tools/testing/selftests/bpf/Makefile | 13 +++++++------
 1 file changed, 7 insertions(+), 6 deletions(-)

diff --git a/tools/testing/selftests/bpf/Makefile b/tools/testing/selftests/bpf/Makefile
index e36356e2377e..e375f399b7a6 100644
--- a/tools/testing/selftests/bpf/Makefile
+++ b/tools/testing/selftests/bpf/Makefile
@@ -1,4 +1,5 @@
 # SPDX-License-Identifier: GPL-2.0
+include ../../../../scripts/Kbuild.include
 
 LIBDIR := ../../../lib
 BPFDIR := $(LIBDIR)/bpf
@@ -185,8 +186,8 @@ $(ALU32_BUILD_DIR)/test_progs_32: prog_tests/*.c
 
 $(ALU32_BUILD_DIR)/%.o: progs/%.c $(ALU32_BUILD_DIR) \
 					$(ALU32_BUILD_DIR)/test_progs_32
-	$(CLANG) $(CLANG_FLAGS) \
-		 -O2 -target bpf -emit-llvm -c $< -o - |      \
+	($(CLANG) $(CLANG_FLAGS) -O2 -target bpf -emit-llvm -c $< -o - || \
+		echo "clang failed") | \
 	$(LLC) -march=bpf -mattr=+alu32 -mcpu=$(CPU) $(LLC_FLAGS) \
 		-filetype=obj -o $@
 ifeq ($(DWARF2BTF),y)
@@ -197,16 +198,16 @@ endif
 # Have one program compiled without "-target bpf" to test whether libbpf loads
 # it successfully
 $(OUTPUT)/test_xdp.o: progs/test_xdp.c
-	$(CLANG) $(CLANG_FLAGS) \
-		-O2 -emit-llvm -c $< -o - | \
+	($(CLANG) $(CLANG_FLAGS) -O2 -emit-llvm -c $< -o - || \
+		echo "clang failed") | \
 	$(LLC) -march=bpf -mcpu=$(CPU) $(LLC_FLAGS) -filetype=obj -o $@
 ifeq ($(DWARF2BTF),y)
 	$(BTF_PAHOLE) -J $@
 endif
 
 $(OUTPUT)/%.o: progs/%.c
-	$(CLANG) $(CLANG_FLAGS) \
-		 -O2 -target bpf -emit-llvm -c $< -o - |      \
+	($(CLANG) $(CLANG_FLAGS) -O2 -target bpf -emit-llvm -c $< -o - || \
+		echo "clang failed") | \
 	$(LLC) -march=bpf -mcpu=$(CPU) $(LLC_FLAGS) -filetype=obj -o $@
 ifeq ($(DWARF2BTF),y)
 	$(BTF_PAHOLE) -J $@
-- 
2.20.1

[PATCH AUTOSEL 5.2 45/85] ISDN: hfcsusb: checking idx of ep configuration

[Sasha Levin]

From: Phong Tran <tranmanphong@gmail.com>

[ Upstream commit f384e62a82ba5d85408405fdd6aeff89354deaa9 ]

The syzbot test with random endpoint address which made the idx is
overflow in the table of endpoint configuations.

this adds the checking for fixing the error report from
syzbot

KASAN: stack-out-of-bounds Read in hfcsusb_probe [1]
The patch tested by syzbot [2]

Reported-by: syzbot+8750abbc3a46ef47d509@syzkaller.appspotmail.com

[1]:
https://syzkaller.appspot.com/bug?id=30a04378dac680c5d521304a00a86156bb913522
[2]:
https://groups.google.com/d/msg/syzkaller-bugs/_6HBdge8F3E/OJn7wVNpBAAJ

Signed-off-by: Phong Tran <tranmanphong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/isdn/hardware/mISDN/hfcsusb.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/isdn/hardware/mISDN/hfcsusb.c b/drivers/isdn/hardware/mISDN/hfcsusb.c
index 4c99739b937e..0e224232f746 100644
--- a/drivers/isdn/hardware/mISDN/hfcsusb.c
+++ b/drivers/isdn/hardware/mISDN/hfcsusb.c
@@ -1955,6 +1955,9 @@ hfcsusb_probe(struct usb_interface *intf, const struct usb_device_id *id)
 
 				/* get endpoint base */
 				idx = ((ep_addr & 0x7f) - 1) * 2;
+				if (idx > 15)
+					return -EIO;
+
 				if (ep_addr & 0x80)
 					idx++;
 				attr = ep->desc.bmAttributes;
-- 
2.20.1

[PATCH AUTOSEL 5.2 47/85] bpf: fix BTF verifier size resolution logic

[Sasha Levin]

From: Andrii Nakryiko <andriin@fb.com>

[ Upstream commit 1acc5d5c5832da9a98b22374a8fae08ffe31b3f8 ]

BTF verifier has a size resolution bug which in some circumstances leads to
invalid size resolution for, e.g., TYPEDEF modifier.  This happens if we have
[1] PTR -> [2] TYPEDEF -> [3] ARRAY, in which case due to being in pointer
context ARRAY size won't be resolved (because for pointer it doesn't matter, so
it's a sink in pointer context), but it will be permanently remembered as zero
for TYPEDEF and TYPEDEF will be marked as RESOLVED. Eventually ARRAY size will
be resolved correctly, but TYPEDEF resolved_size won't be updated anymore.
This, subsequently, will lead to erroneous map creation failure, if that
TYPEDEF is specified as either key or value, as key_size/value_size won't
correspond to resolved size of TYPEDEF (kernel will believe it's zero).

Note, that if BTF was ordered as [1] ARRAY <- [2] TYPEDEF <- [3] PTR, this
won't be a problem, as by the time we get to TYPEDEF, ARRAY's size is already
calculated and stored.

This bug manifests itself in rejecting BTF-defined maps that use array
typedef as a value type:

typedef int array_t[16];

struct {
    __uint(type, BPF_MAP_TYPE_ARRAY);
    __type(value, array_t); /* i.e., array_t *value; */
} test_map SEC(".maps");

The fix consists on not relying on modifier's resolved_size and instead using
modifier's resolved_id (type ID for "concrete" type to which modifier
eventually resolves) and doing size determination for that resolved type. This
allow to preserve existing "early DFS termination" logic for PTR or
STRUCT_OR_ARRAY contexts, but still do correct size determination for modifier
types.

Fixes: eb3f595dab40 ("bpf: btf: Validate type reference")
Cc: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 kernel/bpf/btf.c | 19 ++++++++++++-------
 1 file changed, 12 insertions(+), 7 deletions(-)

diff --git a/kernel/bpf/btf.c b/kernel/bpf/btf.c
index cad09858a5f2..8614102971da 100644
--- a/kernel/bpf/btf.c
+++ b/kernel/bpf/btf.c
@@ -1073,11 +1073,18 @@ const struct btf_type *btf_type_id_size(const struct btf *btf,
 				 !btf_type_is_var(size_type)))
 			return NULL;
 
-		size = btf->resolved_sizes[size_type_id];
 		size_type_id = btf->resolved_ids[size_type_id];
 		size_type = btf_type_by_id(btf, size_type_id);
 		if (btf_type_nosize_or_null(size_type))
 			return NULL;
+		else if (btf_type_has_size(size_type))
+			size = size_type->size;
+		else if (btf_type_is_array(size_type))
+			size = btf->resolved_sizes[size_type_id];
+		else if (btf_type_is_ptr(size_type))
+			size = sizeof(void *);
+		else
+			return NULL;
 	}
 
 	*type_id = size_type_id;
@@ -1602,7 +1609,6 @@ static int btf_modifier_resolve(struct btf_verifier_env *env,
 	const struct btf_type *next_type;
 	u32 next_type_id = t->type;
 	struct btf *btf = env->btf;
-	u32 next_type_size = 0;
 
 	next_type = btf_type_by_id(btf, next_type_id);
 	if (!next_type || btf_type_is_resolve_source_only(next_type)) {
@@ -1620,7 +1626,7 @@ static int btf_modifier_resolve(struct btf_verifier_env *env,
 	 * save us a few type-following when we use it later (e.g. in
 	 * pretty print).
 	 */
-	if (!btf_type_id_size(btf, &next_type_id, &next_type_size)) {
+	if (!btf_type_id_size(btf, &next_type_id, NULL)) {
 		if (env_type_is_resolved(env, next_type_id))
 			next_type = btf_type_id_resolve(btf, &next_type_id);
 
@@ -1633,7 +1639,7 @@ static int btf_modifier_resolve(struct btf_verifier_env *env,
 		}
 	}
 
-	env_stack_pop_resolved(env, next_type_id, next_type_size);
+	env_stack_pop_resolved(env, next_type_id, 0);
 
 	return 0;
 }
@@ -1645,7 +1651,6 @@ static int btf_var_resolve(struct btf_verifier_env *env,
 	const struct btf_type *t = v->t;
 	u32 next_type_id = t->type;
 	struct btf *btf = env->btf;
-	u32 next_type_size;
 
 	next_type = btf_type_by_id(btf, next_type_id);
 	if (!next_type || btf_type_is_resolve_source_only(next_type)) {
@@ -1675,12 +1680,12 @@ static int btf_var_resolve(struct btf_verifier_env *env,
 	 * forward types or similar that would resolve to size of
 	 * zero is allowed.
 	 */
-	if (!btf_type_id_size(btf, &next_type_id, &next_type_size)) {
+	if (!btf_type_id_size(btf, &next_type_id, NULL)) {
 		btf_verifier_log_type(env, v->t, "Invalid type_id");
 		return -EINVAL;
 	}
 
-	env_stack_pop_resolved(env, next_type_id, next_type_size);
+	env_stack_pop_resolved(env, next_type_id, 0);
 
 	return 0;
 }
-- 
2.20.1

[PATCH AUTOSEL 5.2 48/85] libbpf: fix another GCC8 warning for strncpy

[Sasha Levin]

From: Andrii Nakryiko <andriin@fb.com>

[ Upstream commit 763ff0e7d9c72e7094b31e7fb84a859be9325635 ]

Similar issue was fixed in cdfc7f888c2a ("libbpf: fix GCC8 warning for
strncpy") already. This one was missed. Fixing now.

Cc: Magnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: Magnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 tools/lib/bpf/xsk.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/tools/lib/bpf/xsk.c b/tools/lib/bpf/xsk.c
index 38667b62f1fe..aa37005209aa 100644
--- a/tools/lib/bpf/xsk.c
+++ b/tools/lib/bpf/xsk.c
@@ -561,7 +561,8 @@ int xsk_socket__create(struct xsk_socket **xsk_ptr, const char *ifname,
 		err = -errno;
 		goto out_socket;
 	}
-	strncpy(xsk->ifname, ifname, IFNAMSIZ);
+	strncpy(xsk->ifname, ifname, IFNAMSIZ - 1);
+	xsk->ifname[IFNAMSIZ - 1] = '\0';
 
 	err = xsk_set_xdp_socket_config(&xsk->config, usr_config);
 	if (err)
-- 
2.20.1

[PATCH AUTOSEL 5.2 49/85] be2net: Signal that the device cannot transmit during reconfiguration

[Sasha Levin]

From: Benjamin Poirier <bpoirier@suse.com>

[ Upstream commit 7429c6c0d9cb086d8e79f0d2a48ae14851d2115e ]

While changing the number of interrupt channels, be2net stops adapter
operation (including netif_tx_disable()) but it doesn't signal that it
cannot transmit. This may lead dev_watchdog() to falsely trigger during
that time.

Add the missing call to netif_carrier_off(), following the pattern used in
many other drivers. netif_carrier_on() is already taken care of in
be_open().

Signed-off-by: Benjamin Poirier <bpoirier@suse.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/net/ethernet/emulex/benet/be_main.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/emulex/benet/be_main.c b/drivers/net/ethernet/emulex/benet/be_main.c
index 82015c8a5ed7..b7a246b33599 100644
--- a/drivers/net/ethernet/emulex/benet/be_main.c
+++ b/drivers/net/ethernet/emulex/benet/be_main.c
@@ -4697,8 +4697,12 @@ int be_update_queues(struct be_adapter *adapter)
 	struct net_device *netdev = adapter->netdev;
 	int status;
 
-	if (netif_running(netdev))
+	if (netif_running(netdev)) {
+		/* device cannot transmit now, avoid dev_watchdog timeouts */
+		netif_carrier_off(netdev);
+
 		be_close(netdev);
+	}
 
 	be_cancel_worker(adapter);
 
-- 
2.20.1

[PATCH AUTOSEL 5.2 71/85] mlxsw: spectrum_dcb: Configure DSCP map as the last rule is removed

[Sasha Levin]

From: Petr Machata <petrm@mellanox.com>

[ Upstream commit dedfde2fe1c4ccf27179fcb234e2112d065c39bb ]

Spectrum systems use DSCP rewrite map to update DSCP field in egressing
packets to correspond to priority that the packet has. Whether rewriting
will take place is determined at the point when the packet ingresses the
switch: if the port is in Trust L3 mode, packet priority is determined from
the DSCP map at the port, and DSCP rewrite will happen. If the port is in
Trust L2 mode, 802.1p is used for packet prioritization, and no DSCP
rewrite will happen.

The driver determines the port trust mode based on whether any DSCP
prioritization rules are in effect at given port. If there are any, trust
level is L3, otherwise it's L2. When the last DSCP rule is removed, the
port is switched to trust L2. Under that scenario, if DSCP of a packet
should be rewritten, it should be rewritten to 0.

However, when switching to Trust L2, the driver neglects to also update the
DSCP rewrite map. The last DSCP rule thus remains in effect, and packets
egressing through this port, if they have the right priority, will have
their DSCP set according to this rule.

Fix by first configuring the rewrite map, and only then switching to trust
L2 and bailing out.

Fixes: b2b1dab6884e ("mlxsw: spectrum: Support ieee_setapp, ieee_delapp")
Signed-off-by: Petr Machata <petrm@mellanox.com>
Reported-by: Alex Veber <alexve@mellanox.com>
Tested-by: Alex Veber <alexve@mellanox.com>
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 .../net/ethernet/mellanox/mlxsw/spectrum_dcb.c   | 16 ++++++++--------
 1 file changed, 8 insertions(+), 8 deletions(-)

diff --git a/drivers/net/ethernet/mellanox/mlxsw/spectrum_dcb.c b/drivers/net/ethernet/mellanox/mlxsw/spectrum_dcb.c
index b25048c6c761..21296fa7f7fb 100644
--- a/drivers/net/ethernet/mellanox/mlxsw/spectrum_dcb.c
+++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum_dcb.c
@@ -408,14 +408,6 @@ static int mlxsw_sp_port_dcb_app_update(struct mlxsw_sp_port *mlxsw_sp_port)
 	have_dscp = mlxsw_sp_port_dcb_app_prio_dscp_map(mlxsw_sp_port,
 							&prio_map);
 
-	if (!have_dscp) {
-		err = mlxsw_sp_port_dcb_toggle_trust(mlxsw_sp_port,
-					MLXSW_REG_QPTS_TRUST_STATE_PCP);
-		if (err)
-			netdev_err(mlxsw_sp_port->dev, "Couldn't switch to trust L2\n");
-		return err;
-	}
-
 	mlxsw_sp_port_dcb_app_dscp_prio_map(mlxsw_sp_port, default_prio,
 					    &dscp_map);
 	err = mlxsw_sp_port_dcb_app_update_qpdpm(mlxsw_sp_port,
@@ -432,6 +424,14 @@ static int mlxsw_sp_port_dcb_app_update(struct mlxsw_sp_port *mlxsw_sp_port)
 		return err;
 	}
 
+	if (!have_dscp) {
+		err = mlxsw_sp_port_dcb_toggle_trust(mlxsw_sp_port,
+					MLXSW_REG_QPTS_TRUST_STATE_PCP);
+		if (err)
+			netdev_err(mlxsw_sp_port->dev, "Couldn't switch to trust L2\n");
+		return err;
+	}
+
 	err = mlxsw_sp_port_dcb_toggle_trust(mlxsw_sp_port,
 					     MLXSW_REG_QPTS_TRUST_STATE_DSCP);
 	if (err) {
-- 
2.20.1

[PATCH AUTOSEL 5.2 80/85] bnxt_en: Fix VNIC accounting when enabling aRFS on 57500 chips.

[Sasha Levin]

From: Michael Chan <michael.chan@broadcom.com>

[ Upstream commit 9b3d15e6b05e0b916be5fbd915f90300a403098b ]

Unlike legacy chips, 57500 chips don't need additional VNIC resources
for aRFS/ntuple.  Fix the code accordingly so that we don't reserve
and allocate additional VNICs on 57500 chips.  Without this patch,
the driver is failing to initialize when it tries to allocate extra
VNICs.

Fixes: ac33906c67e2 ("bnxt_en: Add support for aRFS on 57500 chips.")
Signed-off-by: Michael Chan <michael.chan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/net/ethernet/broadcom/bnxt/bnxt.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.c b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
index f758b2e0591f..9a2a0d24d20d 100644
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt.c
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
@@ -3022,7 +3022,7 @@ static int bnxt_alloc_vnics(struct bnxt *bp)
 	int num_vnics = 1;
 
 #ifdef CONFIG_RFS_ACCEL
-	if (bp->flags & BNXT_FLAG_RFS)
+	if ((bp->flags & (BNXT_FLAG_RFS | BNXT_FLAG_CHIP_P5)) == BNXT_FLAG_RFS)
 		num_vnics += bp->rx_nr_rings;
 #endif
 
@@ -7124,6 +7124,9 @@ static int bnxt_alloc_rfs_vnics(struct bnxt *bp)
 #ifdef CONFIG_RFS_ACCEL
 	int i, rc = 0;
 
+	if (bp->flags & BNXT_FLAG_CHIP_P5)
+		return 0;
+
 	for (i = 0; i < bp->rx_nr_rings; i++) {
 		struct bnxt_vnic_info *vnic;
 		u16 vnic_id = i + 1;
@@ -9587,7 +9590,7 @@ int bnxt_check_rings(struct bnxt *bp, int tx, int rx, bool sh, int tcs,
 		return -ENOMEM;
 
 	vnics = 1;
-	if (bp->flags & BNXT_FLAG_RFS)
+	if ((bp->flags & (BNXT_FLAG_RFS | BNXT_FLAG_CHIP_P5)) == BNXT_FLAG_RFS)
 		vnics += rx_rings;
 
 	if (bp->flags & BNXT_FLAG_AGG_RINGS)
-- 
2.20.1

[PATCH AUTOSEL 5.2 82/85] bpf: Disable GCC -fgcse optimization for ___bpf_prog_run()

[Sasha Levin]

From: Josh Poimboeuf <jpoimboe@redhat.com>

[ Upstream commit 3193c0836f203a91bef96d88c64cccf0be090d9c ]

On x86-64, with CONFIG_RETPOLINE=n, GCC's "global common subexpression
elimination" optimization results in ___bpf_prog_run()'s jumptable code
changing from this:

	select_insn:
		jmp *jumptable(, %rax, 8)
		...
	ALU64_ADD_X:
		...
		jmp *jumptable(, %rax, 8)
	ALU_ADD_X:
		...
		jmp *jumptable(, %rax, 8)

to this:

	select_insn:
		mov jumptable, %r12
		jmp *(%r12, %rax, 8)
		...
	ALU64_ADD_X:
		...
		jmp *(%r12, %rax, 8)
	ALU_ADD_X:
		...
		jmp *(%r12, %rax, 8)

The jumptable address is placed in a register once, at the beginning of
the function.  The function execution can then go through multiple
indirect jumps which rely on that same register value.  This has a few
issues:

1) Objtool isn't smart enough to be able to track such a register value
   across multiple recursive indirect jumps through the jump table.

2) With CONFIG_RETPOLINE enabled, this optimization actually results in
   a small slowdown.  I measured a ~4.7% slowdown in the test_bpf
   "tcpdump port 22" selftest.

   This slowdown is actually predicted by the GCC manual:

     Note: When compiling a program using computed gotos, a GCC
     extension, you may get better run-time performance if you
     disable the global common subexpression elimination pass by
     adding -fno-gcse to the command line.

So just disable the optimization for this function.

Fixes: e55a73251da3 ("bpf: Fix ORC unwinding in non-JIT BPF code")
Reported-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/30c3ca29ba037afcbd860a8672eef0021addf9fe.1563413318.git.jpoimboe@redhat.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 include/linux/compiler-gcc.h   | 2 ++
 include/linux/compiler_types.h | 4 ++++
 kernel/bpf/core.c              | 2 +-
 3 files changed, 7 insertions(+), 1 deletion(-)

diff --git a/include/linux/compiler-gcc.h b/include/linux/compiler-gcc.h
index e8579412ad21..d7ee4c6bad48 100644
--- a/include/linux/compiler-gcc.h
+++ b/include/linux/compiler-gcc.h
@@ -170,3 +170,5 @@
 #else
 #define __diag_GCC_8(s)
 #endif
+
+#define __no_fgcse __attribute__((optimize("-fno-gcse")))
diff --git a/include/linux/compiler_types.h b/include/linux/compiler_types.h
index 19e58b9138a0..0454d82f8bd8 100644
--- a/include/linux/compiler_types.h
+++ b/include/linux/compiler_types.h
@@ -187,6 +187,10 @@ struct ftrace_likely_data {
 #define asm_volatile_goto(x...) asm goto(x)
 #endif
 
+#ifndef __no_fgcse
+# define __no_fgcse
+#endif
+
 /* Are two types/vars the same type (ignoring qualifiers)? */
 #define __same_type(a, b) __builtin_types_compatible_p(typeof(a), typeof(b))
 
diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c
index 080e2bb644cc..ebfd189916dc 100644
--- a/kernel/bpf/core.c
+++ b/kernel/bpf/core.c
@@ -1295,7 +1295,7 @@ bool bpf_opcode_in_insntable(u8 code)
  *
  * Decode and execute eBPF instructions.
  */
-static u64 ___bpf_prog_run(u64 *regs, const struct bpf_insn *insn, u64 *stack)
+static u64 __no_fgcse ___bpf_prog_run(u64 *regs, const struct bpf_insn *insn, u64 *stack)
 {
 #define BPF_INSN_2_LBL(x, y)    [BPF_##x | BPF_##y] = &&x##_##y
 #define BPF_INSN_3_LBL(x, y, z) [BPF_##x | BPF_##y | BPF_##z] = &&x##_##y##_##z
-- 
2.20.1