From: Jiong Wang <jiong.wang(a)netronome.com>
[ Upstream commit e434b8cdf788568ba65a0a0fd9f3cb41f3ca1803 ]
Currently, the destination register is marked as unknown for 32-bit
sub-register move (BPF_MOV | BPF_ALU) whenever the source register type is
SCALAR_VALUE.
This is too conservative that some valid cases will be rejected.
Especially, this may turn a constant scalar value into unknown value that
could break some assumptions of verifier.
For example, test_l4lb_noinline.c has the following C code:
struct real_definition *dst
1: if (!get_packet_dst(&dst, &pckt, vip_info, is_ipv6))
2: return TC_ACT_SHOT;
3:
4: if (dst->flags & F_IPV6) {
get_packet_dst is responsible for initializing "dst" into valid pointer and
return true (1), otherwise return false (0). The compiled instruction
sequence using alu32 will be:
412: (54) (u32) r7 &= (u32) 1
413: (bc) (u32) r0 = (u32) r7
414: (95) exit
insn 413, a BPF_MOV | BPF_ALU, however will turn r0 into unknown value even
r7 contains SCALAR_VALUE 1.
This causes trouble when verifier is walking the code path that hasn't
initialized "dst" inside get_packet_dst, for which case 0 is returned and
we would then expect verifier concluding line 1 in the above C code pass
the "if" check, therefore would skip fall through path starting at line 4.
Now, because r0 returned from callee has became unknown value, so verifier
won't skip analyzing path starting at line 4 and "dst->flags" requires
dereferencing the pointer "dst" which actually hasn't be initialized for
this path.
This patch relaxed the code marking sub-register move destination. For a
SCALAR_VALUE, it is safe to just copy the value from source then truncate
it into 32-bit.
A unit test also included to demonstrate this issue. This test will fail
before this patch.
This relaxation could let verifier skipping more paths for conditional
comparison against immediate. It also let verifier recording a more
accurate/strict value for one register at one state, if this state end up
with going through exit without rejection and it is used for state
comparison later, then it is possible an inaccurate/permissive value is
better. So the real impact on verifier processed insn number is complex.
But in all, without this fix, valid program could be rejected.
>From real benchmarking on kernel selftests and Cilium bpf tests, there is
no impact on processed instruction number when tests ares compiled with
default compilation options. There is slightly improvements when they are
compiled with -mattr=+alu32 after this patch.
Also, test_xdp_noinline/-mattr=+alu32 now passed verification. It is
rejected before this fix.
Insn processed before/after this patch:
default -mattr=+alu32
Kernel selftest
===
test_xdp.o 371/371 369/369
test_l4lb.o 6345/6345 5623/5623
test_xdp_noinline.o 2971/2971 rejected/2727
test_tcp_estates.o 429/429 430/430
Cilium bpf
===
bpf_lb-DLB_L3.o: 2085/2085 1685/1687
bpf_lb-DLB_L4.o: 2287/2287 1986/1982
bpf_lb-DUNKNOWN.o: 690/690 622/622
bpf_lxc.o: 95033/95033 N/A
bpf_netdev.o: 7245/7245 N/A
bpf_overlay.o: 2898/2898 3085/2947
NOTE:
- bpf_lxc.o and bpf_netdev.o compiled by -mattr=+alu32 are rejected by
verifier due to another issue inside verifier on supporting alu32
binary.
- Each cilium bpf program could generate several processed insn number,
above number is sum of them.
v1->v2:
- Restrict the change on SCALAR_VALUE.
- Update benchmark numbers on Cilium bpf tests.
Signed-off-by: Jiong Wang <jiong.wang(a)netronome.com>
Signed-off-by: Alexei Starovoitov <ast(a)kernel.org>
Signed-off-by: Sasha Levin <sashal(a)kernel.org>
---
kernel/bpf/verifier.c | 16 ++++++++++++----
tools/testing/selftests/bpf/test_verifier.c | 13 +++++++++++++
2 files changed, 25 insertions(+), 4 deletions(-)
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index 89cea3ed535d..341806668f03 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -3285,12 +3285,15 @@ static int check_alu_op(struct bpf_verifier_env *env, struct bpf_insn *insn)
return err;
if (BPF_SRC(insn->code) == BPF_X) {
+ struct bpf_reg_state *src_reg = regs + insn->src_reg;
+ struct bpf_reg_state *dst_reg = regs + insn->dst_reg;
+
if (BPF_CLASS(insn->code) == BPF_ALU64) {
/* case: R1 = R2
* copy register state to dest reg
*/
- regs[insn->dst_reg] = regs[insn->src_reg];
- regs[insn->dst_reg].live |= REG_LIVE_WRITTEN;
+ *dst_reg = *src_reg;
+ dst_reg->live |= REG_LIVE_WRITTEN;
} else {
/* R1 = (u32) R2 */
if (is_pointer_value(env, insn->src_reg)) {
@@ -3298,9 +3301,14 @@ static int check_alu_op(struct bpf_verifier_env *env, struct bpf_insn *insn)
"R%d partial copy of pointer\n",
insn->src_reg);
return -EACCES;
+ } else if (src_reg->type == SCALAR_VALUE) {
+ *dst_reg = *src_reg;
+ dst_reg->live |= REG_LIVE_WRITTEN;
+ } else {
+ mark_reg_unknown(env, regs,
+ insn->dst_reg);
}
- mark_reg_unknown(env, regs, insn->dst_reg);
- coerce_reg_to_size(®s[insn->dst_reg], 4);
+ coerce_reg_to_size(dst_reg, 4);
}
} else {
/* case: R = imm
diff --git a/tools/testing/selftests/bpf/test_verifier.c b/tools/testing/selftests/bpf/test_verifier.c
index e436b67f2426..9db5a7378f40 100644
--- a/tools/testing/selftests/bpf/test_verifier.c
+++ b/tools/testing/selftests/bpf/test_verifier.c
@@ -2748,6 +2748,19 @@ static struct bpf_test tests[] = {
.result_unpriv = REJECT,
.result = ACCEPT,
},
+ {
+ "alu32: mov u32 const",
+ .insns = {
+ BPF_MOV32_IMM(BPF_REG_7, 0),
+ BPF_ALU32_IMM(BPF_AND, BPF_REG_7, 1),
+ BPF_MOV32_REG(BPF_REG_0, BPF_REG_7),
+ BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 1),
+ BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_7, 0),
+ BPF_EXIT_INSN(),
+ },
+ .result = ACCEPT,
+ .retval = 0,
+ },
{
"unpriv: partial copy of pointer",
.insns = {
--
2.19.1
From: Quentin Monnet <quentin.monnet(a)netronome.com>
[ Upstream commit f96afa767baffba7645f5e10998f5178948bb9aa ]
libbpf is now able to load successfully test_l4lb_noinline.o and
samples/bpf/tracex3_kern.o.
For the test_l4lb_noinline, uncomment related tests from test_libbpf.c
and remove the associated "TODO".
For tracex3_kern.o, instead of loading a program from samples/bpf/ that
might not have been compiled at this stage, try loading a program from
BPF selftests. Since this test case is about loading a program compiled
without the "-target bpf" flag, change the Makefile to compile one
program accordingly (instead of passing the flag for compiling all
programs).
Regarding test_xdp_noinline.o: in its current shape the program fails to
load because it provides no version section, but the loader needs one.
The test was added to make sure that libbpf could load XDP programs even
if they do not provide a version number in a dedicated section. But
libbpf is already capable of doing that: in our case loading fails
because the loader does not know that this is an XDP program (it does
not need to, since it does not attach the program). So trying to load
test_xdp_noinline.o does not bring much here: just delete this subtest.
For the record, the error message obtained with tracex3_kern.o was
fixed by commit e3d91b0ca523 ("tools/libbpf: handle issues with bpf ELF
objects containing .eh_frames")
I have not been abled to reproduce the "libbpf: incorrect bpf_call
opcode" error for test_l4lb_noinline.o, even with the version of libbpf
present at the time when test_libbpf.sh and test_libbpf_open.c were
created.
RFC -> v1:
- Compile test_xdp without the "-target bpf" flag, and try to load it
instead of ../../samples/bpf/tracex3_kern.o.
- Delete test_xdp_noinline.o subtest.
Cc: Jesper Dangaard Brouer <brouer(a)redhat.com>
Signed-off-by: Quentin Monnet <quentin.monnet(a)netronome.com>
Acked-by: Jakub Kicinski <jakub.kicinski(a)netronome.com>
Acked-by: Jesper Dangaard Brouer <brouer(a)redhat.com>
Signed-off-by: Daniel Borkmann <daniel(a)iogearbox.net>
Signed-off-by: Sasha Levin <sashal(a)kernel.org>
---
tools/testing/selftests/bpf/Makefile | 10 ++++++++++
tools/testing/selftests/bpf/test_libbpf.sh | 14 ++++----------
2 files changed, 14 insertions(+), 10 deletions(-)
diff --git a/tools/testing/selftests/bpf/Makefile b/tools/testing/selftests/bpf/Makefile
index fff7fb1285fc..f3f874ba186b 100644
--- a/tools/testing/selftests/bpf/Makefile
+++ b/tools/testing/selftests/bpf/Makefile
@@ -124,6 +124,16 @@ endif
endif
endif
+# Have one program compiled without "-target bpf" to test whether libbpf loads
+# it successfully
+$(OUTPUT)/test_xdp.o: test_xdp.c
+ $(CLANG) $(CLANG_FLAGS) \
+ -O2 -emit-llvm -c $< -o - | \
+ $(LLC) -march=bpf -mcpu=$(CPU) $(LLC_FLAGS) -filetype=obj -o $@
+ifeq ($(DWARF2BTF),y)
+ $(BTF_PAHOLE) -J $@
+endif
+
$(OUTPUT)/%.o: %.c
$(CLANG) $(CLANG_FLAGS) \
-O2 -target bpf -emit-llvm -c $< -o - | \
diff --git a/tools/testing/selftests/bpf/test_libbpf.sh b/tools/testing/selftests/bpf/test_libbpf.sh
index d97dc914cd49..8b1bc96d8e0c 100755
--- a/tools/testing/selftests/bpf/test_libbpf.sh
+++ b/tools/testing/selftests/bpf/test_libbpf.sh
@@ -33,17 +33,11 @@ trap exit_handler 0 2 3 6 9
libbpf_open_file test_l4lb.o
-# TODO: fix libbpf to load noinline functions
-# [warning] libbpf: incorrect bpf_call opcode
-#libbpf_open_file test_l4lb_noinline.o
+# Load a program with BPF-to-BPF calls
+libbpf_open_file test_l4lb_noinline.o
-# TODO: fix test_xdp_meta.c to load with libbpf
-# [warning] libbpf: test_xdp_meta.o doesn't provide kernel version
-#libbpf_open_file test_xdp_meta.o
-
-# TODO: fix libbpf to handle .eh_frame
-# [warning] libbpf: relocation failed: no section(10)
-#libbpf_open_file ../../../../samples/bpf/tracex3_kern.o
+# Load a program compiled without the "-target bpf" flag
+libbpf_open_file test_xdp.o
# Success
exit 0
--
2.19.1
From: Jiong Wang <jiong.wang(a)netronome.com>
[ Upstream commit e434b8cdf788568ba65a0a0fd9f3cb41f3ca1803 ]
Currently, the destination register is marked as unknown for 32-bit
sub-register move (BPF_MOV | BPF_ALU) whenever the source register type is
SCALAR_VALUE.
This is too conservative that some valid cases will be rejected.
Especially, this may turn a constant scalar value into unknown value that
could break some assumptions of verifier.
For example, test_l4lb_noinline.c has the following C code:
struct real_definition *dst
1: if (!get_packet_dst(&dst, &pckt, vip_info, is_ipv6))
2: return TC_ACT_SHOT;
3:
4: if (dst->flags & F_IPV6) {
get_packet_dst is responsible for initializing "dst" into valid pointer and
return true (1), otherwise return false (0). The compiled instruction
sequence using alu32 will be:
412: (54) (u32) r7 &= (u32) 1
413: (bc) (u32) r0 = (u32) r7
414: (95) exit
insn 413, a BPF_MOV | BPF_ALU, however will turn r0 into unknown value even
r7 contains SCALAR_VALUE 1.
This causes trouble when verifier is walking the code path that hasn't
initialized "dst" inside get_packet_dst, for which case 0 is returned and
we would then expect verifier concluding line 1 in the above C code pass
the "if" check, therefore would skip fall through path starting at line 4.
Now, because r0 returned from callee has became unknown value, so verifier
won't skip analyzing path starting at line 4 and "dst->flags" requires
dereferencing the pointer "dst" which actually hasn't be initialized for
this path.
This patch relaxed the code marking sub-register move destination. For a
SCALAR_VALUE, it is safe to just copy the value from source then truncate
it into 32-bit.
A unit test also included to demonstrate this issue. This test will fail
before this patch.
This relaxation could let verifier skipping more paths for conditional
comparison against immediate. It also let verifier recording a more
accurate/strict value for one register at one state, if this state end up
with going through exit without rejection and it is used for state
comparison later, then it is possible an inaccurate/permissive value is
better. So the real impact on verifier processed insn number is complex.
But in all, without this fix, valid program could be rejected.
>From real benchmarking on kernel selftests and Cilium bpf tests, there is
no impact on processed instruction number when tests ares compiled with
default compilation options. There is slightly improvements when they are
compiled with -mattr=+alu32 after this patch.
Also, test_xdp_noinline/-mattr=+alu32 now passed verification. It is
rejected before this fix.
Insn processed before/after this patch:
default -mattr=+alu32
Kernel selftest
===
test_xdp.o 371/371 369/369
test_l4lb.o 6345/6345 5623/5623
test_xdp_noinline.o 2971/2971 rejected/2727
test_tcp_estates.o 429/429 430/430
Cilium bpf
===
bpf_lb-DLB_L3.o: 2085/2085 1685/1687
bpf_lb-DLB_L4.o: 2287/2287 1986/1982
bpf_lb-DUNKNOWN.o: 690/690 622/622
bpf_lxc.o: 95033/95033 N/A
bpf_netdev.o: 7245/7245 N/A
bpf_overlay.o: 2898/2898 3085/2947
NOTE:
- bpf_lxc.o and bpf_netdev.o compiled by -mattr=+alu32 are rejected by
verifier due to another issue inside verifier on supporting alu32
binary.
- Each cilium bpf program could generate several processed insn number,
above number is sum of them.
v1->v2:
- Restrict the change on SCALAR_VALUE.
- Update benchmark numbers on Cilium bpf tests.
Signed-off-by: Jiong Wang <jiong.wang(a)netronome.com>
Signed-off-by: Alexei Starovoitov <ast(a)kernel.org>
Signed-off-by: Sasha Levin <sashal(a)kernel.org>
---
kernel/bpf/verifier.c | 16 ++++++++++++----
tools/testing/selftests/bpf/test_verifier.c | 13 +++++++++++++
2 files changed, 25 insertions(+), 4 deletions(-)
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index a81f52b2c92e..eedc7bd4185d 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -3571,12 +3571,15 @@ static int check_alu_op(struct bpf_verifier_env *env, struct bpf_insn *insn)
return err;
if (BPF_SRC(insn->code) == BPF_X) {
+ struct bpf_reg_state *src_reg = regs + insn->src_reg;
+ struct bpf_reg_state *dst_reg = regs + insn->dst_reg;
+
if (BPF_CLASS(insn->code) == BPF_ALU64) {
/* case: R1 = R2
* copy register state to dest reg
*/
- regs[insn->dst_reg] = regs[insn->src_reg];
- regs[insn->dst_reg].live |= REG_LIVE_WRITTEN;
+ *dst_reg = *src_reg;
+ dst_reg->live |= REG_LIVE_WRITTEN;
} else {
/* R1 = (u32) R2 */
if (is_pointer_value(env, insn->src_reg)) {
@@ -3584,9 +3587,14 @@ static int check_alu_op(struct bpf_verifier_env *env, struct bpf_insn *insn)
"R%d partial copy of pointer\n",
insn->src_reg);
return -EACCES;
+ } else if (src_reg->type == SCALAR_VALUE) {
+ *dst_reg = *src_reg;
+ dst_reg->live |= REG_LIVE_WRITTEN;
+ } else {
+ mark_reg_unknown(env, regs,
+ insn->dst_reg);
}
- mark_reg_unknown(env, regs, insn->dst_reg);
- coerce_reg_to_size(®s[insn->dst_reg], 4);
+ coerce_reg_to_size(dst_reg, 4);
}
} else {
/* case: R = imm
diff --git a/tools/testing/selftests/bpf/test_verifier.c b/tools/testing/selftests/bpf/test_verifier.c
index f8eac4a544f4..444f49176a2d 100644
--- a/tools/testing/selftests/bpf/test_verifier.c
+++ b/tools/testing/selftests/bpf/test_verifier.c
@@ -2903,6 +2903,19 @@ static struct bpf_test tests[] = {
.result_unpriv = REJECT,
.result = ACCEPT,
},
+ {
+ "alu32: mov u32 const",
+ .insns = {
+ BPF_MOV32_IMM(BPF_REG_7, 0),
+ BPF_ALU32_IMM(BPF_AND, BPF_REG_7, 1),
+ BPF_MOV32_REG(BPF_REG_0, BPF_REG_7),
+ BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 1),
+ BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_7, 0),
+ BPF_EXIT_INSN(),
+ },
+ .result = ACCEPT,
+ .retval = 0,
+ },
{
"unpriv: partial copy of pointer",
.insns = {
--
2.19.1
From: Quentin Monnet <quentin.monnet(a)netronome.com>
[ Upstream commit f96afa767baffba7645f5e10998f5178948bb9aa ]
libbpf is now able to load successfully test_l4lb_noinline.o and
samples/bpf/tracex3_kern.o.
For the test_l4lb_noinline, uncomment related tests from test_libbpf.c
and remove the associated "TODO".
For tracex3_kern.o, instead of loading a program from samples/bpf/ that
might not have been compiled at this stage, try loading a program from
BPF selftests. Since this test case is about loading a program compiled
without the "-target bpf" flag, change the Makefile to compile one
program accordingly (instead of passing the flag for compiling all
programs).
Regarding test_xdp_noinline.o: in its current shape the program fails to
load because it provides no version section, but the loader needs one.
The test was added to make sure that libbpf could load XDP programs even
if they do not provide a version number in a dedicated section. But
libbpf is already capable of doing that: in our case loading fails
because the loader does not know that this is an XDP program (it does
not need to, since it does not attach the program). So trying to load
test_xdp_noinline.o does not bring much here: just delete this subtest.
For the record, the error message obtained with tracex3_kern.o was
fixed by commit e3d91b0ca523 ("tools/libbpf: handle issues with bpf ELF
objects containing .eh_frames")
I have not been abled to reproduce the "libbpf: incorrect bpf_call
opcode" error for test_l4lb_noinline.o, even with the version of libbpf
present at the time when test_libbpf.sh and test_libbpf_open.c were
created.
RFC -> v1:
- Compile test_xdp without the "-target bpf" flag, and try to load it
instead of ../../samples/bpf/tracex3_kern.o.
- Delete test_xdp_noinline.o subtest.
Cc: Jesper Dangaard Brouer <brouer(a)redhat.com>
Signed-off-by: Quentin Monnet <quentin.monnet(a)netronome.com>
Acked-by: Jakub Kicinski <jakub.kicinski(a)netronome.com>
Acked-by: Jesper Dangaard Brouer <brouer(a)redhat.com>
Signed-off-by: Daniel Borkmann <daniel(a)iogearbox.net>
Signed-off-by: Sasha Levin <sashal(a)kernel.org>
---
tools/testing/selftests/bpf/Makefile | 10 ++++++++++
tools/testing/selftests/bpf/test_libbpf.sh | 14 ++++----------
2 files changed, 14 insertions(+), 10 deletions(-)
diff --git a/tools/testing/selftests/bpf/Makefile b/tools/testing/selftests/bpf/Makefile
index e39dfb4e7970..ecd79b7fb107 100644
--- a/tools/testing/selftests/bpf/Makefile
+++ b/tools/testing/selftests/bpf/Makefile
@@ -135,6 +135,16 @@ endif
endif
endif
+# Have one program compiled without "-target bpf" to test whether libbpf loads
+# it successfully
+$(OUTPUT)/test_xdp.o: test_xdp.c
+ $(CLANG) $(CLANG_FLAGS) \
+ -O2 -emit-llvm -c $< -o - | \
+ $(LLC) -march=bpf -mcpu=$(CPU) $(LLC_FLAGS) -filetype=obj -o $@
+ifeq ($(DWARF2BTF),y)
+ $(BTF_PAHOLE) -J $@
+endif
+
$(OUTPUT)/%.o: %.c
$(CLANG) $(CLANG_FLAGS) \
-O2 -target bpf -emit-llvm -c $< -o - | \
diff --git a/tools/testing/selftests/bpf/test_libbpf.sh b/tools/testing/selftests/bpf/test_libbpf.sh
index 156d89f1edcc..2989b2e2d856 100755
--- a/tools/testing/selftests/bpf/test_libbpf.sh
+++ b/tools/testing/selftests/bpf/test_libbpf.sh
@@ -33,17 +33,11 @@ trap exit_handler 0 2 3 6 9
libbpf_open_file test_l4lb.o
-# TODO: fix libbpf to load noinline functions
-# [warning] libbpf: incorrect bpf_call opcode
-#libbpf_open_file test_l4lb_noinline.o
+# Load a program with BPF-to-BPF calls
+libbpf_open_file test_l4lb_noinline.o
-# TODO: fix test_xdp_meta.c to load with libbpf
-# [warning] libbpf: test_xdp_meta.o doesn't provide kernel version
-#libbpf_open_file test_xdp_meta.o
-
-# TODO: fix libbpf to handle .eh_frame
-# [warning] libbpf: relocation failed: no section(10)
-#libbpf_open_file ../../../../samples/bpf/tracex3_kern.o
+# Load a program compiled without the "-target bpf" flag
+libbpf_open_file test_xdp.o
# Success
exit 0
--
2.19.1
From: Ahmed Abd El Mawgood <ahmedsoliman(a)mena.vt.edu>
madvise() returns -1 without CONFIG_TRANSPARENT_HUGEPAGE=y. That would
trigger asserts when checking for return value of madvice. Following
similar decision to [1]. I thought it is ok to assume that madvise()
MADV_NOHUGEPAGE failures implies that THP is not supported by host kernel.
Other options was to check for Transparent Huge Page support in
/sys/kernel/mm/transparent_hugepage/enabled.
-- links --
[1] https://lists.gnu.org/archive/html/qemu-devel/2015-11/msg04514.html
Signed-off-by: Ahmed Abd El Mawgood <ahmedsoliman(a)mena.vt.edu>
---
tools/testing/selftests/kvm/lib/kvm_util.c | 21 +++++++++++++++------
1 file changed, 15 insertions(+), 6 deletions(-)
diff --git a/tools/testing/selftests/kvm/lib/kvm_util.c b/tools/testing/selftests/kvm/lib/kvm_util.c
index 1b41e71283d5..437c5bb48061 100644
--- a/tools/testing/selftests/kvm/lib/kvm_util.c
+++ b/tools/testing/selftests/kvm/lib/kvm_util.c
@@ -586,14 +586,23 @@ void vm_userspace_mem_region_add(struct kvm_vm *vm,
src_type == VM_MEM_SRC_ANONYMOUS_THP ? huge_page_size : 1);
/* As needed perform madvise */
- if (src_type == VM_MEM_SRC_ANONYMOUS || src_type == VM_MEM_SRC_ANONYMOUS_THP) {
+ if (src_type == VM_MEM_SRC_ANONYMOUS) {
+ /*
+ * Neglect madvise error because it is ok to not have THP
+ * support in this case.
+ */
+ madvise(region->host_mem, npages * vm->page_size,
+ MADV_NOHUGEPAGE);
+ } else if (src_type == VM_MEM_SRC_ANONYMOUS_THP) {
ret = madvise(region->host_mem, npages * vm->page_size,
- src_type == VM_MEM_SRC_ANONYMOUS ? MADV_NOHUGEPAGE : MADV_HUGEPAGE);
+ MADV_HUGEPAGE);
TEST_ASSERT(ret == 0, "madvise failed,\n"
- " addr: %p\n"
- " length: 0x%lx\n"
- " src_type: %x",
- region->host_mem, npages * vm->page_size, src_type);
+ "Does the kernel have CONFIG_TRANSPARENT_HUGEPAGE=y\n"
+ " addr: %p\n"
+ " length: 0x%lx\n"
+ " src_type: %x\n",
+ region->host_mem, npages * vm->page_size,
+ src_type);
}
region->unused_phy_pages = sparsebit_alloc();
--
2.18.1
Hi Shuah,
CC kbuild, gpio
On Thu, Sep 14, 2017 at 5:34 PM Shuah Khan <shuah(a)kernel.org> wrote:
> bpf test depends on clang and fails to compile when
>
> ------------------------------------------------------
> make -C tools/testing/selftests/bpf run_tests
>
>
> make: clang: Command not found
> Makefile:39: recipe for target '.linux-kselftest/tools/testing/selftests/bpf/test_pkt_access.o' failed
> make: *** [./linux-kselftest/tools/testing/selftests/bpf/test_pkt_access.o] Error 127
> make: Leaving directory '.linux-kselftest/tools/testing/selftests/bpf'
The above failure is indeed due to missing clang.
> With "make TARGETS=bpf kselftest" it fails earlier:
>
> make[3]: Entering directory './linux-kselftest/tools/lib/bpf'
> Makefile:40: tools/scripts/Makefile.arch: No such file or directory
> Makefile:84: tools/build/Makefile.feature: No such file or directory
> Makefile:143: tools/build/Makefile.include: No such file or directory
This is due to srctree being "." instead of the actual source tree,
when invoked as "make kselftest".
When using "make -C tools/testing/selftests", srctree is correct.
tools/testing/selftests/bpf/Makefile has:
$(BPFOBJ): force
$(MAKE) -C $(BPFDIR) OUTPUT=$(OUTPUT)/
to enter the tools/lib/bpf directory to force a build of libbpf.a
Note that tools/gpio has the same issue.
There seem to be _four_ different ways to build kselftests
(Documentation/dev-tools/kselftest.rst):
make kselftest
make O=/path/to/output kselftest
make -C tools/testing/selftests
make O=/path/to/output -C tools/testing/selftests
I'm not so fond of the latter two, as they basically run make from
somewhere inside the tree, which complicates things. I believe we don't
support this anywhere else.
Each of the four seem to have (different) issues. Especially when you
throw cross-compiling into the mix. And care about where installed
headers end up (yes, kselftest calls headers_install internally).
I'm working on fixes for some of them, but I don't know how to fix the
srctree issue.
Anyone with a suggestion?
Thanks!
> make[3]: *** No rule to make target 'tools/build/Makefile.include'. Stop.
> make[3]: Leaving directory '.linux-kselftest/tools/lib/bpf'
> Makefile:34: recipe for target './linux-kselftest/tools/testing/selftests/bpf/libbpf.a' failed
> make[2]: *** [./linux-kselftest/tools/testing/selftests/bpf/libbpf.a] Error 2
> make[2]: Leaving directory './linux-kselftest/tools/testing/selftests/bpf'
> Makefile:69: recipe for target 'all' failed
> make[1]: *** [all] Error 2
> Makefile:1190: recipe for target 'kselftest' failed
> make: *** [kselftest] Error 2
Gr{oetje,eeting}s,
Geert
--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert(a)linux-m68k.org
In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds