When running test seccomp_bpf the following splat occurs:
[ RUN ]
global.secseccomp_bpf.c:2136:global.detect_seccomp_filter_flags:Expected 22
(22) == (*__errno_location ()) (14)
seccomp_bpf.c:2138:global.detect_seccomp_filter_flags:Failed to detect that an
unknown
filter flag (0x8) is unsupported! Does a new flag need to be added to this
test?
[ 2155.677841] BUG: assuming atomic context at kernel/seccomp.c:271
[ 2155.689351] in_atomic(): 0, irqs_disabled(): 0, pid: 28540, name: seccomp_bpf
[ 2155.696597] INFO: lockdep is turned off.
[ 2155.700605] CPU: 5 PID: 28540 Comm: seccomp_bpf Tainted: G W
5.0.0-rc7-next-20190220 #1
[ 2155.709972] Hardware name: HiKey Development Board (DT)
[ 2155.715232] Call trace:
[ 2155.717710] dump_backtrace+0x0/0x160
[ 2155.721399] show_stack+0x24/0x30
[ 2155.724742] dump_stack+0xc8/0x114
[ 2155.728172] __cant_sleep+0xf0/0x108
[ 2155.731777] __seccomp_filter+0x8c/0x5c8
[ 2155.735727] __secure_computing+0x4c/0xe8
[ 2155.739767] syscall_trace_enter+0xf8/0x2b8
[ 2155.743982] el0_svc_common+0xf0/0x130
[ 2155.747758] el0_svc_handler+0x38/0x78
[ 2155.751534] el0_svc+0x8/0xc
Rework so that preemption is disabled when we loop over function
'BPF_PROG_RUN(...)'.
Commit 568f196756ad ("bpf: check that BPF programs run with preemption
disabled")
highlighted the issue.
Suggested-by: Arnd Bergmann <a...@arndb.de>
Signed-off-by: Anders Roxell <anders.rox...@linaro.org>
---
lib/test_bpf.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/lib/test_bpf.c b/lib/test_bpf.c
index f3e570722a7e..0845f635f404 100644
--- a/lib/test_bpf.c
+++ b/lib/test_bpf.c
@@ -6668,12 +6668,14 @@ static int __run_one(const struct bpf_prog *fp, const
void *data,
u64 start, finish;
int ret = 0, i;
+ preempt_disable();
start = ktime_get_ns();
for (i = 0; i < runs; i++)
ret = BPF_PROG_RUN(fp, data);
finish = ktime_get_ns();
+ preempt_enable();
*duration = finish - start;
do_div(*duration, runs);
--
2.11.0
