bisecting fixing commit since ef244c3088856cf048c77231653b4c92a7b2213c building syzkaller on c9610487d8c10f7b4ffb32764a6720cbbdfe6058 testing commit ef244c3088856cf048c77231653b4c92a7b2213c with gcc (GCC) 8.1.0 kernel signature: 4a1d15c3cc5d8a183387117ff5a8860b190c0543 all runs: crashed: WARNING: suspicious RCU usage in memfd_fcntl testing current HEAD 7d120bf21c05cbe30a679f0feeca884eeaceb069 testing commit 7d120bf21c05cbe30a679f0feeca884eeaceb069 with gcc (GCC) 8.1.0 kernel signature: 5281fdc92e80b1c33e363ffb0be9b93d0bd96a7d all runs: OK # git bisect start 7d120bf21c05cbe30a679f0feeca884eeaceb069 ef244c3088856cf048c77231653b4c92a7b2213c Bisecting: 1037 revisions left to test after this (roughly 10 steps) [ff36ace6c107a3abe90f08e1712650a207eb7327] tools: PCI: Fix broken pcitest compilation testing commit ff36ace6c107a3abe90f08e1712650a207eb7327 with gcc (GCC) 8.1.0 kernel signature: b551d52241fc007b0e5cf95811d72e83ff0bed46 run #0: basic kernel testing failed: failed to copy test binary to VM: failed to run ["scp" "-P" "22" "-F" "/dev/null" "-o" "UserKnownHostsFile=/dev/null" "-o" "BatchMode=yes" "-o" "IdentitiesOnly=yes" "-o" "StrictHostKeyChecking=no" "-o" "ConnectTimeout=10" "-i" "/syzkaller/jobs/linux/workdir/image/key" "/tmp/syz-executor712724092" "root@10.128.1.58:./syz-executor712724092"]: exit status 1 ssh: connect to host 10.128.1.58 port 22: Connection timed out lost connection run #1: OK run #2: OK run #3: OK run #4: OK run #5: OK run #6: OK run #7: OK run #8: OK run #9: OK # git bisect bad ff36ace6c107a3abe90f08e1712650a207eb7327 Bisecting: 518 revisions left to test after this (roughly 9 steps) [23ad83c399b0ac62b6e8cd10352119f3b4116c0b] f2fs: avoid wrong decrypted data from disk testing commit 23ad83c399b0ac62b6e8cd10352119f3b4116c0b with gcc (GCC) 8.1.0 kernel signature: 1a8bbcf30ae5d40d586c9223817c39bfc63ccf85 all runs: crashed: WARNING: suspicious RCU usage in memfd_fcntl # git bisect good 23ad83c399b0ac62b6e8cd10352119f3b4116c0b Bisecting: 259 revisions left to test after this (roughly 8 steps) [57b78e41a397ca520069c13b5552c0a2d20729cc] EDAC: Raise the maximum number of memory controllers testing commit 57b78e41a397ca520069c13b5552c0a2d20729cc with gcc (GCC) 8.1.0 kernel signature: 67252413d1e8a75b1525c4b4cd7b41eaf122d5cb all runs: crashed: WARNING: suspicious RCU usage in memfd_fcntl # git bisect good 57b78e41a397ca520069c13b5552c0a2d20729cc Bisecting: 129 revisions left to test after this (roughly 7 steps) [010af7a8d0aee6c3d75e82a896f00540bc27fa45] RDMA/hns: Bugfix for CM test testing commit 010af7a8d0aee6c3d75e82a896f00540bc27fa45 with gcc (GCC) 8.1.0 kernel signature: 9da85a648bb5a495c807b983b4a41e96863e2fbb all runs: OK # git bisect bad 010af7a8d0aee6c3d75e82a896f00540bc27fa45 Bisecting: 64 revisions left to test after this (roughly 6 steps) [ed220d3dcc791aaab64e3a2e3b3518a1d34f8b9a] ARM: dts: sun8i: h3-h5: ir register size should be the whole memory block testing commit ed220d3dcc791aaab64e3a2e3b3518a1d34f8b9a with gcc (GCC) 8.1.0 kernel signature: 70b110d1ebf12655708b9290f1b4857be611270f all runs: OK # git bisect bad ed220d3dcc791aaab64e3a2e3b3518a1d34f8b9a Bisecting: 32 revisions left to test after this (roughly 5 steps) [ba8c4cc746a55b7eec4d38baa6ca7769194b940a] rtc: armada38x: fix possible race condition testing commit ba8c4cc746a55b7eec4d38baa6ca7769194b940a with gcc (GCC) 8.1.0 kernel signature: 0537e7ad9f8e3ac4cfe57113a1c67ffd0ea33383 all runs: crashed: WARNING: suspicious RCU usage in memfd_fcntl # git bisect good ba8c4cc746a55b7eec4d38baa6ca7769194b940a Bisecting: 16 revisions left to test after this (roughly 4 steps) [4c62337d8f1727f5005e41a141fe42c0154c21f9] net: cdc_ncm: Signedness bug in cdc_ncm_set_dgram_size() testing commit 4c62337d8f1727f5005e41a141fe42c0154c21f9 with gcc (GCC) 8.1.0 kernel signature: fdbd251fa191301cae45ea01aa3286dd81349d40 all runs: OK # git bisect bad 4c62337d8f1727f5005e41a141fe42c0154c21f9 Bisecting: 7 revisions left to test after this (roughly 3 steps) [914834a73b167ec4246e17ada4ecd304657f9ce1] net: phy: mdio-bcm-unimac: mark PM functions as __maybe_unused testing commit 914834a73b167ec4246e17ada4ecd304657f9ce1 with gcc (GCC) 8.1.0 kernel signature: c245e4279d0b748b482c7a3600a68145c4c633f3 all runs: crashed: WARNING: suspicious RCU usage in memfd_fcntl # git bisect good 914834a73b167ec4246e17ada4ecd304657f9ce1 Bisecting: 3 revisions left to test after this (roughly 2 steps) [976e944e005f555e90d92e504a38f8231551925b] spi: mediatek: use correct mata->xfer_len when in fifo transfer testing commit 976e944e005f555e90d92e504a38f8231551925b with gcc (GCC) 8.1.0 kernel signature: 3839411dbde8bef1c78eb657ed2c5f8a51cb250a all runs: OK # git bisect bad 976e944e005f555e90d92e504a38f8231551925b Bisecting: 1 revision left to test after this (roughly 1 step) [e99d64837815753cfc4d8e193e0fc23ce91e3c57] slcan: Fix memory leak in error path testing commit e99d64837815753cfc4d8e193e0fc23ce91e3c57 with gcc (GCC) 8.1.0 kernel signature: 08525f35750c562daaac0cf85f5e732045f551f1 all runs: OK # git bisect bad e99d64837815753cfc4d8e193e0fc23ce91e3c57 Bisecting: 0 revisions left to test after this (roughly 0 steps) [e4cc9c81e2305aabfa9a0e46e17d3895a10ba3d8] memfd: Use radix_tree_deref_slot_protected to avoid the warning. testing commit e4cc9c81e2305aabfa9a0e46e17d3895a10ba3d8 with gcc (GCC) 8.1.0 kernel signature: 83cf7e3b6a5590a4c4dd792e4bc00004c4a8041c all runs: OK # git bisect bad e4cc9c81e2305aabfa9a0e46e17d3895a10ba3d8 e4cc9c81e2305aabfa9a0e46e17d3895a10ba3d8 is the first bad commit commit e4cc9c81e2305aabfa9a0e46e17d3895a10ba3d8 Author: zhong jiang Date: Mon Nov 18 11:26:08 2019 +0800 memfd: Use radix_tree_deref_slot_protected to avoid the warning. The commit 99b45e7a1ba1 ("memfd: Fix locking when tagging pins") introduces the following warning messages. *WARNING: suspicious RCU usage in memfd_wait_for_pins* It is because we still use radix_tree_deref_slot without read_rcu_lock. We should use radix_tree_deref_slot_protected instead in the case. Cc: stable@vger.kernel.org Fixes: 99b45e7a1ba1 ("memfd: Fix locking when tagging pins") Signed-off-by: zhong jiang Reviewed-by: Matthew Wilcox (Oracle) Signed-off-by: Greg Kroah-Hartman mm/memfd.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) culprit signature: 83cf7e3b6a5590a4c4dd792e4bc00004c4a8041c parent signature: c245e4279d0b748b482c7a3600a68145c4c633f3 revisions tested: 13, total time: 3h27m24.577280609s (build: 1h50m12.772460585s, test: 1h35m27.047588894s) first good commit: e4cc9c81e2305aabfa9a0e46e17d3895a10ba3d8 memfd: Use radix_tree_deref_slot_protected to avoid the warning. cc: ["gregkh@linuxfoundation.org" "willy@infradead.org" "zhongjiang@huawei.com"]