bisecting fixing commit since 3dbdb38e286903ec220aaf1fb29a8d94297da246 building syzkaller on 55aa55c24fe77aae07d530662f91b4d50c4990f0 testing commit 3dbdb38e286903ec220aaf1fb29a8d94297da246 compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.35.2 kernel signature: 278798db997e4e122507bccc0f9fb2f5053d80132fc32a0fd5614526bb74064b run #0: basic kernel testing failed: BUG: sleeping function called from invalid context in stack_depot_save run #1: basic kernel testing failed: possible deadlock in fs_reclaim_acquire run #2: crashed: INFO: task hung in hwrng_register run #3: crashed: INFO: task hung in drop_current_rng run #4: crashed: INFO: task hung in hwrng_register run #5: crashed: INFO: task hung in hwrng_register run #6: crashed: INFO: task hung in hwrng_register run #7: crashed: INFO: task hung in drop_current_rng run #8: crashed: INFO: task hung in hwrng_register run #9: crashed: INFO: task hung in hwrng_register run #10: crashed: INFO: task hung in hwrng_register run #11: crashed: INFO: task hung in hwrng_register run #12: crashed: INFO: task hung in hwrng_register run #13: crashed: INFO: task hung in hwrng_register run #14: crashed: INFO: task hung in hwrng_register run #15: crashed: INFO: task hung in drop_current_rng run #16: crashed: INFO: task hung in drop_current_rng run #17: crashed: INFO: task hung in hwrng_register run #18: crashed: INFO: task hung in hwrng_register run #19: crashed: INFO: task hung in drop_current_rng testing current HEAD 58e1100fdc5990b0cc0d4beaf2562a92e621ac7d testing commit 58e1100fdc5990b0cc0d4beaf2562a92e621ac7d compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.35.2 kernel signature: d311739c990d69598ecfb0856b7ab35e843452990a5a5ef784053f2b0568333d all runs: OK # git bisect start 58e1100fdc5990b0cc0d4beaf2562a92e621ac7d 3dbdb38e286903ec220aaf1fb29a8d94297da246 Bisecting: 17791 revisions left to test after this (roughly 14 steps) [27151f177827d478508e756c7657273261aaf8a9] Merge tag 'perf-tools-for-v5.15-2021-09-04' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux testing commit 27151f177827d478508e756c7657273261aaf8a9 compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.35.2 kernel signature: bc0ea5733ddecbf53a4b0007364b75217cf32ed541f41c2e938d05ad01f08d73 run #0: crashed: KFENCE: use-after-free in kvm_fastop_exception run #1: crashed: INFO: task hung in hwrng_register run #2: crashed: INFO: task hung in hwrng_register run #3: crashed: INFO: task hung in hwrng_register run #4: crashed: INFO: task hung in hwrng_register run #5: crashed: INFO: task hung in hwrng_register run #6: crashed: INFO: task hung in hwrng_register run #7: crashed: INFO: task hung in hwrng_register run #8: crashed: INFO: task hung in drop_current_rng run #9: crashed: INFO: task hung in hwrng_register # git bisect good 27151f177827d478508e756c7657273261aaf8a9 Bisecting: 8894 revisions left to test after this (roughly 13 steps) [833db72142b93a89211c1e43ca0a1e2e16457756] Merge tag 'pm-5.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm testing commit 833db72142b93a89211c1e43ca0a1e2e16457756 compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.35.2 kernel signature: 0c2e2485daa5e6ee88d01813c6788f77e7001040c00ea6977ad7008ce33dc135 run #0: crashed: INFO: task hung in hwrng_register run #1: crashed: INFO: task hung in hwrng_register run #2: crashed: INFO: task hung in drop_current_rng run #3: crashed: INFO: task hung in hwrng_register run #4: crashed: INFO: task hung in hwrng_register run #5: crashed: INFO: task hung in hwrng_register run #6: crashed: INFO: task hung in hwrng_register run #7: crashed: INFO: task hung in hwrng_register run #8: crashed: INFO: task hung in hwrng_register run #9: crashed: INFO: task hung in hwrng_register # git bisect good 833db72142b93a89211c1e43ca0a1e2e16457756 Bisecting: 4538 revisions left to test after this (roughly 12 steps) [5cd4dc44b8a0f656100e3b6916cf73b1623299eb] Merge tag 'staging-5.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging testing commit 5cd4dc44b8a0f656100e3b6916cf73b1623299eb compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.35.2 kernel signature: ad33071164fe2890b10ec9d180bfc6a85d7d13d01bad6576025e3326051f23ae all runs: OK # git bisect bad 5cd4dc44b8a0f656100e3b6916cf73b1623299eb Bisecting: 2202 revisions left to test after this (roughly 11 steps) [ff0700f03609b9f0defacd4ce96d9519d721e0a2] Merge tag 'sound-5.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound testing commit ff0700f03609b9f0defacd4ce96d9519d721e0a2 compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.35.2 kernel signature: 9ed8298395e8b97472ff2e3e1fae5769b6baf50c081b9506b59ffa33582a00f7 all runs: crashed: INFO: task hung in hwrng_register # git bisect good ff0700f03609b9f0defacd4ce96d9519d721e0a2 Bisecting: 1184 revisions left to test after this (roughly 10 steps) [ae45d84fc36d01dcb1007f4298871eec37907904] Merge tag 'dt-5.16' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc testing commit ae45d84fc36d01dcb1007f4298871eec37907904 compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.35.2 kernel signature: 130886a3af6adc824d7d68892bffbeeb8095142ac0188a77534a2db35893dde1 all runs: OK # git bisect bad ae45d84fc36d01dcb1007f4298871eec37907904 Bisecting: 488 revisions left to test after this (roughly 9 steps) [8bd8822c83785ae669a23080d1638b0a534203b1] Merge tag 'imx-dt-5.16' of git://git.kernel.org/pub/scm/linux/kernel/git/shawnguo/linux into arm/dt testing commit 8bd8822c83785ae669a23080d1638b0a534203b1 compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.35.2 kernel signature: f958a7055f33d3967a42cbae3db2cc7a006ad182006a19ebedfa88e376c101ed run #0: crashed: INFO: task hung in hwrng_register run #1: crashed: INFO: task hung in drop_current_rng run #2: crashed: INFO: task hung in hwrng_register run #3: crashed: INFO: task hung in drop_current_rng run #4: crashed: INFO: task hung in hwrng_register run #5: crashed: INFO: task hung in hwrng_register run #6: crashed: INFO: task hung in drop_current_rng run #7: crashed: INFO: task hung in drop_current_rng run #8: crashed: INFO: task hung in hwrng_register run #9: crashed: INFO: task hung in hwrng_register # git bisect good 8bd8822c83785ae669a23080d1638b0a534203b1 Bisecting: 239 revisions left to test after this (roughly 8 steps) [2219b0ceefe835b92a8a74a73fe964aa052742a2] Merge tag 'soc-5.16' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc testing commit 2219b0ceefe835b92a8a74a73fe964aa052742a2 compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.35.2 kernel signature: 130886a3af6adc824d7d68892bffbeeb8095142ac0188a77534a2db35893dde1 all runs: OK # git bisect bad 2219b0ceefe835b92a8a74a73fe964aa052742a2 Bisecting: 123 revisions left to test after this (roughly 7 steps) [e1fd0b2acde6359a598dd4aeb158713fc0a361b2] Merge tag 'trace-v5.16-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace testing commit e1fd0b2acde6359a598dd4aeb158713fc0a361b2 compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.35.2 kernel signature: c1849a667ca8398417f2ae7bbdd05dcf1b05fd45a671f01ea12c3f1b7933d087 run #0: crashed: INFO: task hung in hwrng_register run #1: crashed: INFO: task hung in hwrng_register run #2: crashed: INFO: task hung in hwrng_register run #3: crashed: INFO: task hung in drop_current_rng run #4: crashed: INFO: task hung in hwrng_register run #5: crashed: INFO: task hung in hwrng_register run #6: crashed: INFO: task hung in hwrng_register run #7: crashed: INFO: task hung in hwrng_register run #8: crashed: INFO: task hung in hwrng_register run #9: crashed: INFO: task hung in hwrng_register # git bisect good e1fd0b2acde6359a598dd4aeb158713fc0a361b2 Bisecting: 78 revisions left to test after this (roughly 6 steps) [540061ac79f0302ae91e44e6cd216cbaa3af1757] vdpa/mlx5: Forward only packets with allowed MAC address testing commit 540061ac79f0302ae91e44e6cd216cbaa3af1757 compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.35.2 kernel signature: 3690b102baca229db1ffee729e7dc120de9e52c18872fb1c3e1fa494f6c96bf5 all runs: OK # git bisect bad 540061ac79f0302ae91e44e6cd216cbaa3af1757 Bisecting: 22 revisions left to test after this (roughly 5 steps) [f1429e6c36f5d12c9ea6edf6d704445fb048e8a6] virtio-pmem: add myself as virtio-pmem maintainer testing commit f1429e6c36f5d12c9ea6edf6d704445fb048e8a6 compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.35.2 kernel signature: efcb0d927505e4f7918e2a97abdb8f2c1927422258547ece70692588c94072df all runs: OK # git bisect bad f1429e6c36f5d12c9ea6edf6d704445fb048e8a6 Bisecting: 10 revisions left to test after this (roughly 4 steps) [e85087beedcae97e81e5d361d7d9337aa0db6f4c] eni_vdpa: add vDPA driver for Alibaba ENI testing commit e85087beedcae97e81e5d361d7d9337aa0db6f4c compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.35.2 kernel signature: 8c893f91dab5b3559f8f1f680190c8648cb4db5ee0d4d87fd8fc3342646df046 all runs: crashed: INFO: task hung in hwrng_register # git bisect good e85087beedcae97e81e5d361d7d9337aa0db6f4c Bisecting: 5 revisions left to test after this (roughly 3 steps) [2bb31abdbe55742c89f4dc0cc26fcbc8467364f6] hwrng: virtio - don't wait on cleanup testing commit 2bb31abdbe55742c89f4dc0cc26fcbc8467364f6 compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.35.2 kernel signature: fd0b720c578e8eb53696adc94e776f6b370aa936ef25cb85b82e8fb40016741c all runs: OK # git bisect bad 2bb31abdbe55742c89f4dc0cc26fcbc8467364f6 Bisecting: 2 revisions left to test after this (roughly 1 step) [218bdd20e56cab41a68481bc10c551ae3e0a24fb] vdpa/mlx5: Rename control VQ workqueue to vdpa wq testing commit 218bdd20e56cab41a68481bc10c551ae3e0a24fb compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.35.2 kernel signature: 8c893f91dab5b3559f8f1f680190c8648cb4db5ee0d4d87fd8fc3342646df046 all runs: crashed: INFO: task hung in hwrng_register # git bisect good 218bdd20e56cab41a68481bc10c551ae3e0a24fb Bisecting: 0 revisions left to test after this (roughly 1 step) [bf3175bc50a3754dc427e2f5046e17a9fafc8be7] hwrng: virtio - add an internal buffer testing commit bf3175bc50a3754dc427e2f5046e17a9fafc8be7 compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.35.2 kernel signature: 332dc699cec4c1ed6076877b452a4ca4806034d3d4ada90186fe51e033d519ea run #0: crashed: INFO: task hung in hwrng_register run #1: crashed: INFO: task hung in hwrng_register run #2: crashed: INFO: task hung in hwrng_register run #3: crashed: INFO: task hung in hwrng_register run #4: crashed: INFO: task hung in hwrng_register run #5: crashed: INFO: task hung in hwrng_register run #6: crashed: INFO: task hung in hwrng_register run #7: crashed: INFO: task hung in drop_current_rng run #8: crashed: INFO: task hung in hwrng_register run #9: crashed: INFO: task hung in hwrng_register # git bisect good bf3175bc50a3754dc427e2f5046e17a9fafc8be7 2bb31abdbe55742c89f4dc0cc26fcbc8467364f6 is the first bad commit commit 2bb31abdbe55742c89f4dc0cc26fcbc8467364f6 Author: Laurent Vivier Date: Thu Oct 28 12:11:09 2021 +0200 hwrng: virtio - don't wait on cleanup When virtio-rng device was dropped by the hwrng core we were forced to wait the buffer to come back from the device to not have remaining ongoing operation that could spoil the buffer. But now, as the buffer is internal to the virtio-rng we can release the waiting loop immediately, the buffer will be retrieve and use when the virtio-rng driver will be selected again. This avoids to hang on an rng_current write command if the virtio-rng device is blocked by a lack of entropy. This allows to select another entropy source if the current one is empty. Signed-off-by: Laurent Vivier Link: https://lore.kernel.org/r/20211028101111.128049-3-lvivier@redhat.com Signed-off-by: Michael S. Tsirkin drivers/char/hw_random/virtio-rng.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) culprit signature: fd0b720c578e8eb53696adc94e776f6b370aa936ef25cb85b82e8fb40016741c parent signature: 332dc699cec4c1ed6076877b452a4ca4806034d3d4ada90186fe51e033d519ea revisions tested: 16, total time: 4h0m11.236774647s (build: 1h43m50.692911036s, test: 2h14m21.574367476s) first good commit: 2bb31abdbe55742c89f4dc0cc26fcbc8467364f6 hwrng: virtio - don't wait on cleanup recipients (to): ["linux-crypto@vger.kernel.org" "lvivier@redhat.com" "mst@redhat.com"] recipients (cc): ["herbert@gondor.apana.org.au" "linux-kernel@vger.kernel.org" "lvivier@redhat.com" "mpm@selenic.com" "mst@redhat.com"]