bisecting fixing commit since f8e6dfc64f6135d1b6c5215c14cd30b9b60a0008 building syzkaller on 3fd2ea69e05557e7e0fef9b68263b4150670671c testing commit f8e6dfc64f6135d1b6c5215c14cd30b9b60a0008 compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.35.2 kernel signature: 707d2ecb85da766c7b1002fa1a5c3c2a92e28975c398659cdd8897dbf599fa60 run #0: crashed: INFO: task hung in drop_current_rng 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 drop_current_rng 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 drop_current_rng run #10: crashed: INFO: task hung in hwrng_register run #11: crashed: INFO: task hung in drop_current_rng run #12: crashed: INFO: task hung in hwrng_register run #13: crashed: INFO: task hung in drop_current_rng run #14: crashed: INFO: task hung in hwrng_register run #15: crashed: INFO: task hung in hwrng_register 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 hwrng_register testing current HEAD 5833291ab6de9c3e2374336b51c814e515e8f3a5 testing commit 5833291ab6de9c3e2374336b51c814e515e8f3a5 compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.35.2 kernel signature: 0d0fb3569131ab5d2300e951ca67512f804ce9e8989237dd545829b6803440bf all runs: OK # git bisect start 5833291ab6de9c3e2374336b51c814e515e8f3a5 f8e6dfc64f6135d1b6c5215c14cd30b9b60a0008 Bisecting: 13221 revisions left to test after this (roughly 14 steps) [cfbe9b002109621bf9a282a4a24f9415ef14b57b] Merge branch 'ipv6-ioam-encap' testing commit cfbe9b002109621bf9a282a4a24f9415ef14b57b compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.35.2 kernel signature: c354481f50c8b267643f2a7540b64b63978831b2f77a71b9360db3d232ed85f5 all runs: crashed: INFO: task hung in hwrng_register # git bisect good cfbe9b002109621bf9a282a4a24f9415ef14b57b Bisecting: 6031 revisions left to test after this (roughly 13 steps) [56d33754481fe0dc7436dc4ee4fbd44b3039361d] Merge tag 'drm-next-2021-11-03' of git://anongit.freedesktop.org/drm/drm testing commit 56d33754481fe0dc7436dc4ee4fbd44b3039361d compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.35.2 kernel signature: 0db2e18f4c2c28910ffd684ab8905a62da62e6c350f44d57f91d7b9fd6dae4eb run #0: crashed: INFO: task hung in drop_current_rng 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 56d33754481fe0dc7436dc4ee4fbd44b3039361d Bisecting: 2984 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: 896b99033f7c042a70fbe06068f98b9ca6dcb7151732ae285130c5a197e2f39a all runs: OK # git bisect bad 5cd4dc44b8a0f656100e3b6916cf73b1623299eb Bisecting: 1184 revisions left to test after this (roughly 11 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: e74ae251894283668c9e6bf89532ea30580c25912612c6beb2b7c7d391b99f80 all runs: OK # git bisect bad ae45d84fc36d01dcb1007f4298871eec37907904 Bisecting: 907 revisions left to test after this (roughly 10 steps) [25edbc383b72c2364c7b339245c1c5db84e615e1] Merge tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma testing commit 25edbc383b72c2364c7b339245c1c5db84e615e1 compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.35.2 kernel signature: 4b645fadf28961b541dac5eed5fc1e88e562eba964d3e3d16569d2eea255e7a3 all runs: crashed: INFO: task hung in hwrng_register # git bisect good 25edbc383b72c2364c7b339245c1c5db84e615e1 Bisecting: 452 revisions left to test after this (roughly 9 steps) [f97ee3e963b39e939b4869f40d2d5ecd9b8e6eb4] Merge tag 'renesas-arm-dt-for-v5.16-tag2' of git://git.kernel.org/pub/scm/linux/kernel/git/geert/renesas-devel into arm/dt testing commit f97ee3e963b39e939b4869f40d2d5ecd9b8e6eb4 compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.35.2 kernel signature: 6cf40ebc7b204029ce2afd1a1fdb39db447c87e33724bc32d1fd2bb30dc89df5 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 f97ee3e963b39e939b4869f40d2d5ecd9b8e6eb4 Bisecting: 223 revisions left to test after this (roughly 8 steps) [9271fccb001d80f26d690dd1752d6f11eb61b2e2] Merge tag 'qcom-dts-for-5.16-2' of git://git.kernel.org/pub/scm/linux/kernel/git/qcom/linux into arm/dt testing commit 9271fccb001d80f26d690dd1752d6f11eb61b2e2 compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.35.2 kernel signature: 6cf40ebc7b204029ce2afd1a1fdb39db447c87e33724bc32d1fd2bb30dc89df5 run #0: crashed: INFO: task hung in drop_current_rng 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 hwrng_register run #9: crashed: INFO: task hung in hwrng_register # git bisect good 9271fccb001d80f26d690dd1752d6f11eb61b2e2 Bisecting: 120 revisions left to test after this (roughly 7 steps) [43e1b12927276cde8052122a24ff796649f09d60] Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost testing commit 43e1b12927276cde8052122a24ff796649f09d60 compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.35.2 kernel signature: e74ae251894283668c9e6bf89532ea30580c25912612c6beb2b7c7d391b99f80 all runs: OK # git bisect bad 43e1b12927276cde8052122a24ff796649f09d60 Bisecting: 45 revisions left to test after this (roughly 6 steps) [d4ec3d5535c784c3adbc41c2bbc5d17a00a4a898] Merge tag 'vfio-v5.16-rc1' of git://github.com/awilliam/linux-vfio testing commit d4ec3d5535c784c3adbc41c2bbc5d17a00a4a898 compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.35.2 kernel signature: 56df81369f130a2dabd45876270abf411d26e30b1e930d8ff5b83007b05df7c7 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 drop_current_rng # git bisect good d4ec3d5535c784c3adbc41c2bbc5d17a00a4a898 Bisecting: 22 revisions left to test after this (roughly 5 steps) [6ae6ff6f6e7d2f304a12a53af8298e4f16ad633e] virtio-blk: validate num_queues during probe testing commit 6ae6ff6f6e7d2f304a12a53af8298e4f16ad633e compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.35.2 kernel signature: c3e88584bad727bc4c64eaaf3c8e3692e2757f8067b723c8585421053524a7b4 all runs: OK # git bisect bad 6ae6ff6f6e7d2f304a12a53af8298e4f16ad633e Bisecting: 11 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: bcb2d3211a78afa16df12eac6c9b537b74c1aefcc96ba4410c958688d2442d78 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 drop_current_rng 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 drop_current_rng # git bisect good e85087beedcae97e81e5d361d7d9337aa0db6f4c Bisecting: 5 revisions left to test after this (roughly 3 steps) [5c8e933050044d6dd2a000f9a5756ae73cbe7c44] hwrng: virtio - don't waste entropy testing commit 5c8e933050044d6dd2a000f9a5756ae73cbe7c44 compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.35.2 kernel signature: 3a38da1201b8787929babe24d3ab9e9fac917b208fd0c3bd8ad51598dad0b688 all runs: OK # git bisect bad 5c8e933050044d6dd2a000f9a5756ae73cbe7c44 Bisecting: 2 revisions left to test after this (roughly 2 steps) [edf747affc41a18ccc3a616813d4c2b6d38b46ce] vdpa/mlx5: Propagate link status from device to vdpa driver testing commit edf747affc41a18ccc3a616813d4c2b6d38b46ce compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.35.2 kernel signature: bcb2d3211a78afa16df12eac6c9b537b74c1aefcc96ba4410c958688d2442d78 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 drop_current_rng 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 drop_current_rng run #9: crashed: INFO: task hung in hwrng_register # git bisect good edf747affc41a18ccc3a616813d4c2b6d38b46ce Bisecting: 0 revisions left to test after this (roughly 1 step) [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: 9367439065c587b1172df37f6d6bd4bb527cafb3548d5674d16dca52e4395cd8 all runs: OK # git bisect bad 2bb31abdbe55742c89f4dc0cc26fcbc8467364f6 Bisecting: 0 revisions left to test after this (roughly 0 steps) [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: 0129e5fdbbcdac12fca7bcae3158ecee7746d7117d38e1b7f2886e3b4964ffc3 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 drop_current_rng run #3: crashed: INFO: task hung in hwrng_register run #4: crashed: INFO: task hung in drop_current_rng 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 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: 9367439065c587b1172df37f6d6bd4bb527cafb3548d5674d16dca52e4395cd8 parent signature: 0129e5fdbbcdac12fca7bcae3158ecee7746d7117d38e1b7f2886e3b4964ffc3 revisions tested: 17, total time: 3h53m9.43879238s (build: 1h47m12.70530959s, test: 2h3m59.814858609s) 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"]