bisecting cause commit starting from 728254541ebcc7fee869c3c4c3f36f96be791edb building syzkaller on 7509bf360eba1461ac6059e4cacfbc29c9d2d4c7 testing commit 728254541ebcc7fee869c3c4c3f36f96be791edb with gcc (GCC) 8.1.0 run #0: crashed: WARNING: refcount bug in kobject_get run #1: crashed: WARNING in kernfs_get run #2: crashed: WARNING in kernfs_get run #3: crashed: WARNING: refcount bug in kobject_get run #4: crashed: WARNING: refcount bug in kobject_get run #5: crashed: WARNING: refcount bug in kobject_get run #6: crashed: WARNING in kernfs_get run #7: crashed: WARNING in kernfs_get run #8: crashed: WARNING in kernfs_get run #9: crashed: WARNING in kernfs_get testing release v5.1 testing commit e93c9c99a629c61837d5a7fc2120cd2b6c70dbdd with gcc (GCC) 8.1.0 run #0: crashed: WARNING: refcount bug in kobject_get run #1: crashed: WARNING in kernfs_get run #2: crashed: WARNING: refcount bug in kobject_get run #3: crashed: general protection fault in idr_remove run #4: crashed: WARNING in kernfs_get run #5: crashed: WARNING: refcount bug in kobject_get run #6: crashed: general protection fault in kernfs_add_one run #7: crashed: WARNING: refcount bug in kobject_get run #8: crashed: WARNING in kernfs_get run #9: crashed: WARNING in kernfs_get testing release v5.0 testing commit 1c163f4c7b3f621efff9b28a47abb36f7378d783 with gcc (GCC) 8.1.0 run #0: crashed: WARNING in kernfs_get run #1: crashed: general protection fault in kernfs_add_one run #2: crashed: WARNING in kernfs_get run #3: crashed: WARNING in kernfs_get run #4: crashed: WARNING in kernfs_get run #5: crashed: WARNING in kernfs_get run #6: crashed: general protection fault in kernfs_add_one run #7: crashed: WARNING in kernfs_get run #8: crashed: WARNING in kernfs_get run #9: crashed: WARNING: refcount bug in kobject_get testing release v4.20 testing commit 8fe28cb58bcb235034b64cbbb7550a8a43fd88be with gcc (GCC) 8.1.0 run #0: crashed: general protection fault in kernfs_add_one run #1: crashed: WARNING in kernfs_get run #2: crashed: WARNING in kernfs_get run #3: crashed: general protection fault in kernfs_add_one run #4: crashed: general protection fault in kernfs_add_one run #5: crashed: WARNING in kernfs_get run #6: crashed: general protection fault in corrupted run #7: crashed: WARNING in kernfs_get run #8: crashed: WARNING: refcount bug in kobject_get run #9: crashed: WARNING in kernfs_get testing release v4.19 testing commit 84df9525b0c27f3ebc2ebb1864fa62a97fdedb7d with gcc (GCC) 8.1.0 run #0: crashed: general protection fault in kernfs_add_one run #1: crashed: WARNING in kernfs_get run #2: crashed: WARNING: refcount bug in kobject_get run #3: crashed: general protection fault in kernfs_add_one run #4: crashed: general protection fault in kernfs_add_one run #5: crashed: WARNING: refcount bug in kobject_get run #6: crashed: WARNING in kernfs_get run #7: crashed: WARNING in kernfs_get run #8: crashed: WARNING in kernfs_get run #9: crashed: WARNING in kernfs_get testing release v4.18 testing commit 94710cac0ef4ee177a63b5227664b38c95bbf703 with gcc (GCC) 8.1.0 all runs: OK # git bisect start v4.19 v4.18 Bisecting: 7596 revisions left to test after this (roughly 13 steps) [db06f826ec12bf0701ea7fc0a3c0aa00b84417c8] Merge tag 'clk-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux testing commit db06f826ec12bf0701ea7fc0a3c0aa00b84417c8 with gcc (GCC) 8.1.0 all runs: OK # git bisect good db06f826ec12bf0701ea7fc0a3c0aa00b84417c8 Bisecting: 3768 revisions left to test after this (roughly 12 steps) [cd9b44f90763c3367e8dd0601849ffb028e8ba52] Merge branch 'akpm' (patches from Andrew) testing commit cd9b44f90763c3367e8dd0601849ffb028e8ba52 with gcc (GCC) 8.1.0 run #0: crashed: WARNING in kernfs_get run #1: crashed: general protection fault in kernfs_add_one run #2: crashed: WARNING in kernfs_get run #3: crashed: WARNING: refcount bug in kobject_get run #4: crashed: WARNING: refcount bug in kobject_get run #5: crashed: WARNING in kernfs_get run #6: crashed: WARNING: refcount bug in kobject_get run #7: crashed: WARNING: refcount bug in kobject_get run #8: crashed: WARNING in kernfs_get run #9: crashed: WARNING: refcount bug in kobject_get # git bisect bad cd9b44f90763c3367e8dd0601849ffb028e8ba52 Bisecting: 2297 revisions left to test after this (roughly 11 steps) [336722eb9d9732c5a497fb6299bf38cde413592b] Merge tag 'tty-4.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty testing commit 336722eb9d9732c5a497fb6299bf38cde413592b with gcc (GCC) 8.1.0 all runs: OK # git bisect good 336722eb9d9732c5a497fb6299bf38cde413592b Bisecting: 1122 revisions left to test after this (roughly 10 steps) [d5acba26bfa097a618be425522b1ec4269d3edaf] Merge tag 'char-misc-4.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc testing commit d5acba26bfa097a618be425522b1ec4269d3edaf with gcc (GCC) 8.1.0 run #0: OK 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: boot failed: WARNING: workqueue cpumask: online intersect > possible intersect # git bisect good d5acba26bfa097a618be425522b1ec4269d3edaf Bisecting: 547 revisions left to test after this (roughly 9 steps) [bfebeb16722d93caf7870b63aa7d094b6843479a] Merge tag 'rtc-4.19' of git://git.kernel.org/pub/scm/linux/kernel/git/abelloni/linux testing commit bfebeb16722d93caf7870b63aa7d094b6843479a with gcc (GCC) 8.1.0 run #0: crashed: WARNING in kernfs_get run #1: crashed: WARNING in kernfs_get run #2: crashed: WARNING in sysfs_remove_group run #3: crashed: WARNING: refcount bug in kobject_get run #4: crashed: WARNING: refcount bug in kobject_get run #5: crashed: WARNING in kernfs_get run #6: crashed: WARNING in kernfs_get run #7: crashed: WARNING in kernfs_get run #8: crashed: WARNING in kernfs_get run #9: crashed: WARNING in sysfs_remove_group # git bisect bad bfebeb16722d93caf7870b63aa7d094b6843479a Bisecting: 300 revisions left to test after this (roughly 8 steps) [1009aa1205c2c5e9101437dcadfa195708d863bf] Merge tag 'riscv-for-linus-4.19-mw0' of git://git.kernel.org/pub/scm/linux/kernel/git/palmer/riscv-linux testing commit 1009aa1205c2c5e9101437dcadfa195708d863bf with gcc (GCC) 8.1.0 run #0: crashed: WARNING: refcount bug in kobject_get run #1: crashed: WARNING: refcount bug in kobject_get run #2: crashed: WARNING: refcount bug in kobject_get run #3: crashed: WARNING: refcount bug in kobject_put run #4: crashed: WARNING in kernfs_get run #5: crashed: WARNING in kernfs_get run #6: crashed: WARNING: refcount bug in kobject_get run #7: crashed: general protection fault in kernfs_add_one run #8: crashed: WARNING: refcount bug in kobject_get run #9: crashed: WARNING in kernfs_get # git bisect bad 1009aa1205c2c5e9101437dcadfa195708d863bf Bisecting: 130 revisions left to test after this (roughly 7 steps) [13bf2cf9e2d1e0e56088ec6342c2726704100647] Merge tag 'dmaengine-4.19-rc1' of git://git.infradead.org/users/vkoul/slave-dma testing commit 13bf2cf9e2d1e0e56088ec6342c2726704100647 with gcc (GCC) 8.1.0 run #0: crashed: WARNING: refcount bug in kobject_get run #1: crashed: WARNING in kernfs_get run #2: crashed: WARNING in kernfs_get run #3: crashed: WARNING in kernfs_get run #4: crashed: general protection fault in kernfs_add_one run #5: crashed: WARNING in kernfs_get run #6: crashed: general protection fault in kernfs_add_one run #7: crashed: general protection fault in kernfs_add_one run #8: crashed: WARNING in kernfs_get run #9: crashed: general protection fault in kernfs_add_one # git bisect bad 13bf2cf9e2d1e0e56088ec6342c2726704100647 Bisecting: 83 revisions left to test after this (roughly 6 steps) [7f38abf220e2c800a2c451372e9f07ed5fd0ea49] mmc: core: improve reasonableness of bus width setting for HS400es testing commit 7f38abf220e2c800a2c451372e9f07ed5fd0ea49 with gcc (GCC) 8.1.0 run #0: crashed: WARNING in batadv_mcast_mla_tt_retract 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 7f38abf220e2c800a2c451372e9f07ed5fd0ea49 Bisecting: 29 revisions left to test after this (roughly 5 steps) [2061594c612c4535b14bcd062a5bcf308bdd2b98] mmc: sdhci-xenon: mark expected switch fall-through testing commit 2061594c612c4535b14bcd062a5bcf308bdd2b98 with gcc (GCC) 8.1.0 all runs: OK # git bisect good 2061594c612c4535b14bcd062a5bcf308bdd2b98 Bisecting: 14 revisions left to test after this (roughly 4 steps) [57322d542ffe01076c9df10d38e3ec0a58f9d83a] mmc: sdhci: Add support for O2 eMMC HS200 mode testing commit 57322d542ffe01076c9df10d38e3ec0a58f9d83a with gcc (GCC) 8.1.0 all runs: OK # git bisect good 57322d542ffe01076c9df10d38e3ec0a58f9d83a Bisecting: 7 revisions left to test after this (roughly 3 steps) [29aba07aea0e36c996001ca3f8997316ebefe0e1] mmc: mmci: Add and implement a ->dma_setup() callback for qcom dml testing commit 29aba07aea0e36c996001ca3f8997316ebefe0e1 with gcc (GCC) 8.1.0 all runs: OK # git bisect good 29aba07aea0e36c996001ca3f8997316ebefe0e1 Bisecting: 3 revisions left to test after this (roughly 2 steps) [1389690be14601995f55417a129b89257c477997] mmc: sunxi: remove output of virtual base address testing commit 1389690be14601995f55417a129b89257c477997 with gcc (GCC) 8.1.0 all runs: OK # git bisect good 1389690be14601995f55417a129b89257c477997 Bisecting: 1 revision left to test after this (roughly 1 step) [5c99826b27d0afd4c05c2013385b17037f579cf9] mmc: renesas_sdhi: Fix sampling clock position selecting testing commit 5c99826b27d0afd4c05c2013385b17037f579cf9 with gcc (GCC) 8.1.0 all runs: OK # git bisect good 5c99826b27d0afd4c05c2013385b17037f579cf9 Bisecting: 0 revisions left to test after this (roughly 0 steps) [e401bfdadd2dc0f59bf76220236285130f072190] mmc: tmio: remove unneeded variable in tmio_mmc_start_command() testing commit e401bfdadd2dc0f59bf76220236285130f072190 with gcc (GCC) 8.1.0 all runs: OK # git bisect good e401bfdadd2dc0f59bf76220236285130f072190 7f38abf220e2c800a2c451372e9f07ed5fd0ea49 is the first bad commit commit 7f38abf220e2c800a2c451372e9f07ed5fd0ea49 Author: Hongjie Fang Date: Tue Jul 31 10:55:09 2018 +0800 mmc: core: improve reasonableness of bus width setting for HS400es mmc_select_hs400es() calls mmc_select_bus_width() which will continue to set 4bit transfer mode if fail to set 8bit mode. The bus width should not be set to 4bit in HS400es. When fail to set 8bit mode, need return error directly for HS400es. Signed-off-by: Hongjie Fang Signed-off-by: Ulf Hansson :040000 040000 9f2645259bd025d652346af3e823e36c2a08e6ea 535ba286af3537cee433b3249fbf1904bcf0bf77 M drivers revisions tested: 20, total time: 4h57m56.184787894s (build: 1h50m2.027189641s, test: 3h1m39.836724157s) first bad commit: 7f38abf220e2c800a2c451372e9f07ed5fd0ea49 mmc: core: improve reasonableness of bus width setting for HS400es cc: ["hongjiefang@asrmicro.com" "linux-kernel@vger.kernel.org" "linux-mmc@vger.kernel.org" "ulf.hansson@linaro.org"] crash: WARNING in batadv_mcast_mla_tt_retract bond0 (unregistering): Releasing backup interface bond_slave_1 bond0 (unregistering): Releasing backup interface bond_slave_0 bond0 (unregistering): Released all slaves WARNING: CPU: 1 PID: 15961 at net/batman-adv/multicast.c:337 batadv_mcast_mla_tt_retract+0x312/0x520 net/batman-adv/multicast.c:353 kobject: 'rfkill26395' (000000009b2b4d07): kobject_add_internal: parent: 'hci5', set: 'devices' Kernel panic - not syncing: panic_on_warn set ... CPU: 1 PID: 15961 Comm: kworker/u4:8 Not tainted 4.18.0-rc5+ #1 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: bat_events batadv_mcast_mla_update Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x109/0x15a lib/dump_stack.c:113 panic+0x1c6/0x36b kernel/panic.c:184 __warn.cold.8+0x120/0x168 kernel/panic.c:536 report_bug+0x1a4/0x200 lib/bug.c:186 fixup_bug arch/x86/kernel/traps.c:178 [inline] do_error_trap+0x200/0x350 arch/x86/kernel/traps.c:296 do_invalid_op+0x1b/0x20 arch/x86/kernel/traps.c:316 invalid_op+0x14/0x20 arch/x86/entry/entry_64.S:992 RIP: 0010:batadv_mcast_mla_tt_retract+0x312/0x520 net/batman-adv/multicast.c:337 Code: e8 23 29 43 fb 48 85 db 49 89 dc 0f 85 a8 fd ff ff 48 83 c4 30 5b 41 5c 41 5d 41 5e 41 5f 5d c3 49 8d 74 kobject: 'hci1' (00000000a3492d2a): kobject_add_internal: parent: 'bluetooth', set: 'devices' 24 10 e9 17 ff ff ff <0f> 0b e9 34 fd ff ff 48 89 75 b0 44 89 55 b8 44 89 45 c0 48 89 45 RSP: 0018:ffff88008ce67ac8 EFLAGS: 00010202 RAX: 0000000000000121 RBX: ffff88008ce67d30 RCX: 1ffff10010bb39c5 RDX: 1ffff100149d25ec RSI: ffff88008ce67c30 RDI: ffff8800a4e92f60 RBP: ffff88008ce67b20 R08: ffff88008ce67c70 R09: ffffed0015da472a R10: ffffed0015da472a R11: ffff8800aed23953 R12: ffff8800a4e92f60 R13: ffff88008ce67c30 R14: 0000000000000000 R15: ffff88008ce67c70 kobject: 'hci1' (00000000a3492d2a): kobject_uevent_env __batadv_mcast_mla_update net/batman-adv/multicast.c:635 [inline] batadv_mcast_mla_update+0x456/0x2110 net/batman-adv/multicast.c:661 kobject: 'rfkill26395' (000000009b2b4d07): kobject_uevent_env process_one_work+0x830/0x1650 kernel/workqueue.c:2153 worker_thread+0x85/0xb60 kernel/workqueue.c:2296 kthread+0x316/0x3d0 kernel/kthread.c:246 kobject: 'rfkill26395' (000000009b2b4d07): fill_kobj_path: path = '/devices/virtual/bluetooth/hci5/rfkill26395' ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:412 Kernel Offset: disabled Rebooting in 86400 seconds..