Kunit ext4_mballoc_test tests found following kernel oops on Linux next. All ways reproducible on all the architectures and steps to reproduce shared in the bottom of this email. Reported-by: Linux Kernel Functional Testing <lkft@xxxxxxxxxx> Test log: --------- <6>[ 14.297909] KTAP version 1 <6>[ 14.298306] # Subtest: ext4_mballoc_test <6>[ 14.299114] # module: ext4 <6>[ 14.300048] 1..6 <6>[ 14.301204] KTAP version 1 <6>[ 14.301853] # Subtest: test_new_blocks_simple <1>[ 14.308203] Unable to handle kernel paging request at virtual address dfff800000000000 <1>[ 14.309700] KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007] <1>[ 14.310671] Mem abort info: <1>[ 14.311141] ESR = 0x0000000096000004 <1>[ 14.312969] EC = 0x25: DABT (current EL), IL = 32 bits <1>[ 14.313566] SET = 0, FnV = 0 <1>[ 14.314228] EA = 0, S1PTW = 0 <1>[ 14.314750] FSC = 0x04: level 0 translation fault <1>[ 14.316382] Data abort info: <1>[ 14.316838] ISV = 0, ISS = 0x00000004, ISS2 = 0x00000000 <1>[ 14.317742] CM = 0, WnR = 0, TnD = 0, TagAccess = 0 <1>[ 14.318637] GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0 <1>[ 14.319975] [dfff800000000000] address between user and kernel address ranges <0>[ 14.322307] Internal error: Oops: 0000000096000004 [#1] PREEMPT SMP <4>[ 14.324184] Modules linked in: <4>[ 14.326693] CPU: 1 PID: 104 Comm: kunit_try_catch Tainted: G N 6.8.0-rc6-next-20240228 #1 <4>[ 14.327913] Hardware name: linux,dummy-virt (DT) <4>[ 14.329173] pstate: 11400009 (nzcV daif +PAN -UAO -TCO +DIT -SSBS BTYPE=--) <4>[ 14.330117] pc : map_id_range_down (kernel/user_namespace.c:318) <4>[ 14.331618] lr : make_kuid (kernel/user_namespace.c:415) <trim> <4>[ 14.344145] Call trace: <4>[ 14.344565] map_id_range_down (kernel/user_namespace.c:318) <4>[ 14.345378] make_kuid (kernel/user_namespace.c:415) <4>[ 14.345998] inode_init_always (include/linux/fs.h:1375 fs/inode.c:174) <4>[ 14.346696] alloc_inode (fs/inode.c:268) <4>[ 14.347353] new_inode_pseudo (fs/inode.c:1007) <4>[ 14.348016] new_inode (fs/inode.c:1033) <4>[ 14.348644] ext4_mb_init (fs/ext4/mballoc.c:3404 fs/ext4/mballoc.c:3719) <4>[ 14.349312] mbt_kunit_init (fs/ext4/mballoc-test.c:57 fs/ext4/mballoc-test.c:314) <4>[ 14.349983] kunit_try_run_case (lib/kunit/test.c:388 lib/kunit/test.c:443) <4>[ 14.350696] kunit_generic_run_threadfn_adapter (lib/kunit/try-catch.c:30) <4>[ 14.351530] kthread (kernel/kthread.c:388) <4>[ 14.352168] ret_from_fork (arch/arm64/kernel/entry.S:861) <0>[ 14.353385] Code: 52808004 b8236ae7 72be5e44 b90004c4 (38e368a1) All code ======== 0: 52808004 mov w4, #0x400 // #1024 4: b8236ae7 str w7, [x23, x3] 8: 72be5e44 movk w4, #0xf2f2, lsl #16 c: b90004c4 str w4, [x6, #4] 10:* 38e368a1 ldrsb w1, [x5, x3] <-- trapping instruction Code starting with the faulting instruction =========================================== 0: 38e368a1 ldrsb w1, [x5, x3] <4>[ 14.354545] ---[ end trace 0000000000000000 ]--- Links: - https://qa-reports.linaro.org/lkft/linux-next-master/build/next-20240228/testrun/22877850/suite/log-parser-test/test/check-kernel-bug/log - https://qa-reports.linaro.org/lkft/linux-next-master/build/next-20240228/testrun/22877850/suite/log-parser-test/tests/ - https://qa-reports.linaro.org/lkft/linux-next-master/build/next-20240228/testrun/22877850/suite/log-parser-test/test/check-kernel-bug-43e0665fdb2d5768ac093e1634e6d9a7c65ff1b6a66af7d0c12b3bce5ca7e717/details/ Steps to reproduce: - https://tuxapi.tuxsuite.com/v1/groups/linaro/projects/lkft/tests/2czN4PCDk4BIKg76qUnQE4WkNny/reproducer -- Linaro LKFT https://lkft.linaro.org