OK, reverted the commit, c55d7b5e6426 (“powerpc: Remove STRICT_KERNEL_RWX incompatibility with RELOCATABLE”)
or set STRICT_KERNEL_RWX=n fixed the crash below and also mentioned in this thread, https://lore.kernel.org/lkml/15ac5b0e-a221-4b8c-9039-fa96b8ef7...@lca.pw/ [ 148.110969][T13115] LTP: starting chown04_16 [ 148.255048][T13380] kernel tried to execute exec-protected page (c0000000016804ac) - exploit attempt? (uid: 0) [ 148.255099][T13380] BUG: Unable to handle kernel instruction fetch [ 148.255122][T13380] Faulting instruction address: 0xc0000000016804ac [ 148.255136][T13380] Oops: Kernel access of bad area, sig: 11 [#1] [ 148.255157][T13380] LE PAGE_SIZE=64K MMU=Radix SMP NR_CPUS=256 DEBUG_PAGEALLOC NUMA PowerNV [ 148.255171][T13380] Modules linked in: loop kvm_hv kvm xfs sd_mod bnx2x mdio ahci tg3 libahci libphy libata firmware_class dm_mirror dm_region_hash dm_log dm_mod [ 148.255213][T13380] CPU: 45 PID: 13380 Comm: chown04_16 Tainted: G W 5.6.0+ #7 [ 148.255236][T13380] NIP: c0000000016804ac LR: c00800000fa60408 CTR: c0000000016804ac [ 148.255250][T13380] REGS: c0000010a6fafa00 TRAP: 0400 Tainted: G W (5.6.0+) [ 148.255281][T13380] MSR: 9000000010009033 <SF,HV,EE,ME,IR,DR,RI,LE> CR: 84000248 XER: 20040000 [ 148.255310][T13380] CFAR: c00800000fa66534 IRQMASK: 0 [ 148.255310][T13380] GPR00: c000000000973268 c0000010a6fafc90 c000000001648200 0000000000000000 [ 148.255310][T13380] GPR04: c000000d8a22dc00 c0000010a6fafd30 00000000b5e98331 ffffffff00012c9f [ 148.255310][T13380] GPR08: c000000d8a22dc00 0000000000000000 0000000000000000 c00000000163c520 [ 148.255310][T13380] GPR12: c0000000016804ac c000001ffffdad80 0000000000000000 0000000000000000 [ 148.255310][T13380] GPR16: 0000000000000000 0000000000000000 0000000000000000 0000000000000000 [ 148.255310][T13380] GPR20: 0000000000000000 0000000000000000 0000000000000000 0000000000000000 [ 148.255310][T13380] GPR24: 00007fff8f5e2e48 0000000000000000 c00800000fa6a488 c0000010a6fafd30 [ 148.255310][T13380] GPR28: 0000000000000000 000000007fffffff c00800000fa60400 c000000efd0c6780 [ 148.255494][T13380] NIP [c0000000016804ac] sysctl_net_busy_read+0x0/0x4 [ 148.255516][T13380] LR [c00800000fa60408] find_free_cb+0x8/0x30 [loop] [ 148.255528][T13380] Call Trace: [ 148.255538][T13380] [c0000010a6fafc90] [c0000000009732c0] idr_for_each+0xf0/0x170 (unreliable) [ 148.255572][T13380] [c0000010a6fafd10] [c00800000fa626c4] loop_lookup.part.1+0x4c/0xb0 [loop] [ 148.255597][T13380] [c0000010a6fafd50] [c00800000fa634d8] loop_control_ioctl+0x120/0x1d0 [loop] [ 148.255623][T13380] [c0000010a6fafdb0] [c0000000004ddc08] ksys_ioctl+0xd8/0x130 [ 148.255636][T13380] [c0000010a6fafe00] [c0000000004ddc88] sys_ioctl+0x28/0x40 [ 148.255669][T13380] [c0000010a6fafe20] [c00000000000b378] system_call+0x5c/0x68 [ 148.255699][T13380] Instruction dump: [ 148.255718][T13380] XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX [ 148.255744][T13380] XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX [ 148.255772][T13380] ---[ end trace a5894a74208c22ec ]--- [ 148.576663][T13380] [ 149.576765][T13380] Kernel panic - not syncing: Fatal exception
